Cellulose nanostructures obtained using enzymatic cocktails with different compositions.

Area of Science:

• Biomass valorization
• Green chemistry
• Materials science

Background:

• Enzymatic hydrolysis of lignocellulosic biomass typically aims for complete cellulose depolymerization into sugars.
• Cellulose nanostructures offer unique material properties and sustainable processing advantages.
• Optimizing enzymatic cocktails is key to controlling nanocellulose production and properties.

Purpose of the Study:

• To investigate the impact of different commercial cellulase enzyme cocktails on nanocellulose production.
• To compare enzymatic cocktails designed for complete versus partial biomass saccharification.
• To evaluate the role of auxiliary enzymes, particularly xylanases, in nanocellulose formation.

Main Methods:

• Comparison of commercially available cellulase enzyme cocktails (complete and partial saccharification) on eucalyptus cellulose pulp.
• Analysis of nanocellulose properties including crystallinity, surface charge (zeta potential), and dimensions.
• Quantification of glucose production as a measure of saccharification efficiency.

Main Results:

• All tested enzymatic cocktails produced nanocellulose structures.
• Complete saccharification cocktails were more efficient in glucose coproduction (87% cellulose conversion).
• Auxiliary enzymes, especially xylanases, significantly improved nanostructure crystallinity (up to 79%), surface charge (-30.9 mV), and uniformity (80-350 nm).

Conclusions:

• Enzymatic cocktails used for biomass saccharification can be adapted for simultaneous nanocellulose production and glucose release.
• Xylanase activity is crucial for improving nanocellulose properties, even in partially saccharifying cocktails.
• This dual-product approach is compatible with integrated biorefinery concepts.