# Saccharification and Ethanol Production of Corn Wastes Using a Locally Produced Trichoderma atroviride Enzymatic Cocktail

## TL;DR

This study shows that a homemade enzyme mix from Trichoderma atroviride can efficiently convert corn waste into ethanol, offering a low-cost solution for biofuel production.

## Contribution

The study introduces a low-cost, locally produced Trichoderma atroviride enzyme cocktail for efficient cellulosic ethanol production from corn waste.

## Key findings

- The homemade enzyme cocktail achieved high β-glucosidase and xylanase activity suitable for lignocellulose conversion.
- Adding 1% Tween 20 increased total reducing sugars by 91.4% in pretreated corn cob hydrolysate.
- Alcoholic fermentation of the hydrolysate achieved a theoretical conversion yield of 83.48%.

## Abstract

This study investigated
the efficiency of a homemade
enzymatic
cocktail from Trichoderma atroviride (HTM strain) in the saccharification of corn straw (CS) and corn
cob (CC), aiming at cellulosic ethanol production. The blend of cellulases
and hemicellulases, obtained through solid-state fermentation, exhibited
high levels of β-glucosidase (374.91 U/g) and xylanase (920
U/g). The β-glucosidase from this cocktail presented optimal
activity and stability at pH and temperature ranges suitable for lignocellulose
bioconversions (4.5–5.0 and 50 °C) and was employed in
the saccharification of alkali-pretreated CC and CS (PTCC and PTCS,
respectively). The fed-batch hydrolysis, performed with 30 CBU/g (cellobiase unit) cellulose and 35% solid (w/v), released
the highest concentration of total reducing sugars (TRS) in PTCC (15.86
g/L). When 1% Tween 20 was added to the reaction mixture, a total
of 30.37 g/L TRS was detected in PTCC hydrolysate, representing an
increase of 91.4% in comparison to the hydrolysis without the surfactant.
The alcoholic fermentation of the PTCC hydrolysate resulted in a theoretical
conversion yield of 83.48%. These data indicated the feasibility of
using T. atroviride as a low-cost enzymatic
source and the combined strategy of fed-batch mode and surfactant
in improving the hydrolytic and fermentative efficiencies.