Ale. Mahmoud, DIFFERENT FACTORS AFFECTING GROWTH AND AMYLASE PRODUCTION BY FUNGI INHABITING POULTRY FEEDS, Journal of basic microbiology, 33(3), 1993, pp. 187-192
Extracellular amylase synthesis by Aspergillus flavus and A. .fumigatu
s, isolated from poultry feeds, was studied in stationary liquid mediu
m. Maximum mycelium and extracellular amylase were produced after 7 da
ys of incubation at 30-degrees-C and after 5 days at 3 5-degrees-C by
A. flavus and A.fumigatus, respectively. Optimal amylase yield was obt
ained at pH 8 and 6 by the two fungi, respectively. Amylase production
did not depend on the presence of starch in the growth medium but its
inclusion in the medium enhanced amylase production by A. fumigatus.
Sucrose appeared to be a poor carbon source for amylase synthesis by t
he test fungi. Growth on varying nitrogen sources showed that glycine
promoted amylase production by A.flavus while yeast extract achieved m
aximum enzymatic yield by A. fumigatus.