Air Atmospheric Pressure Plasma Jet to Improve Fruiting Body Production and Enhance Bioactive Phytochemicals from Mutant Cordyceps militaris (White Cordyceps militaris)

This article investigated the effects of an air atmospheric pressure plasma jet (APPJ) with different treatment times (30 to 120 s) on changes in fruiting body production and biochemical phytochemicals from white Cordyceps militaris (white C. militaris). A low-cost neon transformer was applied to generate the APPJ. An optical emission spectrometer revealed reactive species, including hydroxyl radicals, nitrogen oxide, and atomic oxygen. After treatment with the optimal APPJ conditions, the fresh and dry weights of white C. militaris fruiting bodies significantly increased by 56.7 and 55.4%, respectively. Higher values of cordycepin, adenosine, superoxide dismutase, glutathione S-transferase, and beta-glucan in white C. militaris fruiting bodies were observed after a short time of APPJ treatments. Higher malondialdehyde contents were determined to be associated with high concentrations of APPJ treatments. However, the contents of carotenoids degraded with APPJ treatment. In addition, APPJ treatments significantly enhanced the total phenolic content, flavonoid content, polysaccharide content, 2,2-diphenyl-1-picrylhydrazyl radical scavenging ability, and ferric reducing antioxidant power. Thus, these results suggested that APPJ treatment improves the fruiting body production and nutritional qualities of white C. militaris, which provide health benefits for humans.

Automated summary

This study investigated the effects of different treatment times of an air atmospheric pressure plasma jet (APPJ) on the production of fruiting bodies and phytochemicals of white Cordyceps militaris. Results showed that optimal APPJ treatment significantly increased the fresh and dry weights of white C. militaris fruiting bodies. APPJ treatments also led to higher levels of cordycepin, adenosine, superoxide dismutase, glutathione S-transferase, and beta-glucan in the fruiting bodies, as well as enhanced antioxidant properties. However, carotenoid content decreased with APPJ treatment.