Improved Laccase Production On Sugar Cane Bagasse

Filed in archive Energy, Environment and Ecology , Food and Agriculture , Microbiology on November 20, 2006

Researchers have developed a natural, environmentally-friendly method of converting sugarcane bagasse into raw material for paper, through the action of enzymes produced by a filamentous fungus called Pycnoporus cinnabarinus. Since P. cinnabarinus only produce a small amount of laccase with bagasse as substrate, a delignifying enzyme, researchers used ethanol to induce its production.

Ethanol was chosen as a laccase-inducer in this study because of its abundance, its low toxicity and low production cost. The research team moreover showed that if it was put into the system by forced convection at a rate of 7 g of ethanol per m3 (concentration equivalent to 3° of alcohol in the liquid phase), laccase production increased, to a maximum level (90 U per g of dry bagasse support). This amounts to 45 times the yield obtained without ethanol. Moreover, it appeared that little or no ethanol introduced was consumed by the fungus which preferentially uses other sources of carbon, resulting from the bagasse (saccharose) or put in with the substrate (maltose, yeast extracts and so on). It can therefore be recycled in the system or eliminated in a second system associated with it (4).

Such an optimized production of laccase may make paper production from bagasse more commercially viable and lucrative. More details of the study from Institut de Recherche Pour le Développement report (pdf file).