Enzymatic ring opening polymerization of both enantiomers of lactide was performed in toluene. The eROP was kinetically improved by solvent assisted method (by TEA) and gave 6 time faster reaction.

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A kinetic model of the simultaneous saccharification, protein hydrolysis, and fermentation (SSPHF) process for lactic acid production from wheat flour has been developed. The model describes the bacterial growth, substrate consumption, lactic acid production, and maltose hydrolysis. The model was fitted and validated with data from SSPHF experiments obtained under different dilution rates. The results of the model are in good agreement with the experimental data. Steady state concentrations of biomass, lactic acid, glucose, and maltose as function of the dilution rate were predicted by the model. This steady state analysis is further useful to determine the operating conditions that maximize lactic acid productivity.

Consumption of hexoses/pentoses and production of lactic acid by Lactobacillus bifermentans were investigated in optimized culture medium and hemicellulosic hydrolyzates. The hydrolyzate used had the following composition (expressed in gL -1 ): xylose 50 ± 5 gL -1 ; glucose 18 ± 3 gL -1 ; arabinose 29 ± 5 gL -1 . The immobilization experiments were conducted with microbial cells entrapped in calcium alginate beads. The results indicate that maximum concentrations of lactic acid were produced after 54 h of fermentation. All glucose and arabinose in wheat bran hydrolyzate were consumed during fermentation. Only xylose was not completely consumed. The substrate consumption rate was 3.2 gh -1 , 1.9 gh -1 , 1.6 gh -1 respectively for glucose, arabinose, and xylose. The optimized culture condition gave a lactic acid concentration and metabolic yield of 62.77 gL -1 and 0.83 gg -1 . These parameters improved to 41.3 gL -1 and 0.47 gg -1 respectively, when cell free was used.