氮离子注入蛹虫草选育高效富硒菌株的研究

为了更好地开发蛹虫草资源,对蛹虫草菌株富集微量元素硒的培养条件进行了优化,选择最佳参数的低能离子束注入蛹虫草,通过石墨炉原子吸收光谱法检测注入前后菌丝体中硒元素的含量。结果表明:蛹虫草发酵富硒的最优培养条件为蛋白胨质量浓度3 g/100 mL、葡萄糖质量浓度3 g/100 mL、亚硒酸钠质量浓度为8?g/mL、pH值为7,此时,富硒率为21.58%。离子束最佳注入参数为:注入离子为N+,注入能量10 keV,注入剂量1.82×1015 ions/cm2,选育出富集微量元素硒较高的10株菌株,最高富硒率为30.97%,比出发菌株提高了近42%。

Breeding of Cordyceps militaris Strain with High Selenium Enrichment by Low-Energy Ion Beam Implantation

In the present study, investigations were carried out to optimize the medium components for enhanced
enrichment of the dietary microelement selenium (Se) in Cordyceps militaris mycelia. The Cordyceps militaris strain
No.13 preserved in our laboratory was improved by low-energy nitrogen ion beam implantation under optimal operating
conditions to increase Se enrichment in the mycelia. The Se contents in the original and mutant strains were determined
by graphite furnace atomic absorption spectrometry (GFAAS). Results showed that the optimal medium components
for Se enrichment in Cordyceps militaris mycelia were determined as follows: peptone 3 g/100 mL, glucose 3 g/100 mL
and Na2SeO3 8 μg/mL at pH 7.0, resulting in a selenium enrichment rate of 21.58%. The optimal parameters for lowenergy
nitrogen ion beam implantation were achieved at an energy of 10 keV and a dose of 1.82×1015 ions/cm2. Ten
mutant strains showing higher Se-enriching capacity were obtained. The highest Se enrichment rate of 30.97% was
observed, nearly 42% higher than that of the original strain.