Lactic acid Production from Hydrolysate of Green Seaweeds

In this study, we investigated the possibility of using seaweed as an alternative carbon source for lactic acid production. For this purpose, the chemical composition analysis (proximate analysis, ultimate elemental analysis, and mineral analysis) and acid hydrolysis of seaweeds and corn stover were examined. Furthermore, lactic acid fermentations of seaweeds and corn stover hydrolysate were carried out using Lactobacillus strains. The lactic acid yield, which is defined as the ratio of the lactic acid production to total sugar consumption, varied depending on biomass. Among the strains tested, L. casei showed the highest lactic acid yield (0.54 g g-1) from corn stover hydrolysate, followed by Enteromorpha prolifera hydrolysate (0.41 g g-1), Capsosiphon fulvescens hydrolysate (0.23 g g-1), and Ulva pertusa hydrolysate (0.18 g g-1). However, lactic acid production (4.0 g L-1) from E. prolifera hydrolysate was higher than that from corn stover hydrolysate (3.2 g L-1). The results shown in this study indicate that E. prolifera is competitive with lignocellulosic biomass such as corn stover in terms of lactic acid production under the same conditions (acid hydrolysis and fermentation) and that seaweed can be used as a feedstock for industrial production of chemicals.