No abstract

The decolorization of molasses by 17 different fungi in 2 media was studied. Trichoderma viride showed the highest decolorization yield (53.5%) when cultivated at 30ºC for 7 days in Medium 1 which contained the molasses which was diluted to 40 g/L in distilled water. The other Trichoderma species and Penicillium sp. also gave similar results of 40-45%. Decolorization yield was increased by adding peptone and yeast extract to the production medium except Penicillium sp. Growth rate was not related to decolorization yet pH value was. When the pH decreased below 5.0 after the incubation, the decolorization yield increased. Although reducing sugar in culture broth decreased with decreasing color intensity, there was no connection between protein utilization and decolorizing activity.

In this study, some physiological conditions affecting the activity of xylanase enzyme produced from Trichoderma harzianum 1073 D3 were determined. In addition, stabilization of pH and temperature in liquid and semi-solid state cultivation media were investigated. It was concluded that for maximum xylanase activity, incubation at 60°C in an enzyme incubation medium with pH 5 that contained 1 % xylan was appropriate. The stability studies showed that the enzyme was relatively stable in the pH range 3-7 and retained more than 50 % of its original activity after four months.