植酸酶的研制与应用

Preparation and Application of Phytase

植酸酶能将饲料中不被动物吸收的植酸(肌醇六磷酸)水解,释放出可被畜禽利用的肌醇和游离磷。由于植酸螯合饲料中的铁、钙、锌等离子,并抑制淀粉酶、胰蛋白酶和胃蛋白酶的活性,降低了动物体对矿物质和蛋白质的吸收。添加植酸酶可降低饲料成本,解除植酸的抗营养作用,提高磷、蛋白质和矿物元素的利用率,减少环境污染。该项目由黑曲霉经原生质体诱变获得了高产植酸酶菌株A-828,并建立了完整的发酵工艺和后处理工艺。

Phytic acid ( inositol hexaphos- phate) , which cannot be assimilated by animal in feed, can be hydrolyzed by phytase to liberate myo- inositol and free phosphorus which can be assimila- ted. For chelating metal ions such as calcium, iron and zinc and inhibiting activity of amylase, trypsase and pepsase, phytic acid leads small assimilation of mineral matters and protein. However, adding phytase can reduce the cost of feed, relieve the anti- nourishment function of phytic acid, increase utiliza- tion rate of phosphorus, mineral matters and protein and decrease environmental pollution. A high yield- ing phytase strain A-828 has been obtained via muta- genesis by protoplast from Aspergillus niger. The whole fermentation process and after-treatment process has been set up.