EFFECT OF IMMOBILIZATION PROTOCOL ON CATALYTIC ACTIVITY OF CRL IMMOBILIZED ONTO OIL PALM LEAVE-SILICA-MAGNETITE SUPPORT

Purpose: The purpose of the study was to establish the optimal conditions required for the attachment of Candida rugosa lipase (CRL) onto silica extracted from ash of acid treated oil palm leaves, for maximum catalytic efficiency. Methodology: Six different concentrations of CRL solution ranging from 1 mg/mL to 6 mg/mL, immobilization time of 4, 8, 12, 16, 20 and 24 h as well as immobilization temperature of 4, 25, 30, 35 40 and 45  were independently investigated. In this study, the parameter to be investigated was varied while others were fixed. The effectiveness of the immobilization protocol were assessed using four catalytic parameters – protein loading, immobilization yield, specific activity and ester yield.   Statistical analysis was performed using one way ANOVA (IBM SPSS -20.0) software while significant differences within ranges in a parameter, if any was given as p  0.05. Findings: The study revealed that the optimal values of concentration of CRL solution, immobilization time and immobilization temperature required to immobilize CRL onto SiO2-MNPs derived from oil palm leave were 5. 0 mg/mL, 16 h and 25  respectively. At this optimal conditions, protein loading (33.3, 38.1, 20.5 mg/g), immobilization yield (57.8, 70.0, 59.0 %), specific activity (74.6, 63.5, 72.2 U/g) and ester yield (85.0, 74.1, 85.5 %) respectively were achieved. Recommendation: Optimization of the immobilization protocol for immobilizing CRL onto silica support extracted from the highly abundant oil palm leave – an agricultural biomass, will not just produce a biocatalyst of with high catalytic efficiency but would circumvent the environmental pollution arising from dumping of large quantities of the biomass into the ecosystem. It is recommended from the findings of this study that 5.0 mg/mL CRL solution be immobilized onto glutaraldehyde activated SiO2-MNPs support matrix derived from oil palm leave for 16 h at 25.