Fatty Acid Compositions of Cellular Lipids of Yeast Grown on Bone Fat and Glucose as a Sole Carbon Source

Abstract

Candida lipolytica yeasts were cultivated on a medium containing pig bone fat or glucose as a sole carbon source. The cell yield was significantly higher in culture grown on bone fat than on glucose medium, and the lipid contents of cells were slightly higher in the yeast grown on bone fat than on glucose. Although, the contents of neutral lipid in total lipid were nearly the same as yeasts on the both media, the bone fat grown cells contained more phospholipids and less glycolipids than the glucose grown cells. The extracted lipids from cultured fluid grown on bone fat contained considerable amount of free fatty acids, and small amount of diacylglycerols and monoacylglycerols. This results suggested that the yeasts grown on fat with a hydrolyzing process of triacylglycerols, and that the hydrolyzed fatty acids from bone fat were incorporated into cell body for use as the composing stuffs of cellular lipids. The neutral lipids of yeast cells composed of triacylglycerols, free fatty acids and diacylglycerols, and then, contained monoacylglycerols and sterol esters as minor ingredients. The major components of polar lipids from yeast cells were considered as phosphatidylethanolamine, phosphatidylcholine, phosphatidylserine, ceramide monohexoside and ceramide dihexoside. The fatty acid compositions of these lipids components from yeast cells were comparatively investigated on the cellular lipids of C. lipolytica grown on bone fat and on glucose media.