铬离子对蛹虫草子实体生物量及化学成分的影响

蛹虫草是一种具有多种生物功能的药用真菌,近年来在金属离子富集方面受到学者的广泛关注,但对蛹虫草富集Cr³⁺的能力及其相应的生理反应尚无文献报道。为此,本研究利用含有不同Cr³⁺浓度的燕麦培养基培养蛹虫草子实体,分别对蛹虫草子实体生物量及子实体中虫草素、腺苷、虫草酸、麦角甾醇、铬离子含量等指标进行了测定。结果表明,除麦角甾醇随着培养基中Cr³⁺浓度的增加而降低之外,其余指标均呈现先增加后降低的变化趋势。700 mg/L Cr³⁺处理时,子实体干、鲜重和铬离子含量达到最大值,分别比对照组增加36.85%、35.53%和202.12%;当Cr³⁺达1 500 mg/L时,虫草素和腺苷含量达到最大值,分别比对照组高94.61%和530.29%;虫草酸含量和多糖含量分别在1 100 mg/L和1 200 mg/L Cr³⁺处理时达到最大值,分别比对照组高123.62%和21.39%。本研究首次探讨了蛹虫草子实体富集Cr³⁺的能力以及Cr³⁺处理下的子实体生物量和部分次生代谢产物含量的变化规律,为进一步研究蛹虫草富集铬离子机制提供了理论依据,为富铬蛹虫草功能性食品的研发奠定了基础。

Effects of enriching chromium ion on biomass and chemical composition of fruit body of Cordyceps militaris

Cordyceps militaris is an important medicinal fungus with various biological functions. In recent years, its ability to accumulate metal ions has received extensive attention by researchers. However, the ability of C. militaris to accumulate Cr³⁺ and the corresponding physiological responses have not been reported in the literature. In this study, oat media containing different concentrations of Cr³⁺ were used to culture C. militaris fruit body, and the biomass and content of adenosine, cordycepic acid, ergosterol and Cr³⁺ in C. militaris fruit body were determined. The results showed that the measured indexes manifested a trend of increasing first and then decreasing with the increase of Cr³⁺ concentration in the medium, except for ergosterol content which showed a reduction trend. The dry and fresh weight and Cr³⁺ content of fruit body reached the maximum value when the medium contained 700 mg/L Cr³⁺, having increased by 36.85%, 35.53% and 202.12% as compared with those of the control, respectively. The cordycepin content and adenosine content reached the maximum value when Cr³⁺ concentration reached 1 500 mg/L, being 94.61% and 530.29% higher than those of the control, respectively. The cordyceps acid content and polysaccharide content reached the maximum value at Cr³⁺ concentration of 1 100 mg/L and 1 200 mg/L, respectively, being 123.62% and 21.39% higher than those of the control, respectively. In conclusion, this study revealed for the first time the Cr³⁺ enrichment ability of C. militaris fruiting body, and the variation of biomass and content of some secondary metabolites in fruiting body under Cr³⁺ treatment. Further study of Cr³⁺ enrichment mechanism of C. militaris is needed for laying a foundation of developing chromium ion-rich C. militaris functional products.