Antibacterial metabolites production by Lactobacillus plantarum PTCC 1896 in fermented whey and optimization of fermentation conditions for maximum production using RSM

The aim of the present study was to determine the best conditions for production of antibacterial metabolites by Lactobacillus plantarum PTCC 1896 cultured in whey by optimizing incubation time (24, 48 & 72 h), inoculum size (2, 4 & 6%) and MPC concentration (0, 1 & 2%) using Central Composite Design. During fermentation, due to the production of organic acids, pH decreased to 4.83-3.69 and acidity increased to 0.4-0.96%. Inoculum size and MPC concentration had a positive effect on the cell viability and viability decreased with increasing time (p < 0.05). The addition of MPC to whey up to 1% increased the amount of lactose and nitrogenic sources in medium and helped to produce of antibacterial compounds. The optimal fermentation condition to maximum antibacterial metabolites production was 72 h incubation, 1% MPC concentration and 6% inoculum size. The results of LC-MS analysis confirmed the presence of antibacterial peptides in medium. (c) 2024 Elsevier Ltd. All rights reserved..