There are three types of lactic
acid: L-lactic acid, D-lactic acid and D,L-lactic acid that is a mixture of D-and L-isomer (racemic
mixture) [9]. Racemic mixture form is always produced by chemical synthesis, whereas an optically pure
L- or D-lactic acid can be obtained by microbial fermentation from renewable resources depending on the
strain chosen [16], [17]. Nowadays, lactic acid is considered the most potential feedstock monomer for
chemical conversions into potentially useful chemicals including PLA, which serves as biodegradable
commodity plastic and biocompatible polymer [16]. The optical purity of lactic acid is an important
properties of PLA, an optically pure L or D lactic acid will be give better properties of PLA than racemic
DL-lactic acid. PLA obtained from optical pure lactic acid can be polymerized to a high crystalline PLA
that is suitable for commercial uses [10].