**5. Conclusion**

Soybean curd residue which is the residue of *Tofu* production was used for nutrients for production of a lipopeptide antibiotic, iturin A in solid state fermentation(SSF) using *Bacillus subtilis*. As the main carbon sources of soybean curd residue were insoluble fiber, we expected that *B. subtilis* produced the soybean curd residue-degrading enzymes. Among insoluble fibers in soybean curd residue, hemicellulose was mainly degraded by *B. subtilis* during SSF. Xylan, a major hemicellulose in plant cell wall was degraded by *B. subtilis*, and two enzymes which showed xylanase activity were purified and identified as endo-1,4-βxylanase and α-amylase. As productivity of iturin A in soybean curd residue was almost equivalent to that in glucose medium, this study gave a possible way to use soybean curd residue in higher and economical production of lipopeptides.
