Cultural characteristics of Cordyceps militaris strain ‘Yedang 3’ on various media and nutritional conditions

Abstract

The effects of environmental and nutritional requirement such as temperature, pH, different media, carbon, nitrogen, and carbon-to-nitrogen ratio on the mycelial growth of Cordyceps militaris strain ‘Yedang 3’ were studied. The optimum temperature and pH for the growth of mycelium were 20-25oC and pH 6-7, respectively. Out of ten media tested, mushroom complete media (MCM) was the best medium for fast mycelial growth, and Sabouraud’s dextrose agar yeast extract (SDAY), malt extract yeast extract agar (YMA) also were favored. The color and shape of colonies varied in different media. The best carbon sources for mycelial growth were fructose, mannitol, and sucrose, whereas the best nitrogen sources were tryptone and peptone. However, mycelia grew slowly in inorganic nitrogen compounds such as NH4Cl, (NH4)2SO4, NH4NO3, and NaNO3. The optimum C:N ratio observed on the culture media was 30-40 range. These results provided basic information on cultural characteristics of vegetative growth and might be useful for spawn production in Cordyceps militaris.