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Biotransformation of ursonic acid (1) by two fungal strains Aspergillus ochraceus CGMCC 3.5324 and Aspergillus oryzae CGMCC 3.407 yielded thirteen new compounds (4, 5, 7–10, and 13–19), along with five recognized ones. The structural details of new compounds were determined through spectroscopic examination (NMR, IR, and HR-MS) and X-ray crystallography. Various modifications, including hydroxylation, epoxidation, lactonization, oxygen introduction, and transmethylation, were identified on the ursane core. Additionally, the anti-neuroinflammatory efficacy of these derivatives was assessed on BV-2 cells affected by lipopolysaccharides. It was observed that certain methoxylated and epoxylated derivatives (10, 16, and 19) showcased enhanced suppressive capabilities, boasting IC50 values of 8.2, 6.9, and 5.3 μM. Such ursonic acid derivatives might emerge as potential primary molecules in addressing neurodegenerative diseases.

Resveratrol, a polyphenol compound with strong biological activity, has been widely used in medicine, health products and cosmetic industries. It is also the main active component of Polygonum cuspidatum, a well-known traditional Chinese medicine. We developed a simple and effective method for the preparation of resveratrol from P. cuspidatum. The whole preparative process consisted of reflux extraction, filtering, hydrolyzing, liquidâliquid extraction and eluting. Filtering is to remove non polar or less polar compounds and debris fragments from the extract. Hydrolyzing is to transform polydatin to resveratrol to improve the yield of resveratrol. Eluting is to remove impurities including strong acidic and water-soluble compounds. By acid hydrolysis of glycoside (polydatin), the yield of resveratrol increased about 4-fold. The extraction recovery in different stages was high, and the content of resveratrol in the final product was over 73.8%. Compared with other methods reported, this technology is eco-friendly, easier to perform, and also has a lower cost. Keywords: Polygonum cuspidatum, Resveratrol, Solvent extraction, Purification

Preparative-scale fermentation of ginsenoside Rb1 ( 1) with Acremonium strictum AS 3.2058 gave three new compounds, 12β-hydroxydammar-3-one-20 ( S)- O-β- d-glucopyranoside ( 7), 12β, 25-dihydroxydammar-( E)-20(22)-ene-3- O-β- d-glucopyranosyl-(1→2)-β- d-glucopyranoside ( 8), and 12β, 20 ( R), 25-trihydroxydammar-3- O-β- d-glucopyranosyl-(1→2)-β- d-glucopyranoside ( 9), along with five known compounds, ginsenoside Rd ( 2), gypenoside XVII ( 3), ginsenoside Rg3 ( 4), ginsenoside F2 ( 5), and compound K ( 6). The structural elucidation of these metabolites was based primarily on one- and two-dimensional nuclear magnetic resonance and high-resolution electron spray ionization mass spectra analyses. Among these compounds, 2– 6 are also the metabolites of ginsenoside Rb1 in mammals. This result demonstrated that microbial culture parallels mammalian metabolism; therefore, A. strictum might be a useful tool for generating mammalian metabolites of related analogs of ginsenosides for complete structural identification and for further use in pharmaceutical research in this series of compounds. In addition, the biotransformation kinetics was also investigated. [ABSTRACT FROM AUTHOR]

Four new lanostane triterpenoids, namely (3β)-3-hydroxy-24-methylenelanost-8-ene-7,11-dione (1), (3β)-3-hydroxylanosta-8,24-diene-7,11-dione (2), (3β,7α)-3,7-dihydroxylanosta-8,24-dien-11-one (3), and (3β,11β)-3,11-dihydroxylanosta-8,24-dien-7-one (4) were isolated from Euphorbia humifusa, together with 2 known compounds. The structures of these new compounds were elucidated on the basis of extensive spectroscopic analysis and comparison with the related known compounds. [ABSTRACT FROM AUTHOR]

The four new phenylpropanoid-substituted catechins 1, 3, and 4 and 3-epicatechin (2), together with seven analogues, were isolated from the AcOEt extract of Smilax china L. (catechin=(2R,3S)-2-(3,4-dihydroxyphenyl)-3,4-dihydro-2H-2-benzopyran-3,5,7-triol). Their structures were determined by means of spectroscopic analyses, including HR-MS, IR, 1H- and 13C-NMR, and 2D experiments (COSY, HSQC, and HMBC), and comparison with known related compounds. [ABSTRACT FROM AUTHOR]