Procedure to determine enzyme inhibitors activity in cereal seeds

Abstract

This work established a procedure for commercial fungal amylase usage as indicator of enzyme inhibitors presence in cereals, intending to screening antifungal resistance properties in cereals. Firstly, the inhibitive effects of oat, wheat and rice protein extracts were assessed against different amylase sources. It was found that the fungal amylase (Fungamyl®) was the most affected by the inhibition property of the extracts. The best conditions for inhibitor-extract-enzyme interaction were established (pH, temperature, starch concentration). Inhibition kinetic allowed their classification as mixed inhibitors. A high quocient (1.7) was observed between enzyme inhibition and Fusarium graminearum multiplication reduction. Fungamyl® amylase demonstrated its potential to detect the protein inhibitor presence in different cereals and might be employed in screening natural resistance to fungal contamination.