Anotace:
This study includes isolation and characterization of local isolates of Rhodotorula glutinis. From twenty-seven samples, three isolates showed yeast morphology and pigmented with orange-red. These isolates were subjected to biochemical tests and the results revealed that the three isolates have the characteristics of Rhodotorula glutinis. Effects of different incubation periods on growth and single cell oil (SCO) production showed that a maximum lipid content and productivity was 12.27 g/L and 64.74%, respectively after 4 days of incubation by the strain Rhodotorula glutinis WS9. A study of effect of different carbon sources revealed that the best carbon source for maximum oil production and oil productivity was glucose, which gave 12.15 g/L and 64.38%, respectively. Glucose concentration of 80 g/L gave a maximum oil content (13.76 g/L) and oil productivity (73.97%), whereas glucose 40 g/L concentration supported a maximum yeast growth (18.90 g/L). Ammonium sulfate was the best nitrogenous source to get a maximum dry biomass, lipid content and lipid productivity which reached to the 18.92 g/L, 12.21 g/L and 64.53%, respectively. 1.0% (w/v) ammonium sulfate was optimum for lipid content and lipid productivity which gave 14.96 g/L and 71.88%, respectively. Initial pH effects study revealed that the optimal initial pH was 6.5 which recorded 18.99 g/L, 12.23 g/L and 64.40% for dry biomass, lipid content and productivity, respectively.