Highly efficient production of D-lactate by Sporolactobacillus sp. CASD with simultaneous enzymatic hydrolysis of peanut meal.

Highly efficient D-lactate production by Sporolactobacillus sp. strain CASD was demonstrated in this study. Peanut meal was found to be a better nutrient than yeast extract, soybean meal, soybean peptone, corn steep, liquor beef extract, and ammonium sulfate in the production of D-lactate. To improve the utilization of peanut meal, the material was enzymatically hydrolyzed and simultaneously utilized as the nitrogen source in D-lactate fermentation. Very high D-lactate production (207 g/L) was obtained using 40 g/L of peanut meal in 30-L fed-batch fermentation, with the average productivity of 3.8 g/(L·h) and optical purity of 99.3%. The production of such a high concentration of optically pure D-lactate by strain CASD, with the simultaneous enzymatic hydrolysis of peanut meal and fermentation, represents a new cost-efficient and integrated method for D-lactate production using agricultural by-products.