L-Lactic Acid Production from Canned Pineapple Syrup by Rapid Sucrose Catabolizing Lactobacillus paracasei NRIC 0765

Abstract

Lactic acid production from waste material has received much attention due to its sustainable utilization of biomass and the increasing demand for polylactic acid for use in biodegradable plastics. Canned pineapple syrup, a food processing waste, was utilized as a substrate for L-lactic acid production. To optimize the utilization of sucrose in pineapple syrup, in the presence of glucose and fructose, Lactobacillus paracasei NRIC 0765 was characterized and selected from 158 lactic acid bacteria strains. The selected strain possessed higher lactic acid productivity and sucrose hydrolysis enzyme activity in comparison with other Lb. paracasei strains examined when a sugar mixture was used as the carbon source. The highest lactic acid concentrations achieved were 19 and 93 g l^-1 from 20 and 100 g l^-1 total sugar in pineapple syrup, respectively, without a lag period for sucrose consumption. Using simple cultivation methods, we demonstrate that Lb. paracasei NRIC 0765 has a great capacity to produce L-lactic acid from sugar mixtures containing high sucrose concentrations.