Study On The Triterpenoids From The Fungus Ganoderma Lucidum And Their Inhibitory Effects On α-Glucosidase

Objective:Ganoderma lucidum (Polyporaceae) has been used in folk medicine throughout the world since ancient times, especially Asian countries. G. lucidum is registered in the Chinese Pharmacopoeia (2010) together with Ganoderma sinense for the treatments of neurasthenia, insomnia, anorexia, dizziness, chronic hepatitis, hypercholesterolemia, coronary heart disease, hypertension, and carcinomas. But the bioactive substances of Ganoderma lucidum have not been clarified. This study is aim to investigate the bioactive substance, which could promote the drug development of Ganoderma lucidum.Methods:1. The extracts of Ganoderma lucidum was diluted with water and extracted with CHCl3. The CHCl3 extract was subjected to column chromatography on silica gel and HPLC successively. As a result,13 compounds were obtained.2. The structures of 13 compounds were determined by various spectroscopic data, including UV, ESI-MS, HRESI-MS,1H-NMR,13C-NMR, and 2D-NMR.3. The a-Glucosidase inhibitory effects of compounds 1-13 were evaluated in an in vitro bioassay.Results:13 lanostane triterpenoids (1-13) were isolated from the fruiting body of Ganoderma lucidum, which was a folk medicine distributed in China. Their structures were elucidated by HRESIMS, ESIMS,1D-NMR,2D-NMR spectroscopic data. Additionally, compound 1,2 were new compounds, and compound 11 was isolated from Ganoderma lucidum for the first time. All of compounds were elucidated as (1) Ganoderic acid X1, (2) Ganoderic acid X2, (3) Ganoderic acid C, (4) Deacetyl-Ganoderic acid F, (5) Methyl ganoderate E, (6) Ganoderic B, (7)11α-hydroxy-3,7-dioxo-5α-lanosta-8,24(E)-dien-26-oic acid, (8) Lucienic acid A, (9) 20(21)-dehydrolucidenic acid A, (10) 7-hydroxy-3,11,15-trioxo-lanosta-8-en-24→20s Lactone, (11) Lucidone D, (12) Methyl lucidenate D2, and (13) Lucidenic acid F.The α-Glucosidase inhibitory effects of compounds 1-13 were evaluated in an in vitro bioassay. As a result, compound 2,10,11 could inhibit α-Glucosidase moderately.Conclusion:13 new phenolic constituents 1-13 were obtained from the fruiting body of Ganoderma lucidum. Their structures were elucidated on the basis of spectroscopic analyses, such as NMR, UV, IR, HRESIMS, ESIMS. Compound 1,2 were new compounds, and compound 11 was isolated from Ganoderma lucidum.Furthermore, in an in vitro bioassay, all compounds were tested for inhibitory effects against α-Glucosidase. Compounds 2,10, and 11 showed moderate inhibitory effects.This study suggested that lanostane triterpenoids were the major constituents of the fruiting body of Ganoderma lucidum. It was worthy to investigate these chemical constituents as bioactive substances.