Lipid-lipase interactions. I. Fat splitting with lipase fromCandida rugosa

Abstract

Commercial dry lipase fromCandida rugosa (formerlyC. cylindracea) was used to catalyze hydrolysis of tallow, coconut oil and olive oil at 26–40 C. A methodology was developed to yield results reproducible within ±10% and to achieve essentially complete hydrolysis. From the hydrolysis data, an empirical relationship was developed that shows that the percentage of free fatty acid formed is almost a linear function of the logarithm of reaction time and the logarithm of enzyme concentration. A 95–98% hydrolysis of the 3 substrates was achieved experimentally in 72 hr, requiring 15 units lipase per milliequivalent (U/meq) of coconut oil or tallow and 6 U/meq of olive oil. The kinetics of lipolysis were determined for all 3 substrates and were found to approximate first order. Lipolysis rate was higher for olive oil than for tallow and coconut oil; no significant differences were observed between the latter 2 substrates. No statistically significant change in overall reaction rate was found when the hydrolysis was run at 26 C, 36 C or 46 C. Although the literature cites calcium or sodium ions and albumin as beneficial adjuvants to enzymatic lipolysis, these additives appeared to have no significant beneficial effect on the reaction. On the other hand, hydrocarbon solvents and nonionic surfactants showed an adverse effect.