摘要
PS0312菌株是具有特殊生物学特性的青霉菌株。以三角瓶固体培养研究不同条件与菌株产淀粉酶的关系,以及温度与pH值对酶活力的影响。结果表明:PS0312菌株以麸皮30.04%、大豆饼粉3.70%、谷壳3.70%及55.56%蒸馏水组成的培养基固体发酵湿麸曲淀粉酶产量最高。单因子试验结果表明:以培养基pH3、108个/mL的种子液接种量1.85%、培养温度28℃、培养时间96h产淀粉酶量最大。PS0312菌株产淀粉酶在pH2.0～10.0内具较高活性,酶活大小与pH值的关系成双峰形;pH3的条件下酶活性最高,相对酶活100%;pH9的条件下酶活次之,相对酶活84.98%。酶反应最适温度为60℃,90℃条件下相对酶活为39.06%。研究表明:PS0312菌株发酵产淀粉酶是一种在强酸、强碱条件下都具有较高的酶活性和耐高温的特殊的酸性、中温淀粉酶,可在较宽的温度与pH值范围下应用。
The strain PS03 isolated from oil and preserved in our laboratory, which was a special bioactive strain belonging to the family of Penicillium sp., was solid-state cultured in a triangular flask to produce amylase in this work. The effects of medium composition and culture conditions on the production of amylase were examined. PS03 cultured in the medium consisting of 30.04% wheat bran, 3.70% soybean meal powder, 3.70% rise hull and 55.56% distilled water gave the highest amylase production. The optimal culture conditions were determined through single factor experiments to be： initial medium pH 3; the amount of the inoculated seed （containing108 conidia/mL）, 1.85%; culture temperature, 28 ℃; and culture time, 96 h. In addition, the crude enzyme solution obtained under the above conditions was sampled to determine optimal pH and temperature for the reaction of this enzyme. The amylase from PS03 showed high activity in a pH range between 2.0 and 10.0. The relationship between enzyme activity and pH was a double peak-shaped curve. The highest peak of enzyme activity was observed at pH 3, with 100% relative activity, and the peak of enzyme activity appearing at pH 9 was lower, indicating a relative activity of 84.98%. The optimal reaction temperature of this enzyme was 60 ℃, and the relative activity at 90 ℃ was 39.06%. It can be concluded through this study that the amylase produced by PS03 is a special acidic middle-temperature amylase having good tolerance to strong alkaline and acidic conditions as well as high temperature.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2010年第23期294-299,共6页
Food Science
