Affinity foam fractionation of Trichoderma cellulase.

Area of Science:

• Biotechnology
• Biochemical Engineering
• Enzyme Technology

Background:

• Simple foam fractionation struggles to selectively collect cellulase from fermentation broth due to interfering surface-active compounds.
• Cellulase is a key enzyme for biomass degradation, making its efficient recovery crucial for industrial applications.

Purpose of the Study:

• To investigate affinity foam fractionation as an improved method for selective cellulase collection.
• To evaluate the impact of substrate/analog type and concentration on cellulase enrichment.
• To assess the influence of cell presence and growth stage on the fractionation process.

Main Methods:

• Affinity foam fractionation utilizing hardwood hydrolysate, carboxymethyl cellulose (CMC), or xylan hydrolysate as ligands.
• Analysis of foam fractionation properties including speed, stability, volume, and enrichment of filter paper units (FPU).
• Quantification of individual cellulase components (endoglucanases, exoglucanases, beta-glucosidases) and total protein content.

Main Results:

• Addition of substrates/analogs significantly enhanced cellulase hydrophobicity, leading to selective partitioning onto foam bubbles.
• Foamate FPU enrichment exceeded fourfold compared to the initial broth, with E/P values reaching 18.
• Exoglucanases showed the highest enrichment, while beta-glucosidases were least enriched. CMC with low degree of substitution and high molecular weight performed optimally.

Conclusions:

• Affinity foam fractionation is a highly effective technique for purifying cellulase from complex fermentation broths.
• The choice of substrate/analog and its properties (e.g., CMC's MW and DS) are critical for optimizing cellulase recovery and purity.
• This method offers a promising strategy for industrial-scale cellulase production and purification.