Fungus Eutypella Sp Research Articles

Eutypetides A—E, Structurally Intriguing Polyketides Formed by Intramolecular [4+2] Cycloaddition from Marine‐Derived Fungus Eutypella sp. F0219

Comprehensive SummaryFour polycyclic ten‐membered lactones possessing unprecedented 10/6/5 tricyclic ring skeleton, named eutypetides A—D (1—4), and an intriguing polyketide containing a hexahydroisobenzofuran‐1(3H)‐one motif, named eutypetide E (5) were isolated from the marine‐derived fungus Eutypella sp. F0219, together with three new related biosynthetic polyketides eutypetides F—H (6—8). The absolute configurations of 1—5 were unequivocally determined by single‐crystal X‐ray diffraction analyses (Cu Kα), modified Mosher's method and electronic circular dichroism (ECD) calculations. Eutypetides G (7) showed remarkable anti‐inflammatory activity and could reduce the mRNA expression of proinflammatory cytokines IL‐1β, IL‐6, TNF‐α, and iNOS induced by LPS. Most notably, compounds 1—4 were formed biogenetically from 6—7 via the key intramolecular [4+2] cycloaddition, while compound 5 could be constructed biogenetically from 8 through the intramolecular [4+2] cycloaddition. All the above eight polyketides are proposed to originate from a C10 and a C6 fatty acid.

Natural linoleic acid from marine fungus Eutypella sp. F0219 blocks KEAP1/NRF2 interaction and ameliorates MASLD by targeting FABP4

Ectopic lipid accumulation induced lipotoxicity plays a crucial role in exacerbating the development of metabolic dysfunction-associated steatotic liver disease (MASLD), which affects over 30 % of the worldwide population and 85 % of the obese population. The growing demand for effective therapeutic agents highlights the need for high-efficacy lipotoxicity ameliorators and relevant therapeutic targets in the fight against MASLD. This study aimed to discover natural anti-lipotoxic and anti-MASLD candidates and elucidate the underlying mechanism and therapeutic targets. Utilizing palmitic acid (PA)-induced HepG-2 and primary mouse hepatocyte models, we identified linoleic acid (HN-002), a ligand of fatty acid binding protein 4 (FABP4), from the marine fungus Eutypella sp. F0219. HN-002 dose-dependently prevented lipid overload-induced hepatocyte damage and lipid accumulation, inhibited fatty acid esterification, and ameliorated oxidative stress. These beneficial effects were associated with improvements in mitochondrial adaptive oxidation. HN-002 treatment enhanced lipid transport into mitochondria and oxidation, inhibited mitochondrial depolarization, and reduced mitochondrial ROS (mtROS) level in PA-treated hepatocytes. Mechanistically, HN-002 treatment disrupted the interaction between KEAP1 and NRF2, leading to NRF2 deubiquitylation and nuclear translocation, which activated beneficial metabolic regulation. In vivo, HN-002 treatment (20 mg/kg/per 2 days, i. p.) for 25 days effectively reversed hepatic steatosis and liver injury in the fast/refeeding plus high-fat/high-cholesterol diet induced MASLD mice. These therapeutic effects were associated with enhanced mitochondrial adaptive oxidation and activation of NRF2 signaling in the liver. These data suggest that HN-002 would be an interesting candidate for MASLD by improving mitochondrial oxidation via the FABP4/KEAP1/NRF2 axis. The discovery offers new insights into developing novel anti- MASLD agents derived from marine sources.

Uncommon Epoxyquinols Pyrrolocytosporin A and Cytosporin E2 from the Fungus Eutypella sp. D-1.

Two uncommon epoxyquinols, pyrrolocytosporin A (1) and cytosporin E2 (2), along with the known cytosporin Y1 (3), were isolated from the solid defined medium of the Arctic-derived fungus Eutypella sp. D-1. Their structures were established through comprehensive analyses of spectroscopic and electronic circular dichroism data. Structurally, compound 1 represented the first nitrogen-containing epoxyquinol characterized by a pyrrole fused cytosporin framework, while compound 2 contained an uncommon cyclic carbonate functionality. The antibacterial, immunosuppressive, anti-inflammatory, and cytotoxic activities of all compounds were evaluated. Among the three metabolites, only compound 1 exhibited inhibitory effects on nitric oxide production induced by lipopolysaccharide with an IC50 value of 6.55 μM. Additionally, only compound 2 displayed inhibitory activity against ConA-induced T-cell proliferation with an IC50 value of 9.85 μM.

Ent-eudesmane sesquiterpenoids with anti-neuroinflammatory activity from the marine-derived fungus Eutypella sp. F0219

In this study, twenty-three ent-eudesmane sesquiterpenoids (1–23) including fifteen previously undescribed ones, named eutypelides A–O (1–15) were isolated from the marine-derived fungus Eutypella sp. F0219. Their planar structures and relative configurations were established by HR-ESIMS and extensive 1D and 2D NMR investigations. The absolute configurations of the previously undescribed compounds were determined by single-crystal X-ray diffraction analyses, modified Mosher's method, and ECD calculations. Structurally, eutypelide A (1) is a rare 1,10-seco-ent-eudesmane, whereas 2–15 are typically ent-eudesmanes with 6/6/-fused bicyclic carbon nucleus. The anti-neuroinflammatory activity of all isolated compounds (1−23) was accessed based on their ability to NO production in LPS-stimulated BV2 microglia cells. Compound 16 emerged as the most potent inhibitor. Further mechanistic investigation revealed that compound 16 modulated the inflammatory response by decreasing the protein levels of iNOS and increasing ARG 1 levels, thereby altering the iNOS/ARG 1 ratio and inhibiting macrophage polarization. qRT-PCR analysis showed that compound 16 reversed the LPS-induced upregulation of pro-inflammatory cytokines, including iNOS, TNF-α, IL-6, and IL-1β, at both the transcriptional and translational levels. These effects were linked to the inhibition of the NF-κB pathway, a key regulator of inflammation. Our findings suggest that compound 16 may be a potential structure basis for developing neuroinflammation-related disease therapeutic agents.

Eutypellaolides A–J, Sesquiterpene diversity expansion of the polar fungus Eutypella sp. D-1

Eight new 12,8-eudesmanolide sesquiterpenes, eutypellaolides A–H (1–8), and two new eudesmane-type sesquiterpenes, eutypellaolides I–J (9–10), along with four known 12,8-eudesmanolide compounds 11–14, were isolated from the culture extract of the polar fungus Eutypella sp. D-1 by one strain many compounds (OSMAC) approach. The structures of these compounds were determined through comprehensive spectroscopic data and experimental and calculated ECD analysis. Antibacterial, immunosuppressive, and PTP1B inhibition activities of these compounds were evaluated. Compounds 1 and 11 exhibited strong inhibitory activities against Bacillus subtilis and Staphylococcus aureus, with each showing an MIC value of 2 μg/mL. Compound 9 displayed weak immunosuppressive activity against ConA-induced T-cell proliferation with an inhibitory rate of 61.7% at a concentration of 19.8 μM. Compounds 5, 11, and 14 exhibited weak PTP1B inhibition activities with IC50 values of 44.8, 43.2, and 49.5 μM, respectively.

Pimarane-Type Diterpenes with Anti-Inflammatory Activity from Arctic-Derived Fungus Eutypella sp. D-1.

The Arctic-derived fungus Eutypella sp. D-1 can produce numerous secondary metabolites, and some compounds exhibit excellent biological activity. Seven pimarane-type diterpenes, including three new compounds eutypellenone F (1), libertellenone Y (2), and libertellenone Z (3), and four known compounds (4-7), were isolated from fermentation broth of Eutypella sp. D-1 by the OSMAC strategy of adding ethanol as a promoter in the culture medium. Compound 2 has a rare tetrahydrofuran-fused pimarane diterpene skeleton. The anti-inflammatory activity of all compounds was evaluated. Compounds 3-6 showed a significant inhibitory effect on cell NO release at 10 μmol/L by in vitro experiments, of which 3-5 had inhibitory rates over 60% on nitric oxide (NO) release. Subsequently, the anti-inflammatory activity of 3-5 was evaluated based on a zebrafish model, and the results showed that 3 had a significant inhibitory effect on inflammatory cells migration at 40 μmol/L, while 4 and 5 had a significant inhibitory effect at 20 μmol/L. Moreover, compounds 3-5 have the same conjugated double bond structure, which may be an important group for these compounds to exert anti-inflammatory activity.

Cytosporin Derivatives from Arctic-Derived Fungus Eutypella sp. D-1 via the OSMAC Approach.

A chemical investigation of the Arctic-derived fungus Eutypella sp. D-1 based on the OSMAC (one strain many compounds) approach resulted in the isolation of five cytosporin polyketides (compounds 1-3 and 11-12) from rice medium and eight cytosporins (compounds 2 and 4-11) from solid defined medium. The structures of the seven new compounds, eutypelleudesmane A (1), cytosporin Y (2), cytosporin Z (3), cytosporin Y1 (4), cytosporin Y2 (5), cytosporin Y3 (6), and cytosporin E1 (7), were elucidated by analyzing their detailed spectroscopic data. Structurally, cytosporin Y1 (4) may be a key intermediate in the biosynthesis of the isolated cytosporins, rather than an end product. Compound 1 contained a unique skeleton formed by the ester linkage of two moieties, cytosporin F (12) and the eudesmane-type sesquiterpene dihydroalanto glycol. Additionally, the occurrence of cyclic carbonate moieties in compounds 6 and 7 was found to be rare in nature. The antibacterial, immunosuppressive, and cytotoxic activities of all compounds derived from Eutypella sp. D-1 were evaluated. Unfortunately, only compounds 3, 6, 8, and 10-11 displayed immunosuppressive activity, with inhibitory rates of 62.9%, 59.5%, 67.8%, 55.8%, and 68.7%, respectively, at a concentration of 5 μg/mL.

Optimization of Protoplast Preparation and Establishment of Genetic Transformation System of an Arctic-Derived Fungus Eutypella sp.

Arctic-derived fungus Eutypella sp. D-1 has attracted wide attention due to its huge ability to synthesize secondary metabolites. However, current studies only focus on stimulating its production of new secondary metabolites by OSMAC strategies, and the relationship between secondary metabolites and biosynthetic gene clusters (BGCs) has not been explored. In this study, the preparation and regeneration conditions of Eutypella sp. D-1 protoplasts were explored to lay a foundation for the study of genetic transformation of this fungus. Orthogonal experiment showed that the optimal preparation conditions were 0.75 M NaCl, 20 g/L of lysing enzyme, and 20 g/L of driselase, 28°C for 6 h. The maximum yield of Eutypella sp. D-1 protoplasts could reach 6.15 × 106 cells·ml−1, and the concentration of osmotic stabilizer NaCl was the most important factor for Eutypella sp. D-1 protoplasts. The results of FDA staining showed that the prepared protoplasts had good activity. Besides, the best protoplasts regeneration medium was YEPS, whose maximum regeneration rate is 36%. The mediums with nitrogen sources, such as SR and RM, also had good effects on the Eutypella sp. D-1 protoplast regeneration, indicating that nitrogen sources played an important role on the Eutypella sp. D-1 protoplast regeneration. Subsequent transformation experiments showed that hygromycin resistance genes (hrg) could be successfully transferred into the genome of Eutypella sp. D-1, indicating that the prepared protoplasts could meet the needs of subsequent gene manipulation and research. This study lays a foundation for the genetic transformation of Eutypella sp. D-1.

The Mangrove-Derived Diterpenoid Diaporthe B Inhibits the Stemness and Increases the Efficacy of Docetaxel in Prostate Cancer PC-3 Cells

The absolute configuration of diaporthe B, a pimarane diterpene isolated from the mangrove derived endophytic fungus Eutypella sp #3E, was determined by a single-crystal x-ray diffraction study. The present study aimed to investigate the effects of diaporthe B on docetaxel-resistant prostate cancer PC-3 cells. Results of our studies showed that docetaxel-resistant PC-3 cells had higher sphere-forming efficiency and an increase in adherence to collagen-coated culture plates. The protein levels of cancer stem cell (CSC)-related markers CD44, CD133, and ALDH1A1 were higher in the docetaxel-resistant PC-3 cells than in the parental cells. Treatment with diaporthe B dose-dependently inhibited the growth and induced apoptosis in the resistant cells. Moreover, diaporthe B treatment decreased the sphere-forming efficiency and the adherence to collagen-coated plates in docetaxel-resistant PC-3 cells. Diaporthe B also decreased the protein levels of CSC-related markers CD44, CD133, and ALDH1A1 in the resistant cells. In addition, a combination of diaporthe B and docetaxel had a more potent effect on growth inhibition and apoptosis in the resistant cells than either agent alone. Our studies suggest that diaporthe B inhibits the stemness of prostate cancer cells and may have therapeutic potential for enhancing the efficacy of docetaxel in docetaxel-resistant prostate cancer cells.

Libertellenone H, a Natural Pimarane Diterpenoid, Inhibits Thioredoxin System and Induces ROS-Mediated Apoptosis in Human Pancreatic Cancer Cells.

Libertellenone H (LH), a marine-derived pimarane diterpenoid isolated from arctic fungus Eutypella sp. D-1, has shown effective cytotoxicity on a range of cancer cells. The present study is to explore the anticancer effect of LH on human pancreatic cancer cells and to investigate the intracellular molecular target and underlying mechanism. As shown, LH exhibited anticancer activity in human pancreatic cancer cells by promoting cell apoptosis. Mechanistic studies suggested that LH-induced reactive oxygen species (ROS) accumulation was responsible for apoptosis as antioxidant N-acetylcysteine (NAC) and antioxidant enzyme superoxide dismutase (SOD) antagonized the inhibitory effect of LH. Zymologic testing demonstrated that LH inhibited Trx system but had little effect on the glutathione reductase and glutaredoxin. Mass spectrometry (MS) analysis revealed that the mechanism of action was based on the direct conjugation of LH to the Cys32/Cys35 residue of Trx1 and Sec498 of TrxR, leading to a decrease in the cellular level of glutathione (GSH) and activation of downstream ASK1/JNK signaling pathway. Taken together, our findings revealed LH was a marine derived inhibitor of Trx system and an anticancer candidate.

Eutypellacytosporins A-D, Meroterpenoids from the Arctic Fungus Eutypella sp. D-1.

The Arctic fungus Eutypella sp. D-1, previously found to produce a variety of cytotoxic cyclopropyl-fused and cyclobutyl-fused pimarane diterpenoids when grown in the defined medium, was induced to produce unusual metabolites by growing on solid rice medium. A chemical investigation on the rice medium extract led to the isolation of four new meroterpenoids, eutypellacytosporins A-D (1-4), along with the known biogenetically related compound cytosporin D (5). The structures of the new compounds were elucidated by their detailed spectroscopic analysis and modified Mosher's method. Compounds 1-4 may be formed by the 12,32-ester linkage of two moieties, cytosporin D (5) and decipienolide A or B. All isolated compounds, except 5, showed weak cytotoxicity against DU145, SW1990, Huh7, and PANC-1 cell lines with IC50 values ranging from 4.9 to 17.1 μM.

Eremophilane-type sesquiterpenoids in a deep-sea fungus Eutypella sp. activated by chemical epigenetic manipulation

Cultivation of a deep-sea-derived fungus Eutypella sp. MCCC 3A00281 by a chemical epigenetic manipulation using suberohydroxamic acid (SBHA), a histone deacetylase inhibitor (HDI), resulted in the significant change of the metabolite profile. Chromatographic application of the extended metabolites led to the isolation of a total of 30 eremophilane-type sesquiterpenoids, of which 26 were identified as new entities namely eutyperemophilanes A-Z (1–26). Their structures were established by extensive analyses of the 1D and 2D NMR, and HRESIMS data, as well as the modified Mosher's method, X-ray crystallography, and ECD data for the assignment of their absolute configurations. Most eremophilanes from the fungal strain showed a trans-fusion of rings A and B, uncommonly found from nature. All compounds were evaluated for the inhibitory effects toward the nitric oxide (NO) production that was induced by lipopolysaccharide (LPS) in RAW 264.7 macrophage cells, while compounds 9 and 10 exerted significant inhibition.

Eutypellazines N−S, new thiodiketopiperazines from a deep sea sediment derived fungus Eutypella sp. with anti-VRE activities

Chemical investigation of a deep sea sediment derived fungus Eutypella sp. MCCC 3A00281 resulted in the isolation of six new thiodiketopiperazine alkaloids, namely eutypellazines N-S (1−6). Their structures were elucidated on the basis of the extensive NMR and mass spectroscopic analysis, including the ECD data for the determination of absolute configuration. The structures of eutypellazines N-P (1−3) were characteristic of unique spirocyclic skeletons, while eutypellazines N-O bearing a spirocyclic tetrahydrobenzothiophene motif were found from wide type fungus for the first time. The biogenetic generation of the spirocyclic skeletons was postulated. Compounds 3–5 exhibited inhibitory effects against vancomycin-resistant enterococci (VRE), suggesting that they may be the potential inhibitors toward drug resistant pathogenic bacteria after the structural modification.

A new hexahydrobenzopyran derivative from the gorgonian-derived Fungus Eutypella sp

A new hexahydrobenzopyran derivative cytosporin L (1), and another eight known compounds were isolated from the gorgonian-derived fungus Eutypella sp. collected from the South China Sea. The structure of 1 was elucidated by comprehensive spectroscopic data. The absolute configuration of 1 was determined by a chemical reaction and the modified Mosher’s method. The isolated secondary metabolites were evaluated for their antibacterial activities. Compound 1 showed antibacterial activity towards Micrococcus lysodeikticus and Enterobacter aerogenes with the same MIC values of 3.12 μM. Compounds 1–3 were evaluated for antiviral activities. Compounds 1 and 2 obviously inhibited the respiratory syncytial virus (RSV) with the IC50 values of 72.01 and 30.25 μM, respectively.

A new sesquiterpene lactone from fungus Eutypella sp. D-1

We isolated and identified a new sesquiterpene lactone which we named eut-Guaiane sesquiterpene (1), along with four cytochalasins from the fungus Eutypella sp. derived from the soil of high latitude of Arctic. The new structure was determined by spectroscopic studies such as 1D and 2D NMR and MS analyses, while the known compounds were identified by comparison of the NMR data with those in literatures. New compound 1 exhibited strong antibacterial activity against Escherichia coli, Bacillus subtilis and Staphylococcus aureus. Besides, it showed a little cytotoxicity against SGC7901 cell line.

Eutypellazines A–M, thiodiketopiperazine-type alkaloids from deep sea derived fungus Eutypella sp. MCCC 3A00281

Bioassay and NMR/MS guided fractionation resulted in the isolation of 13 new alkaloids from marine fungus Eutypella sp.

Cytotoxic pimarane-type diterpenes from the marine sediment-derived fungus Eutypella sp. FS46

Two new pimarane-type diterpenes, scopararanes H-I (1–2), along with five known ones (3–7) were isolated from the culture broth of a marine sediment-derived fungus Eutypella sp. FS46, which was obtained from the South China Sea. Their structures were established by extensive spectroscopic analysis. All of them were evaluated for their cytotoxic activities against MCF-7, NCI-H460 and SF-268 tumour cell lines. Scopararane I (2) showed moderate inhibitory activities.

Stimulatory effect of ethanol on libertellenone H biosynthesis by Arctic fungus Eutypella sp. D-1.

Libertellenone H (1) was a promising antitumor diterpenoid isolated from Arctic fungus Eutypella sp. D-1, however, its production was very limited. In this study, we investigated the effects of ethanol on cell growth and libertellenone H production. The mycelium in ethanol-feeding cultures was fragmented and dispersed, and the titer of libertellenone H was remarkably increased to 4.88 mg l(-1) in an optimal feeding manner, which was 16.4-fold higher than the control group. To provide an insight into the cell response to ethanol, genes critical to the libertellenone H biosynthesis were successfully cloned and their transcription levels were determined. The results suggested that the gene transcription levels of 3-hydroxy-3-methyl glutaric acyl coenzyme A reductase and geranylgeranyl diphosphate synthase were up-regulated by ethanol stimulation. The results from this study were helpful for further understanding of the ethanol function on diterpenes biosynthesis as well as developing more effective strategies for over-production of these desired secondary metabolites.

ChemInform Abstract: Bioactive Tyrosine‐Derived Cytochalasins from Fungus Eutypella sp. D‐1.

AbstractThree new cytochalasins Z24 (I), Z25 (II), and Z26 (III) are isolated along with the known compound, scoparasin B.

Bioactive tyrosine-derived cytochalasins from fungus Eutypella sp. D-1.

Three new cytochalasins Z24 , Z25 , Z26 (1-3, resp.) and one known compound, scoparasin B (4), were isolated from the fungus Eutypella sp. D-1 isolated from the soil of high latitude of the Arctic. The structures of 1-3 were elucidated from spectroscopic data (NMR, MS). These compounds were evaluated for cytotoxic activities against several human tumor cell lines. Among them, compound 1 exhibited moderate cytotoxicity toward human breast cancer MCF-7 cell line with IC50 of 9.33 μM.