Uc. Banerjee et Jp. Srivastava, EFFECTS OF PH AND GLUCOSE-CONCENTRATION ON THE PRODUCTION OF RIFAMYCIN OXIDASE BY CURVULARIA-LUNATA IN A BATCH REACTOR, Journal of biotechnology, 28(2-3), 1993, pp. 229-236
Using a strain of Curvularia lunata, the effects of pH and glucose con
centration in the cultivation medium on the cell growth and enzyme pro
ductivity have been investigated in a batch reactor. An initial pH 6.5
and a control pH 7 during cultivation yielded the best enzyme product
ivity. It was observed that enzyme production was not repressed by hig
h glucose concentration up to 30 g l-1. Precise pH control was necessa
ry to maintain the enzyme production at a desired level when a high su
gar concentration was used. The maximum specific growth rate was 0.25
h-1 when the pH was maintained at 7, while it was only 0.20 h-1 withou
t pH control or when the initial pH of the cultivation medium was adju
sted to 6.5. Antifoam had no significant effect on cell growth and enz
yme activity up to a concentration of 0.5% (v/v), but above this value
the cell growth as well as enzyme activity decreased. C lunata forms
large pellets rather than mycelia when a high sugar concentration was
used and typical disadvantages of submerged culture cultivation of fun
gus appeared.