Enhancing laccase production by white-rot fungus trametes hirsuta SSM-3 in co-culture with yeast sporidiobolus pararoseus SSM-8.

Due to wide application of laccase, many researchers have shown great interest in over production of white-rot fungi laccase by co-culture. In this study, a white-rot fungus Trametes hirsuta SSM-3, and a yeast Sporidiobolus pararoseus SSM-8 were isolated and identified from Mulberry fruit. The capacity of S. pararoseus to enhance laccase production was remarkable in T. hirsuta, yielding 31777 +/- 742 U/L, about 9.9 times higher than the result from the monoculture. The stimulatory factor in the S. pararoseus cells might be temperature-sensitive. The laccase production was enhanced by oil-extract of S. pararoseus and beta-carotene induction. The amylase activity was decreased rapidly when strain S. pararoseus SSM-8 was inoculated. The glucose deprivation was occurred both in the mono-culture and co-culture process, and S. pararoseus propagated slowly in co-culture all the time. Native-PAGE revealed an increase of laccase-1(lac-1) level and a laccase-3 (lac-3) in the co-culture. Therefore, it was concluded that competition for resources between the co-cultured microbes leaded to amylase decreasing and the enhanced production of laccase. This conclusion was helpful for the development of laccase fermentation industry because it provided an effective, simple and economic method to improve the yield of laccase.