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One new 2-oxaspiro[4.5]decane, roussoellide, and one new α- pyrenocine, 2 ' ,3 ' -dihydropyrenocine A, together with nine known compounds including known arthropsolide A, and pyrenocines A and E, were obtained from the culture broth of the endophytic fungus Roussoella sp. Their structures were determined using spectroscopic data. The absolute configuration of known arthropsolide A was assigned on the basis of X-ray diffraction data using Cu K α radiation. Known pyrenocine A displayed weak cytotoxic activity against breast cancer (MCF-7) cells with an IC 50 value of 27.1   µ M and weak antifungal activity against Microsporum gypseum SH-MU-4 with an MIC value of 615.2   µ M.[Formula: see text].

Seven new polyketides including a phenol ( 1 ), two diphenyl ethers ( 2 and 3 ), two depsidones ( 4 and 5 ), and two phthalides ( 6 and 7 ) were isolated from the fungus Aspergillus unguis PSU-MF16 along with 27 known compounds. Their structures were determined by extensive spectroscopic analysis. The absolute configurations of 1 and 4 - 7 were established using comparative analyses of calculated and experimental ECD spectra. Among the new metabolites, 2 exhibited the best antimicrobial activity against Staphylococcus aureus , methicillin-resistant S. aureus , and Microsporum gypseum with equal MIC values of 16 μg/mL. In addition, known emeguisin A displayed potent antimicrobial activity against S. aureus , methicillin-resistant S. aureus , and Cryptococcus neoformans with equal MIC values of 0.5 μg/mL, compared with the standard drugs, vancomycin and amphotericin B. The structure-activity relationship study of the isolated compounds for antimicrobial activity is discussed.

Nine previously undescribed depsidones (simplicildones A-I) and one previously undescribed α-pyrone (simplicilopyrone) were isolated from the endophytic fungus Simplicillium sp. PSU-H41 along with 11 known compounds. Their structures were established by extensive spectroscopic analysis. Simplicildone A and known botryorhodine C displayed weak antibacterial against Staphylococcus aureus with equal MIC values of 32 μg/mL. Additionally, botryorhodine C was active against methicillin-resistant S. aureus with the same MIC value. Simplicildone C exhibited weak antifungal activity against Cryptococcus neoformans with an MIC value of 32 μg/mL. In addition, simplicildones A and C and botryorhodine C were noncytotoxic against noncancerous Vero cells., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

One new difuranylmethane derivative, flavodonfuran (1), together with tremulenolide A (2) was isolated from the mangrove-derived fungus Flavodon flavus PSU-MA201.The difuranylmethane derivative based on 1 is rare in natural products. Their structures were established by spectroscopic evidence. Compound 2 exhibited mild antibacterial and antifungal activities against Staphylococcus aureus ATCC25923 and Cryptococcus neoformans ATCC90113, respectively.

Five new metabolites, fusaranthraquinone (1), fusarnaphthoquinones A-C (2-4), and fusarone (5), were isolated from the sea fan-derived fungi Fusarium spp. PSU-F14 and PSU-F135 along with 18 known compounds. The structures were elucidated on the basis of spectroscopic evidence. Their antibacterial, antifungal, antimycobacterial, antimalarial, and cytotoxic activities were examined.

This study aimed to isolate fungi from leaves, petals, stalks and stamens of Nymphaea lotus and Nymphaea stellata and explore their bioactive potential with respect to antimicrobial activity and their cytotoxicity on human cell lines. The totals of 210 fungal isolates were obtained from 640 segments. The highest isolation rate was found in petal segments (0.44), while stamens yielded the lowest isolation rate (0.13). One hundred and ninety–five fungal extracts were evaluated for their efficiency against ten pathogenic microorganisms by colorimetric broth microdilution tests. Cell hexane extract from Eupenicillium levitum FNL036 (FNL036CH) gave the strongest antifungal activity against Cryptococcus neoformans and Talaromyces marneffei with minimum inhibitory concentration of 0.5 μg/mL and affected cell morphology of the test microorganisms. Moreover, this extract was non–cytotoxic to human embryonic kidney 293 (293T) and human keratinocytes (HaCAT) cell lines with 50% inhibitory concentration (IC 50 ) values above 100 μg/mL. This finding confirmed that fungi derived from these two Nymphaea species were a novel source of bioactive metabolites. [ABSTRACT FROM AUTHOR]

Abstract: Five new polyketides including two benzopyranones (1 and 2), one isochroman (3) and two anthraquinone-citrinin derivatives (4 and 5) were isolated from the sea fan-derived fungus Penicillium citrinum PSU-F51 together with thirteen known compounds. The structures were determined by spectroscopic methods. The anthraquinone-citrinin derivatives are rare natural products. Compound 4 displayed moderate antibacterial activity against both Staphylococcus aureus and methicillin-resistant S. aureus with equal MIC values of 16 μg/mL, while the known coniochaetone A displayed moderate antifungal activity against Candida albicans with MIC value of 16 μg/mL. [Copyright &y& Elsevier]