Optimization of the components concentrations of the lactoperoxidase system by RSM

Area of Science:

• Biochemistry
• Enzymology
• Food Science

Background:

• The lactoperoxidase system (LP-s) is a natural antimicrobial agent.
• Enhancing LP-s antibacterial activity is crucial for food preservation and safety.
• Understanding the interactions of LP-s components is key to optimizing its function.

Purpose of the Study:

• To model the effects of glucose oxidase (GOD), glucose, lactoperoxidase (LPO), and pH on thiocyanate (SCN-) peroxidation using response surface methodology (RSM).
• To determine optimal concentrations of LP-s components for maximal SCN- peroxidation.
• To enhance the antibacterial efficacy of the LP-s.

Main Methods:

• Response surface methodology (RSM) was employed to design experiments.
• The study modeled the effects and interactions of GOD, glucose, LPO concentrations, and pH on SCN- peroxidation.
• Experiments were conducted at 4°C and 25°C in a phosphate buffer with a fixed SCN- concentration.

Main Results:

• Optimized concentrations for GOD (85.5 IU l⁻¹), glucose (8 mmol l⁻¹), and LPO (3927.5 IU l⁻¹) at pH 6.5 were determined for both temperatures.
• SCN- peroxidation was more efficient at 25°C than at 4°C.
• The optimized LP-s demonstrated bacteriostatic effects on Listeria monocytogenes and bactericidal effects on Pseudomonas fluorescens.

Conclusions:

• Optimal combinations of LPO, GOD, glucose, and pH maximize SCN- peroxidation.
• RSM provides a better understanding of LP-s functioning and component interactions.
• Enhanced antimicrobial efficiency of LP-s is achievable through optimized component ratios.