Enzymatic production of natural sweetener trilobatin from citrus flavanone naringin using immobilised α‐l‐rhamnosidase as the catalyst

Abstract

SummaryAn efficient and cost‐effective enzymatic production method for preparation of a high‐valued natural sweetener (dihydrochalcone glucoside trilobatin) was developed by the combination of hydrogenation and enzymatic hydrolysis reactions with α‐l‐rhamnosidase as the catalyst in aqueous medium. This technology is adopting the cheap and largely available citrus flavanone naringin as the starting material for trilobatin synthesis, and the present enzymatic technology is possibly utilised by commercial for scale‐up production. The production is a straightforward two‐step process, in which naringin was hydrogenated into naringin dihydrochalcone and followed by removal of the rhamnosyl group of naringin dihydrochalcone by enzymatic hydrolysis using immobilised α‐l‐rhamnosidase as the catalyst. Under optimised conditions, an overall yield of 96% was achieved with a very low loading of α‐l‐rhamnosidase catalyst at 60 °C in a neutral aqueous buffer solution within 2 h. The immobilised α‐l‐rhamnosidase catalyst can be recycled for 10 reactions (90% yield retained).