Ornithine aminotransferase (OAT) catalyzes transfer of the delta-amino group from L-ornithine to oxo-glutarate.In plants, this reaction biochemically connects urea cycle, proline cycle, and polyamine biosynthesis pathway.OAT activity is shown to be associated with biotic and abiotic stress responses and nitrogen metabolism, but itsphysiological role is still unclear. In our study, we decided to investigate transcriptional regulation of the OAT gene inArabidopsis thaliana under normal conditions and in response to various growth regulators. In the present work, thereporter gene construct containing the Escherichia coli β-glucuronidase gene (gus) under control of the A. thaliana OATgene promoter was introduced into the genome of A. thaliana ecotype Columbia plants using the floral dip method;GUS activity was assayed in different experimental conditions including hormone treatment, low and high nitrogen andsalinity. The GUS activity was analyzed histochemically. Plants were incubated with staining solution containing X-Gluc.We show that under standard growth conditions, the promoter is active during germination and in developing floralorgans. OAT promoter activity specifically activates in response to different forms of auxin , cytokinin(6- BAP), ethylene precursor (ACC), high nitrogen and salinity. Analysis of the OAT expression by qRT-PCR confirmed thepattern observed using the GUS reporter system. The OAT gene showed a significantly elevated expression in fourday-old seedlings and in plant roots in response to auxins and cytokinins. The analysis of the OAT promoter structurereveals cis-acting regulatory DNA elements associated with auxin regulation and abiotic stresses. The results of thestudy indicate that the OAT gene is involved in developmental processes and is regulated by auxin and cytokinins. The ornithine-δ-aminotransferase (OAT) is a mitochondrialpyridoxal-5-phosphate (PLP)-dependent enzyme that transfersan amino group from ornithine to oxo-glutarate with formationof glutamate-1-semialdehyde (GSA) and glutamate . Although the biochemical function ofOAT is known, its biological role in plants is not fully understood.On the one hand, OAT is involved in metabolism of ornithine,which takes part in numerous biochemical processes inplants, such as arginine metabolism, synthesis of polyaminesand alkaloids . Onthe other hand, one of the products of the reaction mediated byOAT, namely GSA, is involved in proline production. It readilyinterconverts into the cyclic 1-pyrroline-5-carboxylate (P5C),an intermediate in the proline biosynthesis, in a non-enzymaticfashion . Proline is involved in plantstress response  anddevelopment . It has already beenshown in various experiments on several plant species thatoverexpression of the OAT gene is associated with increasedproline content and resistance to abiotic stresses . It is tempting to assume thatOAT might link biological processes related to proline, ornithineand P5C metabolism, such as nitrogen recycling, stressresponse, secondary metabolism, growth and development.We have previously shown that OAT overexpression in tobaccoincreases salt stress resistance. Interestingly, the levelof proline accumulation in OAT overexpressing lines did notdiffer from that of WT plants under both normal and stressconditions, suggesting that OAT might contribute to stressresistance through processes not related to proline synthesis. On a model of transgenic tobaccoplants expressing GUS under the control of putative Arabidopsisthaliana OAT promoter we showed that the promoter activityis associated with meristems and zones of active growth. This observation suggests that theOAT gene might be involved in developmental processes. Thepresent study aims to investigate transcriptional regulation ofthe OAT gene in A. thaliana under normal conditions and inresponse to various growth regulators.Development of transgenic Arabidopsis harboring AtOATpromoter construct. The 1844 bp region upstream of theOAT gene translation start  was clonedin the promoterless vector pBI101 with the formation of theP1844 construct . The resultingvector contains the expression cassette harboring the β-glucuronidase(gus) reporter gene under the control of putativeA. thaliana OAT promoter. A. thaliana plants ecotype Columbiawere grown at 22 °C in a long-day growth conditions (16 hof light and 8 h of dark). Construct P1844 was transformedinto Agrobacterium tumefaciens strain AGL0, which was usedto transform A. thaliana by floral dip method . T1 transformants were screened on 1/2 MS agar platescontaining 50 mg/L kanamycin, transferred to pots and grownto maturity until the T2 generation seeds were harvested.T2 seeds were germinated on 1/2 MS agar plates containing50 mg/L kanamycin and resistant plants were tested for thepresence of GUS activity by histochemical assay. Six independenttransgenic T2 lines showing the presence of GUS activityin seedlings were selected for further experiments. Plants fromthe selected lines were grown to maturity and T3 generationseeds were harvested. Thus, six independent T3 transgeniclines have been obtained.GUS staining. The histochemical staining method  was used to visualize GUS (Escherichia coliβ-glucuronidase) activity in seedlings grown on agar platesand plant parts grown in soil (5-week-old plants). Wholeseedlings and different plant parts were incubated in X-Glucsolution Triton-X) for 24 h at 37 °C. Chlorophyll was removed byrepeated washing in 70 % (v/v) ethanol. GUS activity wasobserved using a ZEISS Stemi 2000-C microscope coupledwith an AxioCam HRc cameraExperimental treatments. Surface-sterilized seeds of sixindependent transgenic A. thaliana lines (T3) were germinatedon MS plates supplemented with 1 % sucrose, 0.7 % agar. Todetect promoter activity during germination, histochemicalassay was performed for seedlings at 3rd, 5th, 6th and 14th dayafter sowing (DAS) on plates. For experimental treatments,one-week-old seedlings were transferred to the same mediumsupplemented with the following growth regulators (fromSigma-Aldrich): auxins , cytokinins , gibberellic acid (10 μМ GA3),100 μМ abscisic acid, 1 mМ methyl jasmonate, ethyleneprecursor (50 μМ ACC), high nitrogen (10 mM NH4NO3),high salinity (200 mM NaCl). For low nitrogen treatment,MS NH4NO3-free medium (Duchefa Biochemie) was used.GUS activity was assayed after 1, 4, 6 and 8 days of treatment.For cold and heat treatment, two-week-old transgenicplants were used. For cold treatment, plates with seedlingswere incubated at +4 °C for 4 h, then for 2 h at 22 °C; forheat treatment, plates were incubated at +50 °C for 15 min,then 6 h at 22 °C.Gene expression analysis (RNA isolation and qRT‑PCR).Wild type Col-0 seed was surface sterilized with 12.5 %bleach  and 70 % ethanol and germinated on 1/2 MSmedium . To measure expression ofthe OAT gene during germination and early development,total RNA was isolated from whole seedlings at 4th, 7th and14th DAS. For experimental treatments, one-week seedlingswere transferred to 1/2 MS medium supplemented with differentgrowth regulators , and control, to 1/2 MSmedium. For each treatment, experiment was performed inthree biological replicates. There were 30 seedlings per eachbiological replicate. Total RNA was isolated from roots ofseedlings after 6 days of treatment with the RNeasy PlantMini Kit (Qiagen). RNA was treated with DNAse (QIAGENRNase-Free DNase Set). The concentration of RNA wasmeasured by NanoDrop 2000 (Thermo Scientific). The qualityof RNA was evaluated using Bioanalyzer 2100 (Agilent).First strand cDNA was synthesized from 1 μg of total RNAusing BIORAD iScript™ Reverse Transcription Supermixfor RT-qPCR. For qRT-PCR analysis, cDNA was diluted tentimes. PCR was performed in a final volume of 15 μL: 3 μLof 5х Low Rox buffer (SibEnzyme), 0.15 μL of each primer(10 μM) and the taqman probe solution, 3 μL of diluted cDNA. The primers and probes were designed using IDT’sPrimerQuest Tool (https://eu.idtdna.com/PrimerQuest/). Thecomparative threshold cycle method was used to determinerelative gene expression, with the expression of EF1-alfa andF-box (accession no. At1g13320 and At5g15710) serving asan internal control. The structures of primers and probes aregiven in Suppl. Table 11. The relative expression levels ofOAT mRNA in all the treated samples were quantified usingan Applied biosystems 7500 Real Time PCR System. Eachreaction was performed in three technical replicates usingthe following program of the qRT-PCR; 95 °C for 10 min;45 cycles of 95 °C for 15 s, 68 °C for 60 s. Statistical analysiswas performed using Student’s t-test. p-values < 0.05 wereconsidered significant.http://www.bionet.nsc.ru/vogis/download/pict-2022-26/appx4.pdfSupplementary Tables 1–4 are available in the online version of the paper:Web tools used for cis-acting regulatory DNA elementssearch and expression data analysis. Search of cis-actingregulatory elements was performed using the PLACE database. Gene expression data from different microarray and RNA-seq experiments were extracted fromExpression Atlas and Arabidopsis eFP Browser Web tools.Tissue-specific promoter activation at different developmentalstages and under experimental treatments. StrongGUS staining was detected in hypocotyls and cotyledons ofseedlings at 3–4th DAS. At later stages, the GUS activity wasobserved only in cotyledons. In 6- and 14- DAS seedlings, theGUS activity was found only in the distal parts of cotyledons. During flower development, the GUS activity wasobserved in anthers, carpels and developing seeds of growingsiliques .To get a deeper insight into the transcriptional regulationof OAT, transgenic seedlings were subjected to experimentaltreatments including different concentrations of growth regulatorsand phytohormones auxins, cytokinins, gibberellin, ABA,methyl jasmonate, ethylene precursor (ACC), low and highnitrogen, high salinity, cold and heat stress . We observed tissue-specific OAT promoter activity inresponse to different forms of auxin ,cytokinin (6-BAP), and ACC. The strongest GUS activity wasobserved in response to 2,4-D in whole plant. Treatment withIAA and NAA caused GUS activation in root tips; treatmentwith 6-BAP – in the zone of root hairs. Treatment with ACC,salinity and nitrogen activated promoter along the whole root.OAT gene expression analysis. The qRT-PCR resultsshowed that transcript levels of the OAT gene are significantlyhigher in four-day-old seedlings, than at later developmentalstages . In experimental treatments, the OATgene showed significantly ( p ≤ 0.05) elevated expression inresponse to different forms of auxin  andcytokinin (6-BAP) in comparison to control conditions. Treatmentwith synthetic auxin 2,4-D led to 3-fold increase in OATexpression level in roots .Cis-acting regulatory DNA elements search and transcriptomicdata analysis. Сis-acting regulatory DNA elementssearch revealed putative transcription factors bindingsites, corresponding to different physiological processes, includinghyperosmotic and hypoosmotic stress response, auxinresponse, axillary bud dormancy control, specific regulation inontogenesis (Suppl. Table 3). Meta-analysis of microarray andRNA-seq data  shows that the OAT expression level changes in responseto cold, drought, heat, wounding, osmotic and salt stress. Expressionincreases in response to pathogens Botrytis cinerea,Pseudomonas syringae, Phytophthora infestans and someother infections. Altered OAT gene expression was observedin response to different hormones: it increased in response to3 h of treatment with ABA, methyl jasmonate, and decreasedin response to 3 h of treatment with brassinosteroids. The OATgene demonstrates high expression in seeds, siliques, embryos,senescent leaves, floral organs in A. thaliana (Suppl. Table 4).For more than a decade OAT has been considered an enzymeinvolved in metabolic response to different stress conditions,such as osmotic stress, pathogen attack and ROS production,nitrogen starvation, etc. . This enzyme belongs to the networkof nitrogen-metabolizing pathways in plants, affected byvarious environmental stimuli. It has been shown that plantsaccumulate proline during stress conditions . The results of Funck et al. (2008) and ourprevious study did not support the hypothesis of OAT contributionto proline accumulation. Instead, a specific role of the OATgene in plant developmental and growth processes under bothnormal and stress conditions is hypothesized . This study provides a deeper insight intothe role of the OAT gene in plant development.The important metabolic role of the OAT was clearly shownin an experiment where OAT-deficient plants failed to developwith arginine or ornitine as the sole nitrogen source . This result demonstrated that OAT is requiredfor utilization of arginine and ornithine. The present studydemonstrates high OAT promoter activity and elevated OATtranscript level during seed germination. These results are inagreement with available transcriptomic data . In arginine catabolism, OAT acts downstream ofarginase . Arginine is regarded as a majornitrogen storage compound in seeds. Urease and arginaseactivities increase sharply during germination in A. thaliana and other plant species . Taken together, these data provide evidence for OATinvolvement in nitrogen reorganization during seed germinationtogether with other enzymes of arginine catabolism.Our work also shows that the OAT gene promoter is activeduring inflorescence development. This observation isin accordance with recent findings showing that the OATenzymeplays a role in flower development and seed settingin rice . It has been reported that rice plantswith a mutated OAT gene (OsOAT mutants) have differentabnormalities in inflorescence and seed development. Themutant phenotype of the OsOAT mutant could be rescued byapplication of urea . Authors assumed thatOAT mediates arginase activity and plays a role in regulationof nitrogen reutilization, which is critical for developing tissues.Taking into account the association between the OAT geneexpression and proline accumulation , it can be assumed that OAT enzyme activity may also play a role in control of proline level duringinflorescence development. It has been reported that someproline metabolic enzymes can regulate a number of developmentalprocesses including flowering time , pollen development  and root growth . Prolineis known to be accumulated in reproductive organs of manyplant species . Ornithine to prolineconversion is mediated by the plant oncogene RolD , the overexpression of which stimulates floweringand affects inflorescence architecture in transgenic tobaccoplants . This study shows that the OATpromoter is active in inflorescences on different developmentalstages , suggesting that the OAT enzyme canconvert ornithine to proline directly or indirectly via argininecatabolism and glutamate production and might serve as aregulator of proline level during inflorescence development.Tissue-specific activation of the OAT transcription in rootsin response to auxin and cytokinin treatments, as well as thepresence of the auxin-responsive element in the OAT promoter(see Suppl. Table 3) allow us to assume specific regulation ofthe OAT gene during root growth and development. Recentfindings show the importance of nutrient and especially nitrogensignaling for root development and its interplay with hormoneregulation. Thus, cytokinins negatively regulate uptakeof nitrogen, but enhance nitrate distribution and translocation. Auxin level was shown to be elevated in rootsof plants growing on a low-nitrogen medium, while in roots ofplants growing on a medium with high nitrate concentrationthe auxin level was decreased. The reduction of auxin contentcorrelated with the degree of inhibition of root growth andlateral root development . The root growthregulation is associated with local reorganization of nitrogenmetabolism . Thereby, OAT may play animportant role in hormone-dependent fine-tuning of nitrogenmetabolism during the process of root development.The data regarding the OAT transcription activation in a widespectrum of experimental conditions, which was shown inour experiment and other studies, support the hypothesis thatornithine aminotransferase provides a link between differentbiochemical pathways of nitrogen conversion and contributesto the complicated signaling network regulating plantdevelopment.The authors declare no conflict of interest.Ballas N., Wong L.M., Theologis A. 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Estrogen receptor beta signaling in CD8+ T cells boosts T cell receptor activation and antitumor immunity through a phosphotyrosine switch. J Immunother Cancer 2021;9:e001932. doi:10.1136/jitc-2020-001932Yuan B, Clark CA, Wu B, This article has been corrected since it first published. The provenance and peer review statement has been added.


DTG/3TC is a complete 2-drug regimen (2DR) for the treatment of HIV-1 infection. Non-inferior virologic efficacy has been proven over 3 years in treatment-naive people living with HIV (PLWH) and 2 years in a stable switch setting. TANGO, a randomized, open-label, non-inferiority study, evaluates efficacy and safety of switching to DTG/3TC in PLWH who are virologically suppressed  vs remaining on a 3- or 4-drug TAF-based regimen (TBR), stratified by baseline 3rd agent class. Week 144 analyses assessed non-inferiority (NI) with a 4% NI margin for Snapshot virologic failure (VF) and 8% for virologic success .P=0.044 (2-sided). Snapshot VS was high in both arms and demonstrated non-inferiority (Table). Zero pts on DTG/3TC and 3 (0.8%) on TBR met confirmed virologic withdrawal criteria with no resistance observed. Zero pts on DTG/3TC and 6 (1.6%) on TBR discontinued for lack of efficacy. Overall AE rates were similar between arms (Table). TC, LDL-C, and triglycerides improved with DTG/3TC, HDL-C improved with TBR, with no difference in TC/HDL-C ratio between arms. Changes in eGFR (cystatin C) and proximal tubular function marker were similar across arms. Adjusted mean change from BL in weight was 2.2 and 1.7 kg in the DTG/3TC and TBR arms, respectively, and proportion of pts with > 10% weight increase was similar across arms .Of 741 randomized/exposed pts , most pts entered the study on EVG/c (66%). For Week 144 Snapshot VF, switching to DTG/3TC was non-inferior to continuing TBR in the ITT-E analysis: 0.3% vs 1.3%; adjusted difference (95% CI): −1.1%  and superior to TBR in the per-protocol analysis: 0% vs 1.1%; adjusted difference: −1.1% ; Table. Efficacy and Key Safety Results for the ITT-E and Safety PopulationSwitching to the 2-drug regimen of DTG/3TC from a TAF-based 3- or 4-drug regimen resulted in high, non-inferior efficacy with zero confirmed virologic withdrawals and good tolerability over 3 years of treatment. DTG/3TC 2DR is a robust switch option with durable efficacy, good safety and tolerability, and a high barrier to resistance.Olayemi Osiyemi, M.D, Gilead Merck (Advisor or Review Panel member)ViiV Healthcare  Fiona Bisshop, MBBBS, Gilead (Grant/Research Support)ViiV Healthcare (Grant/Research Support) Stéphane De Wit, MD, Gilead (Grant/Research Support)Janssen (Grant/Research Support)Merck Sharpe & Dohme (Grant/Research Support)ViiV Healthcare (Grant/Research Support) Joaquín Portilla, MD, AbbVie Gilead Janssen Merck Sharpe & Dohme ViiV Healthcare  Jean-Pierre Routy, MD, FRCPC, ViiV Healthcare (Grant/Research Support) Mounir Ait-Khaled, PhD, ViiV Healthcare (Employee) Keith Pappa, PharmD, Glaxo Smith Kline (Shareholder)ViiV Healthcare (Employee) Ruolan Wang, Master of Science, ViiV Healthcare (Employee) Peter Leone, MD, viiv healthcare (Employee) Jonathan Wright, MSc, GlaxoSmithKline  Brian Wynne, MD, ViiV Healthcare  Jean A. van Wyk, MB,ChB, GlaxoSmithKline (Shareholder)ViiV Healthcare (Employee) Michael Aboud, MBChB, MRCP, GlaxoSmithKline (Shareholder)ViiV Healthcare (Employee) Kimberly Smith, MD, GlaxoSmithKline (Shareholder)ViiV Healthcare (Employee)


The gut microbiota is associated with diverse age-related disorders. Several rejuvenation methods, such as probiotic administration and faecal microbiota transplantation, have been applied to alter the gut microbiome and promote healthy ageing. Nevertheless, prolongation of the health span of aged mice by remodelling the gut microbiome remains challenging.Akkermansia and the butyrate biosynthesis pathway in the rejuvenated mouse group. Furthermore, oral administration of Akkermansia sufficiently ameliorated the senescence-related phenotype in the intestinal systems in aged mice and extended the health span, as evidenced by the frailty index and restoration of muscle atrophy.Here, we report the changes in gut microbial communities and their functions in mouse models during ageing and three rejuvenation procedures including co-housing, serum-injection and parabiosis. Our results showed that the compositional structure and gene abundance of the intestinal microbiota changed dynamically during the ageing process. Through the three rejuvenation procedures, we observed that the microbial community and intestinal immunity of aged mice were comparable to those of young mice. The results of metagenomic data analysis underscore the importance of the high abundance of Akkermansia. Our results provide a rationale for developing therapeutic strategies to achieve healthy active ageing.In conclusion, the changes in key microbial communities and their functions during ageing and three rejuvenation procedures, and the increase in the healthy lifespan of aged mice by oral administration of Video abstractThe online version contains supplementary material available at 10.1186/s40168-021-01189-5. Health span is determined by the interactions between genetic and environmental factors , 2. In pAkkermansia muciniphila (AK) induces mucus production in the gut, which is critical for supporting intestinal integrity and other beneficial symbioses  or aged  mice were systemically treated with serum (100 μL per mouse) isolated from young mice by intravenous injection into the tail vein eight times (for 3 weeks) or sixteen times (for 6 weeks).Young ; (ii) hetero-chronic including hetero-young  and hetero-aged ; and (iii) iso-aged . After the suturing procedure, the mice were monitored daily for 6 weeks for signs of pain and distress. Body weight was recorded once per week. Circulatory exchange between parabiotic pairs was confirmed by injecting Evans blue dye /), and filtered through a strainer. Antibodies were purchased from BD Biosciences or BioLegend. BM cells were stained as previously described ; DAT, D-alanine transaminase [EC:2.6.1.21]; glutaryl-CoA dehydrogenase [EC:1.3.8.6]; lysine 2,3-aminomutase [EC:5.4.3.2]; beta-lysine 5,6-aminomutase [EC:5.4.3.3]; trans-2-enoyl-CoA reductase [EC:1.3.1.38]; acyl-CoA thioesterase YciA [EC:3.1.2.-]; PRPP, phosphoribosyl pyrophosphate; phosphoribosyl-ATP pyrophosphohydrolase [EC:3.6.1.31]; phosphoribosyl-AMP cyclohydrolase [EC:3.5.4.19]; phosphoribosylformimino-5-aminoimidazole carboxamide ribotide isomerase [EC:5.3.1.16]; imidazoleglycerol-phosphate dehydratase [EC:4.2.1.19]; histidinol-phosphate aminotransferase [EC:2.6.1.9]; histidinol-phosphatase (PHP family) [EC:3.1.3.15]; histidinol dehydrogenase [EC:1.1.1.23]; histidine ammonia-lyase [EC:4.3.1.3]; urocanate hydratase [EC:4.2.1.49]; imidazolonepropionase [EC:3.5.2.7]; GAD, glutamate decarboxylase [EC:4.1.1.15]; pectinesterase [EC:3.1.1.11]; pectate lyase [EC:4.2.2.2]; pectate disaccharide-lyase [EC:4.2.2.9]; oligogalacturonide lyase [EC:4.2.2.6]; glucuronate isomerase [EC:5.3.1.12]; tagaturonate reductase [EC:1.1.1.58]; altronate hydrolase [EC:4.2.1.7]; mannonate dehydratase [EC:4.2.1.8]; fructuronate reductase [EC:1.1.1.57]; L-xylulokinase [EC:2.7.1.53]; 3-dehydro-L-gulonate-6-phosphate decarboxylase [EC:4.1.1.85]; L-xylulokinase [EC:2.7.1.53]; L-ribulokinase [EC:2.7.1.16]; L-arabinose isomerase [EC:5.3.1.4]; xylulokinase [EC:2.7.1.17]; L-xylulose reductase [EC:1.1.1.10]; aldehyde reductase [EC:1.1.1.21]; D-xylulose reductase [EC:1.1.1.9]; rhamnulokinase [EC:2.7.1.5]; rhamnulose-1-phosphate aldolase [EC:4.1.2.19]; FabD, [acyl-carrier-protein] S-malonyltransferase [EC:2.3.1.39]; FabH, 3-oxoacyl-[acyl-carrier-protein] synthase III [EC:2.3.1.180]; FabG, 3-oxoacyl-[acyl-carrier protein] reductase [EC:1.1.1.100]; FabZ, 3-hydroxyacyl-[acyl-carrier-protein] dehydratase [EC:4.2.1.59]; FabK, enoyl-[acyl-carrier protein] reductase II [EC:1.3.1.-]; FabL, enoyl-[acyl-carrier protein] reductase III [EC:1.3.1.-]; FabF, 3-oxoacyl-[acyl-carrier-protein] synthase II [EC:2.3.1.179]; FabB, 3-oxoacyl-[acyl-carrier-protein] synthase I [EC:2.3.1.41]; YciA, acyl-CoA thioesterase [EC:3.1.2.-]; GSR, glutathione reductase (NADPH) [EC:1.8.1.7]; phospholipid-hydroperoxide glutathione peroxidase [EC:1.11.1.12]; PepA, leucyl aminopeptidase [EC:3.4.11.1]; PepD; dipeptidase D [EC:3.4.13.-]; PepN; aminopeptidase N [EC:3.4.11.2]; glutamate--cysteine ligase [EC:6.3.2.2]; GAD, glutamate decarboxylase [EC:4.1.1.15]; 2-hydroxyglutarate dehydrogenase [EC:1.1.99.2]; glutaconate CoA-transferase [EC:2.8.3.12]; ptb; phosphate butyryltransferase [EC:2.3.1.19]; buk; butyrate kinase [EC:2.7.2.7]; trans-2-enoyl-CoA reductase [EC:1.3.1.38]; acyl-CoA thioesterase YciA [EC:3.1.2.-]. h, Schematic summary shows key metabolic differences between young and aged group based on relative gene abundance profiles. Host metabolism is influenced by γ-aminobutyric acid (GABA) neurotransmitter, affecting the brain (inducing satiety) GABA modulates inflammation. Fermentation of pectin by intestinal-specific bacteria produces butyrate. It affects host metabolism in several ways by acting on the G protein-coupled receptor (GPR) expressed by intestinal endocrine cells. Butyrate stimulates the release of glucagon-like peptide 1 (GLP-1) and peptide YY (PYY), affecting the pancreas (inducing insulin secretion) and brain (inducing satiety). Lipopolysaccharides (LPS) derived from the membrane of Gram-negative bacteria are pro-inflammatory compounds. AMUC_1100 derived from Akkermansia muciniphila improves intestinal barrier function by increasing goblet cell density and stimulating Toll-like receptor 2 (TLR2). AMUC_1100 exerts the beneficial effect on mucus layer regeneration, inflammation, and insulin sensitivity. Arrow heads indicate stimulation and bar heads indicate inhibition. Fig. S5. Parabiosis experiments restores intestinal function, canonical Wnt signalling target genes, and genes regulating ISC function. a, Verification of blood sharing between the parabiotic pairs using Evans blue. Representative photographs of the mice were taken at 0.5 and 24 h after the injection of Evans blue into the tail vein of one parabiont in a pair a week after surgery. The serum concentration of Evans blue in both mice in each pair was measured at 620 nm by spectrophotometry at 0, 0.5, 1, 24, and 48 h after injection. b, Gene expression profile of mucin in the colon. c, Gene expression profile of barrier-forming tight junction proteins in the colon. d–g, Quantitative real-time PCR analyses for expression of canonical Wnt signalling target genes and genes regulating ISC function in ageing, cage model, serum injection model and parabiosis model. Data are means ± SEMs . ab means not sharing a common letter are significantly different at P < 0.05. h, Representative Ki67-stained pictures. Scale bar, 25 μm. i, quantification of Ki-67 positive cells per crypt base columnar cell in the colon. Data are means ± SEM. . Fig. S6. Dynamics of α-diversity indices including (a) Shannon diversity, (b) observed OTU, (c) Faith's phylogenetic diversity, (d) Pielou's evenness indices among samples of the co-housing, parabiosis, and serum injection groups. Statistical analysis was performed using Kruskal-Wallis test, young (week 20) versus rejuvenated mice group ; aged (W100) versus rejuvenated mice group . Abbreviations: Co-Y, young mice from co-housing experiments; Co-A, aged mice from co-housing experiments; Hetero-Y, young mice from heterochronic pairs; Hetero-A, aged mice from heterochronic pairs; Iso-Y, young mice from isochronic young pairs; Iso-A, aged mice from isochronic aged pairs; iv 8 (Y→Y), young mice treated with serum isolated from young mice by intravenously into the tail vein 8 times; iv 16 (Y→Y), young mice treated with serum isolated from young mice by intravenously into the tail vein 16 times; iv 8 (Y→A), aged mice treated with serum isolated from young mice by intravenously into the tail vein 8 times; iv 16 (Y→A), aged mice treated with serum isolated from young mice by intravenously into the tail vein 16 times. Fig. S7. Gut microbiome alteration in several rejuvenation models. a–b, Principal coordinate analysis (PCoA) of β-diversity based (a) Jaccard distances, and (b) Bray-Curtis dissimilarity metric among samples of the co-housing (left), parabiosis (middle) and serum injection (right) groups of mice analysed . Each dot represents an individual mouse. c, Heatmap presenting the relative abundance (%) of the key prevalent bacterial taxa found in young and aged-mice. The red and blue genus indicates enriched bacterial taxa in young mice (W20) and aged mice (W100), respectively. Fig. S8. LEfSe analysis showing microbial genus that was significantly different in abundance between (a) young mice (W20) and Co-Y, (b) young mice and Hetero-Y, (c) Hetero-Y mice and Iso-Y, (d) Hetero-A and Iso-A, (e) aged mice and iv 16 (Y→A), (f) young mice and iv 8 (Y→Y), and (g) young mice and iv 16 (Y→Y). Abbreviations: Co-Y, young mice from co-housing experiments; Hetero-Y, young mice from heterochronic pairs; Hetero-A, aged mice from heterochronic pairs; Iso-Y, young mice from isochronic young pairs; Iso-A, aged mice from isochronic aged pairs; iv 8 (Y→Y), young mice treated with serum isolated from young mice by intravenously into the tail vein 8 times; iv 16 (Y→Y), young mice treated with serum isolated from young mice by intravenously into the tail vein 16 times; iv 16 (Y→A), aged mice treated with serum isolated from young mice by intravenously into the tail vein 16 times. Abbreviations: Co-Y, young mice from co-housing experiments; Co-A, aged mice from co-housing experiments; Hetero-Y, young mice from heterochronic pairs; Hetero-A, aged mice from heterochronic pairs; Iso-Y, young mice from isochronic young pairs; Iso-A, aged mice from isochronic aged pairs; iv 8 (Y→Y), young mice treated with serum isolated from young mice by intravenously into the tail vein 8 times; iv 16 (Y→Y), young mice treated with serum isolated from young mice by intravenously into the tail vein 16 times; iv 8 (Y→A), aged mice treated with serum isolated from young mice by intravenously into the tail vein 8 times; iv 16 (Y→A), aged mice treated with serum isolated from young mice by intravenously into the tail vein 16 times. Fig. S9. Parabiosis experiments induce corticosterone levels in plasma. Plasma corticosterone levels in (a) naïve mice (young and aged mice) and (b) heterochronic parabiotic paired mice. All data are means ± SEMs . Fig. S10. Taxonomic composition and difference during rejuvenation process determined by metagenomic sequencing. Several microbial genera were significantly different in abundance between (a) Co-A and aged, (b) Co-Y and young, (c) Hetero-A and aged, (d) Hetero-A and Iso-A, (e) Hetero-Y and Young, (f) iv 8 (Y→A) and aged, (g) iv 16 (Y→A) and aged, (h) iv 8 (Y→Y) and young, and (i) iv 16 (Y→Y) and young. Bacterial taxon showing a significant abundance of change  was only shown with average fold-change value at the genus level. Red and blue indicate significantly increased bacterial taxa in young mice of 16s rRNA sequencing data and mice of 16s rRNA sequencing data, respectively. The Benjamini and Hochberg's FDR control method was used to correct for multiple comparisons. Abbreviations: Co-Y, young mice from co-housing experiments; Co-A, aged mice from co-housing experiments; Hetero-Y, young mice from heterochronic pairs; Hetero-A, aged mice from heterochronic pairs; Iso-Y, young mice from isochronic young pairs; Iso-A, aged mice from isochronic aged pairs; iv 8 (Y→Y), young mice treated with serum isolated from young mice by intravenously into the tail vein 8 times; iv 16 (Y→Y), young mice treated with serum isolated from young mice by intravenously into the tail vein 16 times; iv 8 (Y→A), aged mice treated with serum isolated from young mice by intravenously into the tail vein 8 times; iv 16 (Y→A), aged mice treated with serum isolated from young mice by intravenously into the tail vein 16 times. Fig. S11. Rejuvenation-associated changes in microbial functional potential and metabolism. a, LEfSe analysis of metabolic pathways in colon microbiota during each rejuvenation procedure. The two columns on the left indicate logarithmic LDA scores categorised by KEGG pathways, comparing young group, Co-A, Iso-A, Hetero-A, iv 8 (Y→A), and iv 16 (Y→A) to the aged group. The last column on the right shows logarithmic LDA scores categorised by KEGG pathways, comparing Co-Y, Iso-Y, Hetero-Y, iv 8 (Y→Y), and iv 16 (Y→Y) to the young group. The red and blue names of pathways indicate enriched metabolic pathways in young mice and in aged mice, respectively. Only KEGG pathways differ significantly during each rejuvenation procedure. b–e, Shown horizontal bar plots indicate the fold-change of each enzyme involved in (b) pentose and glucuronate interconversions, (c) lysine degradation, (d) glutathione metabolism, and (e) fatty acid biosynthesis in young, Co-A, Hetero-A, iv8 (Y→A), iv16 (Y→A), Co-Y, Hetero-Y, iv8 (Y→Y), and iv16 (Y→Y). Red and blue KEGG reactions indicate high abundance in young mice and in aged mice, respectively. Abbreviations: Co-Y, young mice from co-housing experiments; Hetero-Y, young mice from heterochronic pairs; Hetero-A, aged mice from heterochronic pairs; Iso-Y, young mice from isochronic young pairs; Iso-A, aged mice from isochronic aged pairs; iv 8 (Y→Y), young mice treated with serum isolated from young mice by intravenously into the tail vein 8 times; iv 16 (Y→Y), young mice treated with serum isolated from young mice by intravenously into the tail vein 16 times; iv 16 (Y→A), aged mice treated with serum isolated from young mice by intravenously into the tail vein 16 times. The following genes are represented by enzyme name and EC number: OADH, 2-oxoglutarate dehydrogenase (OADH) [EC:2.3.1.61]; DAT, D-alanine transaminase [EC:2.6.1.21]; glutaryl-CoA dehydrogenase [EC:1.3.8.6]; lysine 2,3-aminomutase [EC:5.4.3.2]; beta-lysine 5,6-aminomutase [EC:5.4.3.3]; trans-2-enoyl-CoA reductase [EC:1.3.1.38]; acyl-CoA thioesterase YciA [EC:3.1.2.-]; GAD, glutamate decarboxylase [EC:4.1.1.15]; pectinesterase [EC:3.1.1.11]; pectate lyase [EC:4.2.2.2]; pectate disaccharide-lyase [EC:4.2.2.9]; oligogalacturonide lyase [EC:4.2.2.6]; glucuronate isomerase [EC:5.3.1.12]; tagaturonate reductase [EC:1.1.1.58]; altronate hydrolase [EC:4.2.1.7]; mannonate dehydratase [EC:4.2.1.8]; fructuronate reductase [EC:1.1.1.57]; L-xylulokinase [EC:2.7.1.53]; 3-dehydro-L-gulonate-6-phosphate decarboxylase [EC:4.1.1.85]; L-xylulokinase [EC:2.7.1.53]; L-ribulokinase [EC:2.7.1.16]; L-arabinose isomerase [EC:5.3.1.4]; xylulokinase [EC:2.7.1.17]; L-xylulose reductase [EC:1.1.1.10]; aldehyde reductase [EC:1.1.1.21]; D-xylulose reductase [EC:1.1.1.9]; rhamnulokinase [EC:2.7.1.5]; rhamnulose-1-phosphate aldolase [EC:4.1.2.19]; FabD, [acyl-carrier-protein] S-malonyltransferase [EC:2.3.1.39]; FabH, 3-oxoacyl-[acyl-carrier-protein] synthase III [EC:2.3.1.180]; FabG, 3-oxoacyl-[acyl-carrier protein] reductase [EC:1.1.1.100]; FabZ, 3-hydroxyacyl-[acyl-carrier-protein] dehydratase [EC:4.2.1.59]; FabK, enoyl-[acyl-carrier protein] reductase II [EC:1.3.1.-]; FabL, enoyl-[acyl-carrier protein] reductase III [EC:1.3.1.-]; FabF, 3-oxoacyl-[acyl-carrier-protein] synthase II [EC:2.3.1.179]; FabB, 3-oxoacyl-[acyl-carrier-protein] synthase I [EC:2.3.1.41]; YciA, acyl-CoA thioesterase [EC:3.1.2.-]; GSR, glutathione reductase (NADPH) [EC:1.8.1.7]; phospholipid-hydroperoxide glutathione peroxidase [EC:1.11.1.12]; PepA, leucyl aminopeptidase [EC:3.4.11.1]; PepD; dipeptidase D [EC:3.4.13.-]; PepN; aminopeptidase N [EC:3.4.11.2]; glutamate--cysteine ligase [EC:6.3.2.2]; GAD, glutamate decarboxylase [EC:4.1.1.15]; trans-2-enoyl-CoA reductase [EC:1.3.1.38]; acyl-CoA thioesterase YciA [EC:3.1.2.-]. Fig. S12. Administration of AK restores the expression of the canonical Wnt signalling target genes and ameliorates the senescence-related phenotype in haematopoietic system. a, Quantitative reverse transcription PCR (qRT-PCR) analyses for the expression of canonical Wnt signalling target genes and genes regulating ISC function. Data are presented as means ± SEMs . b, A representative fluorescence-activated cell sorting plot showing the frequencies of LT-HSCs, ST-HSCs, and MPPs among LSKs in the bone marrow of AK-treated and untreated aged mice. c, Percentages of LT-HSCs, ST-HSCs, and MPPs among LSKs. Data are presented means ± SEMs . d, Representative images and e, frequencies of neutrophils, T cells, and B cells in the blood of AK-treated and untreated aged mice. Data are presented as means ± SEMs . f, qRT-PCR analysis of the Icam1 mRNA purified from bone niches and lineage-negative and -positive cells of the aged mice treated with AK. Data are presented as means ± SEMs . Fig. S13. Effect of AK treatment in aged mice. a, Principal coordinate analysis (PCoA) of β-diversity based Jaccard distances and Bray-Curtis dissimilarity metric between AK-treated and untreated aged mice . The gut microbiome of AK-treated aged mice shows significant differences with control (Table S2). b, Taxonomic composition and difference determined by metagenomic sequencing. Microbial genera were significantly different in abundance between aged-AK and aged-vehicle groups. Bacterial taxon showing a significant abundance of change  was only shown with average fold-change value at the genus level. Red and blue indicate significantly increased bacterial taxa in young mice of 16s rRNA sequencing data and mice of 16s rRNA sequencing data, respectively. The Benjamini and Hochberg's FDR control method was used to correct for multiple comparisons. c, Analysis of differentially abundant microbial genus between AK-treated and untreated aged mice were analysed by LEfSe . d, LEfSe analysis of KEGG enzymes in colon microbiota between AK-treated and untreated aged mice. No metabolic pathway is enriched between aged-AK and aged-vehicle groups. e, Survival rate and f, body weight change of AK-treated and untreated aged mice. g, Schematic summary shows TLR 2 and Wnt signalling pathways can be activated via the high abundance of Akkermansia in the aged-AK group compared to the aged-vehicle group. Lipopolysaccharides (LPS) derived from the membrane of Gram-negative bacteria are pro-inflammatory compounds. AMUC_1100 derived from Akkermansia muciniphila improves intestinal barrier function by increasing goblet cell density and stimulating Toll-like receptor 2 (TLR2). AMUC_1100 exerts a beneficial effect on mucus layer regeneration, inflammation, and insulin sensitivity. Wnt signalling is involved in the development and renewal of intestinal epithelium and hematopoietic stem cells. Arrow heads indicate stimulation and bar heads indicate inhibition.Additional file 2: Table S1. Read statistics of 16s rRNA and metagenome sequencing.Additional file 3: Table S2. Alpha and beta diversity analysis of the analysed groups in this study.Additional file 4: Table S3. Taxa identified by LEfSe analysis in this study. "LogMaxMean" indicates the log of the highest-class average. "Enriched in" indicates the class with the highest mean if the taxa are discriminative. "LDA" indicates the logarithmic of the linear discriminant analysis (LDA) score. "P-value" indicates p-value of the pairwise Kruskal-Wallis test performed by LEfSe.Additional file 5: Table S4. Effect of parabiotic pairing on blood parameters.Additional file 6: Table S5. Relative abundance of phylotypes detected in ageing and rejuvenation samples.Additional file 7: Table S6. Relative abundance of phylotypes detected in AK administration samples.Additional file 8: Table S7. Frailty score used to develop a clinical frailty index in mice.Additional file 9: Table S8. Sequences of PCR primers used in this study.


The corrected table is shown here.Page 5: cas type IIA system and the type II restriction-modification system LmoJ3 (24) were negatively associated with nonpersistence” should read “In contrast, genes associated with the CRISPR-cas type IIA system and the type II restriction-modification system LmoJ3 (24) were associated with nonpersistence.”Page 11, line 10: “In contrast, genes associated with the CRISPR-Page 15: References 24 and 32 are interchanged. The correctly numbered references are as follows:Listeria monocytogenes strains. Appl Environ Microbiol 78:2623–2630. https://doi.org/10.1128/AEM.07203-11.24. Lee S, Ward TJ, Siletzky RM, Kathariou S. 2012. Two novel type II restriction-modification systems occupying genomically equivalent locations on the chromosomes of Listeria monocytogenes clones with enhanced virulence. Appl Environ Microbiol 83:e01189-17. https://doi.org/10.1128/AEM.01189-17.32. Lee S, Ward TJ, Jima DD, Parsons C, Kathariou S. 2017. The arsenic resistance-associated Listeria genomic island LGI2 exhibits sequence and integration site diversity and a propensity for three


Cladosporium species have attracted considerable interest because of their ability to produce a wide array of metabolites, including alkaloids, macrolides, diketopiperazines, pyrones, tetralones, sterols, phenolics, terpenes, lactones, and tetramic acid derivatives that possess versatile bioactivities. Moreover, they produce diverse enzymes with biotechnological and industrial relevance. This review gives an overview on the Cladosporium species derived from marine habitats, including their metabolites and bioactivities, as well as the industrial and biotechnological potential of these species. In the current review, 286 compounds have been listed based on the reported data from 1998 until July 2021. Moreover, more than 175 references have been cited.The marine environment is an underexplored treasure that hosts huge biodiversity of microorganisms. Marine-derived fungi are a rich source of novel metabolites with unique structural features, bioactivities, and biotechnological applications. Marine-associated  Cladosporium (Cladosporiaceae) is one of the largest genera of dematiaceous hyphomycetes [Cladosporium species are frequent airborne molds, which can be isolated from almost every environment and geographic location, because their small conidia are easily dispersed [C. herbarum, C. cladosporioides, and C. sphaerospermum are its three major species [C. fulvum is the causal agent of tomato leaf mold [C. sphaerospermum isolated from Glycine max roots which can promote its growth [Cladosporium species have the potential to be used in various industrial processes [Cladosporium species have attracted considerable interest because of their ability to produce a wide array of metabolites, including macrolides, pyrones, phenolics, alkaloids, diketopiperazines, terpenes, sterols, quinones, lactones, and tetramic acid derivatives. These metabolites possess versatile bioactivities such as anticancer, antimicrobial, antiviral, insecticidal, antifouling, anti-malarial, anti-hyperlipidemic, and α-glucosidase and protein tyrosine phosphatase inhibiton [Cladosporium species derived from a marine habitat, including the structures and bioactivities of the reported metabolites, as well as the industrial and biotechnological potential of these species  even in a non-marine environment [The polycyclic aromatic hydrocarbons (PAHs) are volatile pollutants that can cause various environmental pollutions such as oceanic and freshwater contamination, which can take place during storage, use, or transportation of crude oil and its products. PAHs inhalation or ingestion through contaminated food and airborne contaminants leads to serious health disorders such as endocrine disruption, cancer, and reproductive and birth problems . Therefoironment .C. cladosporioides using the Buescher and Furmanski procedure after 10-day incubation and precipitation with (NH4)2SO4 and benzoate buffer at pH 4.0 [Pectinases are hydrolytic enzymes that are accountable for the hydrolysis of pectins. They are commonly found in fungi, bacteria, and plants. They have remarkable importance in the food industry such as vegetables and fruits processing, wine production, and olive oil extraction, as well as coffee, cocoa, and tea fermentation. They are utilized in the beverage industry to produce high yields due to improving clarification and pressing of concentrated fruit juices . Bastos t pH 4.0 .Cladosporium sp. isolated from the Antarctic macroalgae Ascoseira mirabilis and Georgiella confuens produced agarase that may have industrial importance in the extraction of agar or its byproducts such as bioactive galactose and oligosaccharides exist in the algal biomass to be utilized as substrates of 3rd generation bioethanol [Agarases and carrageenases can decompose algal biomass, producing carrageenans and agars that are the major components of the red algae cell wall. Furthermore, agarases hydrolyze agar, resulting in oligosaccharides that are employed as food additives with beneficial influences on human health ,105. Addoethanol .Cladosporium sp. isolated from Antarctic marine sponge had high xylanase potential when grown on wheat bran and pure xylans at lower temperatures that is a feature of cold-active enzymes [Cladosporium sp. could be convenient for many biotechnological processes, utilizing moderate- to low-temperature processes, especially those in food industries [Cladosporium sp. derived from Antarctic sponge. XynA is highly active on xylans with high arabinose content. Moreover, it is the most thermolabile endo-xylanase reported from filamentous fungus. Therefore, it could be a good alternative in some biotechnological operations to avoid heating, thereby reducing the costs [Xylan, the main component of hemicelluloses in the plant cell walls, represents about one-third of all renewable organic carbon on earth. Xylanases hydrolyze xylan to oligosaccharides that are further degraded to xylose. The latter is utilized for xylitol and bioethanol production. Xylanases have remarkable biotechnological influence in developing eco-friendly technologies in the pulp and paper industry and in food and feed industries, and for generating chemicals and liquid fuels from lignocellulose ,108,109. enzymes . Therefodustries . Gil-Durhe costs .2O2-dependent glycoprotein that needs Mn2+ for oxidizing aromatic dyes and mono-aromatic phenols [2 reduction to H2O [C. cladosporioides CBMAI 857 isolated from the Brazilian cnidarian Palythoa variabilis produced ligninolytic enzymes  with particular response to the various conditions of salinity and carbon sources. It possessed high values of MnP and laccase activities under salinity , indicating the potential use of this fungus for industrial applications and bioremediation of high-salt contaminated sites [The three main lignin-hydrolyzing enzymes that have great potential for industrial applications are LiP (lignin peroxidase), MnP (manganese-dependent peroxidase), and Lac (laccase) . LiP is  phenols . Laccasen to H2O . C. claded sites .C. cladosporioides CBMAI-857 associated with the coral Palythoa caribaeorum was tested for its RBBR decolorizing potential. It had efficient dye decolorization potential (93%) after 12 days in both liquid and solid media [Cladosporium sp. associated with the seagrass Posidonia oceanica produced tannases and ligninolytic enzymes at high salt concentrations. Its laccase and peroxidase activity was evident by the degradation of RBBR and Amaranth Red dyes [RBBR (Remazol Brilliant Blue R) and polymeric dyes decolorization has been assigned as an effective screening method for the fungi ability to degrade recalcitrant pollutants, including aromatic compounds such as PAHs. It was demonstrated that marine-derived fungi are often more effective than terrestrial fungi in treating various colored effluents because they are better adapted to perform under extreme conditions such as high salinity . C. cladid media . FurtherRed dyes .C. herbarum ER-25 possessed a high invertase potential and removed melanoidins from molasses through bio-adsorption and biodegradation mechanisms by Lac and MnP in the non-sterilized medium than in sterilized one at 5.5 pH and 20 °C. Therefore, this cold-adapted fungus can be used for molasses de-colorization [Invertase is a β-fructo-furanosidase that catalyzes sucrose conversion into fructose and glucose, giving invert syrup. This invert syrup is utilized in the beverage and food industries as a humectant in non-crystallizing creams, candies, artificial honey, and jam preparation . Molasserization .C. sphaerospermum obtained from deteriorated seaweed Ulva through SSF (solid-state fermentation) produced cellulase that had saccharification potential of seaweed biomass using green seaweed Ulva fasciata. Therefore, this cellulase can be utilized for saccharification of cellulosic feedstock for bioethanol production from marine macro-algal feedstock [Cellulose is a main component of the plant material that is abundantly utilized for the production of alternative liquid fuels such as bioethanol. eedstock .Cladosporium sp. CBMAI 1237 isolated from Dragmacidon reticulatum, revealing the existence of ene-reductases [C. cladosporioides CBMAI-857 isolated from the Brazilian cnidarian Palythoa caribaeorum catalyzed the asymmetric bio-reduction of 1-(4-methoxyphenyl)ethanone to 1-(4-methoxyphenyl)ethanol [C. cladosporioides CBMAI-857 catalyzed the enantio-selective bio-reduction of different aromatic ketones at pH 7.0 and 32 °C [Biocatalysis is an eco-friendly process for renewable raw materials and clean energy production and for the remediation of environmental contaminants . Recentlductases . Additiond 32 °C .Cladosporium species are rich with diverse types of metabolites with varied structural features such as macrolides, fatty acids, pyrones, phenolics, alkaloids, diketopiperazines, terpenes, sterols, quinones, lactones, and tetramic acid derivatives. Their classification was carried out here according to the chemical nature. During our search, it was found that some of the reported metabolites had the same structures and molecular formulae with different nomenclature. On the other hand, some metabolites had the same names with different structures. Moreover, some metabolites did not have names, thus they are named here using the AUPAC system for nomenclature. Herein, the reported secondary metabolites from Cladosporium species, as well as their bioactivities have been discussed  of them are from C. sphaerospermum.Tetramic acids are five-membered heterocycles with a pyrrolidine-2,4-dione core that are formed by the fusion of polyketide units and amino acid . The terivatives . These sivatives . They arivatives ,128. Theivatives . Note th1, 2, 4, and 5) biosynthesized by C. sphaerospermum 2005-01-E3 obtained from deep-sea sludge had no activity towards influenza A H1N1 virus (3 exhibited anti-H1N1 activity (IC50 276.0 μM) in comparison to ribavirin (IC50 131.0 μM) [Mycobacterium tuberculosis in the disk diffusion method [2), C (3), F (5), and L (11) separated from C. sphaerospermum SW67 associated with Hydractinia echinat hydroid polyp were assessed for protection towards cisplatin-caused cell damage in LLC-PK1 cells [2 and 5 alleviated the LLC-PK1 cells damage induced by cisplatin (Conc. 25 µM). Compound 2 (Conc. 100 µM) recovered cell viability with 90.68% that was more than NAC , whereas 5 (Conc. 50 and 100 μM) increased cell viability by 77.65 and 85.60%, respectively. Thus, 2 may be a candidate for treating cisplatin-produced unwanted effects and/or to prohibited nephrotoxicity induced by anticancer drugs. It was proposed that the existence of the C-8 hydroxy group may be essential for the reno-protective effect towards cisplatin-produced toxicity in LLC-PK1 cells [The tetramic acid derivatives, cladosins A, B, D, and E (N1 virus . While 331.0 μM) . Moreoven method . MoreoveK1 cells . The co-K1 cells .5 and 6 from C. sphaerospermum 2005-01-E3 that did not have anti-influenza A H1N1, anticancer, and anti-tubercular, as well as no NF-κB inhibitory activities [C. sphaerospermum WBS017 isolated from Fritillaria unibracteata var. wabuensis [7–10) and cladodionen (13) were isolated from sediment-derived C. sphaerospermum L3P3 and evaluated for cytotoxic capacity towards PC-3, MGC-803, SH-SY5Y, and HCT-116 cell lines using SRB method and against K562 and HL-60 using MTT method  was inactive. The results revealed that the C-8 absolute configuration and aniline moiety were essential for activity [In 2015, by OSMAC (one strain many compounds) technique, Yu et al. separated compounds tivities . Note thabuensis . CladosiT method . Compounactivity  , compared to etoposide (IC50 ranged from 1.76 to 2.27 μM) [, and 30 . Compoun2.27 μM) .C. sphaerospermum EIODSF 008 isolated from the deep-sea sediment collected from the East Indian Ocean yielded tetramic acid derivatives 13 and 22–28 (13 had cytotoxicity (IC50 28.6 µM) towards the HL-60 cell line [E. coli, M. luteus, and B subtilis [13 showed cytotoxic capacity towards HL-60, HeLa, HCT-116, and MCF-7 cell lines (IC50 ranged from 9.1 to 19.1 μM), compared to ADR (adriamycin) (IC50 ranged from 0.02 to 0.67 μM). However, it did not have antibacterial activities (conc. 100 μg/mL) against B. subtilis, P. aeruginosa, C. perfringens, S. aureus, E. coli, and C. albicans [14–21, new tetramic acid derivatives, were purified from the sea-sediment derived Cladosporium sp. acetone extract by Huang et al. in 2018. Compounds 14–16 are unusual 3-acyltetramic acids, having at C-3 of the pyrrolidine-2,4-dione core, a six-membered lactone ring, and hexyl-enic alcohol chain. They showed no obvious AchEI activity in the modified Ellman’s enzyme assay [C. albicans and S. aureus in the broth micro-dilution method and no cytotoxic effect towards HL60, HepG-2, and MCF-7 cell lines in the CCK8 assay [nd 22–28 . They weell line . Additiosubtilis . Additioalbicans . Compounme assay . MoreoveK8 assay .Diketopiperazines (DKPs) are cyclic dipeptides, consisting of two amino acids with or without extra structural modifications in the DKPs nucleus . Their m32) and cyclo-(Phe-Pro) (33) were separated from the EtOAc extract of Cladosporium sp. F14 isolated from seawater and investigated for their anti-larval activity at conc. 50 µg/mL towards Bugula neritina and Balanus amphitrite larvae in the settlement inhibition assays [B. neritina settlement  and B. amphitrite settlement . Furthermore, 32 and 33 obviously prohibited L. hongkongensis growth , compared to streptomycin (MIC 250 µg/mL). The MICs of 33 towards Ruegeria sp. and M. luteus were 200 and 100 µg/mL, respectively, compared to streptomycin  [36) and B (37), and haematocin (38) purified from the sediment-derived Cladosporium sp. were moderately cytotoxic towards HepG2 cell line  [Cyclo-  . On the ctively) .Cladosporium species.Fungal alkaloids are nitrogen-containing metabolites that are derived from amino acid metabolism and the mevalonate pathway . Many st42–55, were separated from Cladosporium sp. PJX-41 isolated from mangrove and assessed for anti-H1N1 activity using CPE (cytopathic effect) inhibition assay , compared to ribavirin (IC50 87 μM), while 42–44, 46–48, 50, and 54 (IC50 100–150 μM) had weak activity [Cladosporium sp. associated with Chondria crassicualis red alga afforded 56 that exhibited antioxidant potential (ED50 82.0 µM) more than oxybenzone  as evident by their UV-A protecting potential [S. aureus and S. aureus with MICs 31.0, 62.5, and 62.5, µg/mL, respectively [58, 68, and 70 separated from C. oxysporum were assessed for anti-plasmodial potential towards chloroquine-sensitive Plasmodium falciparum 3D7 [58 (conc. 3.13 µg to 25.0 µg) had an anti-plasmodial effect (EC50 24.8 µM), while 68 and 70 displayed no activity (EC50 > 25.0 µM), compared to artesunate (EC50 0.074 μM) in the SYBR Green I assay. Further, 58 (conc. ranged from 6.25 µM to 50.0 µM for 24 h) was investigated for apoptotic effect on 3D7-plasmodia strain by measuring the parasite ΔΨm . It induced loss of ΔΨm, leading to the release of cytochrome C from mitochondria to the cytosol resulted in parasite apoptosis. Therefore, it may provide a scaffold to apoptotic death in the stages of P. falciparum development [58, 68, and 70 had no anti-buruli ulcer activity against Mycobacterium ulcerans (IC50 ˃ 10 µM), compared to rifampicin (IC50 ˂ 1 µM) in the Resazurin microtiter assay [The glyantrypine-type alkaloids, on assay . Compounactivity . The mycotential . Furtherectively . The quiarum 3D7  , compared to curcumin . However, they showed moderate activity versus LNCap and LNCap , in comparison to curcumin  in the MTT assay [Cladosporium sp. HNWSW-1 associated with the mangrove plant Ceriops tagal biosynthesized compounds 74–76 that were assessed for their cytotoxic and α-glycosidase inhibitory effects , whereas 76 revealed cytotoxic potential towards BEL-7042 and Hela cell lines  in the MTT assay.They had significant activity towards HepG-2 and MCF-7 (ICTT assay . Cladosp effects . Compoun76 exhibited α-glucosidase inhibitory activity (IC50 78.2 µM), compared to acarbose (IC50 275.7 µM) in the glucose oxidase method [77) separated from Cladosporium sp. TPU1507 derived from marine sponge was assessed for its inhibitory effect towards PTP1B (protein tyrosine phosphatase) and TCPTP (T-cell PTP), using an enzyme-based assay [50 48 and 54 μM, respectively), in comparison to oleanolic acid (IC50 0.9 μM) [78, from a gorgonian-derived Cladosporium sp. collected from the South China Sea. It (IC50 0.76–3.11 μM) exhibited significant cytotoxicity towards HeLa, P388, HT-29, and A549 cell lines [B. cereus, T. halophilus, S. epidermidis, S. aureus, E. coli, P. putida, N. brasiliensis, and V. parahaemolyticus [Cladosporium sp. SCNU-F0001 isolated from a mangrove plant yielded a novel lactam macrolide named cladospamide A (79) that was evaluated for cytotoxic effect (conc. 50 μM) versus MDA-MB-435, A549, HCT116, HepG2, and BT549 in the MTT method and for antimicrobial potential (conc. 100 μg/mL) towards S. aureus, B. subtilis, E. coli, Salmonella ATCC 14028, and P. aeruginosa. Unfortunately, it exhibited no noticeable activity [Additionally, e method . Cladosped assay . It had  0.9 μM) . Cao et ll lines . On the olyticus . Cladospactivity .80) and B (81) purified from Cladosporium sp. SCSIO z015 broth did not have an obvious anti-biofilm activity towards S. aureus, E. coli, and B. subtilis [The new cyano-containing alkaloids, cladosporins A , compared to ascorbic acid (IC50 4.9 µM). Besides, they showed moderate toxicity towards brine shrine naupalii , compared with toosendanin (LC50 21.2 µM) in the brine shrimp lethality assay [84 and 85 from Cladosporium sp. JS1-2 isolated from the mangrove Ceriops tagal collected in the South China Sea. Compound 84 moderately prohibited the growth of Helicoverpa armigera Hubner newly hatched larvae (IC50 100 μg/mL), compared to azadirachtin (IC50 25 μg/mL). Further, they showed moderate antibacterial potential versus S. aureus with MICs 12.5 and 25.0 μg/mL, respectively, compared with ciprofloxacin (MIC 0.39 μg/mL) [In the DPPH assay, they also had no activity (ICty assay . In 20199 μg/mL) .91), together with 88 and 89 were separated from Cladosporium sp. FT-0012 was obtained from Pohnpei Island, Federated State of Micronesia, and assessed for antimicrobial activity using paper disks at conc. 10 µg/disk , while 88 was active (IZD 14.0 mm and IC50 17.0 µg/mL) towards X. campestris pv. oryzae. Moreover, 91 prohibited P. oryzae and M. racemosus growth  [The term “macrolides” was first used to describe the natural antibiotics that have 12–16-membered macrocyclic lactone ring, functionalized by double bonds, and carrying different aminosaccharide and saccharide components . Among t µg/disk . Compounctively) .Cladosporium sp. F14 isolated from seawater yielded a nine-membered macrolide, 92 that had weak antibacterial potential towards M. smegmatis, E. coli, B. thuringiensis, S. aureus, and B. subtilis and weak cytotoxic potential toward A435, HeLa, K562, and A549 in the MTT method [C. herbarum isolated from Callyspongia aerizusa sponge yielded cladospolide B (89) and pandangolides 2–4 (95–97) that showed no antimicrobial potential versus S. aureus ATCC 25923, B. subtilis 168, E. coli ATCC 25922, and C. albicans in the agar plate diffusion assay [Cladosporium sp. IFB3lp-2 isolated from the mangrove forest of Hainan province of China yielded 88, 89, 93–96, 100, and 116 that had no significant activity against HCT-116, Coxsachievirus A16, A549, MD-MBA-231, HepG2, human enterovirus 71, A375, and SW1116 cell lines (conc. 20 µM) in the MTT assay [T method . C. herbon assay . MoreoveTT assay  , along with 89 that were evaluated for cytotoxic effect (conc. 50 μM) versus MDA-MB-435, A549, HCT116, HepG2, and BT549 in the MTT method and for antimicrobial potential (conc. 100 μg/mL) towards S. aureus, B. subtilis, E. coli, Salmonella ATCC 14028, and P. aeruginosa. Unfortunately, none of them exhibited noticeable activity [89 and 117–120 from a gorgonian-derived Cladosporium sp. collected from the South China Sea. They showed no cytotoxicity towards HeLa, P388, HT-29, and A549 cell lines [B. cereus, T. halophilus, S. epidermidis, S. aureus, E. coli, P. putida, N. brasiliensis, and V. parahaemolyticus. Compounds 117–119 exhibited antibacterial potential against all tested bacteria , however 89 and 120 had weak activity (MIC ˃ 25.0 μM) [93 and 115 separated from Cladosporium sp. F14 at conc. 50 µg/mL had no anti-larval activity towards both B. neritina and B. amphitrite larvae in the settlement inhibition assays [98 and 99 and a known analog 93 from the rice culture EtOAc extract of C. cladosporioides associated with Bruguiera gymnorrhiza. Their configuration was established using ECD, modified Mosher’s, and X-ray diffraction methods, as well as optical rotations to be 5R, 11R for 98; 11R for 99; and 3R, 5S, 11S for 93. They had weak AChEI activity (IC50 > 50 µM), in comparison to tacrine in the modified Ellman’s method [C. cladosporioides MA-299 obtained from the mangrove plant B. gymnorrhiza yielded 12-membered thio-macrolides 96 and 101–104 that were assessed for antimicrobial potential against E. tarda QDIO-2 and E. ictarda QDIO-9 (aquatic pathogens) and C. glecosporioides QDAU-2, B. sorokiniana QDAU-5, P. piricola Nose QDAU-15, and F. oxysporum f. sp. cucumerinum QDAU-8 (plant pathogenic fungi) in the microtiter plates assay. All metabolites revealed activity against C. glecosporioides (MIC 1 or 2 μg/mL), compared to amphotericin B (MIC 0.5 μg/mL). Moreover, 101 and 104 showed noticeable activity (MIC 1.0 μg/mL) towards with E. tarda and E. ictarda, respectively, compared to chloramphenicol (MIC 0.5 μg/mL), while 102 and 104 exerted obvious effectiveness (MIC 1.0 μg/mL) versus F. oxysporum f. sp. cucumerinum, compared to amphotericin B (MIC 0.5 μg/mL). The data revealed that sulfur substituent may influence the macrolides’ bioactivities [107–112 and the related formerly reported 93 and 101 isolated from mangrove-derived C. oxysporum HDN13-314 had no cytotoxic activity versus HCT-116, BEL-7402, HL-60, A549, L-02, HeLa, K562, MGC-803, MCF-7, PC-3, SH-SY5Y, and MDA-MB-231 (IC50 > 50 μM) [Additionally, activity . Cao et ll lines . Further25.0 μM) . The metn assays . In 2019tivities . The new> 50 μM)  , whereas 108 had the best effect (MIC 4 μg/mL) versus E. tarda [106) and G (108) and cladocladosin A (121), a macrolide with bicyclo 5/9-ring, were purified from C. cladosporioides MA-299 by Zhang et al. and assessed for antimicrobial effect versus various plant, human, and aquatic pathogenic microbes in the microtiter plates assay. All metabolites revealed activity (MIC ranging from 1.0 to 4.0 μg/mL) towards V. anguillarum and E. tarda (aquatic pathogenic bacteria) [Additionally, they exerted antibacterial activities versus the aquatic pathogens E. tarda . In 2020acteria) .108 and 121 exerted activity (MICs 4.0 μg/mL) towards H. maydis (plant-pathogenic fungus) and P. aeruginosa (aquatic-pathogenic bacterium), respectively [113 and 114, purified from Cladosporium sp. L037 isolated from the Okinawan marine brown alga Actinotrichia fragilis exhibited cytotoxic influence  towards L1210 murine lymphoma cells in the MTT assay [113 had antifungal potential against C. albicans, C. neoformans, A. niger, and N. crassa (MICs 8.4–16.7 µg/mL), whereas 114 exhibited antibacterial activity only towards M. luteus and inactive against the other microorganisms [Moreover, ectively . The newTT assay . Moreoverganisms .Butanolides and butenolides are five-membered γ-lactones which may also be regarded as furan derivatives. They are an important class of structural motifs often encountered in various natural metabolites and synthetic targets . They ha122), purified from a soft coral-associated fungus Cladosporium sp. TZP-29, together with the formerly isolated derivative 126 showed no cytotoxic effect towards A-549, SMMC-7721, and HeLa cells in the SRB method [126 isolated from Cladosporium sp. IFB3lp-2 exhibited no significant activity against HCT-116, Coxsachievirus A16, A549, MD-MBA-231, HepG2, human enterovirus 71, A375, and SW1116 cell lines (Conc. 20 µM) in the MTT assay [B. cereus, T. halophilus, S. epidermidis, S. aureus, E. coli, P. putida, N. brasiliensis, and V. parahaemolyticus  [126 displayed no anti-larval activity towards both B. neritina and B. amphitrite larvae in the settlement inhibition assays [E. ictarda and Cytospora mandshurica Miura (MIC 8 μg/mL) [123, 124, and 127 and the known analog 126 separated from C. cladosporioides were assessed for AChEI activity using modified Ellman’s method  [The newly separated C12-macrolide, cladospolide F  . Qi et an assays . Additios method . Only 12128, 130, and 141 isolated from Cladosporium sp. IFB3lp-2 EtOAc extract had no noticeable cytotoxicity versus HCT-116, Coxsachievirus A16, A549, MD-MBA-231, HepG2, human enterovirus 71, A375, and SW1116 cell lines (Conc. 20 µM) in the MTT assay [131 did not show any anti-larval activity towards both B. neritina and B. amphitrite larvae [132 did not have cytotoxic activity towards HCT-116, BEL-7402, HL-60, A549, L-02, HeLa, K562, MGC-803, MCF-7, PC-3, SH-SY5Y, and MDA-MB-231 (IC50 > 50 μM) [E. ictarda, E. tarda, and Cytospora glecosporioides (MICs ranging from 16 to 32 μg/mL) [129) separated from a soft coral-associated Cladosporium sp. TZP-29, together with the formerly isolated derivatives 130 and 131 had no cytotoxic effect towards A-549, SMMC-7721, and HeLa cells in the SRB method. Moreover, 129–131 with IC50 ranged from 7.1 to 13.1 µM remarkably reduced the accumulation of lipid elicited by oleic acid (OA) in the HepG2 liver cells, in comparison to lovastatin as determined by oil-red O staining and intracellular triglyceride (TG) and total cholesterol (TC) quantification (The seco-acids TT assay . Compoune larvae . Moreove> 50 μM) , while i2 μg/mL) . Cladospfication .133, 134, and 138 and new fatty acids 135–137, 139, and 140 isolated from C. cladosporioides OUCMDZ-187 obtained from the mangrove plant Rhizophora stylosa collected in Shankou, Guangxi Province of China showed no cytotoxic effects (IC50 > 50 μM) towards K562, A549, and HeLa cells in the SRB method [S. aureus CGMCC-1.2465, E. coli CGMCC-1.2389, E. aerogenes CGMCC-1.0876, P. aeruginosa CGMCC-1.1785, B. subtilis CGMCC-1.3376, and C. albicans CGMCC-2.2086 in the agar dilution method [Further, they exhibited potent lipid-lowering potential in HepG2 hepatocytes, revealing a promising anti-hyperlipidemic capacity . The newB method . Addition method .Tetralones comprise a bicyclic aromatic hydrocarbon and a ketone and are regarded as benzo-fused cyclohexanone derivatives. They played a substantial role as a starting material for the synthesis of a range of synthetic heterocyclic compounds and pharmaceuticals due to their potential reactivity and suitability . Additio152), a new dimeric tetralone bridged via C-C linkage, was separated from Cladosporium sp. KcFL6 derived from the mangrove plant Kandelia candel, together with 142–144 , in comparison to NS-398 and indomethacin [A. baumannii ATCC-19606, S. aureus ATCC-29213, E. faecalis ATCC-29212, A. hydrophila ATCC-7966, E. coli ATCC-25922, K. pneumonia ATCC-13883, Fusarium sp., F. oxysporum f. sp. cucumeris, F. oxysporum f. sp. niveum, A. niger, and R. solani in the disc diffusion assay [Cladosporone A , compared to trichostatin A in the trypan blue-cell viability assay [142 had a remarkable anti-proliferative potential towards SW480, HT-29, and CaCo-2, in particular towards HT-29. It was revealed that HT-29 cells exposure to 142 produced G1/S phase cell cycle arrest, assisted by a vigorous p21waf1/cip1 expression, a significant down-regulation of CDK4, CDK2, cyclin E, and cyclin D1, and repression of CDK4 and CDK2 kinase activity [waf1/cip1 expression and inducing degradation of β-catenin, as well as impairing TCF/β-catenin pathway as evident by reduced cyclin D1 and c-Myc transcription. Finally, it induced the expression of E-cadherin, therefore antagonizing invasion and metastasis [C. cladosporioides HDN14-342 isolated from marine sediments yielded tetralone derivatives 143, 145–147, 154, and 155 that were evaluated for cytotoxic activities towards HCT-116, HeLa, and A549 cell lines by SRB method and towards HL-60 and K562 cell lines by MTT method, in comparison to doxorubicin (IC50 0.2–0.8 µM). Compounds 146 and 147 were active towards K562, HeLa, and HCT-116 cell lines (IC50 ranging from 3.9 to 23.0 µM), while other metabolites had no activity (IC50 > 50.0 µM) [143 possessed no anti-allergic effect (IC50 > 200 µM) on RBL-2H3 cells, in comparison to loratadine (IC50 35.01 µM) using fluorometric assay [143) and cladosporols F-J (146 and 148–151) from the marine algal-derived C. cladosporioides EN-399 and evaluated their cytotoxic activities towards H446, A549, HeLa, L02, Huh7, LM3, SW1990, and MCF-7 using MTT assay. Note that 143, 148, and 149 displayed cytotoxic activities towards most of the tested cell lines with IC50 ranging from 1.0 to 20.0 μM. Notably, 149 had cytotoxic effect towards LM3, A549, and Huh7 cell lines , compared to cisplatin (IC50 1.3 μM for A549 and 9.1 μM for LM3) and fluorouracil (IC50 6.2 μM for Huh7), whereas 143 exhibited cytotoxic activity (IC50 4.0 μM) towards H446 cell line, compared to adriamycin (IC50 4.0 μM). These results revealed that the existence of dihydro-1,4-naphthoquinone nucleus was important for the activity  and C-4 methoxyl strengthened the activity (148 vs. 151) [Compounds activity . It was tastasis . C. clad50.0 µM) . In 2020vs. 151) .E. coli, A. hydrophila, S. aureus, E. tarda, P. aeruginosa, M. luteus, V. alginolyticus, V. parahemolyticus, V. harveyi, A. brassicae, F. oxysporum, G. graminis, C. gloeosporioides, and P. piricolav using micro-plate assay. Compounds 143, 146, and 148–151 showed inhibitory potential towards M. luteus, E. coli, and V. harveyi (MICs 4–128 μg/mL). None of them had activity (MIC > 128 μg/mL) towards other tested microbes [143 and 145 from Cladosporium sp. JS1-2 isolated from the mangrove Ceriops tagal collected in the South China Sea [145 prohibited the growth of Helicoverpa armigera Hubner newly hatched larvae (IC50 150 μg/mL), compared to azadirachtin (IC50 25 μg/mL) [S. aureus with MIC 6.25 and 1.56 μg/mL, respectively, compared with ciprofloxacin (MIC 0.39 μg/mL) [150 and 153 that exhibited quorum sensing inhibitory potential towards Chromobacterium violaceum CV026  in the well diffusion assay [156 had no observable cytotoxic activity towards SF-268, NCI-H460, MCF-7, and HepG-2 (conc. 100 μM) in the SRB assay [157, in addition to 156, 158, and 159 isolated Cladosporium sp. JJM22 associated with the mangrove plant C. tagal had no cytotoxic effect (IC50 > 10 μM) versus HeLa cell line in the MTT assay, compared to epirubicin [158 exhibited noticeable antibacterial potential towards S. aureus, B. cereus, E. coli, V. alginolyticus, V. parahemolyticus, and MR S. aureus (conc. 20 μM) [160) and previously reported -3,4,8-trihydroxy-1-tetralone (159) were isolated from a sediment-associated Cladosporium sp. HDN17-58  , compared to ciprofloxacin [Moreover, their antimicrobial potential was assessed versus microbes . Bai et hina Sea . Compoun5 μg/mL) . Further9 μg/mL) . Cladospon assay . NeverthRB assay . The newirubicin   . One newHDN17-58 . Note thfloxacin .Perylenequinones comprise a class of natural products characterized by an oxidized pentacyclic core. They are dark-colored pigments isolated from diverse sources such as mold species, plants, and aphids . They re161–164), were isolated from Cladosporium sp. KFD33  production by LPS (lipopolysaccharide) in RAW264.7 cells [Cladosporium sp. JJM22 yielded new naphthalene-chromane derivatives, cladonaphchroms A (169) and B (170), and related metabolites 165 and 168 that were assessed for antibacterial effectiveness versus S. albus ATCC-8799, E. coli ATCC-25922, B. subtilis ATCC-6633, Micrococcus tetragenus ATCC-13623, and M. luteus ATCC-9341, employing microplate assay. Compound 169 possessed significant potential against S. albus (MIC 1.25 µg/mL), compared to ciprofloxacin (MIC 0.6 µg/mL). Moreover, 169 and 170 demonstrated broad-spectrum antifungal activities (MICs 25.0–100.0 µg/mL) towards P. parasitica var. nicotianae, A. brassicicola, B. oryzae, C. capsici, C. paradoxa Moreau, and D. medusaea Nitschke, compared to pochloraz (MICs 12.5–50.0 µg/mL) [166 had no cytotoxic effect (IC50 > 10 μM) versus HeLa cell line in the MTT assay and no antibacterial activity towards S. aureus, B. cereus, E. coli, V. alginolyticus, V. parahemolyticus, and MR S. aureus (conc. 20 μM) in the microplate assay [.7 cells   . Wu et ate assay .Xanthones are secondary metabolites commonly reported from plants, fungi, and lichen . They arC. halotolerans GXIMD 02502 associated with the coral Porites lutea yielded compounds 171–177 that were evaluated for their cytotoxicity versus 22RV1 and C4-2B (prostatic cancer cell lines), as well as RWPE-1 . Among them, 171–173, 175, and 176 revealed notable cytotoxicity versus C4-2B and 22RV1 cells (inhibitions ranged from 55.8% to 82.1% at conc. 10 µM), whereas 176 was the potent one . On the other hand, they exhibited nearly no cytotoxic effect versus RWPE-1 cell (inhibition < 27% at conc. 10 µM) [. 10 µM)  , along with the new metabolite, malettinin E (181) from Cladosporium sp. strain KF501 isolated from the German Wadden Sea , whereas 179–181 exhibited weak antibacterial effect towards Xanthomonas campestris (IC50 28.3–37.9 μM), compared to chloramphenicol (IC50 2.1 μM) [Silber et al. reported the isolation of malettinins A–C (dden Sea . These m 2.1 μM) .Bisnaphthopyrones are dimers, belonging to naphthopyrones. They have C13 basic skeleton (C6-C4-C3) that consists of naphthalene and pyrone cores .182), and the formerly isolated viriditoxin (183) and viriditoxin derivatives (184 and 185) were separated the sediment associated C. cladosporioides (183 was firstly reported from Aspergillus viridinutans [183 was the most potent one (IC50 0.1 μM), however 182 and 184 had a cytotoxic effect . However, 185 was ineffective [S. aureus ATCC-29213, with 183 being the most effective (MIC 0.023 μM) [The new binaphthopyrone, cladosporinone (orioides . Note thdinutans . They weffective . Note th.023 μM) .188–190, 193, 200, 201, and 203 from Cladosporium sp. OUCMDZ-302 isolated from mangrove plant Excoecaria agallocha. They possessed no cytotoxic effect towards BEL-7402, A549, HeLa, K562, HL-60, and H1975 cell lines in the MTT and SRB methods. Whilst 201 and 203 showed radical scavenging activity against DPPH . None of these metabolites exhibited antimicrobial activities against E. coli, E. aerogenes, P. aeruginosa, B. subtilis, and C. albicans [192), had no α-glycosidase inhibitory effect and no cytotoxic activity towards SGC-7901, K562, Hela, and BEL-7042 cell lines in the MTT assay [186 and 205 displayed no cytotoxic effect (IC50 > 10 μM) versus HeLa cell line in the MTT assay, as well as no antibacterial potential towards S. aureus, B. cereus, E. coli, V. alginolyticus, V. parahemolyticus, and MR S. aureus (conc. 20 μM) in the microplate assay [C. halotolerans GXIMD 02502 associated with the coral Porites lutea yielded a new benzopyranone derivative, coniochaetone K (196) with unusual C-8 carboxyl, along with 194, 195, 197, and 198 that were evaluated for their cytotoxicity versus 22RV1, C4-2B, and RWPE-1 cell lines . On the other hand, they exhibited nearly no cytotoxic effect versus RWPE-1 and C4-2B cells [206 prohibited the growth of H. armigera Hubner newly hatched larvae (IC50 100 μg/mL), compared to azadirachtin (IC50 25 μg/mL) [S. aureus (MIC 6.25 μg/mL), compared with ciprofloxacin (MIC 0.39 μg/mL) [207) did not have obvious anti-biofilm activity towards S. aureus, E. coli, and B. subtilis [50 49.9 µM), compared to toosendanin (LC50 21.2 µM) in the brine shrimp lethality assay [210 possessed no anti-allergic effect (IC50 > 200 µM) on RBL-2H3 cells, in comparison to loratadine (IC50 35.01 µM) using fluorometric assay [211–213 were separated from C. herbarum isolated from the sponge Aplysina aerophoba  with mortality rates 85 and 75% and 80 and 65%, respectively, while 213 did not have any activity. Besides, 213 showed growth inhibitory activity towards Spodoptera littoralis larvae  [211–213 did not show any noticeable antimicrobial activity in the agar plate diffusion assay [Among them, 2B cells . Bai et 5 μg/mL) . Further9 μg/mL) . Cladospsubtilis . On the ty assay . Furtheric assay . α-Pyronerophoba . Compoun216 from C. cladosporioides that possessed no anti-allergic effect (IC50 > 200 µM) on RBL-2H3 cells, in comparison to loratadine (IC50 35.01 µM) using fluorometeric assay [C. tagal associated-fungus Cladosporium sp. JJM22 produced new cyclohexene derivatives, cladoscyclitols A–D (218–221) (219 (IC50 2.95 μM) revealed potent α-glucosidase inhibitory activity, compared to acarbose (IC50 2.35 μM) in the colorimetric assay [S. aureus ATCC-6538, E. coli ATCC-25922, B. cereu ATCC-6633, V. alginolyticus ATCC-3787, V. Parahemolyticus ATCC-17802, or MRSA CMCC-B-63303 in the micro-plate assay [223) and B (224), representing new azaphilone epimers, together with bicyclic diol (225) were separated from sea sediment-associated C. perangustum FS62 fungus. They had no observable cytotoxic activity towards SF-268, NCI-H460, MCF-7, and HepG-2 (Conc. 100 μM) in the SRB assay [In 2020, He et al. purified ic assay . The man218–221) . Compounic assay . On the te assay . Perangu233 and 235 showed DPPH radical scavenging activity , in comparison to ascorbic acid (IC50 3.29 µM). Further, none of these compounds had antimicrobial potential versus P. aeruginosa, E. aerogenes, B. subtilis, E. coli, and C. albicans [232, 238, and 249 were separated from EtOAc extract of Cladosporium sp. F14 isolated from seawater and investigated for their anti-larval activity (conc. 50 µg/mL) towards B. neritina and B. amphitrite larvae in the settlement inhibition assays [232 had weak larvae settlement inhibition towards B. neritina and B. Amphitrite, respectively, whereas 238 and 249 showed weak inhibitory effects towards B. amphitrite and B. neritina larvae, respectively. In another larval settlement bioassay, 232, 238, and 249 inhibited B. neritina larval settlement  and B. amphitrite larval settlement . The larval settlement EC50 values of 249 towards B. amphitrite and 232 towards B. neritina were less than the US Navy program established standard requirement (EC50 25.0 µg/mL), revealing the potential of 232 and 249 as antifouling agents [232 obviously prohibited L. hongkongensis growth (IZD 8 mm and MIC 80 µg/mL), compared to streptomycin (MIC 250 µg/mL) [239 isolated Cladosporium sp. JJM22 associated with the mangrove plant C. tagal had no cytotoxic effect (IC50 > 10 μM) versus HeLa cell line in the MTT assay, compared to epirubicin [In the DPPH assay, albicans . The metn assays   . The ribirubicin .S. aureus, B. cereus, E. coli, V. alginolyticus, V. parahemolyticus, and MR S. aureus (conc. 20 μM) in the microplate assay [240 (IC50 2.05 μM) revealed potent α-glucosidase inhibitory activity, compared to acarbose (IC50 2.35 μM) in the colorimetric assay [S. aureus ATCC-6538, E. coli ATCC-25922, B. cereus ATCC-6633, V. alginolyticus ATCC-3787, V. Parahemolyticus ATCC-17802, and MRSA CMCC-B-63303 in the microplate assay [Cladosporium sp. associated with Chondria crassicualis red alga resulted in the separation of a phenol derivative, clavatol (241) that exhibited antioxidant capacity (ED50 227.0 µM) more than oxybenzone  as evident by their UV-A protecting potential [S. aureus [242 and 243 exhibited no observable cytotoxic activity towards SF-268, NCI-H460, MCF-7, and HepG-2 (Conc. 100 μM) in the SRB assay [247) did not have obvious anti-biofilm activity towards S. aureus, E. coli, and B. subtilis [50 16.4 µM), compared with ascorbic acid (IC50 4.9 µM). Besides, it showed moderate toxicity towards brine shrine naupalii (LC50 81.4 µM), comparing with toosendanin (LC50 21.2 µM) in the brine shrimp lethality assay [Additionally, it exhibited no noticeable antibacterial potential towards te assay . The newic assay . On the te assay . Phytochsubtilis , while ity assay .248 separated from Cladosporium sp. TPU1507 derived from marine sponge and assessed for inhibitory effect towards PTP1B and TCPTP using enzyme-based assay [50 27 μM) that was 2-fold weaker than on PTP1B (IC50 11 μM) [250), separated from C. herbarum isolated from Callyspongia aerizusa had no activity towards A. salina and HL-60 human leukemia cell line [251 from Cladosporium sp. OUCMDZ-1635 possessed no cytotoxic effect towards MCF-7, HeLa, HCT-116, HeLa, HCT-116, K562, and HL-60. Furthermore, it did not show antibacterial activity (conc. 100 μg/mL) against B. subtilis, P. aeruginosa, C. perfringens, S. aureus, E. coli, and C. albicans [252) prohibited the growth of H. armigera Hubner newly hatched larvae (IC50 150 μg/mL), compared to azadirachtin (IC50 25 μg/mL) [S. aureus (MIC 25.0 μg/mL), compared with ciprofloxacin (MIC 0.39 μg/mL) [253) and acetyl Sumiki’s acid (254) exerted activity towards S. aureus and B. subtilis (IZDs 7 mm at conc. 5 µg/disk), whereas they had no activity towards C. albicans and E. coli [Compound ed assay . It show0 11 μM) . The newell line . In addi5 μg/mL) . Further9 μg/mL) . The fur E. coli .268) and six sterol derivatives: 256, 258, 260, 262, 263, and 267 from gorgonian-associated Cladosporium sp. WZ-2008-0042 [268 was reported in the same year by Pang et al. as new metabolites with the name cladosporisteroid B from Cladosporium sp. SCSIO41007 associated with Callyspongia sp. [50 values ranging from 0.11 to 0.17 µM) revealed antiviral activity against RSV  with therapeutic ratio (TC50/IC50) values ranging from 5.18 to 9.92, in comparison to ribavirin in the neuraminidase inhibition assay. This could be due to their binding to RSV GREs (glucocorticoid response elements) [268 had no noticeable antibacterial potential towards B. cereus, M. luteus, S. aureus, V. anguillarum E. coli, Shigella dysenteriae, B. subtilis, and V. Parahemolyticus, while 263 was moderately active (MIC 3.13 μM) towards S. dysenteriae [256, 261, 265, 266, and 268 separated from C. cladosporioides sea sediment-derived fungus possessed no anti-allergic effect on RBL-2H3 cells, in comparison to loratadine using fluorometeric assay [264) and new pregnanes, cladosporisteroid B (268) and cladosporisteroid C (269), along with 259, 265, and 270 from Cladosporium sp. SCSIO41007 isolated from Callyspongia sp. and assessed their antiviral activity towards EV71 and H3N2 using CCK-8 and CPE assays, respectively. Only, 268 (IC50 16.2 μM) had weak activity towards H3N2 compared to oseltamivir (IC50 34.0 nM). Moreover, they revealed no cytotoxic effect towards K562, MCF-7, and SGC-7901 in the CCK-8 assay [268 was purified from C. sphaerospermum EtOAc fraction by HPLC with the aid of LCMS and assessed for its influence on adipogenesis and lipid metabolism during maturation of adipocyte  using 3T3-L1 preadipocytes [Adipsin (adipocyte marker gene) expression. Further, it significantly upregulated ATGL  and reduced FASN and SREBP1  expression. Collectively, 268 facilitated lipid metabolism and disrupted adipogenesis via promoting lipolysis and prohibiting lipogenesis [A study conducted by Yu et al. in 2018 led to the separation of a new pregnane; 3α-hydroxy-7-ene-6,20-dione  from the culture of Cladosporium sp. isolated from intertidal marine sediment [E. coli ATCC-25922, B. subtilis ATCC-6633, and C. albicans ATCC-18804 in the agar diffusion method. It is noteworthy that this class of metabolites had been reported formerly from red algae  [S,3S,4E)-hepta-4,6-diene-2,3-diol (285) and -Undeca-3,8,10-trien-1,6-diol (286) were assessed for cytotoxic potential versus HeLa, BEL-7402, HL-60, A549, K562, and H1975 cell lines. Compound 286 had a cytotoxic effect versus H1975 cell line (IC50 10.0 µM), compared to ADR (IC50 0.38 µM). While both metabolites revealed no antioxidant and antimicrobial capacities [Gallo et al. reported for the first time from fungi the isolation of α,β-unsaturated aldehydes  ,156. Thepacities .Cladosporium sp. isolate N5 associated with Porphyra yezoensis red alga did not produce any pathogenic symptoms in the reinfection assay. Further, its EtOAc extract displayed no lethality to A. salina and had a moderate antimicrobial activity which indicated that Cladosporium sp. had no toxicity to the aquatic ecosystem and could be applied as a biocontrol agent [Cladosporium sp. EIODSF 008 EtOAc extract exhibited significant antibacterial potential towards E. coli, M. luteus, and B. subtilis (conc. 100 µg/disc) [Cladosporium sp. EN-S01 isolated from Sargassum cinereum brown algae showed anticancer activity towards MCF-7, HeLa, and DU-145 cell lines . The extract had greater cytotoxic activity and anti-proliferative towards MCF-7 and HeLa cell lines than towards DU-145 [C. cladosporioides KT384175 isolated from the seaweed Sargassum wightii possessed remarkable antioxidant potential that was comparable to ascorbic acid, as well as significant Fe3+ reducing power that could be referred to its phenolic contents. Moreover, it revealed anti-angiogenic potential as evidenced by the decrease in the number and length of blood vessel branches on CAM  in-vivo in the CAM assay. Further, C. cladosporioides extract (conc. 1.0 mg/mL) had lower wound healing potential than thalidomide (conc. 1.0 µg/mL) in the in vitro scratch assay using MCF-7 cells [Cladosporium sp. F14 can produce antifouling and antibiotic metabolites in the existence of xylose or glucose. Significantly, it showed higher antibiotic activity towards M. luteus, P. piscida, Rhodovulum sp., Ruegeria sp., V. fluvialis, and V. harveyi in the existence of a sugar carbon source than in its absence in the disc diffusion assay, even though the fungal cells were well-grown under both conditions. Moreover, it possessed antifouling potential as it reduced the attachment of B. neritina (bryozoan larvae) in the larval settlement assay [C. cladosporioides isolated from the seaweed S. wightii possessed noticeable antimicrobial potential towards E. coli MTCC-118, B. subtilis MTCC-441, S. aureus MTCC-7443, P. aeruginosa MTCC-424, and A. niger MTCC-281 with the highest growth inhibition towards S. aureus (IZD 12 mm) and least activity against B. subtilis (IZD 9.5 mm), compared to ampicillin  in the well diffusion method. Furthermore, they also had significant antioxidant potential comparable to ascorbic acid in the DPPH assay and moderate effectiveness in reducing power assay [C. halotolerans biomass isolated from the marine debris collected around Tarout Island showed a significant free radical scavenging effect (%inhibition 78% within 30 min incubation) in the DPPH assay. Moreover, it exhibited cytotoxic potential towards MCF-7 (IC50 34.27 µL/mL), compared to cisplatin (IC50 17.69 µL/mL) in the MTT assay, as well as an antifungal effect against A. niger  in the broth dilution method [Ding et al. stated that ol agent . In the µg/disc) . The EtOs DU-145 . Moreove-7 cells . The seant assay . The goler assay . Ameen en method .C. phlei  and C. cucumerinum  were isolated mainly from plant sources [Cladosporium species [seco-acids, macrolides, diketopiperazines, alkaloids, and tetramic acid derivatives were reported mainly from marine-associated Cladosporium species.From the comprehensive review of the available literature, it was noticed that  sources ,164,165. sources ,165. Add species ,169,170.Cladosporium species are of biotechnological and industrial relevance and could be considered as substantial enzyme producers. Their enzymes are active in harsh conditions such as extremely low temperatures and high salinity. Therefore, they can be utilized in various industrial and biotechnological applications. Besides, these species were found to be a wealthy pool covering a wide array of metabolites with various bioactivities. Over the past 22 years, 286 metabolites have been separated from marine-associated Cladosporium species isolated from various marine samples, including mangrove, sediment, sponges, corals, gorgonians, algae, bivalves, hydroids, and others  and C. cladosporioides   .The results revealed that alkaloids, macrolides, tetramic acid and pyrone derivatives, and phenolics are the major metabolites reported from this marine-associated fungal species . They coAlthough the structural diversity of these metabolites, they were insufficiently evaluated for their bioactivities. Most of them had been assessed for their antimicrobial, cytotoxicity, antiviral, and insecticidal activities .However, there are limited studies that focus on the mechanism of action of these metabolites. Many of the tested metabolites possessed no noticeable efficacy in some of the tested activities. Therefore, estimation of other potential bioactivities and derivatization of these metabolites, as well as the mechanistic and in vivo studies of the active metabolites should clearly be the target of future research.Cladosporium species such as co-cultivation of organisms and elicitors epigenetic, as well as, modifiers can be applied [Growing evidence has revealed that the activation of silent gene clusters has the potential to significantly enhance the discovery of new natural metabolites of high-therapeutic leads. Different strategies to awake the silent biosynthetic gene clusters of  applied ,173,174. applied ,175. The applied ,172,173. applied . Challen applied ,172,177. applied ,172,173. applied ,172,178. applied .