ABSTRACT
ABSTRACT The aim of this study was to optimize the dextranase production by fungus Pochonia chlamydosporia (VC4) and evaluate its activity in dextran reduction in sugarcane juice. The effects, over the P. chlamydosporia dextranase production, of different components from the culture medium were analyzed by Plackett-Burman design and central composite design. The response surface was utilized to determine the levels that, among the variables that influence dextranase production, provide higher production of these enzymes. The enzymatic effect on the removal of dextran present in sugarcane juice was also evaluated. It was observed that only NaNO3 and pH showed significant effect (p<0.05) over dextranase production and was determined that the levels which provided higher enzyme production were, respectively, 5 g/L and 5.5. The dextranases produced by fungus P. chlamydosporia reduced by 75% the dextran content of the sugarcane juice once treated for 12 hours, when compared to the control treatment.
Subject(s)
Models, Statistical , Saccharum/metabolism , Dextranase/biosynthesis , Hypocreales/enzymology , Temperature , Dextrans/metabolism , Culture Media/metabolism , Electrophoresis, Polyacrylamide Gel , Enzyme Activation , Fruit and Vegetable Juices/analysis , Chemical Fractionation/methods , Hydrogen-Ion Concentration , NitratesABSTRACT
Maximum dextranase synthesis was obtained by the locally isolated F. moniliforme when grown aerobically on a medium containing dextran, 2% as a carbon source, ammonium nitrate in 500 mg N/l as nitrogen source, adjusted to pH 5.5 and inoculated with 5% inoculum in the form of a 4 days mycelium after 8 days incubation. The fungus gave 66.45 units/ml dextranase activity with 9.53 units/mig mycelium. The optimum enzyme activity was found to be at pH 5 and temperature 55°