Production of Ginsenoside F2 by Using Lactococcus lactis with Enhanced Expression of beta-Glucosidase Gene from Paenibacillus mucilaginosus

摘要

This study aimed to produce a pharmacologically active minor ginsenoside F2 from the major ginsenosides Rbl and Rd by using a recombinant Lactococcus lactis strain expressing a heterologous beta-glucosidase gene. The nucleotide sequence of the gene (BglPm) was derived from Paenibacillus mucilaginosus and synthesized after codon optimization, and the two genes (unoptimized and optimized) were expressed in L. lactis NZ9000. Codon optimization resulted in reduction of unfavorable codons by 50% and a considerable increase in the expression levels (total activities) of beta-glucosidases (0.002 unit/mL, unoptimized; 0.022 unit/mL, optimized). The molecular weight of the enzyme was 52 kDa, and the purified forms of the enzymes could successfully convert Rbl and Rd into F2. The permeabilized L. lactis expressing BglPm resulted in a high conversion yield (74%) of F2 from the ginseng extract. Utilization of this microbial cell to produce F2 may provide an alternative method to increase the health benefits of Panax ginseng.