The activity of some carbohydrases produced by Cochliobolus miyabeanus, the causal fungus of Helminthosporium leaf spot of rice plants

Abstract

1. The present paper deals with the result of the investigations on the relation between the different kinds of culture media and the activity of some carbohydrases, i.e., α-amylase, β-amylase, invertase, and maltase, produced by Cochliobolus miyabeanus. The estimation was made using both intra- and extra-cellular preparations.
2. As to α-amylase and β-amylase, extra-cellular activity is greater than intra-cellular activity. On the contrary, greater activity of intra- than extra-cellular invertase was detected.
3. All the enzymes tested seemed to be the adaptive enzymes because their production markedly increased when the corresponding carbohydrates were added to the media.
4. All of the four carbohydrases were produced more abundantly in the maltose medium than in the other media used.
5. The activity of these enzymes is not always parallel with the growth amount of mycelial mats and the change in pH-value of the culture media.