CORN GLUTEN HYDROLYSIS BY ALCALASE: KINETICS OF HYDROLYSIS

Abstract

In the present study, the reaction kinetics of corn gluten hydrolysis by Alcalase, a bacterial protease produced by Bacillus licheniformis, was investigated. The reactions were carried out for 10 min in 0.1 L of aqueous solutions containing 10, 20, 30, 40, and 50 g protein L⁻¹ corn gluten at various temperature and pH values. The amount of enzyme added to the reaction solution was 0.25% (v/v). Also, to determine decay and product inhibition effects for Alcalase, a series of inhibition experiments were conducted with the addition of various amounts of hydrolysate. For each experimental run, both the amount of hydrolysis (meqv L⁻¹) and the soluble protein amount (g L⁻¹) were investigated with respect to time, and the initial reaction rates were determined from the slopes of the linear models that fitted to these experimental data. The kinetic parameters, K_m and V_max were estimated as 53.77 g L⁻¹ and 5.94 meqv L⁻¹min⁻¹. The type of inhibition for Alcalase was determined as uncompetitive, and the inhibition constant, K_i, was estimated as 44.68% (hydrolysate/substrate mixture).

Keywords:

• Alcalase
• Corn gluten
• Hydrolysis kinetics
• Product inhibition

Acknowledgments

The authors gratefully acknowledge Novoyzmes and Cargill for their support.

Notes

^a Units for V_max: meqv L⁻¹min⁻¹ for that obtained from amount of hydrolysis data, g L⁻¹min⁻¹for that obtained from soluble protein concentration data.

^a Unit for V_max: meqv L⁻¹min⁻¹.

^a Units for : meqv L⁻¹min⁻¹ for that obtained from amount of hydrolysis data, g L⁻¹min⁻¹for that obtained from soluble protein concentration data.