Abstract: This study aimed to examine the effect of different extraction techniques on the extraction and hypolipidemic activity in vitro of triterpenoids from Inonotus hispidus (IHT). Five extraction techniques i.e., high shear emulsifier-assisted extraction, ultrasound-assisted extraction, aqueous two-phase extraction, semi-bionic extraction and solvent reflux extraction were evaluated for their influences on the extraction efficiency and cholate binding capacity of IHT. The structure of IHT was analyzed by infrared spectroscopy. The results showed that the extraction efficiency and hypolipidemic activity of IHT were significantly different (P < 0.05) among five extracts; high shear emulsifier-assisted extraction gave the highest extraction efficiency of (3.33 ± 0.02)%, which was 2.64 times as high as that ((1.26 ± 0.05)%) of solvent reflux extraction. The cholate binding capacity of IHT extracted by high shear emulsifier-assisted extraction was the most significant (P < 0.05), and its lipid-lowering activity was dose dependent. At a concentration of 40 mg/mL, the binding capacities for sodium glycocholate, sodium cholate and sodium taurocholate were (1.01 ± 0.03), (0.47 ± 0.04), and (1.31 ± 0.09) μmol/100 mg, respectively, which were 36.53%, 27.92% and 46.33% as compared to those of simvastatin, respectively. Infrared spectroscopy analysis showed that the IHT exhibited the characteristic structure of triterpenoids and the strongest characteristic absorption peak. These findings will provide a theoretical basis for the selection of optimal extraction technique for IHT and the development and utilization of hypolipidemic drugs.

Key words: extraction technique, Inonotus hispidus, triterpeniod, hypolipidemic activity