Isolation and identification of active components from Grifola frondosa and its anti‐EV71 virus effect

Abstract BACKGROUND It is reported that anti‐enterovirus 71 (EV71) drugs have some side effects on human health. Notably, fungi plays a crucial role in promoting human health and anti‐virus. Grifola frondosa is a type of large medicinal and edible fungi, rich in active substances. The present study aimed to investigate the anti‐EV71 effect of G. frondosa and the potential active substances. RESULTS In the present study, the water extract of G. frondosa was subjected to ethanol precipitation to obtain the water‐extracted supernatant of G. frondosa (GFWS) and water‐extracted precipitation of G. frondosa . Their inhibitory effects on EV71 virus were studied based on a cell model. The results showed that GFWS had stronger security and anti‐EV71 effects. In addition, the chemical constituents of GFWS were identified by ultra‐high performance liquid chromatography‐tandem mass spectrometry, which were selected for further separation and purification. Three compounds, N ‐butylaniline, succinic acid and l ‐tryptophan, were isolated from GFWS by NMR spectroscopy. It is noteworthy that N ‐butylaniline and l ‐tryptophan were isolated and identified from the G. frondosa fruiting bodies for the first time. Our study found that l ‐tryptophan has anti‐EV71 virus activity, which reduced EV71‐induced apoptosis and significantly inhibited the replication process after virus adsorption. Furthermore, it could also bind to capsid protein VP1 to prevent the virus from attaching to the cells. CONCLUSION l ‐tryptophan was an inhibitor of the EV71 virus, which could be used in infant nutrition and possibly provide a new drug to treat hand, foot and mouth disease. © 2024 Society of Chemical Industry.