Comparison on decolorization of palm oil mill effluent by biological, chemical and physical methods

Decolorization of palm oil mill effluent pretreated by enzyme from Aspergillus niger ATCC 6275 was investigated. The culture filtrate after separation of suspended solids was used for decolorization by biological, chemical and physical methods. Results indicated that the chemical method (using coagulant) was more effective than the biological method (using commercial peroxidase, two strains of white-rot fungi Phanerochaete chrysosporium and Coriolus versicolor) and physical method (using activated carbon, pararubber seed and sand filter). Studies on the effect of coagulant concentrations on decolorization revealed that using the combination of 10 ml/l polyferric sulphate and 10 g/l calcium oxide gave the highest color removal of 84.5% and organic matter (in term of chemical oxygen demand, COD) removal of 86.5%

Optimization of lipase entrapment in alginate gel bead for palm olein hydrolysis

Lipase from Pseudomonas sp. was entrapped by drop-wise addition of an aqueous mixture of alginate and the biocatalyst to hardening solution of CaCl2 for the purpose of palm olein hydrolysis. Effects ofimmobilization conditions including alginate concentration, CaCl2 concentration, enzyme concentration and bead size on immobilized yield, immobilized lipase activity and recovery of activity (specific activity ratio ofentrapped lipase to free lipase) were investigated. An increase in alginate concentration raised immobilized yield, but decreased immobilized lipase activity and recovery of activity. CaCl2 concentration in the testedrange of 50-200 mM had slight effects on immobilized yield, immobilized lipase activity and recovery of activity. In contrast to immobilized lipase activity, immobilized yield and recovery of activity decreased withincreasing enzyme concentration. With increasing bead size, immobilized lipase activity and recovery of activity decreased due to mass transfer resistance whereas immobilized yield was unchanged. The optimumcondition for lipase entrapment in alginate gel bead was alginate concentration at 2% (w/v), CaCl2 concentration at 100 mM, enzyme concentration at 30 U/ml and bead size at 2 mm. Under this entrapmentcondition, 8.11 U/ml of immobilized lipase was obtained with 95.2% of immobilized yield and 22.2% of recovery of activity