Effect of Medium Components on Lipase Activity in "Koji"

Abstract

Lipase activity were examined in "Rice koji", "Soybean koji", "Okara koji" and "Sardine koji", molded with Aspergillus oryzae. Soybean koji", "Okara koji" and "Sardine koji" exhibited the lipase activity, while, the activity was negligible in "Rice koji".
Futhermore, effect of olive oil and pepton on the lipase activity was examined by using a mycelium. When A. oryzae was cultivated in the malt extract-dextrose medium, the lipase activity was not detectable. While, when the mycelium subsequently cultivated in the medium containing pepton, the lipase activity was high, but low in the medium containing olive oil. Lipase activity was mainly influenced by the nitrogenous compound in "Koji' such as pepton.