phytase It is an enzyme and passes several steps of purification ..Definitely  Aspergillus niger is GRAS 

Thank your for the answer Dr Abd, Can I use this enzyme for food preparation to decrease the level of phytate or it is used only for feed preparation ?

Certainly possible ,Because Phytate has been dubbed the anti-nutrient, but it’s also a beneficial phytonutrient. Phytate binds with minerals and prevents their absorption, possibly leading to deficiencies, especially if your diet is high in fiber and whole-grain foods.