New diarylcyclopentenone enantiomers and biphenyl derivatives from the fungus Talaromyces adpressus

Ten new compounds, including three pairs of diarylcyclopentenone enantiomers (±) talaromycesins A-C (1-3) and four biphenyl derivatives talaromycesins D-G (4-7), along with four known compounds (8-11), were isolated from the fungus Talaromyces adpressus. Their structures were determined by analyses of extensive NMR spectroscopic and HRESIMS data, and their absolute configurations were elucidated by the dimolybdenum tetraacetate [Mo2(AcO)4]-induced ECD spectra, X-ray crystallographic studies, and ECD calculations. These new compounds were evaluated for their immunosuppressive activities for the first time, and compound 7 probably exerted liver-protective and anti-inflammatory effects on Con A-induced AIH by decreasing the levels of inflammatory cytokines, modulating immune homeostasis, and decreasing hepatocyte apoptosis, which may become a potential drug for the treatment of autoimmune diseases.

Cytotoxic and Antibacterial Meroterpenoids Isolated from the Marine-Derived Fungus Talaromyces sp. M27416

Three novel meroterpenoids, taladrimanins B-D (1-3), were isolated from the marine-derived fungus Talaromyces sp. M27416, alongside three biogenetically related compounds (4-6). We delineated taladrimanin B's (1) structure using HRESIMS and NMR, confirmed its configuration via quantum chemical NMR analysis and DP4+ methodology, and verified it through X-ray crystallography. ECD calculations determined the absolute configuration of compound 1, while comparative NMR and ECD analyses elucidated the absolute configurations of 2 and 3. These compounds are drimane-type meroterpenoids with a C10 polyketide unit (8R-configuration). We proposed a biosynthetic pathway and noted that compound 1 showed cytotoxic activity against MKN-45 and 5637 cell lines and selective antibacterial effects against Staphylococcus aureus CICC 10384.

4-Hydroxy-2-pyridone derivatives with antitumor activity produced by mangrove endophytic fungus Talaromyces sp. CY-3

OSMAC strategy is a useful tool for discovering series of metabolites from microorganism. Five new sambutoxin derivatives (1-2, 4, 8-9), together with seven known compounds (3, 5-7, 10-12), were isolated from Talaromyces sp. CY-3 under OSMAC strategy and guidance of molecular networking. Their planar structures and absolute configurations were determined by NMR, HRESIMS, ECD spectra and common biosynthetic pathway. In bioassay, compounds 1-12 showed cytotoxicity to tumor cell lines with IC50 values in the range of 1.76-49.13 μM. The antitumor molecular mechanism of 10 was also explored. In vitro compound 10 significantly inhibited the growth and proliferation of two lung cancer cell lines (A549 and H1703). Furthermore, colony formation, EdU analysis, flow cytometry and Western blot analysis showed that 10 could induce cell cycle arrest in G0/G1 phase by promoting the expression of p53 and p21. The molecular mechanism of its antitumor effects in vitro is that 10 arrests the cell cycle by activating the p21/CyclinD1/Rb signaling pathway and the p53 pathway. Our results identified a lead small molecule compound with efficient antitumor growth and proliferation activity.

Talcarpones A and B: bisnaphthazarin-derived metabolites from the Australian fungus Talaromyces johnpittii sp. nov. MST-FP2594

Talcarpones A (1) and B (2) are rare bisnaphthazarin derivatives produced by Talaromyces johnpittii (ex-type strain MST-FP2594), a newly discovered Australian fungus, which is formally described and named herein. The talcarpones were isolated along with the previously reported monomeric naphthoquinone, aureoquinone (3), suggesting a biosynthetic link between these metabolites. Talcarpone A is a lower homologue of hybocarpone (4), which was first isolated from a mycobiont of the lichen Lecanora hybocarpa. The structures of 1 and 2 were elucidated by detailed spectroscopic analysis, molecular modelling and comparison with literature data. Talcarpones 1 and 2 exhibited moderate antifungal activity (MIC 0.78-3.1 µg ml-1) and weak activity against Gram-positive bacteria (MIC 13-25 µg ml-1). The talcarpones also demonstrated noteworthy chemical reactivities, with 2 converting rapidly to 1, which in turn converted slowly to the highly coloured 3. These post-biosynthetic reactions point to a potential ecological role for the talcarpones in providing ongoing (slow-release) physicochemical protection for T. johnpittii against solar irradiation.

Enantiomeric α-pyrone derivatives with immunosuppressive activity from Talaromyces adpressus

Five pairs of undescribed enantiomeric α-pyrone derivatives (±)-adprepyrones A-E (±1-±5), together with an unreported congener adprepyrone F (6), and 6-[(E)-3-Hydroxyprop-1-enyl]-4-methoxy-5-methyl-2-pyrone (7), recently reported as synthetic compound, were isolated from the fungus Talaromyces adpressus. Their structures with absolute configurations were elucidated by HRESIMS, 1D and 2D NMR, electronic circular dichroism calculations, and single-crystal X-ray diffraction analyses. (±)-Adprepyrone A (±1) possesses an unreported carbon skeleton formed by the fusion of an α-pyrone derivative with nicotinamide. Compounds (+)-2, (±)-4, (±)-5, and 7 showed moderate inhibitory activity against concanavalin A (ConA)-induced T lymphocyte proliferation with IC50 values ranging from 8.9 to 19.8 μM.

Benzoquinone and furopyridinone derivatives from the marine-derived fungus Talaromyces sp. MCCC 3A01752

Two new compounds, compounds 1 and 2, were obtained from the culture of a marine-derived fungus Talaromyces sp. MCCC 3A01752, together with 13 known compounds (3-15). Their structures were elucidated based on detailed analysis of NMR, HRESIMS, ECD spectra and OR value. Compound 1 exhibited antibacterial potential against Staphylococcus aureus with a MIC value of 100 μM and cytotoxic activity against gastric cancer cell line MKN1 with a IC50 value of 78.0 μM.

Antimicrobial polyketides from Magellan Seamount-derived fungus Talaromyces scorteus AS-242

Two new nonadride derivatives, namely, talarodrides G and H (1 and 2), and one new depsidone derivative, botryorhodine K (3), together with a known nonadride analogue (4), were characterized from the Magellan Seamount-derived fungus Talaromyces scorteus AS-242. Their structures were established by detailed interpretation of NMR spectroscopic and mass spectrometry data analysis. X-ray crystallographic analysis of compounds 1 and 3 confirmed their structures and absolute configurations, representing the first characterized crystal structure of a nonadride-type polyketide. The isolated compounds exhibited potent antimicrobial activities against the pathogenic bacterium MRSA and V. parahaemolyticus and pathogenic fungi C. gloeosporioides, F. oxysporum, and F. proliferatum, with MIC values ranging from 1 to 64 μg ml-1.

New Dipyrroloquinones from a Plant-Derived Endophytic Fungus Talaromyces sp

Two new dipyrroloquinones, namely talaroterreusinones A (1) and B (2), together with four known secondary metabolites, terreusinone A (3), penicillixanthone A (4), isorhodoptilometrin (5), and chrysomutanin (6), were isolated from the solid culture of the endophytic fungus Talaromyces sp. by integrating mass spectrometry-based metabolic profiling and a bioassay-guided method. Their planar structures and stereochemistry were elucidated by comprehensive spectroscopic analysis including NMR and MS. The absolute configuration at C-1″ of terreusinone A (1) was established by applying the modified Mosher's method. Compounds 1-6 were evaluated for anti-inflammatory activity and cytotoxicity. As a result, 1-3 inhibited the LPS-stimulated NO production in macrophage RAW264.7 cells, with IC50 values of 20.3, 30.7, and 20.6 µM, respectively. Penicillixanthone A (4) exhibited potent cytotoxic activity against Hep G2 and A549 cell lines, with IC50 values of 117 nM and 212 nM, respectively, and displayed significant antitumour effects in A549 cells by inhibiting the PI3K-Akt-mTOR signalling pathway.

New Meroterpenoid Derivatives from the Pomegranate-Derived Endophytic Fungus Talaromyces purpureogenus

In this study, we report the isolation of two new meroterpenoids, miniolutelide D (1) and miniolutelide E (13-epi-miniolutelide C) (2), along with two meroterpenoidal analogues (3 and 4) and two phenolic compounds (5 and 6) from the endophytic fungus Talaromyces purpureogenus derived from Punica granatum fruits. Their structures were elucidated using extensive MS, 1D, and 2D NMR spectroscopic analyses as well as by comparing with data in the literature. The absolute configurations of 1 and 2 were determined using TDDFT-ECD calculations. Antimicrobial activity was evaluated. Compound 5 displayed significant activity against methicillin-resistant Staphylococcus aureus strain ATCC 700699 and moderate activity against S. aureus strain ATCC 29213.

Retracted: Isolation and purifications of an ambuic acid derivative compound from marine algal endophytic fungi Talaromyces flavus that induces apoptosis in MDA-MB-231 cancer cells

In recent years, there has been a lot of buzz about the possibilities of marine microflora as a source of new therapeutic drugs. The strong anti-tumor potency of compounds found in marine resources reflects the ocean's enormous potential as a source of anticancer therapeutics. In this present investigation, an ambuic acid derivative anticancer compound was isolated from Talaromyces flavus, and its cytotoxicity and apoptosis induction potential were analyzed. T. flavus was identified through morphological and molecular analysis. The various organic solvent extracts of T. flavus grown on different growth mediums were evaluated for cytotoxicity on different cancer cell lines. The potent cytotoxicity was shown in the ethyl acetate extract of a fungal culture grown in the M1-D medium for 21 days. Furthermore, the anticancer compound was identified using preparative thin layer chromatography, followed by its purification in significant proportions using column chromatography. The spectroscopic and chromatographic analysis revealed that the structure of the purified molecules was an ambuic acid derivative. The ambuic acid derivative compound showed potent cytotoxicity on MDA-MB-231 (breast cancer cells) with an IC50 value of 26 μM and induced apoptosis in the MDA-MB-231 cells in a time-dependent and reactive oxygen species-independent manner.

Glyclauxins A-E: Dimeric Oxaphenalenone Aminoglycosides from an Australian Wasp Nest-Derived Fungus Talaromyces sp. CMB-MW102

Chemical analysis of cultures of a Queensland mud dauber wasp nest-derived fungus, Talaromyces sp. CMB-MW102, yielded the known dimeric oxaphenalenone duclauxin (1) along with a family of new 1-deoxy-d-glucosamine adducts, glyclauxins A-E (2-6). Despite 1D NMR spectra of 2-6 being compromised by broadening of selected resonances, structures inclusive of absolute configuration were assigned on the basis of detailed spectroscopic analysis and biogenetic considerations, as well as biomimetic semisynthesis and chemical interconversion. For example, exposure of duclauxin (1) to synthetic 1-deoxy-d-glucosamine yielded glyclauxin B (3), while on handling and storage, glyclauxins C (4) and D (5) (bearing a 7-OMe moiety) proved chemically labile and underwent quantitative transformation to glyclauxins B (3) and A (2), respectively. These latter observations on chemical reactivity and stability informed a proposed biogenetic relationship linking all known members of the extended duclauxin family. Notwithstanding their potential status as artifacts, the detection of glyclauxins B (3) and A (2) in a fresh CMB-MW102 culture extract confirmed their natural product status.

Isolation, structural determination, and antiviral activities of metabolites from vanitaracin A-producing Talaromyces sp

Vanitaracin A, an anti-hepatitis B virus polyketide, has been previously isolated from Talaromyces sp. In the present study, we searched for novel compounds in the culture broth obtained from a vanitaracin A-producing fungus under various conditions. Three novel compounds (vanitaracin C, vanitaraphilone A, and 2-hydroxy-4-(hydroxymethyl)-6-methylbenzaldehyde) were isolated, and their structures were determined using spectroscopic methods (1D/2D NMR and MS). In addition, the antiviral spectrum of vanitaracin A was examined by measuring its antiviral activities against rabies virus, Borna disease virus 1, and bovine leukemia virus. This compound exhibited antiviral activity against bovine leukemia virus, which is the causative agent of enzootic bovine leukosis. The anti-bovine leukemia virus effects of other compounds isolated from the vanitaracin A-producing fungus, namely, vanitaracins B and C, vanitaraphilone A, and 2-hydroxy-4-(hydroxymethyl)-6-methylbenzaldehyde, were also evaluated. Vanitaracin B, vanitaraphilone A and 2-hydroxy-4-(hydroxymethyl)-6-methylbenzaldehyde were also found to exhibit activity against bovine leukemia virus. These findings reveal the broad-spectrum antiviral activity of the vanitaracin scaffold and suggest several candidates for the development of anti-bovine leukemia virus drugs.

Two previously undescribed phthalides from Talaromyces amestolkiae, a symbiotic fungus of Syngnathus acus

Amestolkins A (1) and B (2), two previously undescribed phthalides sharing the same planar structure of (1, 5-dihydroxyhexyl)-7-hydroxyisobenzofuran-1(3H)-one were isolated from Talaromyces amestolkiae. Their absolute configurations were elucidated by comprehensive analyses of spectroscopic evidences in high-resolution electrospray mass spectra (HRESIMS) and nuclear magnetic resonance (NMR) combined with electronic circular dichroism (ECD) and NMR calculations. 1 and 2 showed anti-neuroinflammatory activity by inhibiting the gene expressions of proinflammatory factors including C-C motif chemokine ligand 2 (CCL-2), tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6), as well as attenuating the excretion of inducible nitric oxide synthase (iNOS) in BV-2 microglial cells at the concentration of 30 μM.

Talaropeptins A and B, Tripeptides with an N-trans-Cinnamoyl Moiety from the Marine-Derived Fungus Talaromyces purpureogenus CX11

We report the discovery of talaropeptins A (1) and B (2), tripeptides with an unusual 5/6/5 heterocyclic scaffold and an N-trans-cinnamoyl moiety, which were identified from the marine-derived fungus Talaromyces purpureogenus CX11. A bioinformatic analysis of the genome of T. purpureogenus CX11 and gene inactivation revealed that the biosynthesis of talaropeptins involves a nonribosomal peptide synthase gene cluster. Their chemical structures were elucidated using a combination of 1D and 2D NMR spectroscopy and mass spectrometry. The absolute configurations of 1 and 2 were established by electronic circular dichroism calculations and Marfey's method. The plausible biosynthesis of 1 and 2 is also proposed on the basis of gene deletion, substrate feeding, and heterologous expression. Compounds 1 and 2 showed moderate antifungal activity against phytopathogenic fungus Fusarium oxysporum with MIC values of 12.5 and 25 μg/mL, respectively.

Talarodrides A-F, Nonadrides from the Antarctic Sponge-Derived Fungus Talaromyces sp. HDN1820200

Six new nonadride derivatives, named talarodrides A-F (1-6), were isolated from the Antarctic sponge-derived fungus Talaromyces sp. HDN1820200. All structures including the absolute configurations were deduced by extensive spectroscopic analysis and computational ECD calculations. Compounds 1-4 share a rare caged bicyclo[4.3.1]-deca-1,6-diene with a bridgehead olefin and maleic anhydride core skeleton, while compounds 5 and 6 possess the first case of a naturally occurring 5/7/6 methanocyclonona[c]furan skeleton. Talarodride A (1) and talarodride B (2) showed selective inhibitory effects against Proteus mirabilis and Vibrio parahemolyticus with MICs of 3.13-12.5 μM.

Lytic Polysaccharide Monooxygenase from Talaromyces amestolkiae with an Enigmatic Linker-like Region: The Role of This Enzyme on Cellulose Saccharification

The first lytic polysaccharide monooxygenase (LPMO) detected in the genome of the widespread ascomycete Talaromyces amestolkiae (TamAA9A) has been successfully expressed in Pichia pastoris and characterized. Molecular modeling of TamAA9A showed a structure similar to those from other AA9 LPMOs. Although fungal LPMOs belonging to the genera Penicillium or Talaromyces have not been analyzed in terms of regioselectivity, phylogenetic analyses suggested C1/C4 oxidation which was confirmed by HPAEC. To ascertain the function of a C-terminal linker-like region present in the wild-type sequence of the LPMO, two variants of the wild-type enzyme, one without this sequence and one with an additional C-terminal carbohydrate binding domain (CBM), were designed. The three enzymes (native, without linker and chimeric variant with a CBM) were purified in two chromatographic steps and were thermostable and active in the presence of H2O2. The transition midpoint temperature of the wild-type LPMO (Tm = 67.7 °C) and its variant with only the catalytic domain (Tm = 67.6 °C) showed the highest thermostability, whereas the presence of a CBM reduced it (Tm = 57.8 °C) and indicates an adverse effect on the enzyme structure. Besides, the potential of the different T. amestolkiae LPMO variants for their application in the saccharification of cellulosic and lignocellulosic materials was corroborated.

Improving the Substrate Affinity and Catalytic Efficiency of β-Glucosidase Bgl3A from Talaromyces leycettanus JCM12802 by Rational Design

Improving the substrate affinity and catalytic efficiency of β-glucosidase is necessary for better performance in the enzymatic saccharification of cellulosic biomass because of its ability to prevent cellobiose inhibition on cellulases. Bgl3A from Talaromyces leycettanus JCM12802, identified in our previous work, was considered a suitable candidate enzyme for efficient cellulose saccharification with higher catalytic efficiency on the natural substrate cellobiose compared with other β-glucosidase but showed insufficient substrate affinity. In this work, hydrophobic stacking interaction and hydrogen-bonding networks in the active center of Bgl3A were analyzed and rationally designed to strengthen substrate binding. Three vital residues, Met36, Phe66, and Glu168, which were supposed to influence substrate binding by stabilizing adjacent binding site, were chosen for mutagenesis. The results indicated that strengthening the hydrophobic interaction between stacking aromatic residue and the substrate, and stabilizing the hydrogen-bonding networks in the binding pocket could contribute to the stabilized substrate combination. Four dominant mutants, M36E, M36N, F66Y, and E168Q with significantly lower K_m values and 1.4–2.3-fold catalytic efficiencies, were obtained. These findings may provide a valuable reference for the design of other β-glucosidases and even glycoside hydrolases.

Talaromynoids A-I, Highly Oxygenated Meroterpenoids from the Marine-Derived Fungus Talaromyces purpureogenus SCSIO 41517 and Their Lipid Accumulation Inhibitory Activities

Nine new highly oxygenated 3,5-dimethylorsellinic acid-derived meroterpenoids, talaromynoids A-I (1-9), were isolated from the marine-derived fungus Talaromyces purpureogenus SCSIO 41517. Their structures including absolute configurations were elucidated by HRMS, NMR, single-crystal X-ray diffraction analysis, and electronic circular dichroism calculations. Compounds 1 and 7-9 possessed unprecedented 5/7/6/5/6/6, 6/7/6/6/6/5, 6/7/6/5/6/5/4, and 7/6/5/6/5/4 polycyclic systems, respectively. Biologically, compound 5 showed selective inhibitory activity against phosphatase CDC25B with an IC₅₀ value of 13 μM. Moreover, 7-9 and 12 exhibited the activity of reducing triglyceride in 3T3-L1 adipocytes in a dosage-dependent manner.

Structural Insights into the Mechanisms Underlying the Kinetic Stability of GH28 Endo-Polygalacturonase

Thermostability is a key property of industrial enzymes. Endo-polygalacturonases of the glycoside hydrolase family 28 have many practical applications, but only few of their structures have been determined, and the reasons for their stability remain unclear. We identified and characterized the Talaromyces leycettanus JCM12802 endo-polygalacturonase TlPGA, which differs from other GH28 family members because of its high catalytic activity, with an optimum temperature of 70 °C. Distinctive features were revealed by comparison of thermophilic TlPGA and all known structures of fungal endo-polygalacturonases, including a relatively large exposed polar accessible surface area in thermophilic TlPGA. By mutating potentially important residues in thermophilic TlPGA, we identified Thr284 as a critical residue. Mutant T284A was comparable to thermophilic TlPGA in melting temperature but exhibited a significantly lower half-life and half-inactivation temperature, implicating residue Thr284 in the kinetic stability of thermophilic TlPGA. Structure analysis of thermophilic TlPGA and mutant T284A revealed that a carbon-oxygen hydrogen bond between the hydroxyl group of Thr284 and the Cα atom of Gln255, and the stable conformation adopted by Gln255, contribute to its kinetic stability. Our results clarify the mechanism underlying the kinetic stability of GH28 endo-polygalacturonases and may guide the engineering of thermostable enzymes for industrial applications.

Talascortenes A-G, Highly Oxygenated Diterpenoid Acids from the Sea-Anemone-Derived Endozoic Fungus Talaromyces scorteus AS-242

Eight new diterpenoid acids, namely, talascortenes A-G (1-7) and 5α,9β-dihydroxyisocupressic acid (8), with four different carbon skeletons, were isolated and identified from the endozoic fungal strain Talaromyces scorteus AS-242 that was obtained from the inner fresh tissue of a deep sea Cerianthus sp. sea anemone. The structures of the new compounds were elucidated by detailed interpretation of NMR and mass spectrometric data. X-ray crystallographic analysis of compounds 1-5 and 7 confirmed their structures and absolute configurations. Compounds 1-8 showed inhibitory activities against several human, aquatic, and plant pathogens with MIC values ranging from 1 to 32 μg/mL.

Crystal structure of GH30-7 endoxylanase C from the filamentous fungus Talaromyces cellulolyticus

GH30-7 endoxylanase C from the cellulolytic fungus Talaromyces cellulolyticus (TcXyn30C) belongs to glycoside hydrolase family 30 subfamily 7, and specifically releases 22-(4-O-methyl-α-D-glucuronosyl)-xylobiose from glucuronoxylan, as well as various arabino-xylooligosaccharides from arabinoxylan. TcXyn30C has a modular structure consisting of a catalytic domain and a C-terminal cellulose-binding module 1 (CBM1). In this study, the crystal structure of a TcXyn30C mutant which lacks the CBM1 domain was determined at 1.65 Å resolution. The structure of the active site of TcXyn30C was compared with that of the bifunctional GH30-7 xylanase B from T. cellulolyticus (TcXyn30B), which exhibits glucuronoxylanase and xylobiohydrolase activities. The results revealed that TcXyn30C has a conserved structural feature for recognizing the 4-O-methyl-α-D-glucuronic acid (MeGlcA) substituent in subsite -2b. Additionally, the results demonstrated that Phe47 contributes significantly to catalysis by TcXyn30C. Phe47 is located in subsite -2b and also near the C-3 hydroxyl group of a xylose residue in subsite -2a. Substitution of Phe47 with an arginine residue caused a remarkable decrease in the catalytic efficiency towards arabinoxylan, suggesting the importance of Phe47 in arabinoxylan hydrolysis. These findings indicate that subsite -2b of TcXyn30C has unique structural features that interact with arabinofuranose and MeGlcA substituents.

Bioactive Polyhydroxanthones from Penicillium purpurogenum

Eight new polyhydroxanthones, penicixanthones A-H (1-8), including four monomers (1-4) and four dimers (5-8), were isolated from solid cultures of Penicillium purpurogenum SC0070. Their structures were elucidated by extensive spectroscopic analysis, X-ray single-crystal diffraction, and theoretical computations of ECD spectra. Penicixanthone B (2) has a hexahydroxanthone structure featuring an unusual oxygen bridge between C-6 and C-8a. Penicixanthone D (4) is distinct from other penicixanthones in stereochemistry, and its biosynthetic mechanism was proposed based on theoretical simulations for the reaction pathway of C-10a epimerization. Penicixanthone G (6) exhibited the most potent cytotoxicity (IC₅₀: 0.3-0.6 μM) when tested against human carcinoma A549, HeLa, and HepG2 cells, whereas it was nontoxic to the normal Vero cells (IC₅₀ > 50 μM). It also displayed the strongest antibacterial activity (MIC: 0.4 μg/mL) against both Staphylococcus aureus and the methicillin-resistant strain MRSA.

Talarolactone A, an Isocoumarin Derivative Fused with Dihydrothiophene with Selective Antimigratory Activity from the Endolichenic Fungus Talaromyces sp

A 3,4-dihydroisocoumarin derivative fused with dihydrothiophene, talarolactone A (1), and two known compounds, terreusinone (2) and 4,6-dihydroxy-5-methylphthalide (3), were isolated from Talaromyces sp. associated with Xanthoparmelia angustiphylla. The structure of 1 was deduced from extensive spectroscopic data, electronic circular dichroism calculations, and X-ray diffraction analyses. A plausible biosynthetic pathway of 1 was further proposed. Compound 1 showed selective antimigratory activity in a wound-healing assay without appreciable cytotoxic activity.

Talauxins: Hybrid Phenalenone Dimers from Talaromyces stipitatus

Cultivation and extraction of the fungus Talaromyces stipitatus led to the isolation of five new oxyphenalenone-amino acid hybrids, which were named talauxins E, Q, V, L, and I based on the corresponding one-letter amino acid codes, along with their putative biosynthetic precursor, duclauxin. The rapid reaction of duclauxin with amino acids to produce talauxins was demonstrated in vitro and exploited to generate a small library of natural and unnatural talauxins. Talauxin V was shown to undergo spontaneous elimination of methyl acetate to yield the corresponding neoclauxin scaffold. This process was modeled using density functional theory calculations, revealing a dramatic change in conformation resulting from the syn elimination of methyl acetate.

Nonadride and Spirocyclic Anhydride Derivatives from the Plant Endophytic Fungus Talaromyces purpurogenus

Six new nonadride derivatives (1-6) and three new spirocyclic anhydride derivatives (7-9) were isolated from the endophytic fungus Talaromyces purpurogenus obtained from fresh leaves of the toxic medicinal plant Tylophora ovata. The structures of these compounds were determined by spectroscopic analyses including 1D and 2D NMR, HRESIMS, and ECD techniques. Maleic anhydride derivatives 1-9 were evaluated for their in vitro anti-inflammatory activities. Compound 1 showed significant inhibitory activity against NO production in LPS-induced RAW264.7 cells with an IC₅₀ value of 1.9 μM. Compounds 2 and 6 showed moderate inhibitory activities toward XOD and PTP1b, respectively, at 10 μM with inhibition rates of 67% and 76%.

Verruculosins A-B, New Oligophenalenone Dimers from the Soft Coral-Derived Fungus Talaromyces verruculosus

In an effort to discover new bioactive anti-tumor lead compounds, a specific tyrosine phosphatase CDC25B and an Erb family receptor EGFR were selected as drug screening targets. This work led to the investigation of the soft coral-derived fungus Talaromyces verruculosus and identification of two new oligophenalenone dimers, verruculosins A–B (1–2), along with three known analogues, bacillisporin F (3), duclauxin (4), and xenoclauxin (5). Compound 1 was the first structure of the oligophenalenone dimer possessing a unique octacyclic skeleton. The detailed structures and absolute configurations of the new compounds were elucidated on the basis of spectroscopic data, X-ray crystallography, optical rotation, Electronic Circular Dichroism (ECD) analysis, and nuclear magnetic resonance (NMR) calculations. Among which, compounds 1, 3, and 5 exhibited modest inhibitory activity against CDC25B with IC₅₀ values of 0.38 ± 0.03, 0.40 ± 0.02, and 0.26 ± 0.06 µM, respectively.

Comparative studies on Pb(II) biosorption with three spongy microbe-based biosorbents: High performance, selectivity and application

Lead pollution in industrial-derived water has become an increasingly serious concern. The development of adsorbents with excellent efficiency, selectivity and separability using diverse microorganisms is ideal for treating lead pollution. In this study, gram-negative bacteria Pseudomonas putida I3, gram-positive bacteria Microbacterium sp. OLJ1 and mycelial fungus Talaromyces amestolkiae Pb served as raw materials to facilely synthesize sponge-like biosorbents via a one-step method at room temperature. SEM, EDS, FTIR, ¹³C NMR, XRD and XPS were used for investigating the morphology and surface properties of these three biosorbents. The obtained biosorbents possessed the same three-dimensional porous structure but different productivities and mechanical strengths due to the similar chemical compositions and different cell structures of their microorganisms. Pb(II) adsorption on X-PI3, X-OLJ1 and X-TPb was fast and pH dependent, with maximal adsorption capacities of 345.02, 237.02 and 199.02 mg/g, respectively. The biosorbents had a high selectivity for Pb(II), while Pb(II) remarkably suppressed the adsorption of co-existing heavy metal ions. The analyses indicated that Pb(II) removal was mainly achieved by ion exchange reactions, surface complexation with heteroatom-containing functional groups and microprecipitation. The treatment effects of synthetic and real wastewater revealed that the as-prepared biosorbents are promising for Pb(II) removal.

Insight into the Thermophilic Mechanism of a Glycoside Hydrolase Family 5 β-Mannanase

To study the molecular basis for thermophilic β-mannanase of glycoside hydrolase family 5, two β-mannanases, TlMan5A and PMan5A, from Talaromyces leycettanus JCM12802 and Penicillium sp. WN1 were used as models. The four residues, His112 and Phe113, located near the antiparallel β-sheet at the barrel bottom and Leu375 and Ala408 from loop 7 and loop 8 of PMan5A, were inferred to be key thermostability contributors through module substitution, truncation, and site-directed mutagenesis. The effects of these four residues on the thermal properties followed the order H112Y > A408P > L375H > F113Y and were strongly synergetic. These results were interpreted structurally using molecular dynamics (MD) simulations, which showed that improved hydrophobic interactions in the inner wall of the β-barrel and the rigidity of loop 8 were caused by the outside domain of the barrel bottom and proline, respectively. The TIM barrel bottom and four specific residues responsible for the thermostability of GH5 β-mannanases were elucidated.

Funiculosone, a substituted dihydroxanthene-1,9-dione with two of its analogues produced by an endolichenic fungus Talaromyces funiculosus and their antimicrobial activity

An undescribed substituted dihydroxanthene-1,9-dione, named funiculosone, was isolated together with its two analogues identified as mangrovamide J and ravenelin, from the culture filtrates of Talaromyces funiculosus (Thom) Samson, Yilmaz, Frisvad & Seifert (Trichocomaceae), an endolichenic fungus isolated from lichen thallus of Diorygma hieroglyphicum (Pers.) Staiger & Kalb (Graphidaceae), in India. Funiculosone was characterized, essentially by spectroscopic methods, as 4,8,9a-trihydroxy-3,4a-dimethyl-4a,9a-dihydro-4H-xanthene-1,9-dione. Its relative stereochemistry was deduced by single crystal X-ray analysis while the absolute configuration was assigned as 4S,4aS,9aS by ECD spectra in comparison to that of the closely related mangrovamide J. This latter, to which, not being an amide, an inappropriate common name was given, was only recently isolated, together with undescribed and known prenylatedindole alkaloids and chromone derivatives from an unidentified Penicillium sp. X-ray structural analysis of the isolated mangrovamide J, for which no biological activity was previously reported, revealed polymorphism and a new crystalline phase is described. All the compounds displayed antibacterial activity with an IC₅₀ range 23-104 μg/mL when assayed against Escherichia coli Escherich and Staphylococcus aureus Ogston. Funiculosone also showed anticandidal activity against Candida albicans Berkhout with an IC₅₀ 35 μg/mL.

Celludinones, new inhibitors of sterol O-acyltransferase, produced by Talaromyces cellulolyticus BF-0307

New indanones, designated celludinones A ((±)-1) and B (2), were isolated from the culture broth of the fungal strain Talaromyces cellulolyticus BF-0307. The structures of celludinones were elucidated by spectroscopic data, including 1D and 2D NMR. Celludinone A was found to be a mixture of racemic isomers ((±)-1), which were isolated by a chiral column. Compounds (+)-1 and (-)-1 inhibited the sterol O-acyltransferase (SOAT) 1 and 2 isozymes in a cell-based assay using SOAT1- and SOAT2-expressing Chinese hamster ovary (CHO) cells, while 2 selectively inhibited the SOAT2 isozyme.

A Novel Thermostable GH3 β-Glucosidase from Talaromyce leycettanus with Broad Substrate Specificity and Significant Soybean Isoflavone Glycosides-Hydrolyzing Capability

A novel β-glucosidase gene (Bgl3B) of glycoside hydrolase (GH) family 3 was cloned from the thermophilic fungus Talaromyce leycettanus JM12802 and successfully expressed in Pichia pastoris. The deduced Bgl3B contains 860 amino acid residues with a calculated molecular mass of 91.2 kDa. The purified recombinant Bgl3B exhibited maximum activities at pH 4.5 and 65°C and remained stable at temperatures up to 60°C and pH 3.0-9.0, respectively. The enzyme exhibited broad substrate specificities, showing β-glucosidase, glucanase, cellobiase, xylanase, and isoflavone glycoside hydrolase activities, and its activities were stimulated by short-chain alcohols. The catalytic efficiencies of Bgl3B were 693 and 104/mM/s towards pNPG and cellobiose, respectively. Moreover, Bgl3B was highly effective in converting isoflavone glycosides to aglycones at 37°C within 10 min, with the hydrolysis rates of 95.1%, 76.0%, and 75.3% for daidzin, genistin, and glycitin, respectively. These superior properties make Bgl3B potential for applications in the food, animal feed, and biofuel industries.

Anti-inflammatory meroterpenoids from the mangrove endophytic fungus Talaromyces amestolkiae YX1

Four previously undescribed meroterpenoids, amestolkolides A-D, along with three known compounds were isolated from the mangrove endophytic fungus Talaromyces amestolkiae YX1 cultured on wheat solid-substrate medium culture. Their structures were elucidated by a combination of spectroscopic analyses. The absolute configurations of amestolkolides B and C, and purpurogenolide E were determined by single-crystal X-ray diffraction using Cu Kα radiation, and those of amestolkolides A and D were elucidated on the basis of experimental and calculated electronic circular dichroism spectra. The absolute configuration of amestolkolides A-D, and purpurogenolide E (9R) at C-9 was different from that of analogues (9S) in references, so that their plausible and distinct biosynthetic pathways were proposed. Amestolkolide B showed strong anti-inflammatory activity in vitro by inhibiting nitric oxide (NO) production in lipopolysaccharide activated in RAW264.7 cells with IC₅₀ value of 1.6 ± 0.1 μM.

Antimicrobial activity and acetylcholinesterase inhibition by extracts from chromatin modulated fungi

Major health challenges as the increasing number of cases of infections by antibiotic multiresistant microorganisms and cases of Alzheimer's disease have led to searching new control drugs. The present study aims to verify a new way of obtaining bioactive extracts from filamentous fungi with potential antimicrobial and acetylcholinesterase inhibitory activities, using epigenetic modulation to promote the expression of genes commonly silenced. For such finality, five filamentous fungal species (Talaromyces funiculosus, Talaromyces islandicus, Talaromyces minioluteus, Talaromyces pinophilus, Penicillium janthinellum) were grown or not with DNA methyltransferases inhibitors (procainamide or hydralazine) and/or a histone deacetylase inhibitor (suberohydroxamic acid). Extracts from T. islandicus cultured or not with hydralazine inhibited Listeria monocytogenes growth in 57.66±5.98% and 15.38±1.99%, respectively. Increment in inhibition of acetylcholinesterase activity was observed for the extract from P. janthinellum grown with procainamide (100%), when compared to the control extract (39.62±3.76%). Similarly, inhibition of acetylcholinesterase activity increased from 20.91±3.90% (control) to 92.20±3.72% when the tested extract was obtained from T. pinophilus under a combination of suberohydroxamic acid and procainamide. Concluding, increases in antimicrobial activity and acetylcholinesterase inhibition were observed when fungal extracts in the presence of DNA methyltransferases and/or histone deacetylase modulators were tested.

Lactones from the Sponge-Derived Fungus Talaromyces rugulosus

The marine-derived fungus Talaromyces rugulosus isolated from the Mediterranean sponge Axinella cannabina and cultured on solid rice medium yielded seventeen lactone derivatives including five butenolides (1–5), seven (3S)-resorcylide derivatives (6–12), two butenolide-resorcylide dimers (13 and 14), and three dihydroisocoumarins (15–17). Among them, fourteen compounds (1–3, 6–16) are new natural products. The structures of the isolated compounds were elucidated by 1D and 2D NMR (Nuclear Magnetic Resonance) spectroscopy as well as by ESI-HRMS (ElectroSpray Ionization-High Resolution Mass Spectrometry). TDDFT-ECD (Time-Dependent Density Functional Theory-Electronic Circular Dichroism) calculations were performed to determine the absolute configurations of chiral compounds. The butenolide-resorcylide dimers talarodilactones A and B (13 and 14) exhibited potent cytotoxicity against the L5178Y murine lymphoma cell line with IC₅₀ values of 3.9 and 1.3 µM, respectively.

Bioactive Azaphilone Derivatives from the Fungus Talaromyces aculeatus

Six new azaphilone derivatives, talaraculones A-F (1-6), together with five known analogues (7-11), were obtained from the saline soil-derived fungus Talaromyces aculeatus. The absolute configurations of 1 and 6 were assigned by quantum chemical calculations of the electronic circular dichroism (ECD) spectra. Compounds 1 and 5 represent the first reported azaphilone derivatives with a C4 aliphatic side chain and a methylal group at C-3, respectively. Talaraculones A and B (1 and 2) exhibited stronger inhibitory activity against α-glucosidase than the positive control acarbose (IC₅₀ = 101.5 μM), with IC₅₀ values of 78.6 and 22.9 μM, respectively.

Improving the Catalytic Performance of a Talaromyces leycettanus α-Amylase by Changing the Linker Length

A novel α-amylase, Amy13A, that consists of these domains was identified in Talaromyces leycettanus JCM12802: catalytic TIM-barrel fold, domain B, domain C, Thr/Ser-rich linker region, and C-terminal CBM20 domain. The wild type and three mutant enzymes were then expressed in Pichia pastoris GS115 to identify the roles of linker length (Amy13A21 and Amy13A33) and CBM20 (Amy13A-CBM) in catalysis. All enzymes had similar enzymatic properties, exhibiting optimal activities at pH 4.5-5.0 and 55-60 °C, but varied in catalytic performance. When using soluble starch as the substrate, Amy13A21 and Amy13A33 showed specific activities (926.3 and 537.8 units/mg, respectively, vs 252.1 units/mg) and catalytic efficiencies (k_cat/K_m, 25.7 and 22.0 mL s^-1 mg^-1, respectively, vs 15.4 mL s^-1 mg^-1) higher than those of the wild type, while Amy13A-CBM performed worse during catalysis. This study reveals the key roles of the CBM and linker length in the catalysis of GH13 α-amylase.

A New Ergosterol Analog, a New Bis-Anthraquinone and Anti-Obesity Activity of Anthraquinones from the Marine Sponge-Associated Fungus Talaromyces stipitatus KUFA 0207

A new ergosterol analog, talarosterone (1) and a new bis-anthraquinone derivative (3) were isolated, together with ten known compounds including palmitic acid, ergosta-4,6,8(14),22-tetraen-3-one, ergosterol-5,8-endoperoxide, cyathisterone (2), emodin (4a), questinol (4b), citreorosein (4c), fallacinol (4d), rheoemodin (4e) and secalonic acid A (5), from the ethyl acetate extract of the culture of the marine sponge-associated fungus Talaromyces stipitatus KUFA 0207. The structures of the new compounds were established based on extensive 1D and 2D spectral analysis, and in the case of talarosterone (1), the absolute configurations of its stereogenic carbons were determined by X-ray crystallographic analysis. The structure and stereochemistry of cyathisterone (2) was also confirmed by X-ray analysis. The anthraquinones 4a-e and secalonic acid A (5) were tested for their anti-obesity activity using the zebrafish Nile red assay. Only citreorosein (4c) and questinol (4b) exhibited significant anti-obesity activity, while emodin (4a) and secalonic acid A (5) caused toxicity (death) for all exposed zebrafish larvae after 24 h.

Talarofuranone, a New Talaroconvolutin Analog from the Endophytic Fungus Talaromyces purpurogenus from Pouteria campechiana Seeds

An endophytic fungus Talaronyces pinpurogenus was isolated from the seeds of the popular edible fruit Pouteria campechiana. The fungus was fermented in potato dextrose agar and the fungal media were extracted with EtOAc. Chromatographic separation of the EtOAc extracts over silica gel, Sephadex LH-20 and preparative thin layer chromatography furnished a furanone analogue of talaroconvolutin A, named talarofuranone (1), along with talaroconvolutin A (2), 4-hydroxyactophenone, tyrosol and ergosterol. The structure of 1 was determined by comparing the NMR data with that of 2 and by HRFABMS.

Talarazines A-E: Noncytotoxic Iron(III) Chelators from an Australian Mud Dauber Wasp-Associated Fungus, Talaromyces sp. (CMB-W045)

Chemical analysis of an Australian mud dauber wasp-associated fungus, Talaromyces sp. (CMB-W045), yielded five new coprogen siderophores, talarazines A-E (1-5), together with dimerumic acid (6), desferricoprogen (7), and elutherazine B (8). Structures inclusive of absolute configuration were assigned on the basis of detailed spectroscopic analysis and application of the C₃ Marfey's method. We report on the noncytotoxic Fe(III) chelation properties of 1-8 and demonstrate that biosynthesis is regulated by available Fe(III) in culture media. We demonstrate a magnetic nanoparticule approach to extracting high-affinity Fe(III) binding metabolites (i.e., 8) from complex extracts.

Antimicrobial Oligophenalenone Dimers from the Soil Fungus Talaromyces stipitatus

New polyketide-derived oligophenalenone dimers, 9a-epi-bacillisporin E (1) and bacillisporins F-H (2-5), along with the known bacillisporin A (6), were isolated from the fungus Talaromyces stipitatus. Their structures and absolute configurations were determined on the basis of spectroscopic analyses, electronic circular dichroism, and GIAO NMR shift calculation followed by DP4 analysis. The antimicrobial activity of these compounds was evaluated against a panel of human pathogenic bacteria. Among them, bacillisporin H (5) exhibited antimicrobial activity together with modest cytotoxicity against HeLa cells.

Three Pairs of New Isopentenyl Dibenzo[b,e]oxepinone Enantiomers from Talaromyces flavus, a Wetland Soil-Derived Fungus

Three pairs of new isopentenyl dibenzo[b,e]oxepinone enantiomers, (+)-(5S)-arugosin K (1a), (−)-(5R)-arugosin K (1b), (+)-(5S)-arugosin L (2a), (−)-(5R)-arugosin L (2b), (+)-(5S)-arugosin M (3a), (−)-(5R)-arugosin M (3b), and a new isopentenyl dibenzo[b,e]oxepinone, arugosin N (4), were isolated from a wetland soil-derived fungus Talaromyces flavus, along with two known biosynthetically-related compounds 5 and 6. Among them, arugosin N (4) and 1,6,10-trihydroxy-8-methyl-2-(3-methyl-2-butenyl)-dibenz[b,e]oxepin-11(6H)-one (CAS: 160585-91-1, 5) were obtained as the tautomeric mixtures. The structures of isolated compounds were determined by detailed spectroscopic analysis. In addition, the absolute configurations of these three pairs of new enantiomers were determined by quantum chemical ECD calculations.

Talarolutins A-D: Meroterpenoids from an endophytic fungal isolate of Talaromyces minioluteus

Four meroterpenoids [talarolutins A-D] and one known compound [purpurquinone A] were characterized from an endophytic fungal isolate of Talaromyces minioluteus (G413), which was obtained from the leaves of the medicinal plant milk thistle [Silybum marianum (L.) Gaertn. (Asteraceae)]. The structures of talarolutins A-D were determined by the analysis of various NMR and MS techniques. The relative and absolute configuration of talarolutin A was determined by X-ray diffraction analysis. A combination of NOESY data and comparisons of ECD spectra were employed to assign the relative and absolute configuration of the other analogs. Talarolutins B-D were tested for cytotoxicity against human prostate carcinoma (PC-3) cell line, antimicrobial activity, and induction of quinone reductase; no notable bioactivity was observed in any assay.

New Isocoumarins and Related Metabolites from Talaromyces flavus

Two new isocoumarin derivatives, talaisocoumarins A (1) and B (2), and three new related metabolites, talaflavuols A-C (3-5) were isolated from the wetland soil-derived fungus Talaromyces flavus BYD07-13. Their structures were elucidated by spectroscopic (NMR) and MS analyses. The absolute configurations of 1 and 2 were determined by CD and an Rh2(OCOCF3)4-induced CD method. All compounds were evaluated for cytotoxic and antimicrobial activities. However, none of them showed any activity. The plausible biosynthetic pathways for 1-5 were also proposed.

Secondary Metabolites from the Culture of the Marine Sponge-Associated Fungi Talaromyces tratensis and Sporidesmium circinophorum

Wortmin (1), meso-1,4-bis(4-methoxybenzyl)-2,3-butanediol (2), and a new isocoumarin derivative tratenopyrone (3) were isolated from the marine sponge-associated fungus Talaromyces tratensis KUFA 0091. A new diphenyl ether derivative, circinophoric acid (4), was isolated, together with the previously reported anthraquinones catenarin and physcion, the benzophenone monomethylsoluchrin, and β-ergosterol-5,8-endoperoxide, from the marine sponge-associated fungus Sporidesmium circinophorum KUFA 0043. The structures of the new compounds were established based on an extensive analysis of 1D and 2D NMR spectra, and, in the case of compounds 2-4, also by X-ray analysis. All of the isolated compounds were tested for their antibacterial activity against Gram-positive and Gram-negative bacteria, and multidrug-resistant isolates from the environment, as well as for their anti-quorum sensing based on the pigment production of Chromobacterium violaceum ATCC 31523. None of the compounds exhibited either antibacterial (MIC > 256 µg/mL) or anti-quorum sensing activities. The compounds were also inactive in the antifungal (MIC > 512 µg/mL) and cancer cell line (GI50 > 150 µM) assays.

An Endophytic Fungus, Talaromyces radicus, Isolated from Catharanthus roseus, Produces Vincristine and Vinblastine, Which Induce Apoptotic Cell Death

Endophytic fungi isolated from Catharanthus roseus were screened for the production of vincristine and vinblastine. Twenty-two endophytic fungi isolated from various tissues of C. roseus were characterized taxonomically by sequence analysis of the internal transcribed spacer (ITS) region of rDNA and grouped into 10 genera: Alternaria, Aspergillus, Chaetomium, Colletotrichum, Dothideomycetes, Eutypella, Eutypa, Flavodon, Fusarium and Talaromyces. The antiproliferative activity of these fungi was assayed in HeLa cells using the MTT assay. The fungal isolates Eutypella sp—CrP14, obtained from stem tissues, and Talaromyces radicus—CrP20, obtained from leaf tissues, showed the strongest antiproliferative activity, with IC₅₀ values of 13.5 μg/ml and 20 μg/ml, respectively. All 22 endophytic fungi were screened for the presence of the gene encoding tryptophan decarboxylase (TDC), the key enzyme in the terpenoid indole alkaloid biosynthetic pathway, though this gene could only be amplified from T. radicus—CrP20 (NCBI GenBank accession number KC920846). The production of vincristine and vinblastine by T. radicus—CrP20 was confirmed and optimized in nine different liquid media. Good yields of vincristine (670 μg/l) in modified M2 medium and of vinblastine (70 μg/l) in potato dextrose broth medium were obtained. The cytotoxic activity of partially purified fungal vincristine was evaluated in different human cancer cell lines, with HeLa cells showing maximum susceptibility. The apoptosis-inducing activity of vincristine derived from this fungus was established through cell cycle analysis, loss of mitochondrial membrane potential and DNA fragmentation patterns.

Talaromycolides A-C, Novel Phenyl-Substituted Phthalides Isolated from the Green Chinese Onion-Derived Fungus Talaromyces pinophilus AF-02

The green Chinese onion (Allium fistulosum L.), which is widely cultivated and has been naturalized in many places, is an important spice and vegetable in East and Southeast Asia. It is used to treat the common cold in China. In the ongoing search for antibacterial activity in fungi derived from natural, pungently scented vegetables, the secondary metabolites of Talaromyces pinophilus AF-02, which was isolated from the stem of the green Chinese onion, were investigated. The genus Talaromyces (Trichocomaceae) is an important fungal genus because of its ubiquity and the role of many of its species in food and agriculture production. Three new phthalide derivatives, talaromycolides A-C, 1-3; a new long-chain dicarboxylic acid, 11; and 12 known compounds were isolated from methanolic extracts of this fungus. Their structures were determined via extensive NMR, HR-ESI-MS, and CD spectroscopic analyses. Compounds 1-3 are rare phthalide derivatives with a novel linkage position between the phenyl and phthalide moieties. The biological properties of 1-16 were evaluated using six different bacteria, and 1-3, 5, and 11 exhibited significant antibacterial activity in response to some of the tested strains.

Unexpected talaroenamine derivatives and an undescribed polyester from the fungus Talaromyces stipitatus ATCC10500

Chemical investigation of the fungus Talaromyces stipitatus ATCC 10500, whose genome has been sequenced, led to the isolation of four undescribed talaroenamines B-E along with the known talaroenamine A. Their structures were elucidated on the basis of spectroscopic studies including mass spectrometry, extensive 2D NMR and electronic circular dichroism (ECD). Interestingly, talaroenamine A had previously been isolated from the strain of T. stipitatus Δtrop C, a strain knocked out for the gene encoding a non-heme Fe(II)-dependent dioxygenase catalyzing the oxidative ring expansion leading to the tropolone, but never from a wild-type strain. All talaroenamines were evaluated for their antiplasmodial activity and Talaroenamine D exhibited the best inhibition against the chloroquine-resistant Plasmodium falciparum (FcB1 strain) without noticeable toxicity on HeLa and preadipose cell lines. In the course of the chemical investigation of T. stipitatus, an undescribed polyester was also isolated and its absolute configuration was determined by hydrolysis and transesterification followed by gas chromatography on chiral column.

Dichlorinated and Brominated Rugulovasines, Ergot Alkaloids Produced by Talaromyces wortmannii

UHPLC-DAD-HRMS based dereplication guided the detection of new halogenated alkaloids co-produced by Talaromyces wortmannii. From the fungal growth in large scale, the epimers 2,8-dichlororugulovasines A and B were purified and further identified by means of a HPLC-SPE/NMR hyphenated system. Brominated rugulovasines were also detected when the microbial incubation medium was supplemented with bromine sources. Studies from 1D/2D NMR and HRMS spectroscopy data allowed the structural elucidation of the dichlorinated compounds, while tandem MS/HRMS data analysis supported the rationalization of brominated congeners. Preliminary genetic studies revealed evidence that FADH₂ dependent halogenase can be involved in the biosynthesis of the produced halocompounds.

[Two new polyesters from wetland soil-derived fungus Talaromyces flavus]

Two new polyesters, talapolyesters G-H (1-2) were isolated from the wetland soil-derived fungus Talaromyces flavus BYD07-13, and their structures were determined by NMR and MS spectroscopic data. The absolute configurations of the residues were determined by alkaline hydrolysis. The cytotoxicity against five tumor cell lines (HL-60, SMMC-7721, A-549, MCF-7 and SW480) of 1-2 was examined.

Drimane Sesquiterpene-Conjugated Amino Acids from a Marine Isolate of the Fungus Talaromyces minioluteus (Penicillium Minioluteum)

Four new sesquiterpene lactones (3, 4, 6 and 7) and three known compounds, purpuride (1), berkedrimane B (2) and purpuride B (5), were isolated from the marine fungus, Talaromyces minioluteus (Penicillium minioluteum). New compounds were drimane sesquiterpenes conjugated with N-acetyl-l-valine, and their structures were elucidated by analysis of spectroscopic data, as well as by single crystal X-ray analysis. The isolated compounds could not inhibit the apoptosis-regulating enzyme, caspase-3, while three of the compounds (2, 3 and 7) exhibited weak cytotoxic activity.