Potential Use of Lactobacillus casei TISTR 1500 for the Bioconversion of Palmyra Sap to Lactic acid

Abstract

Production of lactic acid from palmyra sap by fermentation has been studied using Lactobacillus casei TISTR 1500 as the producer organism. The effects of the physical and chemical properties of palmyra sap were determined. The pH, water content, total soluble solids, total sugars, and total nitrogen were 4.3, 86.2%, 14.8°Brix, 134.0 g L^-1, and 0.03 g L^-1, respectively. The fermentation took place in a flask under static conditions. The variation of 10.0-134.0 g L^-1 total sugars in the palmyra sap was carried out at 37°C for 24 h in a basal medium. The final lactic acid concentration, dry cell weight and productivity increased with the increment of total sugars of palmyra sap concentrations up to 134.0 g L^-1. The kinetic parameters of the palmyra sap of 134.0 g L^-1 total sugars revealed that the specific growth rate (μ) was 0.05 h^-1, the maximum productivity (R_M) was 2.02 g lactic acid L^-1 h^-1, the cellular yield coefficient (Y_X/S) was 0.20 g cell g^-1 sugar and the lactic acid yield (Y_P/S) was 0.78 g g^-1.