Production of linoleic acid-rich lipids in molasses-based medium by oleaginous fungus Galactomyces geotrichum TS61

Abstract

This study was performed to produce linoleic acid-rich lipids in molasses-based medium using locally isolated fungus Galactomyces geotrichum TS61 (GenBank accession: MN749818). The most favorable culture conditions for lipid production were determined as 200 ml/L molasses, 1.5 g/L ammonium sulfate, 1.5 g/L KH2PO4, pH 6, and 8 days incubation time. Maximum values of cell concentration, lipid concentration, and lipid content were 17.1 g/L, 11.9 g/L, and 69.6%, respectively. Polyunsaturated fatty acids (PUFAs) (42.49%) accounted for the majority of fatty acids in this fungus. Linoleic acid (23.67%) was the most abundant fatty acid followed by oleic acid (22.14%). Minor fatty acids were palmitoleic acid, stearic acid, palmitic acid, pentadecanoic acid, and myristic acid. Fatty acid analyses show that lipids of this fungus may be used as food supplement and/or medicinal therapeutics. The lipid production by G. geotrichum in molasses-based medium was investigated for the first time in this study. Practical applications: Galactomyces geotrichum strains are not pathogenic and can be used as starter culture in the preparation of fermented foods. This study demonstrated that the local isolate G. geotrichum TS61 could accumulate high amounts of polyunsaturated fatty acids (PUFAs), especially linoleic acid, when was cultivated in molasses-based simple medium. Due to fatty acid composition, lipids of this fungus may be used as food supplement and/or medicinal therapeutics. Moreover, the high lipid productivity, simple nutrient requirement, and nonhuman pathogenicity can make this fungus an ideal platform for lipid production processes. On the contrary, this fungus can be employed as a tool in bioremediation of molasses since it can tolerate high concentrations of molasses. © 2020 Wiley Periodicals LLC