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Sea cucumber-derived fungi have attracted much attention due to their capacity to produce an incredible variety of secondary metabolites. Genome-wide information on Aspergillus micronesiensis H39 obtained using third-generation sequencing technology (PacBio-SMRT) showed that the strain contains nonribosomal peptide synthetase (NRPS)-like gene clusters, which aroused our interest in mining its secondary metabolites. 11 known compounds (1–11), including two γ-aromatic butenolides (γ-AB) and five cytochalasans, were isolated from A. micronesiensis H39. The structures of the compounds were determined by NMR and ESIMS, and comparison with those reported in the literature. From the perspective of biogenetic origins, the γ-butyrolactone core of compounds 1 and 2 was assembled by NRPS-like enzyme. All of the obtained compounds showed no inhibitory activity against drug-resistant bacteria and fungi, as well as compounds 1 and 2 had no anti-angiogenic activity against zebrafish. [ABSTRACT FROM AUTHOR]

A novel nitro-phenyl glucoside (1) was isolated from mangrove endophytic fungus (fungus B60), collected from the Shenzhen mangrove Acanthus ilicifolius linn. Four related nitro-phenyl compounds (2-5) were also obtained, which were isolated for the first time as natural products. Their structures were established on the basis of NMR spectroscopic, mass spectrometric data and some chemical transformations. In the preliminary bioassay, compound 1 had a slight inhibitory effect on α-glucosidase with an IC50 of 160.3 μM. [ABSTRACT FROM AUTHOR]

Zebrafish models were used to study the bioactivity of compound B 1 b , which showed that this cyclopeptide had good angiogenic and antiepileptic effects. 2, compound B 1 b pretreatment of PTZ-induced seizures in zebrafish can reduce excessive movement, speed of movement, and total distance of movement. The isolated compounds were identified through NMR data analysis and high-resolution mass spectrometry as cyclo(L-Pro-D-Tyr) ( B 1 b ), lumichrome ( B 2 b ), 4-hydroxyphenylacetic acid ( B 3 b ), 3-indolcarbaldehyde ( B 4 b ), indole-3-carboxylic acid ( B 5 b ), indole-2,3-dione ( B 6 b ), I p i -hydroxybenzaldehyde ( B 7 b ), and I N i -(phenylmethyl)carbamic acid ( B 8 b ). Fraction 8 (128.2 mg) was similarly purified by HPLC (H SB 2 sb O-MeOH, 50:50) to obtain three fractions (Fr. 8-1 (13.3 mg), Fraction 8-2 (compound B 3 b , 36.0 mg), and Fr. 8-3 (21.2 mg). [Extracted from the article]

Three new lupane-triterpenoids (1–3) along with six known compounds (4–9) were isolated from the ethanolic extract of whole plant of Potentilla discolor Bunge. The structures of Compounds 1–3 were established by extensive 1D and 2D NMR together with other spectrum analysis, indicating that their C-27 positions were highly oxygenated, which were rarely found in nature. Their in vitro anti-proliferative activities against HepG-2, MCF-7 and T-84 cell lines were evaluated by Cell Counting Kit-8 (CCK-8) assay, and the results showed different activities for three cell lines with IC50 values ranging from 17.84 to 40.64 μM. In addition, the results from Hoechst 33258 and AO/EB staining as well as annexinV-FITC assays exhibited Compound 1 caused a markedly increased HepG-2 cellular apoptosis in a dose-dependent manner. The further mechanisms of Compound 1-induced cellular apoptosis were confirmed that 1 induced the production of ROS and the alteration of pro- and anti-apoptotic proteins, which led to the dysfunction of mitochondria and activation of caspase-9 and caspase-3 and finally caused cellular apoptosis. These results would be useful in search for new potential antitumor agents and for developing semisynthetic lupane-triterpenoid derivatives with high antitumor activity. [ABSTRACT FROM AUTHOR]