Secondary metabolites from the fungus Cladosporium xylophilum.

A new cladosporol derivative xylophilum A (1), together with 10 known compounds (2-11), were isolated from the rice fermentation of the fungus Cladosporium xylophilum. Their structures were established by extensive spectroscopic methods and comparison of their NMR data with literatures. The antimicrobial activity of compound 1 against 11 kinds of pathogenic microbial was evaluated, but no significant activity was found (MIC >100 µg/ml).

A new chamigrane sesquiterpene from the rice fermentation of Antrodiella albocinnamomea.

A new chamigrane sesquiterpene, albocimea A (1), and one known compound, 6-hydroxy-8-methoxy-3S,5-dimethylisochroman (2), were isolated from the rice fermentation of the fungus Antrodiella albocinnamomea. The structure of new compound was elucidated by extensive spectroscopic analyses and electronic circular dichroism (ECD) calculations. Both compounds were evaluated for their cytotoxicity against five human cancer cell lines, but no significant cytotoxicity was found (IC50 values > 40 µM).

A new chamigrane sesquiterpene from the basidiomycete Antrodiella albocinnamomea.

One new chamigrane sesquiterpene, antroalbol A (1), was isolated from the cultures of the higher fungus Antrodiella albocinnamomea. Its structure was established by means of spectroscopic methods, and the absolute configuration of 1 was confirmed by single crystal x-ray diffraction analysis. The compound was evaluated for its cytotoxicity against five human cancer cell lines, but no significant cytotoxicity was found.

Production of Minor Ginsenosides from Panax notoginseng Flowers by Cladosporium xylophilum.

Panax notoginseng flowers have the highest content of saponins compared to the other parts of Panax notoginseng, but minor ginsenosides have higher pharmacological activity than the main natural ginsenosides. Therefore, this study focused on the transformation of the main ginsenosides in Panax notoginseng flowers to minor ginsenosides using the fungus of Cladosporium xylophilum isolated from soil. The main ginsenosides Rb1, Rb2, Rb3, and Rc and the notoginsenoside Fa in Panax notoginseng flowers were transformed into the ginsenosides F2 and Rd2, the notoginsenosides Fd and Fe, and the ginsenoside R7; the conversion rates were 100, 100, 100, 88.5, and 100%, respectively. The transformation products were studied by TLC, HPLC, and MS analyses, and the biotransformation pathways of the major ginsenosides were proposed. In addition, the purified enzyme of the fungus was prepared with the molecular weight of 66.4 kDa. The transformation of the monomer ginsenosides by the crude enzyme is consistent with that by the fungus. Additionally, three saponins were isolated from the transformation products and identified as the ginsenoside Rd2 and the notoginsenosides Fe and Fd by NMR and MS analyses. This study provided a unique and powerful microbial strain for efficiently transformating major ginsenosides in P. notoginseng flowers to minor ginsenosides, which will help raise the functional and economic value of the P. notoginseng flower.

Four New Sesquiterpenoids from the Rice Fermentation of Antrodiella albocinnamomea.

Albocimea B-E (1-4), four new sesquiterpenoids, and four known compounds, steperoxide A (5), dankasterone (6), 1H-indole-3-carboxylic acid (7), and (+)-formylanserinone B (8), were isolated from the rice fermentation of the fungus Antrodiella albocinnamomea. The structures of new compounds were elucidated by comprehensive spectroscopic techniques, the planar structures of new compounds were determined by comprehensive spectroscopic techniques, and their absolute configurations were confirmed via gauge-independent atomic orbital calculations (GIAO), calculation of the electronic circular dichroism (ECD), and optical rotation (OR). These were determined by spectroscopic data analysis.

Highly Regioselective Biotransformation of Protopanaxadiol-type and Protopanaxatriol-type Ginsenosides in the Underground Parts of Panax notoginseng to 18 Minor Ginsenosides by Talaromyces flavus.

The transformation of major ginsenosides to minor ginsenosides by microorganisms was considered to be an environmentally friendly method. Compared with GRAS (generally recognized as safe) strains, non-food-grade microorganisms could transform polar ginsenosides to various minor ginsenosides. In this study, Talaromyces flavus screened from the P. notoginseng rhizosphere was capable of transforming PPD-type and PPT-type ginsenosides in the underground parts of P. notoginseng to 18 minor ginsenosides. The transformation reactions invovled deglycosylation, epimerization, and dehydration. To the best of our knowledge, this transformation characteristic of T. flavus was first reported in fungi. Its crude enzyme can efficiently hydrolyze the outer glucose linked to C-20 and C-3 in major ginsenosides Rb1, Rb2, Rb3, Rc, Rd, and 20(S)-Rg3 within 48 h. The transformation of major ginsenosides to minor ginsenosides by T. flavus will help raise the functional and economic value of P. notoginseng.