| Popis: |
Eggshells capacity as supporting material for immobilisation of Candida rugosa Type VII lipase (CRL) was tested. Different parameters for the immobilisation of eggshells were studied including the temperature (30-50°C), pH of buffer the solution (pH 5-8), particle size of the eggshells (≤1mm, 1-2mm and 2-4mm), immobilisation time (1-4 hr) and glutaraldehyde concentration (0.30-3.00%, v/v). The best immobilisation conditions obtained were ≤1mm size of the eggshells added with 0.75% of glutaraldehyde at pH buffer 6. The immobilisation time taken was 3 hr at 50°C. Then optimal conditions for the ester synthesis of butyl butyrate were achieved using 2.0g of the immobilised lipase loading that reacted at 30°C using a 0.2 molar ratio of the substrate for 3 hr. Under optimal conditions (immobilization and esterification), 93.3% of conversion yield of butyl butyrate was obtained. Furthermore, the synthesized immobilized CRL lipase demonstrate that it was highly reusable as it retained 50% of the initial activity after 31 cycles. |
