To optimize the extraction technology of the total saponins in Dipsaci Radix, the extraction efficiency of total saponins was investigated with respecting to three variables including time, ethanol concentration and liquid-to-solid ratio. On the basis of a series of one-factor-at-a-time experiments, a polynomial regression model equation was fitted by the combined use of central composite experimental design and regression analysis. By analyzing the regression model using response surface analysis, the optimum extraction conditions of total saponins from Dipsaci Radix were identified as follows: 7 times of 55% alcohol, refluxing 3 times, 2.8 hours every time, and the extraction efficiency of total saponins was up to 0.201 1 g·g-1 and the asperosaponin Ⅵ was up to 0.015 4 g·g-1 under the optimized conditions. Confirmatory experiment indicated the good prediction ability of the established model and provided the basis for further development and utilization of Dipsaci Radix.

OBJECTIVETo investigate the chemical constituents of an endophytic fungus, F-31, from Annona muricata and search antitumor natural products.

METHODAfter scaling up, the fermentation broth and mycelia were extracted by macroporous resin and chromatographied by silica gel column, Sephadex LH-20 gel column and semi-preparative HPLC. The structures of compounds were determined by the means of extensive spectroscopic data The activity of the compounds were evaluated through MTT assay.

RESULTSix compounds were isolated from the fermentation broth and mycelia of this fungus, their structures were identified as 5-(3-hydroxybutyl)furan-2(5H)-one(1), chloranthalactone E(2), 5, 7-dimethyl-6-hydroxycoumarin(3), 1, 2, 4-triazole-(1'R, 2'R, 3'R, 4'R)-nucleosides(4), L-tryptophan(5), L-phenylalanine(6). The in vitro pharmalogical evaluation results displayed that the above compounds exhibited no inhibitory effects on the proliferation of six tumor cell lines (HCT-8, Bel-7402, BGC-823, A549, A2780 and MCF-7).

CONCLUSIONAmong these obtained compounds, compound 1 was a new compound.

Annona ; microbiology ; physiology ; Ascomycota ; chemistry ; physiology ; Cell Line, Tumor ; Fermentation ; Humans ; Symbiosis