Resveratrol and arctigenin production from polydatin and arctiin respectively by a thermostable β-glucosidase from Thermotoga maritima

Abstract

For preparation of resveratrol and arctigenin from peanut hulls and arctium lappa fruits, respectively, a recombinant β-glucosidase (TmBglA) from hyperthermophile Thermotoga maritima was purified and characterized. The hydrolytic activity was the highest at 90 °C and pH 6.2 for arctiin with Km of 1.61 mM and kcat of 197.4 s−1, and 90 °C and 5.8 for polydatin with Km of 0.38 mM and kcat of 47.6 s−1. The enzyme produced 215.4 mg L−1 resveratrol and 355.7 mg L−1 arctigenin from 400 mg L−1 polydatin and 540 mg L−1 arctiin after 60 min of incubation at 80 °C, with capable of hydrolyzing up to 92.1 and 94.9% of polydatin and arctiin, respectively. The enzymatic hydrolysis of peanut hulls and fructus arctii displayed a conversion yield of 3.8 and 0.33 mg resveratrol and arctigenin per gram of substrate material flour, respectively. Of the reported β-glucosidase, TmBglA exhibited the highest thermostability, kcat, kcat/Km, and conversion productivity for hydrolyzing polydatin and arctiin, and has great potential applications in functional food and medicine production.