Breeding a Mortierella Alpina saltant of high ARA production

In order to get a Mortierella Alpina saltant with a higher production of arachidonic acid, the Mortierella Alpina M12 preserved by our laboratory has been conducted for study by 60Co-γ ray. When the irradiation dose is 1, 2 and 3 kGy, the lethality is 73.6%, 80.6% and 93.8% respectively. Biomass, oil content and the production of ARA were considered as the comprehensive evaluation indexes. Through preliminary screening and further screening, we could breed a M12-2-2 saltant. After shaking flask fermentation, its biomass was 30.73 g/L; oil length was 40.51%; ARA content 4.75 g/L, production of which was 1.65 times higher than of original strain. The heritability of the saltant was still stable after ten times of subculturing generations.