Hydrolysis of citrus peel naringin by recombinant α‐L‐rhamnosidase from Clostridium stercorarium

Abstract The citrus fruit processing industry generates substantial quantities of waste rich in glycosylated phenolic substances such as naringin, which are a valuable natural source of polyphenols as well as L‐rhamnopyranose. Naringin is the major polyphenol in bitter orange peel and its hydrolysis by α‐ L ‐rhamnosidase (EC 3.2.1.40) catalyzes the cleavage of the terminal rhamnosyl groups to form prunin and rhamnose. In this work, a recombinant α‐ L ‐rhamnosidase from C. stercorarium was shown to be suitable for narigin hydrolysis. The recombinant rhamnosidase was found to be relatively stable at 60 °C, and a residual activity close to 50% after 180 min of incubation was demonstrated. The purified enzyme established hydrolysis of naringin extracted from citrus peel waste (CPW). The result indicated that recombinant α‐ L ‐rhamnosidase has industrial applicability and is an interesting candidate for producing rhamnose from citrus peel. Copyright © 2010 Society of Chemical Industry