局限青霉生淀粉水解酶的产生条件及酶一般性质的研究

RAW STARCH DIGESTION ENZYME FROM PENICILLIUM RESTRICTUM 127-2 AND ITS PROPERTIES

生淀粉水解酶产生菌局限青霉(Penicillium restrictum)127-2是由土壤中分解得到的,具有较强的降解生淀粉能力,水解1g生淀粉需8.0国际单位酶量.Sasaki等曾报道草酸青霉1-9、变幻青霉的培养液能分解生淀粉,但未报道酶的形成条件;Takao等研究了罗尔伏革菌生淀粉酶的形成条件和酶的一般性质.本文介绍局限青霉127-2生淀粉水解酶的形成条件和酶的一般性质.1 材料和方法1.1 菌种培养1.1.1 斜面培养:用查氏琼脂斜面培养基在28—30℃培养5—7天.1.1.2 三角瓶振荡培养:于250ml三角瓶中加40ml发酵培养基,经1kg/cm^2 30分钟灭菌,冷却后接种,置于28—30℃的摇床(200r/min)振荡培养4—5天.1.2

A Penicillium restrictum 127-2 isolated from soil,was a promising producer of raw starch digesting enzyme. The effects of culture conditions and medium components on enzyme formation were investigated. The raw starch digesting enzyme was increased by addition of K2HPO4 0. 83% into the medium containing (g/100ml) soybean cake meal 3, dextrin 2, NH4NO3, 0. 2, MgSO4 · 7H2O 0. 05, the enzyme activity of culture supernatant reached 779u/ml. The optimal pH and temperature range for the enzyme reaction were 4. 0 and 40 C-43℃ respectively. The enzyme was stable in the pH range of 4.0 to 5.0at 40℃15h.