Isolation of Cordyceps ophioglossoides L2 from Fruit Body and Optimization of Fermentation Conditions for Its Mycelial Growth

A strain isolated from the fruiting body of a fungus parasitized on Elaphomyces was identified as Cordyceps ophioglossoides based on the morphological characteristics and the analysis of ITS-5.8s rDNA sequence. The optimal medium composition (g·L−1), containing sucrose 66.0, yeast powder 10.0, silkworm chrysalises digest 30.0, MgSO4·7H2O 0.4, and KH2PO4 0.4, was found using fractional factorial design and a central composite design, and the optimization of cultural conditions obtained a result of seed age 6 days, inoculum size 6% (by volume), initial pH 5.6, temperature 24°C, shaking speed 160 r·min−1 by one-factor-at-a-time method. The maximum biomass reached about 20.2 g·L−1 after 90 hours culture under the optimal conditions. Elementary pharmacological activities showed that mycelia of C. ophioglossoides L2 from submerged culture promoted uterus growth in estrogen-depleted mice. In the 15-litre scale-up fermentation, the mycelial biomass was around 19.1 g·L−1, indicating a promising prospect for this biotechnology and the potency to develop its medical value.