Production of linolenic acid by Mortierella isabellina grown on octadecanol.

The production of linolenic acid in mycelial lipids reached 0.31 mg/ml of culture broth when Mortierella isabellina was cultivated in a medium consisting of 2% octadecanol, 1% yeast extract, and 25 mmol/L of Mg2+ at 23 degrees C for 5 days. Cultivation conditions were studied, and the results showed that (i) a suitable concentration of Mg2+ in the medium caused an increase in mycelial mass as well as linolenic acid production; (ii) when incubated at 23 degrees C, maximal linolenic acid productivity was reached, although a higher content of the acid in total fatty acids was found at the lower temperature; (iii) the effect of substrate concentration on linolenic acid yield showed that the latter increased with concentration of substrate, and maximal linolenic acid yield was obtained with concentrations of 2% octadecanol and 1% yeast extract.