Simple dissolution-reaction model for enzymatic conversion of suspension of solid substrate

Area of Science:

• Biochemical Engineering
• Enzymatic Catalysis
• Process Optimization

Background:

• Industrial bioconversion processes often utilize substrate suspensions.
• Existing literature lacks quantitative models for optimizing these suspension-based reactions.
• Lack of predictive models hinders efficient process design and scale-up.

Purpose of the Study:

• To develop a simple quantitative model for bioconversion processes involving poorly soluble substrates in suspension.
• To incorporate both substrate dissolution kinetics and enzymatic reaction kinetics into a unified model.
• To validate the model's predictive capability for optimizing such processes.

Main Methods:

• A mathematical model was formulated combining substrate dissolution and enzymatic reaction rates.
• The model was experimentally tested using alpha-chymotrypsin-catalyzed hydrolysis of dimethyl benzylmethylmalonate suspension.
• Key kinetic parameters, including mass transfer coefficient (k(L)), substrate solubility, and reaction rate constant, were determined independently.

Main Results:

• The developed model accurately predicted the overall rate of the dissolution-reaction process using independently determined parameters.
• The model's predictions aligned well with experimental observations for the hydrolysis of dimethyl benzylmethylmalonate.
• The model's applicability extends to various poorly soluble substrates, enzymes, and solvents.

Conclusions:

• The proposed model provides a quantitative framework for optimizing bioconversion processes involving substrate suspensions.
• It successfully rationalizes the interplay between mass transfer and enzymatic reaction kinetics.
• This approach offers a valuable tool for the rational design and optimization of industrial bioconversion technologies.