Faculty of Arts and Science, Biology Department, Siirt University, Siirt, Turkey.
Prep Biochem Biotechnol. 2011;41(4):365-81. doi: 10.1080/10826068.2011.552142.
A Bacillus strain was isolated from soil samples from the campus area of Dicle University. Based on 16S ribosomal RNA sequencing, the microorganism was closely related to Bacillus subtilis. Effects of different culture medium, incubation time, carbon and nitrogen sources, and various starches, flours, and chemicals on α-amylase production were examined. Maximum enzyme production (7516 U/mL) was obtained in a basal medium A containing 0.05% Tween 40 in 24 h. Partially purified enzyme showed maximum activity at 60 °C with an optimum pH of 6.0. The effects of 0.2% detergents (sodium dodecyl sulfate [SDS], CHAPS [3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate], and commercial detergent Omo Matic) on partially purified enzyme activity over a period of time (15-150 min) were examined and the order of inhibition effect from the most to the least was found as SDS > Omo Matic > CHAPS. Different metal ions inhibited α-amylase activity at low concentrations (1.5 mM). Co²⁺ was a mild inhibitor and Hg²⁺ and Cd²⁺ were potent inhibitors, whereas Ca²⁺ and Mg²⁺ increased the enzyme activity. At 20 mM, Ca²⁺ enhanced enzyme activity, and different Ca²⁺ concentrations (10-300 mM) were studied.
从迪亚巴克尔大学校园地区的土壤样本中分离出一株芽孢杆菌。基于 16S 核糖体 RNA 测序，该微生物与枯草芽孢杆菌密切相关。研究了不同培养基、培养时间、碳源和氮源以及各种淀粉、面粉和化学物质对α-淀粉酶生产的影响。在含有 0.05%吐温 40 的基础培养基 A 中培养 24 小时，可获得最大酶产量（7516 U/mL）。部分纯化的酶在 60°C 时具有最大活性，最适 pH 值为 6.0。研究了 0.2%清洁剂（十二烷基硫酸钠[SDS]、3-[(3-胆酰胺丙基)二甲氨基]-1-丙磺酸[CHAPS]和商业清洁剂 Omo Matic）对部分纯化酶活性的影响，时间为 15-150 分钟，发现抑制效果的顺序为 SDS > Omo Matic > CHAPS。不同的金属离子在低浓度（1.5 mM）下抑制α-淀粉酶活性。Co²⁺是一种温和的抑制剂，Hg²⁺和 Cd²⁺是有效的抑制剂，而 Ca²⁺和 Mg²⁺则增加了酶的活性。在 20 mM 时，Ca²⁺增强了酶的活性，并研究了不同的 Ca²⁺浓度（10-300 mM）。
