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In our continuous work on the isolation of endophytes, the endophytic fungal strain YIMF00209 was obtained from the roots of Gmelina arborea , which is an ethnic medicinal plant mainly distributed in Southeast Asia. The fermentation extracts of the strain exhibited significant antimicrobial activities against Staphylococcus aureus , Fusarium solani , and Escherichia coli. Based on morphological characteristics and phylogenetic analysis, it was identified as Talaromyces muroii. Four new polyketides, talaromurolides A-D (1 – 4), along with 26 known compounds (5 – 30), were isolated from the culture broth of the strain in two different media. Their structures were identified based on HRESIMS, NMR, and CD spectral data. Among them, compounds 2 , 4 – 6 , 19 , 22 , 24 , 27 , 28 , and 30 were isolated from the fermentation broth in CYM medium; compounds 1 , 3 , 7 – 18 , 20 , 21 , 23 , 25 , 26 , and 29 were obtained from the fermentation broth in PDB medium; and compounds 2 , 5 , and 30 were existed in both two media. Compounds 6 – 9 , 12 , 16 , 20 , 21 , 23 , 25 , and 29 were obtained from the genus Talaromyces for the first time. The antimicrobial activities of several compounds were assayed against six pathogens. Compound 1 exhibited inhibitory activities against S. aureus , E. coli , Candida albicans , Salmonella typhimurium , and Botrytis cinerea with MIC value of 64 μg/mL. Compound 25 exhibited antibacterial activity against E. coli with MIC value of 32 μg/mL. [Display omitted] [ABSTRACT FROM AUTHOR]

Aspercitrininone A (1), a novel polyketide featuring an unprecedented tetracyclic 6/6/6/5 spiral skeleton, was obtained from the rice fermentation cultures of the fungus Aspergillus cristatus together with five known compounds (2 – 6). Their structures were determined by HRESIMS data, 1D and 2D NMR spectroscopic analysis, and electronic circular dichroism (ECD) calculations. Aspercitrininone A was revealed as a new type of C/D cycle spiral structure and an unusual addition product of o-quinoid form citrinin with 2-methylterrefuranone. Compounds 1 , 4 , and 5 exhibited potent antibacterial activities with minimal inhibitory concentration (MIC) values from 13.2 to 67.3 μg/mL against four strains of human pathogenic bacteria in vitro. [Display omitted] • A novel polyketide aspercitrininone A was isolated from rice cultures of Aspergillus cristatus. • Aspercitrininone A possessed an unprecedented tetracyclic 6/6/6/5 spiral skeleton. • It could be formed by o-quinoid form citrinin with 2-methylterrefuranone through Michael addition reaction. • Aspercitrininone A exhibited antibacterial activities. [ABSTRACT FROM AUTHOR]

Two novel fungal polyketides, phometides A (1) and B (2), together with four known compounds (3–6), were isolated from the endophytic fungus Phoma sp. YUD17001 obtained from Gastrodia elata Blume. The structures were elucidated based on spectroscopic analyses, X-ray crystal diffraction, and time-dependent density functional theory/electronic circular dichroism (TDDFT/ECD) calculations. Structurally, phometide A (1) represented the first example of C 12 polyketide characterized by an unusual tetrahydrobenzofuran-3(2 H)-one core with an α , β -unsaturated ketone functionality, while phometide B (2) was an unprecedented molecule containing a 2-pentylcycloheptan-1-one scaffold. In an antimicrobial activity assay, phometide A (1) exhibited significant inhibitory activity against Staphylococcus aureus with MIC value of 4 μg/mL. Phometide B (2) showed moderate antifungal activity against Candida albicans with an MIC value of 16 μg/mL. Furthermore, compounds 1 and 2 were evaluated for their acetylcholinesterase inhibitory and cytotoxic activities. [Display omitted] • Two novel fungal polyketides were identified from the endophytic fungus Phoma sp. YUD17001. • Phometide A possess an unusual tetrahydrobenzofuran-3(2 H)-one functionality. • Phometide B is a novel polyketone containing a 2-pentylcycloheptan-1-one scaffold. • Phometides A and B demonstrated antimicrobial activity against S. aureus and C. albicans , respectively. [ABSTRACT FROM AUTHOR]

Abstract A total of 180 fungal isolates, belonging to 20 genera and 47 species, were obtained from the roots, stems and leaves of Panax notoginseng. One isolate, the endophytic fungus Penicillium janthinellum SYPF 7899, displayed the strongest antibacterial activity and was studied for its production of secondary metabolites. In total, three new compounds, including rotational isomers 1a, 1b and 2 were isolated from the solid cultures of P. janthinellum , as well as eight known compounds (3 − 10). These structures were determined on the basis of 1D, 2D NMR and electronic circular dichroism (ECD) spectroscopic analyses as well as theoretical calculations. Compound 1 exhibited significant inhibitory activities against Bacillus subtilis and Staphylococcus aureus with MIC values of 15 and 18 μg/ml, respectively. The other compounds showed moderate or weak activities. In addition, morphological observation showed the rod-shaped cells of B. subtilis growing into long filaments, which reached 1.5- to 2-fold of the length of the original cells after treatment with compound 1. The coccoid cells of S. aureus exhibited a similar response and swelled to a 2-fold volume after treatment with compound 1. In silico molecular docking was explored to study the binding interactions between the compounds and the active sites of filamentous temperature-sensitive protein Z (FtsZ) from B. subtilis and S. aureus. Compound 1a, 1b and 2 showed high binding energies, strong H-bond interactions and hydrophobic interactions with FtsZ. Based on the antimicrobial activities, cellular phenotype observation and docking studies, compound 1 is considered to be a promising antimicrobial inhibitor of FtsZ. Graphical Abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Four new phenylisotertronic acids ( 1a/1b , 2a , and 3a ) were isolated from a TCM endophytic fungal strain Phyllosticta sp. J13-2-12Y obtained from the leaves of Acorus tatarinowii , along with two known ones ( 2b and 3b ). Compounds 1 − 3 all existed as mixtures of enantiomers, and their corresponding optically pure enantiomers were successfully isolated by chiral HPLC. The structures of isolated compounds were determined by comprehensive spectroscopic analyses and X-ray diffraction. Their absolute configurations were determined by ECD experiments and quantum chemical calculations. In addition, the antimicrobial activities and the cytotoxicities of these three pairs of optically pure enantiomers ( 1a/1b , 2a / 2b , and 3a/3b ) had been evaluated. [ABSTRACT FROM AUTHOR]

Two altenuene derivatives ( 1 – 2 ) and one isocoumarin ( 3 ), together with six known compounds ( 4 – 9 ) were isolated from solid cultures of an endophytic fungus Alternaria alternata , obtained from the fresh branches of Camellia sinensis . Chiral analysis revealed the racemic nature of 1 and 2 , which were subsequently resolved into two pairs of enantiomers [(+)- 1 and (−)- 1 , (+)- 2 and (−)- 2 ]. Structures of all the isolates were identified through spectroscopic data. Absolute configurations of the two pairs of enantiomers were determined by electronic circular dichroism (ECD) calculation and the chiral center of C-10 in 3 was deduced via [Rh 2 (OCOCF 3 ) 4 ]-induced CD experiment. All the isolates were evaluated for their antimicrobial abilities against the pathogenic bacteria and fungi as well as cytotoxic activities against two human tumor cell lines. Compound 5 was the most active against Bacillus subtilis with MIC 80 of 8.6 μ g/ml, and compounds 1 – 3 , 6 – 7 and 9 exhibited moderate to weak inhibition towards the test pathogenic microorganism. Compound 4 showed mild cytotoxic activity against human osteosarcoma cells U2OS with IC 50 of 28.3 μ M. [ABSTRACT FROM AUTHOR]

Three new polyketides named penialidins A–C ( 1 – 3 ), along with one known compound, citromycetin ( 4 ), were isolated from an endophytic fungus, Penicillium sp., harbored in the leaves of the Cameroonian medicinal plant Garcinia nobilis . Their structures were elucidated by means of spectroscopic and spectrometric methods (NMR and HRMS n ). The antibacterial efficacies of the new compounds ( 1 – 3 ) were tested against the clinically-important risk group 2 (RG2) bacterial strains of Staphylococcus aureus and Escherichia coli . The ecologically imposing strains of E. coli (RG1), Bacillus subtilis and Acinetobacter sp. BD4 were also included in the assay. Compound 3 exhibited pronounced activity against the clinically-relevant S. aureus as well as against B. subtilis comparable to that of the reference standard (streptomycin). Compound 2 was also highly-active against S. aureus . By comparing the structures of the three new compounds ( 1 – 3 ), it was revealed that altering the substitutions at C-10 and C-2 can significantly increase the antibacterial activity of 1 . [ABSTRACT FROM AUTHOR]

Two novel sulfur-containing dibenzofurans, sorbusins A (1) and B (2), two unprecedented biphenyl glycosides, 2′-hydroxyaucuparin 2′- O - ɑ -L-rhamnoside (3) and noraucuparin 5- O - ɑ -L-rhamnoside (4), and four known analogues (5 – 8), were isolated from Sorbus pohuashanensis suspension cell induced by yeast extract. Their structures were elucidated based on spectroscopic analyses and quantum calculation of 13C NMR data. Structurally, compound 1 possessed a rare naturally occurring benzothiazole moiety and represents the first example of thiazole fused dibenzofuran. A plausible biosynthetic pathway for the sulfur-containing dibenzofurans is proposed. These dibenzofuran and biphenyl phytoalexins were evaluated for their antimicrobial activities against pathogenic fungi and drug-resistant bacteria. Compound 7 exhibited significant antibacterial activity against methicinllin-resistant Staphylococcus aureus with an MIC value of 3.13 μg/mL. [Display omitted] • Sulfur-containing dibenzofurans were isolated from Sorbus pohuashanensis suspension cell. • The quantum calculation of 13C NMR data was applied for structure elucidation. • This is the first example of naturally occurring thiazole fused dibenzofuran. • A plausible biosynthetic pathway for the sulfur-containing dibenzofurans is proposed. • The dibenzofuran and biphenyl phytoalexins were evaluated for their antifungal and antibacterial activities. [ABSTRACT FROM AUTHOR]

Six new compounds [ascherlactones A (1) and B (2), ascherchromanone A (3), phenethyl 4′- O -methylglucoside (8), 4′- O -methylpleoside (10), and 4′- O -methyltorachrysone 8- O -glucoside (11)] and one naturally new compound [4′- O -methyl-β- d -benzylglucoside (9)] together with fourteen known compounds, including paecilodepsipeptides A (5), B (7), and D (4), conoideocrellide A (6), eugenin (12), 5-hydroxy-2,3-dimethyl-7-methoxychromone (13), (S)-1-phenyl-1,2-ethanediol (14), (2 S)- l -3-phenyllactic acid (15), papuline [or (2 S)- l -3-phenyllactic acid methyl ester, 16 , 2′- epi terpendole A (17), terpendoles C (18) and D (19), cholic acid, and zeorin were isolated from the entomopathogenic fungus Aschersonia confluens BCC53152. Their chemical structures were elucidated on the basis of NMR spectroscopic and mass spectrometric analyses. The absolute configurations were determined by using the evidence from NOESY correlations, chemical means, optical rotation values together with comparison of ECD spectroscopic data with the calculated ECD spectra. The plausible biosynthetic pathway of compounds 1 – 3 was also proposed. Moreover, antimicrobial activity such as antimalarial, antitubercular, antifungal, and antibacterial activities and cytotoxicity against cancerous (MCF-7, KB, and NCI-H187) and non-cancerous (Vero) cells of the isolated compounds were evaluated. Unlabelled Image [ABSTRACT FROM AUTHOR]

A new alkaloid, named (±)-preisomide (1), together with five known polyketides (2 – 6), were isolated from an endophytic fungus Preussia isomera in Panax notoginseng by using one strain-many compounds (OSMAC) strategy. Their structures were identified by extensive spectroscopic experiments and comparison with literature data. Structurally, compound 1 possessed a rare naturally occurring tetrahydro-2 H -1,2-oxazin ring. Compound 6 displayed significant antibacterial activity against multidrug-resistant Enterococcus faecium , methicinllin-resistant Staphylococcus aureus and multidrug-resistant Enterococcus faecalis with an MIC value of 25 μg/mL, as well as moderate antifungal activity against Gibberella saubinetii with an MIC value of 50 μg/mL. Unlabelled Image [ABSTRACT FROM AUTHOR]

Fourteen new compounds including thirteen drimane – phthalide derivatives (fendlerals A – C, fendlerins A – D, fendlerols A – B, fendleric acids A – C, fendlerinine G) and one terphenyl derivative (fendleryl E) along with eight known compounds, fendlerinine A, rickenyls C – D, fendleryls C – D, atromentin, tetramethyl atromentin, and (±)-microsphaerophthalide F, were isolated from the wood fungus Hypoxylon fendleri BCC32408. Compared with the prior work, the results indicated the agitation effect on the production of bioactive drimane – phthalides. The chemical structures were determined based upon spectroscopic analyses and the absolute configurations were verified by comparison of the ECD spectral data with the calculated ECD spectra of the related compounds. Compounds 1–3 exhibited antimicrobial activity against Plasmodium falciparum (IC 50 4.15–4.39 μM), Colletotrichum capsici (MIC 6.25–12.5 μg/mL), and Bacillus cereus (MIC 1.56–3.13 μg/mL). All tested compounds displayed broad cytotoxicity against cancerous (MCF-7, KB, and NCI-H187) and non-cancerous (Vero) cells. Unlabelled Image [ABSTRACT FROM AUTHOR]

Two new sesquiterpenoids, leptosphins A (1) and B (2), and a new cyclopiane diterpene, leptosphin C (3), along with four known diterpenes (4–7) were isolated from the solid fermentation cultures of an endophytic fungus Leptosphaeria sp. XL026 isolated from the leaves of Panax notoginseng. Their structures were elucidated by extensive spectroscopic methods and single-crystal X-ray diffraction (data). Compound 1 represents the first sulfur-containing eremophilane sesquiterpene. Compounds 5 and 7 displayed medium antifungal activity against Rhizoctonia cerealis , as well as 6 against Verticillium dahliae Kleb with an MIC value of 12.5 μg/mL. Furthermore, compounds 2 , 5, 6 and 7 showed medium antibacterial activity against Bacillus cereus with MIC values of 12.5–6.25 μg/mL, as well as 6 also against Pseudomonas aeruginosa with an MIC value of 12.5 μg/mL. Unlabelled Image [ABSTRACT FROM AUTHOR]