In the present study, lactose hydrolyzing enzyme β-galactosidase was produced from a novel probiotic Bacillus subtilis SK09 and it was compared with commercially obtained, B. subtilis MTCC 2413. The probiotic Bacilli was initially screened for its ability to hydrolyze the X-gal followed by production of blue colonies. The production medium was formulated using varied nutrients including carbon, nitrogen, mineral salts and amino acid sources. The crude enzyme with an activity of 76.2 U/ml was achieved from our novel strain B. subtilis SK09, and subjected for partial purification by solvent precipitation, dialysis and ion exchange chromatography using DEAE cellulose (DEAE-C) column. Partially purified β-galactosidase enzyme showed 11.6 folds increase in specific activity of 137.02 U/ml. This partially purified enzyme was further characterized and it was observed that it is homogeneous in nature, with molecular weight of 43 kDa. When compared, the β-galactosidase activity of our novel strain was found five times higher than that of commercially obtained strain (27.6 U/ml). Hence, this characteristic of B. subtilis SK09 of increase enzymatic activity can make it a promising candidate for various industrial as well as biotechnological applications.

中文翻译：

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益生菌枯草芽孢杆菌SK09的β-半乳糖苷酶的生产和部分纯化

在本研究中，从新型益生菌枯草芽孢 杆菌SK09生产了乳糖水解酶β-半乳糖苷酶，并将其与商业上获得的枯草芽孢杆菌MTCC 2413进行了比较。首先对益生芽孢杆菌的水解X-gal的能力进行了筛选。通过蓝色殖民地的生产。生产培养基使用多种营养素配制而成，包括碳，氮，矿物质盐和氨基酸。从我们的新型枯草芽孢杆菌获得了活性为76.2 U / ml的粗酶SK09，并使用DEAE纤维素（DEAE-C）柱通过溶剂沉淀，透析和离子交换色谱进行部​​分纯化。部分纯化的β-半乳糖苷酶的比活性为137.02 U / ml，增加了11.6倍。对该部分纯化的酶进行进一步表征，并且观察到其本质上是均质的，分子量为43kDa。当比较时，发现我们新菌株的β-半乳糖苷酶活性比市售菌株（27.6 U / ml）高五倍。因此，枯草芽孢杆菌SK09具有增加的酶活性的这种特性可以使其成为各种工业和生物技术应用的有希望的候选者。