Microbial lipids (Single cell oil; SCO) are produced by oleaginous microorganisms such as yeasts, molds, algae and bacteria and SCO production has drawn attention as a subject of industrial and scientific research for many years. Currently, SCOs attract much importance as raw materials of functional oils for food, drugs and healthcare products and feedstock for biodiesel production.

The production of SCO by microorganisms has several advantages compared to other oil resources such as plants and animals including independency of fermentative processes from climate and, more importantly, avoiding the competition with resources that can be used as food by the use of waste products and accomplishment of environmentfriendly production. In addition, as a result of strain development by “recombinant biotechnology” applications production of high volumes of different, precious and rare SCOs is ensured.

High fermentation costs prevent future applications, and lead to uncertainity in terms of industrial production potential. Therefore, various hydrophilic and hydrophobic substrates are evaluated for SCO production. The efficiency of SCO production is affected by environmental factors such as type of carbon source, nitrogen source, temperature, pH, time, the amount of dissolved oxygen and is dependent on the microorganism species and strain. The amount of lipid produced and fatty acid composition in single cell oil production also vary depending on the environmental factors and fermentation strains.