Oil production by Candida curvata and extraction, composition, and properties of the oil

TLDR: A strain of the yeast C. curvata was grown in cheese whey permeate under conditions that allowed for oil production as mentioned in this paper, but the efficiency of conversion to oil was reduced.

Abstract: A strain of the yeast C. curvata was grown in cheese whey permeate under conditions that allowed for oil production. The N-C ratio of the fermentation medium influenced the amount of oil produced. Concentrated permeate could be used as a substrate, but the efficiency of conversion to oil was reduced. The yeast grew well and produced oil in several different types of whey and milk permeates and also in nonsterile systems. The lipid of C. curvata amounted to approximately 50% of its dry weight and could be extracted by sequential treatment with ethanol, hexane, and benzene. The extraction with benzene was necessary for good yields even though nearly all the material extracted with benzene was soluble in hexane. The lipid was 80-90% triglyceride, contained little free fatty acid, and could be degummed by traditional methods. The triglyceride was 30.4% palmitic, 0.84% palmitoleic acid, 11.4% stearic, 51.0% oleic, 6.2% linoleic, and 0.4% linolenic acid. The saturated acyl groups were almost completely on the sn-1 and 3 positions of the glycerol. The oil melting point was -10 to 22 degrees. No tocopherol was detected and the oil oxidized at a rate similar to that for soybean oil at 55 degrees. The oilmore » contained a variety of linear hydrocarbons and 4 sterols. The polar lipids include phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, and phosphatidic acid.« less