JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY, cilt.30, sa.3, ss.475-485, 2015 (SCI-Expanded)
Lipases (triacylglycerol hydrolases, EC 3.1.1.3) are hydrolytic enzymes that can catalyze the hydrolysis of the ester bond of long chain acylglycerols at the oil-water interface. In this study; the effects of initial pH, initial sucrose concentration, activators and inhibitors on Candida utilis yeast, lipase enzym are searched. It is qualified that the optimum pH value for growth rate of Candida utilis yeast and production of lipase enzym is 4. Molasses which is a remnant of sugar industry is used as a main carbon source in nutrient media that is prepared for experimental studies in which lipase enzym activity is worked out. In the media in which molasses is used as a main carbon source, it is observed that lipase enzym activity increases with the increase of initial sucrose concentration. Soybean oil, corn oil, olive oil, sunflower oil and canola oil are added to the nutrient media and when the additive effect of enzym activity is observed it is found out that the highest activity increase is 788,5 U/L with the addition of 1,25% soybean oil. The result is that; Cu(II) and Ni(II) metal ions in the fermantation media lower the lipase activity severly and besides, lowering effect of Ni(II) is much more than that of Cu(II).