Study of single factor (carbon resource and nitro resource) and orthogonal test discovered that the fermentation medium containing 2% corn powder ,3% bean cake powder and 3% bran is good for neutral proteinase(NPR) production.

• 单因素碳、氮源及正交试验发现以2%25玉米粉、3%25豆粕粉作为碳、氮源并辅以3%25麸皮作为生长因子产酶最好。