Evaluation of In Vitro Antioxidant and Antihyperglycemic Activities of Extracts from the Lion's Mane Medicinal Mushroom, Hericium erinaceus (Agaricomycetes).

To obtain activated fractions, the ethanol extract (EE) of Hericium erinaceus was fractionated to get petroleum ether fraction (PEF), chloroform fraction (CF), ethyl acetate fraction (EAF) and n-butanol fraction (NF). Total phenol content (TPC) and total flavonoid content (TFC) in the fractions were determined, and the phenolic compounds were characterized and quantitated using liquid chromatography-electrospray ionization-mass spectrometry. Meanwhile, in vitro antioxidant and antihyperglycemic activities of extracts were evaluated respectively based on their 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging abilities as well as α-amylase and α-glucosidase inhibitory abilities. Finally, the inhibition modes of extracts on α-amylase and α-glucosidase were detected by kinetic assay. The results showed that TPC, TFC, and the content of phenolic compounds in the extracts were different. EAF contained the highest contents of both TPC and TFC and exhibited strongest inhibitory effects on α-amylase and α-glucosidase, with half maximal inhibitory concentration (IC50) values of 0.47 ± 0.02 and 0.63 ± 0.01 mg/mL, respectively. However, CF showed the highest scavenging abilities on DPPH and ABTS radicals, with IC50 values of 2.30 ± 0.12 and 1.72 ± 0.06 mg/mL, respectively. Correlation analysis showed that the high antihyperglycemic ability of EAF may be related to ferulic acid, whereas cinnamic acid may be responsible for the high antioxidant ability of CF. Furthermore, all fractions were found to exert inhibition on α-amylase and α-glucosidase in mixed-type and competitive manners, respectively. Overall, these results suggest that H. erinaceus has a potential effect on antihyperglycemic and antioxidant activity.