This study deals with the extraction and recovery of invertase enzyme from tomato using an aqueous two-phase system as a mild and effective method for enzyme separation. Several systems composed of polyethylene glycol with citrate and phosphate salts were compared to select the most efficient system. The effects of temperature, pH, polymer concentration, salt concentration, and polymer molecular weight on recovery efficiency were studied. The results showed that lower temperature helped maintain enzyme stability and improved its separation between the two phases.
pH also had a clear effect on the enzyme charge and its interactions with the system components, which affected its partitioning and recovery efficiency. The best system was polyethylene glycol 4000 with sodium citrate, which achieved a recovery of 89.8% and a partition coefficient of 8.8. The extraction conditions were statistically optimized to obtain the best combination of factors affecting enzyme recovery. After selecting the best system, the effects of sodium chloride and magnesium chloride were studied to increase recovery efficiency. The addition of sodium chloride increased the recovery to 95.8%, while magnesium chloride achieved the highest recovery of 96.7%. The results of this study confirm that the aqueous two-phase system is a promising and effective method for recovering invertase from tomato with high efficiency.
