Roridin E, produced by Podostroma cornu-damae, is a mycotoxin with anticancer activity. To increase the content of roridin E, submerged culture conditions were optimized using response surface methodology. Three factors, namely, medium initial pH, incubation time and agitation speed were optimized using a Box–Behnken design. The optimum submerged culture conditions to increase the content of roridin E included a medium with an initial pH of 4.0, an incubation time of 12.90 days, and an agitation speed of 63.03 rpm. The roridin E content in the submerged culture, under the aforementioned conditions, was 40.26 mg/L. The findings of this study can help lower the current price of roridin E and promote its related research.

ABSTRACT
INTRODUCTION
MATERIALS AND METHODS
    Reagents and standards
    Microorganism
    Culture media
    Submerged Culture
    Determination of mycelial dry weight
    Determination of roridin E
    Experimental design by the RSM
    Statistical analysis
RESULTS AND DISCUSSION
    Effect of various media on mycelial dry weight androridin E production
    One-factor-at-a-time experimentEffect of incubation time on roridin E production
    Effect of initial pH on roridin E production
    Effect of agitation speed on roridin E production
    Optimization of roridin E production by the RSM
REFERENCES

• Dong Hwan Lee(Division of Environmental Forest Science and Institute of Agriculture & Life Science, Gyeongsang National University)
• Si Young Ha(Division of Environmental Forest Science and Institute of Agriculture & Life Science, Gyeongsang National University)
• Ji Young Jung(Division of Environmental Forest Science and Institute of Agriculture & Life Science, Gyeongsang National University)
• Jae-Kyung Yang(Division of Environmental Forest Science and Institute of Agriculture & Life Science, Gyeongsang National University) Corresponding author