Effect of poly(vinyl acetate–acrylamide) microspheres properties and steric hindrance on the immobilization of Candida rugosa lipase

• Published in: Bioresource technology 2012-11, Vol.124, p.233-236
• Main Authors: Zhang, Dong-Hao, Yuwen, Li-Xia, Li, Chao, Li, Ya-Qiong
• Format: Article
• Language: English
• Subjects: Acrylamide - chemistry; Candida - enzymology; Candida rugosa; Enzymes, Immobilized - metabolism; Hydrophobic/hydrophilic; Immobilized enzyme; Lipase - metabolism; Microspheres; Polyvinyls - chemistry; Specific activity; Spectroscopy, Fourier Transform Infrared; Steric hindrance
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2012.08.083

► Carrier hydrophobicity/hydrophilicity could affect lipase immobilization. ► To enhance lipase activity, lipase/carrier should be rationally designed. ► The optimal immobilized lipase held higher specific activity than free lipase. Poly(vinyl acetate–acrylamide) microspheres were synthesized in the absence or presence of isooctane via suspension polymerization and utilized as carriers to immobilize Candida rugosa lipase. When the hydrophobic/hydrophilic surface characteristics of the microspheres were modified by changing the ratio of vinyl acetate (hydrophobic monomer) to acrylamide (hydrophilic monomer) from 50:50 to 86:24, the immobilization ratio changed from 45% to 92% and the activity of the immobilized lipase increased from 202.5 to 598.0U/g microsphere. Excessive lipase loading caused intermolecular steric hindrance, which resulted in a decline in lipase activity. The maximum specific activity of the immobilized lipase (4.65U/mg lipase) was higher than that of free lipase (3.00U/mg lipase), indicating a high activity recovery during immobilization.