Nguyễn Văn Tính * Nguyễn Thị Hà

* Tác giả liên hệ (vantinhnguyen1106@gmail.com)

Abstract

Phytase is a group of enzymes that is able to release phosphorus from phytate so that it can be easily digested, so phytase is largely used in animal feed. Aspergillus fumigatus ET3 appeared to have high potential for phytase production. In this study, the growth conditions to improve the enzyme production of this new Afumigatus ET3 were investigated. The result showed that wheat was a suitable substrate for biosynthesis of phytate from this fungus. Furthermore, optimum conditions for high phytase production from this species were pH 4, spore density about 108/mL, incubation time of 2 days and incubation temperature of 35oC.
Keywords: Aspergillus fumigatus, extracellular phytase, phytate

Tóm tắt

Phytase là enzyme có khả năng giải phóng phosphorus từ phytate, khiến phosphorus trở nên dễ hấp thu nên được dùng phổ biến trong thức ăn gia súc. Trong nghiên cứu trước đó, chủng nấm Aspergillus fumigatus ET3 được xem có tiềm năng trong việc sản sinh enzyme phytase. Việc thiết lập được môi trường nuôi cấy thích hợp nhất để thu nhận hàm lượng phytase cao để hạ giá thành sản xuất enzyme từ chủng nấm mốc này là rất cần thiết. Kết quả nghiên cứu cho thấy, chủng nấm mốc Aspergillus fumigatus ET3 với mật số bào tử chủng vào môi trường là 108 bào tử/mL, pH dung dịch khoáng bổ sung là 4 có khả năng sinh tổng hợp phytase cao nhất trên nguồn cơ chất là bột mì sau 2 ngày nuôi ở nhiệt độ môi trường là 35oC.
Từ khóa: Phytase ngoại bào, nấm Aspergillus fumigatus, phytate

Article Details

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