Search

The chemical examination of the rice solid fermentation products of the deep-sea-derived fungus Aspergillus puniceus A2 resulted in the isolation of one new sesquiterpenoid malfilanol C ( 1 ), together with a rare analogue malfilanol B ( 2 ). The planar structure of 1 was resolved on the basis of the extensive analyses of the spectroscopic data (HRESIMS and NMR spectra), and its absolute configuration was assigned by quantum chemical calculation of the ECD data. Compound 1 , featuring a bicyclo[5.4.0]-undecane nucleus skeleton, was the third example of this subclass sesquiterpenoids found from nature. Additionally, the subclass sesquiterpenoids 1 and 2 were discovered from marine-derived-fungi for the first time. All the isolated metabolites were evaluated the antibacterial activities against Staphylococcus aureus ATCC 29213 and Escherichia coli ATCC 25922. Compound 1 exhibited weak antibacterial activity against S. aureus ATCC 29213.

Seventeen undescribed sesquiterpenoids including 14 phenolic bisabolanes, namely asperbisabolanes A-N (1-14), and 3 cuparenes (aspercuparenes A-C, 15-17), together with 10 known bisabolane analogues (18-27) were isolated from the EtOAc extract of fermented cultures of the deep sea sediment-derived fungus Aspergillus sydowii MCCC 3A00324. The new structures were established on the basis of extensive NMR and HRESIMS spectroscopic data analyses, while their absolute configurations were assigned by comparison of the experimental ECD spectra with those of the TDDFT-ECD calculated spectra or reported data in literature. Asperbisabolanes A (1) and B (2) are the first examples of bisabolane sesquiterpenoids featuring a 6/6/6 tricyclic nucleus. Compound 3 possessed a novel seco-bisabolane skeleton with a rare dioxolane ring moiety, while asperbisabolane K (11) represents the first case of bisabolanes bearing a rare methylsulfonyl group. All the isolated compounds (1-27) were evaluated their activities against NO secretion in LPS-activated BV-2 microglia cells. As a result, 6, 12, 16, and 25-27 exhibited the inhibition rate over 45% at a concentration of 10 µM. Moreover, 12 exerted the anti-inflammatory activity by inhibiting the NF-κB-activated pathway in dose-dependent manner., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Chemical study of the secondary metabolites of a deep-sea-derived fungus Aspergillus sydowii MCCC 3A00324 led to the isolation of eleven compounds ( 1 - 11 ), including one novel ( 1 ) and one new ( 2 ) osmane-related monoterpenoids and two undescribed polyketides ( 3 and 4 ). The structures of the metabolites were determined by comprehensive analyses of the NMR and HRESIMS spectra, in association with quantum chemical calculations of the 13 C NMR, ECD, and specific rotation data for the configurational assignment. Compound 1 possessed a novel monoterpenoid skeleton, biogenetically probably derived from the osmane-type monoperpenoid after the cyclopentane ring cleavage and oxidation reactions. Additionally, compound 3 was the first example of the α -pyrone derivatives bearing two phenyl units at C-3 and C-5, respectively. The anti-inflammatory activities of 1 - 11 were tested. As a result, compound 6 showed potent inhibitory nitric oxide production in lipopolysaccharide (LPS)-activated BV-2 microglia cells with an inhibition rate of 94.4% at the concentration of 10 µM. In addition, a plausible biosynthetic pathway for 1 and 2 was also proposed.

Chemical investigation of the deep-sea-derived fungus Aspergillus sydowii MCCC 3A00324 led to the isolation of one new acremolin type alkaloid (acremolin D, 1) and five known alkaloids (2‒6). The planar structure of 1 was established by the extensive analyses of the NMR and HRESIMS data, while its absolute configuration was assigned by the comparison of the experimental and calculated ECD data. Acremolin D (1) represented the second analogue of acremolin found in nature. All compounds were evaluated for their cytotoxic activities against six human cancer cell lines (A549, Hela-S3, MCF-7, HepG2, K562, and SF-268). As a result, compounds 1 and 2 exhibited a certain inhibitory effects against the proliferation of the A549, Hela-S3, HepG2, and K562 cell lines at the concentration of 20 µM. [ABSTRACT FROM AUTHOR]