Standardization of reaction kinetics for enzymatic hydrolysis of Indian mustard seed oil for extraction of Erucic acid

摘要

Erucic acid (EA) constitutes about 30-51% of the total fatty acids of Indian mustard (Brassica juncea L. Czem. & Coss.)seed oil. It has got many industrial applications. Hydrolysis of mustard oil by commercial lipase enzyme, Lipozyme TL-100L(source: Novozymes) was investigated for the extraction of EA. The free fatty acids (FFA) present in the mustard seed oil were removed by repeated washing with 90% aqueous ethanol before performing hydrolysis. Hydrolysis was performed at a temperature of 550 C and pH of 5-6 in a water bath shaker for different enzyme concentrations (0.01, 0.02, 0.5, 1.0 and 3.0%) and time periods (30min, 1hr, 3hr, 6hr and 24hr). Released fatty acids were extracted with NaHCO3. This was simple, easy and gave comparatively more recovery of EA. Percentage of FFA as oleic analyzed for different hydrolysis time intervals of 1hr, 2hr, 3hr,4hr, 5hr, 6hrand24hrandwas mmimum at 0.3% and maximum at 0.01% as 1.17 and 4.32 respectively for a time period of 24hr.Percentage of EA in the released acid fraction was analyzed by Gas Chromatography. The analysis revealed that EA content showed a reduction with an increase in the concentration of lipase enzyme used for hydrolysis after threshold equilibrium. EA content was found to be 81.50% (30min); 84.30% (1hr); 90.05% (3hr); 99.30% (6hr); 88.63% (24hr) for 0.01% and 79.59%(30min); 86.49% (1hr); 82.56% (3hr); 80.01% (6hr); 69.43% (24hr) for an enzyme concentration of 0.05%. As lipase, TL-100L is 1, 3 specific therefore with more concentration of enzyme the percentage of EA hydrolysis was decreasing as it started hydrolyzing other relevant positions in triglyceride chain after a certain time period and percentage. It was observed that enzyme concentration of 0.01% for a period of 6hr was the ideal parameter for enzymatic erucic acid extraction from mustard oil.