Noboru Tomizuka

Studies on Lipase from Candida cylindracea :Part I. Purification and Properties

Lipase from Candida cylindracea has been purified by ammonium sulfate precipitation, sodium deoxycholate treatment, ethanol-ether precipitation and chromatography on SESephadex and Sephadex G-100 columns. The purification of the enzyme was 33.4-fold with a yeild of 18.0 % on the basis of activity per weight of protein. The purified enzyme was homogeneous on ultracentrifugation and electrophoresis. Optimum pH for the hydrolysis of olive oil was 7.2 by the assay method using a polyvinylalcohol-emulsified system and 5.2 by the assay method using a shaken system without a macromolecular emulsifier. Optimum temperature was 45°C. The enzyme was stable up to 15°C and in the range of pH from 2.0 to 8.5. Sodium taurocholate showed either an activating or an inhibiting effect at pH 7.0, depending on the sodium taurocholate concentration and on the assay system.

Continuous lipolysis reactor with a loop connecting an immobilized lipase column and an oil-water separator

A continuous lipolysis system is described that consists of a loop connecting a fixed-bed reactor with the immobilized lipase fromPseudomonas fluorescens biotype I and an oil-water separator. In addition to continuous lipolysis, good continuous separation of oil product and water-soluble product and continuous concentration of glycerol can be integrated in this simple reactor.

Triacylglycerol Synthesis from Fatty Acid and Glycerol Using Immobilized Lipase

High free fatty acid (FFA) rice bran oil containing 30-50 % FFA was converted to an oil containing about 75-90 % triacylglycerol (TG) using immobilized lipase. Enzymatic refining of the FFA oil was performed continuously for more than one month using a reactor with two circulation loops, each connecting a fixed bed reactor and a dehydrator. The substrate was the stoichiometric amount of the FFA oil and glycerol required for synthesizing TG. The technology could be applied to synthesizing TG at more than 95 % yield from polyunsaturated fatty acids such as docosahexaenoic acid.