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The optical purity of non-steriodal anti-inflammatory drugs (NSAIDs) is one of the concerns in pharmaceutical industries, since the enantiomers demonstrate distinct physical and chemical characters. The production of single enantiomer of NSAIDs through dynamic enzymatic kinetic resolution (DEKR) has been pinpointed as among the promising approach developed in recent years. The substrate conversion and product enantioselectivity could be improved as compared to the conventional kinetic resolution. A combination of enzymatic kinetic resolution (EKR) and base-catalyzed racemization process can guarantee racemic substrate conversion of more than 80 %. The utilization of hollow-fiber membrane as enzyme-mediated reactor significantly improves the DEKR operation. This chapter describes the DEKR of a racemic ibuprofen in enzymatic membrane reactor (EMR), which system has been intensively investigated. From the experimental work, high conversion of the substrate (>90 %) and opticaly pure product (ee P > 95 %) have been obtained. The kinetic model was integrated with that of the mass transfer in the cylindrical hollow-fiber module in order to simulating the entire system by the interaction between the EKR and racemization reaction. The product ((S)-ibuprofen acid) was crystallized and the preliminary toxicity studies were carried out. In conclusion, DEKR of NSAIDs is a promising technology for the production a single enantiomer of NSAIDs.

Phenol and its derivatives exist in various types of industrial effluents, and are known to be harmful to aquatic lives even at low concentrations. Conventional treatment technologies for phenol removal are challenged with long retention time, high energy consumption and process cost. Enzymatic treatment has emerged as an alternative technology for phenol removal from wastewater. These enzymes interact with aromatic compounds including phenols in the presence of hydrogen peroxide, forming free radicals which polymerize spontaneously to produce insoluble phenolic polymers. This work aims to extract peroxidase from agricultural wastes materials and establish its application for phenol removal. Peroxidase was extracted from jicama skin peels under varying extraction conditions of pH, sample-to-buffer ratio (w/v %) and temperature. Experimental results showed that extraction process conducted at pH 10, 40% w/v and 25oC demonstrated a peroxidase activity of 0.79 U/mL. Elevated temperatures slightly enhanced the peroxidase activities. Jicama peroxidase extracted at optimum extraction conditions demonstrated a phenol removal efficiency of 87.5% at pH 7. Phenol removal efficiency was ~ 97% in the range of 30 - 40oC, and H2O2 dosage has to be kept below 100 mM for maximum removal under phenol concentration tested.