Comprehensive chemical analysis of triterpenoids and polysaccharides in the medicinal mushroom Antrodia cinnamomea

Abstract

Antrodia cinnamomea is a precious medicinal mushroom used in adjuvant treatments of cancer. Triterpenoids (25R/S-ergostane epimers and Δ^7,9/Δ⁸-lanostanes) and polysaccharides are its major bioactive constituents. Quality control of this mushroom is difficult, due to a lack of effective analytical methods. In this study, a series of methods were established to analyze A. cinnamomea. The ergostane- and lanostane-type triterpenoids were extracted by 50% and 100% methanol, respectively, and were then analyzed by ultra-high performance liquid chromatography coupled with diode-array detection and quadrupole time-of-flight mass spectrometry (UHPLC/DAD/qTOF-MS). In total 49 compounds, including 34 ergostanes and 10 lanostanes, were characterized by comparing with 31 reference standards or by analyzing the UV and MS spectral data. Furthermore, the contents of 18 major triterpenoids, including 10 ergostanes and 8 lanostanes, were determined by UPLC/UV or supercritical fluid chromatography coupled with mass spectrometry (SFC/MS, for 25R/S-antcin A) within 16 min. This is the first time that the contents of pure optical forms for 5 pairs of 25R- and 25S-ergostane epimers (antcins A, B, C, H, and K) were determined. On the other hand, the polysaccharides in A. cinnamomea were analyzed by ion chromatography coupled with pulsed amperometric detection (IC/PAD) after acid hydrolysis, and the contents of 7 monosaccharides were determined. Finally, the established methods were applied to the analysis of 15 batches of A. cinnamomea. Samples derived from different cultivation techniques could be distinguished according to the contents of triterpenoids. The UPLC/UV, SFC/MS and IC/PAD methods established in this work provided powerful tools to evaluate the quality of A. cinnamomea.