Corn Straw Residue: a Strategy for Lipase Immobilization

Area of Science:

• Biocatalysis
• Enzyme immobilization
• Biomaterials

Background:

• Enzyme immobilization enhances enzyme stability and reusability.
• Lipases are crucial biocatalysts in various industrial applications.
• Developing cost-effective and efficient immobilization supports is essential.

Purpose of the Study:

• To investigate the immobilization of Candida rugosa lipase (CRL) onto untreated corn straw residue.
• To characterize the corn straw support and the immobilization process.
• To evaluate the activity, stability, and kinetic properties of the immobilized CRL.

Main Methods:

• Characterization of corn straw (chemical, morphological, textural).
• Enzyme immobilization via adsorption.
• Assessing immobilized enzyme activity, thermal stability, and storage stability.
• Kinetic analysis using pseudo-second-order and Langmuir models.

Main Results:

• Corn straw exhibits favorable characteristics (isoelectric point, surface hydroxyls, porous structure) for lipase immobilization.
• Immobilization followed pseudo-second-order kinetics and Langmuir isotherm, indicating monolayer chemical adsorption.
• Immobilized CRL showed increased optimum temperature, reduced optimum pH, and decreased substrate affinity.
• The immobilized enzyme demonstrated good thermal stability and satisfactory storage stability (12% activity loss over 60 days).

Conclusions:

• Untreated corn straw is a suitable and cost-effective support for CRL immobilization.
• The adsorption mechanism is favorable and efficient for enzyme immobilization.
• Immobilized CRL retains significant activity and stability, showing potential for industrial applications.