Marjan Enshaeieh - Department of Biology, Falavarjan branch, Islamic Azad University, Esfahan, Iran
Azadeh Abdoli - Department of Biology, Esfahan University, Esfahan, Iran
Iraj Nahvi - Department of Biology, Esfahan University, Esfahan, Iran

Microbial lipids have a great similarity to the lipids obtained from plants and animals. Triacylglycerol is the storage lipid in most of eukaryotic cells; this characteristic attracts a lot of attention for using these lipid sources in biodiesel production. Accumulation of neutral lipid composed of triacylglycerol and sterylster is an induced response to environmental stresses in many living organisms. In this situation lipid accumulates as intracellular lipid bodies in yeast cells. Production of microbial oil has more cost than plant’s oil. In this case, reducing the cost of this process must be done by optimization of culture conditions to reach higher production yield. In this study the effect of physical parameters on lipid production of two oleaginous yeasts: Yarrowia lipolytica M7 and Candida sp. was investigated. The mentioned parameters were pH range of 4-7; centrifugation rates of 100, 150, 200 rpm; temperature of 15, 25, 35 and 45ºC and times of incubation of 24, 48, 72 and 96 h. Temperature and time of incubation had a significant effect on lipid production by these strains and optimization of them resulted in increased production of lipid from 25% to 34% in Yarrowia lipolytica M7

physical parameters, oleaginous yeasts, Yarrowia lipolytica M7