Biotransformation of Geniposide into Genipin by ImmobilizedTrichoderma reeseiand Conformational Study of Genipin

Abstract

Trichoderma reeseiQM9414,Trichoderma viride3.316,Aspergillus nigerM85, andAspergillus nigerM92 were screened for hydrolyzing geniposide into genipin.T. reeseiwas selected according to theβ-glucosidase activity of the fermentation broths using geniposide as a substrate.T. reeseiwas immobilized by embedding method using sodium alginate as the carrier. Geniposide was hydrolyzed by immobilizedT. reeseiat 28°C (200 rpm) for 34 h, and the yield of genipin was 89%. The product was purified and identified by UV, IR, EIMS, and1H-NMR. Since there were two sets of signals in1H-NMR spectra, a series of experiments were performed and verified that the existence of two conformations was the main reason. Generally, biotransformation of geniposide into genipin by immobilizedT. reeseiprovides a promising solution to the genipin production.