Time-dependent change in Reishi (Ganoderma lingzhi) triterpenoids in culture with rumen fluid

The purpose of this study was to investigate the time-dependent change in Reishi (Ganoderma lingzhi) triterpenoids in rumen fluid. G. lingzhi fruiting bodies were milled and incubated in a tube with rumen fluid for 0, 4, 8, 12, 24, and 48 h at 39°C. After incubation, all the tubes were freeze-dried and extracted by ethanol. The contents of 18 triterpenoids in the ethanol extract were quantitated by liquid chromatography-mass spectrometry (LC-MS/MS). Based on the results, triterpenoids were categorized into three groups: (1) rapid decrease, indicating reductions of more than 50% within 8 h; (2) mild decrease, with reductions of more than 50% within 48 h; and (3) minimal change, even after 48 h, there was not much change. Ganoderic acid C6, DM, H, K, and TR as well as Ganoderenic acid D were classified in (1); Ganoderic acid LM2 and T-Q as well as Ganoderiol F in (2); and Ganoderic acid A, B, C1, C2, I, and TN; Gnoderenic acid C; and Ganodermanontriol in (3). In addition, a relationship between chemical structure and metabolic speed was observed in some cases. The results of this study revealed that G. lingzhi triterpenoids are digested and metabolized at different speeds in ruminant fluid.