Improving specific activity of Aspergillus carbonarius polygalacturonase using polymeric membranes

Area of Science:

• Biotechnology
• Enzyme Engineering
• Separation Science

Background:

• Submerged fermentation of Aspergillus carbonarius produces polygalacturonases (PG).
• Crude enzyme broth contains non-enzymatic proteins and impurities, reducing specific activity.
• Efficient purification is crucial for maximizing enzyme utility.

Purpose of the Study:

• To screen microfiltration (MF) and ultrafiltration (UF) membranes for polygalacturonase (PG) purification.
• To develop an integrated membrane process for enhanced PG specific activity and recovery.
• To evaluate different purification schemes for optimal enzyme isolation.

Main Methods:

• Screening of MF (200 nm, 450 nm) and UF (50 kDa) membranes.
• Evaluation of selected membranes under various process conditions.
• Assessment of three different integrated membrane process schemes.
• Analysis of enzyme-specific activity, purity, and recovery.

Main Results:

• MF membranes removed larger non-enzymatic proteins; UF membrane showed limited selectivity.
• A two-stage MF followed by UF process improved PG specific activity by 4.69-fold (5,590 U/mg).
• This integrated process achieved 76% enzyme recovery, removing impurities and enhancing productivity.

Conclusions:

• Appropriate membrane selection and integration are key for enzyme purification.
• The developed MF-UF process effectively purifies polygalacturonases (PG) with high specific activity and recovery.
• Integrated membrane processes offer a viable strategy for efficient enzyme isolation and production enhancement.