Screening and identification of probiotic Lactobacillus for the production of diosgenin from Dioscorea zingiberensis Wright by biotransformation

Abstract

The commonly used methods to produce diosgenin by acid hydrolysis generate large amounts of wastewater and other pollution. Exploring a new environmentally friendly method is becoming urgent. Mild conditions and less pollution are the advantages of biotransformation. Therefore, aiming at exploring the effect of probiotic Lactobacillus on the production of diosgenin via biotransformation, batch studies were performed. Twenty-four strains maintained in laboratory were screened by conversion rate and pH. Based on screening, purification and 16 s rDNA sequences, four probiotic strains were identified and classified. The results indicated that all the strains had biotransformation potential. Among all the strains, four strains, including L20, L35, L83 and L33, performed better, with conversion rates reaching up to 15.12%, 15.83%, 17.07% and 17.47%, respectively. The highest conversion rate, 17.47%, was that of L33 and the lowest one, 7.07%, of L4. Nineteen of the 24 strains achieved more than 10% conversion rate. The pH decreased from 7 to 3-4 after fermentation, reflecting the progress of fermentation and indicating the end of the biotransformation process. Molecular characterization based on 16S rDNA homology of partial sequences confirmed the preliminary identification as L. rhamnosus (L20, L35), L. paracasei (L83) and L. salivarius (L33).

A cleaner production of diosgenin from Dioscorea Zingiberensis Wright biotransformed by Lactobacillus casei

“…Preliminary work screened Lactobacillus casei 83 (L83) as the strain for further research (Shu et al, 2017). The growth stability and high conversion potential were found during the biotransformation experiment of L. casei 83.…”

“…The Lactobacillus 83 was preserved in the School of Food Science & Biological Engineering, Shaanxi University of Science & Technology, which was isolated from commercial dairy product and had been identified as L. casei in our previous study (Shu et al, 2017). The strain was cultured in the MRS (De Man, Rogosa and Sharpe) broth three times each for 24h at 37°C to obtain the active bacterium.…”

“…Inspired by this successful research, Lactobacillus casei had been selected as fermentation strain for biotransformation after a series of screen work (Shu et al, 2017). The aim of this paper is to explore the fundamental fermentation condition of biotransformation by probiotics.…”

Screening and Selection of a New Medium for Diosgenin Production via Microbial Biocatalysis of Fusarium sp.

“…However, the acid is still required, and there is a long way ahead to meet the needs for a low-cost, pollution-free, and energy-saving production process. In recent years, the transformation base of microbial biocatalysis has become increasingly attractive because the acid is replaced by enzymes to cleave the glycosidic bond of saponins in DZW [ 22 , 23 , 24 ]. Microbial biocatalysis is likely a promising alternative to diosgenin production in industrial applications.…”