Faculty of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, I.R. Iran
Waste water from a molasses alcoholic fermentation plant (MWW) was treated biologically with Phanerochaete chrysosporium. The ability of this white-rot fungus to degrade the dark colored pigments present in MWW and the consequent decrease the effluent's color was examined. The Optimum concentration of MWW for color removal was determined and set at the ratio of 1:10. The color changes during incubation of the diluted MWW at 37úC, show a smooth decreasing trend, without any fluctuation, the highest degree of the decolorization (77%) was obtained in less than five days' of incubation (98 hours) at 37úC. Observation show that the fungus grows in a proper an uniform manner and an integrated cellular mass is formed at the end of the time. The degradative ability of the fungus on the colored substance seems to follow the pattern of the proper growth of the cellular mass. The only ingredient added to the MWW was the basal salt solution (With some modification) which is required for P. chrysosporium growth. Additional carbon source in the form of glucose or sucrose was not required. No pH adjustment was necessary. Based on the results obtained from several studies conducted by others, the main bioagent in the ligninolytic behavior of P. chrysosporium is the enzymes which the expression of the activity lead to hydrogen peroxide production with the simultaneous accumulation of veratryl alcohol in the culture medium. In this study addition of veratryl and hydrogen peroxide to the decolorization medium showed to have no inducible effect. Moreover, the ligninase activity was detected in the MWW culture medium at is highest level of decolorization (77%) was found to be 224 UL-1.