Sunflower Seed Lipase: Extraction, Purification, and Characterization

• Published in: Preparative biochemistry & biotechnology Vol. 35; no. 1; pp. 37 - 51
• Main Authors: Sagiroglu, Ayten, Arabaci, Nilay
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis Group 01-01-2005
• Subjects: Characterization; Chemical Fractionation - methods; Chromatography, Gel - methods; Dextrans; Drug Storage; Enzyme Activation; Enzyme Stability; Helianthus - enzymology; Helianthus annuus; Heliantus annuus L. substrate specification; Hydrogen-Ion Concentration; Lipase - chemistry; Lipase - isolation & purification; Lipase purification; Seeds - enzymology; Sunflower seed; Temperature
• ISSN: 1082-6068; 1532-2297
• DOI: 10.1081/PB-200041442

A simple procedure for the extraction of the lipolytic activity from sunflower seed has been developed. Various conditions of extraction have been optimized in order to obtain maximum yield of lipase. A new lipase enzyme was purified by the fractional salt precipitation from the supernatant, dialysis on a cellulose membrane, and gel column chromatography on Sephadex G-75. The lipase was monomeric, with an apparent M
r
of 22 kDa and a pI of 8, with the electrophoretic analysis. Kinetics of the enzyme activity versus substrate concentration showed typical lipase behavior, with K
m
and V
max
values of 1.33 mM and 555 U/mg. All triglycerides were efficiently hydrolyzed by the enzyme, but this showed a preference towards triglycerides of natural mono unsaturated fatty acids. The optimum temperature, pH, and incubation time for lipolytic activity were 50°C, 7.5, and 5 min, respectively. The stability of the sunflower lipase was investigated under operational and storage conditions. It was found that this enzyme preserved its lipolytic activity at temperatures between at 35-50°C, alkaline pH, and for a period of about four months.