Fig. 2

Effects of chemical and physical factors on the production of extracellular cordycepin by the AoCordy-T1 transformant. The effect of supplementation with purine precursors was investigated by individually adding 1 g/L precursor into the culture medium (A). The culture medium without precursor was used as a control. The effects of culture temperature (B) and agitation rate (C) were sequentially investigated using the selected adenine precursor and optimal temperature, respectively. All data are presented as mean values with standard deviation (SD). Superscript letters (a, b, c, and d) above the bars indicate statistical differences (p < 0.01) between the cultures with one variable factor