Hydrolysis of plant biomass at different growth stages using enzyme cocktails for increased fermentable hydrolysates

Henry P. Oamen of the College of Life and Environmental Sciences, School of Biosciences, University of Exeter, UK and of the Department of Plant Biology and Biotechnology, University of Benin, PMB 1154, Benin City, Nigeria research was on the hydrolysis of plant biomass at different growth stages using enzyme cocktails for increased fermentable hydrolysates.

In this experiment, optimum experimental conditions for the enzymatic hydrolysis of grass at different stages of growth were obtained by using the Taguchi methodology. Rye grass silage and three growth stages of Italian rye grass samples were used to determine optimum hydrolysis conditions. Five factors (pretreatment, enzyme composition, incubation temperature, pretreatment time, pH) influencing the hydrolysis process were studied at the individual and interactive levels.

All selected experimental factors influenced the hydrolysis of grass. At the individual level, pretreatment of grass with NaOH and enzyme composition had the greatest influence (75% and 14.7% of the variance respectively) on enzymatic hydrolysis. Incubation temperature, pretreatment time and pH had influences of 8.1%, 2.2% and 0.055%, respectively. pH and incubation temperature had the most significant interaction effect (65.6%) on enzymatic hydrolysis. The factors with the least individual influence had the most significant interaction effect on enzymatic hydrolysis.

Hydrolysis was improved when optimised conditions were applied to different growth stages of Italian rye grass.