Effects of submerged liquid fermentation of Bacillus subtilis WX-17 using okara as sole nutrient source on the composition of a potential probiotic beverage

• Main Authors: Mok, Wai Kit, Tan, Yong Xing, Lyu, Xiao Mei, Chen, Wei Ning
• Other Authors: School of Chemical and Biomedical Engineering
• Format: Article
• Language: English
• Published: 2021
• Subjects: Engineering::Chemical engineering; Antimicrobial Activity; Antioxidant Activity
• Online Access: https://hdl.handle.net/10356/148628
• Institution: Nanyang Technological University

This work aims to produce a functional probiotic beverage using okara as the sole nutrient source. Hence, okara was fermented with Bacillus subtilis WX-17 in submerged liquid fermentation and the supernatant was tested. Metabolomic analysis showed that the nutritional profile of the beverage was enhanced after fermentation. Essential amino acids as well as short-chain fatty acids were significantly (p < .05) upregulated. Total phenolic content and antioxidant content (in terms of DPPH radical scavenging activity) increased by 6.32 and 1.55 times, respectively. After 6 weeks, probiotic viability remains unchanged when stored at 4°C and the cell count is above the minimum dosage to confer health benefits. Antimicrobial activity was also detected against gram-positive bacteria. The findings of this work showed the potential of submerged liquid fermentation of Bacillus subtilis WX-17 using okara as sole substrate to produce a functional and low-cost probiotic beverage.