Pyridine pigments from functional Monascus rice / 药学学报

The trace chemical components in functional Monascus rice were studied to explore the potential bioactive substances. MCI column, Sephadex LH-20 gel, and preparative liquid chromatography were used to purified the ethyl acetate extract from functional Monascus rice. Two novel pyridine Monascus pigments were isolated and identified, named monascopyridine G (1) and monascopyridine H (2), respectively based on extensive mass spectrometry (MS), infrared radiation (IR), and nuclear magnetic resonance (NMR) analysis. The molecular docking experiments between compounds 1 and 2 and peroxisome proliferators-activated receptor-gamma (PPARγ) showed that they exhibited obvious binding force with the receptor protein. Besides, the biosynthetic pathways of the two compounds were proposed, which provide a valuable reference for the selective production of these potential bioactive substances.

Gene mining and efficient biosynthesis of a fungal peptidyl alkaloid / 中草药·英文版

Objective: Peptidyl alkaloids, a series of important natural products can be assembled by fungal non-ribosomal peptide synthetases (NRPSs). However, many of the NRPSs associated gene clusters are silent under laboratory conditions, and the traditional chemical separation yields are low. In this study, we aim to discovery and efficiently prepare fungal peptidyl alkaloids assembled by fungal NRPSs. Methods: Bioinformatics analysis of gene cluster containing NRPSs from the genome of Penicillium thymicola, and heterologous expression of the putative gene cluster in Aspergillus nidulans were performed. Isolation, structural identification, and biological evaluation of the product from heterologous expression were carried out. Results: The putative tri-modular NRPS AncA was heterologous-expressed in A. nidulans to give anacine (1) with high yield, which showed moderate and selective cytotoxic activity against A549 cell line. Conclusion: Heterologous expression in A. nidulans is an efficient strategy for mining fungal peptidyl alkaloids.

Hetero-biosynthesis of the main bioactive components from medicinal fungus Shiraia bambusiccola / 药学学报

italic>Shiraia bambusiccola is an important medicinal fungus in China. Hypocrellins with perylenequinone skeleton are main bioactive components of Shiraia bambusiccola, which are widely used in food, medicine, pesticide and other fields as natural photosensitizers. For example, "hypocrellin ointment" has already been used clinically. As a rare and vulnerable species, wild Shiraia bambusiccola resources are very limited. Due to the complex structure and chanllenge in chemical total synthesis of hypocrellins, it is urgent to find an effective strategy to rationally utilize its medicinal value while protecting the wild resources. In this study, a candidate gene cluster hpc was identified in Shiraia sp. cfcc 84681 based on careful bioinformatic analysis. A heterologous expression system for hpc gene cluster was successfully constructed and a mutant strain with high yield of hypocrellins was obtained, which mainly produced hypocrellin A and isohypocrellin A. The main ingredients in the mutant strain are consistent with that in the wild Shiraia bambusiccola. These results provide a new strategy to solve the shortage of wild Shiraia bambusiccola resources.

Six new monacolin analogs from red yeast rice / 中国天然药物

Six novel monacolin analogs, monacolins V-V (1-6), together with seven known ones (7-13), were isolated from the ethyl acetate extract of red yeast rice. Their structures and absolute configurations were determined by spectroscopic methods, especially 2D NMR (H-HCOSY, HSQC, HMBC, and NOESY/ROESY) and CD spectroscopic analyses as well as chemical derivation. Monacolins V (2) and V (3) represent the first examples of monacolins with 3-hydroxybutyrate substitute. The anti-inflammatory inhibitory activities against the lipopolysaccharide (LPS) induced NO production in BV-2 cells as well as antioxidant activities against rat liver microsomal lipid peroxidation were evaluated.

Trace phenolic compounds from Red Yeast Rice / 中国中药杂志

Trace chemical constituents from the ethyl acetate extract of Red Yeast Rice were investigated. Four phenolic compounds were isolated by various column chromatographies, and their structures were identified on the basis of spectroscopic analysis including UV, MS, IR and NMR. The four compounds were identified as 2-methyl-5-(2'R-methyl-4'-hydroxy-butyl)-cinnamic acid(1), 5-(2'-hydroxy-6'-methyl phenyl)-3-methylfuran-2-carboxylic acid(2), daidzein(3), and genistein(4). Compound 1 was new and 2 was firstly discovered from the genus Monascus, while 3-4 were obtained from Red Yeast Rice for the first time.

Studies on chemical constituents of Cynanchum forrestii / 中国中药杂志

<p><b>OBJECTIVE</b>To study the chemical constituents of Cynanchum forrestii.</p><p><b>METHOD</b>Chromatographic techniques were applied to isolated chemical constituents. The structures were identified on the basis of physico-chemical constants and spectroscopic data.</p><p><b>RESULT</b>Eight compounds were isolated from the 95% ethanol extract of the roots of C. forrestii and elucidated as ( + ) -5'-methoxyisolariciresinol 3a-O-beta-D-glucopyranoside (1), hexahydroxycholest-7-en-6-one (2), tylophorinidine (3), sucrose (4), palmitic acid (5), beta-sitosterol (6), daucosterol (7), nonanedioic acid (8).</p><p><b>CONCLUSION</b>Compounds 1-3 from this genus, and compounds 4-8 from the plant were obtained for the first time.</p>

Studies on chemical constituents from roots of Craibiodendron henryi / 中国中药杂志

<p><b>OBJECTIVE</b>To study the chemical constituents from the roots of Craibiodendron henryi.</p><p><b>METHOD</b>Various chromatographic techniques were used to isolate and purify the constituents. The structures were elucidated by chemical evidence and spectral methods.</p><p><b>RESULT</b>Twelve compounds were isolated from the ethyl acetate soluble fraction of the 95% ethanolic extract and their struc- tures were elucidated as quercetin (1), quercetin-3-O-rhamnicoside (2), quercetin-3-O-arabinofuranoside (3), (-)-epicatechin (4), proanthocyanidin A-2 (5), procyanidin B-2 (6), (-)-isolariciresinol-2a-O-beta-D-xylopyranoside (7), lyoniside (8), sitoster-yl-3beta-glucoside-6'-O-palmitate (9), beta-sitosterol (10), daucosterol (11) and octacosanoic acid (12).</p><p><b>CONCLUSION</b>Compounds 1-12 were isolated from this plant for the first time.</p>