[Breeding of arachidonic acid producing Mortierella sabellina by ultraviolet mutation].

Objective: We obtained a new mutant with higher growth rate and high capability of producing arachidonic acid after protoplast ultraviolet mutation.
Methods: Using dry weight of biomass, microbial total lipid and total arachidonic acid production as evaluation index, we determined time of ultraviolet irradiation by single factor experiment and measured the content of the arachidonic acid by gas chromatography.
Results: When the power of viltalight lamp was set at 20W,exposure distance at 30 cm and exposure time at 80 s, lethality of spores of Mortierella isabellina was 76.4%.
Conclusion: After ultraviolet mutation and repeatedly screening, a mutat of Mortierella isabellina YZ-124 whose arachidonic acid concentration in biomass was 5.76 times of the control strains was obtained.