灰树花菌株的复壮及常压室温等离子体诱变

【背景】实验室所用灰树花菌株系长期继代培养,易出现菌株退化。【目的】通过菌株复壮的方法实现菌株的生物学活性及性状的恢复,并借助高效诱变仪对菌株实施诱变,以期得到活性更高、遗传稳定的诱变株。【方法】分别以PDA加富培养基和PDA-板栗壳培养基为培养基质,采用尖端菌丝分离法进行菌株复壮,得到回复菌株原有的生物学活性及性状的复壮株P-2,为了进一步提高菌株的高产性能,利用常压室温等离子体(atmosphericroomtemperatureplasma,ARTP)诱变技术作用于复壮株P-2菌丝体,最终筛选到一株性能优良、遗传稳定性高的诱变株b-35。【结果】复壮后的菌株P-2菌丝干重和多糖含量分别达到1.18%和19.01%,较出发株分别提高35.17%和35.11%,通过发酵罐验证菌株的发酵周期由48h缩短至32h,菌株发酵活性及效率明显提高。诱变株b-35菌丝干重和多糖含量分别达到1.56%和25.07%,较复壮株P-2分别提高了40.15%和39.33%。【结论】ARTP诱变方法易操作、无污染且诱变效率高,是获得灰树花高产菌株的重要方式。

Rejuvenation and atmospheric room temperature plasma mutagenesis in breeding of Grifola frondosa

Background] Grifola frondosa showed degenerated characteristics due to long-term subculture. Objective] To restore the biological activity and characteristics of G. frondosa through rejuvenation method, and to acquire strains possessing improved vitality and genetic stability through mutagenesis by high efficient apparatus. Methods] Hyphae tip isolation method was utilized for rejuvenation of the strains cultivated in PDA enriched medium and PDA-chestnut shell medium respectively. Rejuvenated strain P-2 regained its biological activity and properties. To further improve its production performance, P-2 was subjected to ARTP mutagenesis, and a mutant b-35 with promoted performance and high genetic stability was obtained finally. Results] The dry weight of mycelium and polysaccharide content of the strain P-2 were 1.18% and 19.01%, and the growth rates were 35.17% and 35.11% respectively compared with that of the original strain. Cultivation of P-2 in fermentation tank indicated that the fermentation cycle was shortened to 32 h from 48 h, showing significant improvement of fermentation activity and efficiency. Mycelium dry weight and polysaccharide content of the mutant b-35 reached 1.56% and 25.07%, 40.15% and 39.33% higher than that of P-2. Conclusion] ARTP mutagenesis method was proved to be an important way in breeding of high yield Grifola frondosa because it is easily operated, pollution-free and efficient.