Isolation, Identification and Optimization of Crude Oil Degrading Micromycetes for Biosynthesis of Poly Unsaturated Fatty Acids

Abstract

Poly unsaturated fatty acids (PUFAs) participate in activities of all organisms from energy source to structural components. Disruption of metabolism results in diseases like atherosclerosis and obesity. In this work, optimal conditions to production of arachidonic, eicosapentaenoic and gamma- linolenic acids has been conducted in the oil degrading fungi-Cephalosporium humicola IE, Mucor globosus 11 and Pythium irregulare LX isolated from soils in Absheron peninsula, Azerbaijan. The fermentation process carried out at physicochemical conditions, carbon and nitrogen sources, temperature, pH, rate of inoculum, enzyme activity, exogenous fat and phosphate; as well as the stressful situations. Growth in crude oil as optimal carbon source showed that suitable nitrogen was peptone for lipid biosynthesis. In stable temperature the optimal lipid productionoccurred at 28°C, whereas in “temperature shifting technique”, greater yields occurred at 28°C for 5 days followed by at 15°C for 2 days. C/N ratio ranged from 4 to 64 and the optimal medium for production was composed of 2.0% glucose and 0.25% yeast extract, with addition of 0.1% KH2PO4 at neutral pH with 3% inoculum. Although the activities of the enzymes varied among the fungi, but the developmental profiles for all enzymes were practically similar. Additive fat and phosphate accelerated growth and enhanced PUFA production. Data showed that the procedure of adaptation of fungi motivated the increase of the rate of membrane phospholipids with a high quantity of PUFAs. This research is considered to be object of PUFA production as food supplements.