Immobilization of phytase on zeolite modified with iron(II) for use in the animal feed and food industry sectors

Abstract

Here, we investigated the feasibility of immobilizing phytase onto zeolite modified with iron(II) ions, for application in the feed and food sectors. Zeolites have excellent physical-chemical characteristics, ion exchange capacity, and can act as dietary supplements. The phytase immobilization yield was up to 73 % at pH 7 and ionic strength of 100 mM, with recovered activity higher than 100 %, representing a gain in catalytic activity. The immobilized phytase could be reused, retaining 80 % of its activity in the seventh cycle of phytate hydrolysis, indicating its potential for use in industrial processes. For use in animal feed, the immobilized phytase hydrolyzed the phytate of soybean meal and wheat bran, retaining >50 % of its activity in gastric simulation tests with pH varying from 2 to 7. The results highlighted the innovative combined benefits of phytase, zeolite, and iron for animal nutrition. For application in the food industry, the immobilized phytase could hydrolyze the phytate in soybean milk and be reused in the reaction, retaining ∼50 % of its catalytic activity after 6 cycles. These results indicated the excellent potential of zeolite/iron-immobilized phytase for use in animal feed and the food industry.