Due to a multitude of industrial applications of keratinolytic proteases, their demands are increasing. The present investigation studied the production and monitoring of the most possible multi-functional applications of YNDH thermoalkaline keratin-degrading enzyme. This work is considered the first that reported YNDH strain closely related to Laceyella sacchari strain; YNDH is a producer of protease/keratinase enzyme and able to degrade natural keratin such as feathers, wool, human hairs, and nails. Experimental design Plackett-Burman (PBD) was applied to evaluate culture conditions affecting the production of thermoalkaline protease/keratinase. Afterwards, Box-Behnken design (BBD) was applied to find out the optimum level of significant variables namely, NH4Cl, yeast extract, and NaNO3 with a predicted activity of 1324.7 U/ml. Accordingly, the following medium composition and parameters were calculated to be optimum (%w/v): NH4Cl, 0.08; feather, 1; yeast extract, 0.04; MgSO4.7H2O, 0.02; NaNO3, 0.016; KH2PO4, 0.01; K2HPO4, 0.01; pH, 8; inoculum size; 5%, cultivation temperature (Temp.) 45 °C and incubation time 48 h. The studied enzyme can degrade keratin-azure, remove proteinaceous materials, and is able to remove hairs from goat hides. These interesting characteristics make this enzyme a good candidate in many applications especially in detergent (Det.), in leather industries, and in pharmaceuticals particularly in nail treatment. The promising properties of the newly keratin-degrading protease enzyme from Laceyella sacchari strain YNDH would underpin its efficient exploitation in several industries to cope with the demands of worldwide enzyme markets.

中文翻译：

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由新的埃及分离株（糖衣藻YNDH）产生的蛋白酶/角蛋白酶的有效多功能生物技术应用。

由于角蛋白水解蛋白酶的许多工业应用，它们的需求正在增加。本研究研究了YNDH热碱性角蛋白降解酶最可能的多功能应用的生产和监控。这项工作被认为是第一个报道与糖酵母菌密切相关的YNDH菌株。YNDH是蛋白酶/角蛋白酶的生产商，能够降解天然角蛋白，例如羽毛，羊毛，人的头发和指甲。实验设计Plackett-Burman（PBD）用于评估影响热碱蛋白酶/角蛋白酶生产的培养条件。然后，采用Box-Behnken设计（BBD）来找出显着变量的最佳水平，即NH4Cl，酵母提取物和NaNO3，其预测活性为1324.7 U / ml。因此，计算出以下最佳培养基组成和参数（％w / v）：NH4Cl，0.08; 羽毛1 酵母提取物，0.04；MgSO4.7H2O，0.02; 硝酸钠，0.016; KH2PO4，0.01；K2HPO4，0.01; pH值8；接种量 5％，培养温度（温度）45°C，孵育时间48 h。所研究的酶可降解角蛋白天蓝色，去除蛋白质物质，并能够去除山羊皮的毛发。这些有趣的特性使该酶成为许多应用中的良好候选者，尤其是在洗涤剂（Det。），皮革工业以及制药（尤其是指甲治疗）中。糖酵母菌YNDH新降解角蛋白的蛋白酶的有前途的特性将支持其在数个行业中的有效开发，以应对全球酶市场的需求。