深黄被孢霉高产花生四烯酸菌株的紫外诱变原生质体育种

【目的】为了获得一株生长活力较强, 产花生四烯酸能力强的菌株。【方法】我们以干菌重、微生物油脂产量和花生四烯酸产量为评价指标，采用紫外线诱变原生质体的方法。我们利用单因素实验确定了紫外线诱变剂量, 并采用气相色谱分析了花生四烯酸含量。【结果】试验结果表明：紫外灯功率20 W，照射距离30 cm，照射时间40 s，其致死率为79.5 %。【结论】经过诱变及菌种筛选所获得高产菌株YZ-124的生物量为36.5 g/L，微生物油脂含量为19.2 g/L，花生四烯酸含量为4.72 g/L，花生四烯酸产量比出发菌株AS3.3410提高576 ％，并且遗传性能稳定。

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 30cm and exposure time at 80s, 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.