An inexpensive medium for production of arachidonic acid by Mortierella alpina

Abstract

The production of arachidonic acid was studied in the fungus Mortierella alpina using an inexpensive medium. Glucose derived from maize starch hydrolysate was the sole carbon source and defatted soybean meal and sodium nitrate were the nitrogen sources. Optimal arachidonic acid yield (1.47 g l-1) was observed at a glucose concentration of 100 g l-1. Various treatments of defatted soybean meal to extract soluble nitrogen nutrients were evaluated. Alkali extract was the most effective for arachidonic acid production. A mixture of soybean alkali-extract protein and sodium nitrate was an excellent nitrogen source for fungal growth, lipid accumulation, and arachidonic acid production. A maximum yield of 1.87 g arachidonic acid l-1 was obtained with a soybean protein concentration of 4.6 g l-1 and a sodium nitrate concentration of 2.3 g l-1.