Chemical constituents of the marine-derived fungus Acremonium sp. AN-13.

Two new compounds named 3(S)-hydroxy-1-(2,4,5-trihydroxy-3,6- dimethylphenyl)-hex-4E-en-1-one (1) and acremonilactone (2), together with nine known compounds (3-11), were isolated from the fermentation broth of Acremonium sp. associated with marine sediments collected from South China Sea. NMR and HRESIMS spectroscopic analysis elucidated the structure of two new compounds. Compound 2 had characteristic rotary gate shape skeleton with a six-membered lactone. Compounds 1 and 9 showed DPPH radical scavenging activity with inhibition rates of 96.50 and 85.95% at the concentration of 0.5 mg/ml, respectively. Moreover, compounds 4, 6 and 11 showed definite antibacterial activity against Staphylococcus aureus ATCC 6538.

Asperpenes D and E from the fungus Aspergillus sp. SCS-KFD66 isolated from a bivalve mollusk, Sanguinolaria chinensis.

Two new compounds named asperpenes D (1) and E (2) were isolated from the marine-derived fungus Aspergillus sp. SCS-KFD66. Their structures were determined on the basis of spectroscopic methods. Compound 2 represents the first natural product bearing a 2-substituted-5-oxo-4-phenyl-2,5-dihydrofuran-3-carboxylic acid skeleton. All the compounds were tested for enzyme inhibitory activity against AChE and α-glucosidase and DPPH radical scavenging activity, respectively. [Formula: see text].

[Study on chemical constituents from fruiting bodies of Ganoderma australe].

Chemical constituents were isolated from the fruiting bodies of Ganoderma australe by various column chromatographic techniques and HPLC method, and their chemical structures were identified through the combined analysis of physicochemical properties and spectral data. Meanwhile, their α-glucosidase inhibitory activity and anti-oxidative ability were evaluated. Seven compounds were isolated from G. australe and were identified as 6-methoxyl-cyclo-(Phe-Ile)(1), applanoxidic acid A methyl ester(2), ergosta-7,22 E-dien-3ß-ol(3), cinnamic acid(4), 5α,8α-epidioxy-(20S,22E,24R)-ergosta-6,22-diene-3ß-ol(5), 1-(3, 4-dihydroxyphenyl) ethanone(6), salicylic acid(7) and benzoic acid(8). Among the compounds, compound 1 was a new cyclic dipeptide. Compound 2 was a new lanosta natural product, and compounds 4, 6, 7 and 8 were obtained from G. australe for the first time. Moreover, compounds 4 and 8 exhibited α-glucosidase inhibitory activity with inhibition rates of 36.8% and 34.7%, and compounds 4, 7 and 8 had a certain activity in DPPH free radical scavenging activity with IC_(50) values of 0.168, 0.458 and 0.170 g·L~(-1), respectively. The DPPH radical scavenging rate of compound 1 was 41.1%.

Chemical Constituents of the Marine-Derived Fungus Aspergillus sp. SCS-KFD66.

Five new compounds named asperpenes A-C (1⁻3), 12,13-dedihydroversiol (4), and methyl 6-oxo-3,6-dihydro-2H-pyran-4-carboxylate (5), along with 10 known compounds (6⁻15), were isolated from the fermentation broth of Aspergillus sp. SCS-KFD66 associated with a bivalve mollusk, Sanguinolaria chinensis, collected from Haikou Bay, China. The structures of the compounds, including the absolute configurations of their stereogenic carbons, were unambiguously determined by spectroscopic data, single-crystal X-ray diffraction analysis, and electronic circular dichroism (ECD) spectral analysis, along with quantum ECD calculations. The growth inhibitory activity of the compounds against four pathogenic bacterial (Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 6538, Listeria monocytogenes ATCC 1911, and Bacillus subtilis ATCC 6633), their enzyme inhibitory activities against acetylcholinesterase and α-glucosidase, and their DPPH radical scavenging activity were evaluated.