Mokoba Matthews, Gessesse Amare
Department of Biological Sciences and Biotechnology, School of Life Sciences, Botswana International University of Science and Technology, Palapye, Botswana.
Appl Biochem Biotechnol. 2025 May 27. doi: 10.1007/s12010-025-05280-7.
Annually, the poultry industry releases millions of tons of feather waste into the environment. With a protein content of 91%, feather offers huge potential to serve as an animal feed supplement. However, keratin, the main protein component of feather, is highly resistant to hydrolysis by animal and plant proteases. The use of physicochemical methods to hydrolyze feather, in addition to being expensive, causes decomposition of some amino acids. Thus, microbial bioconversion of feather offers an attractive option for the production of useful products. In this study, an alkaliphilic feather-degrading strain, Bacillus pseudofirmus BCC026, was isolated from the Makgadikgadi salt pan in Botswana. When grown in liquid culture containing feather as the sole source of nitrogen, it resulted in complete solubilization within 48 to 72 h. The organism also produced an alkaline protease, soluble proteins, and peptides/amino acids into the culture medium. The enzyme showed optimum activity in the pH range of 7.5-10.5 and at 70 °C. It was also active and stable in commercial detergents and resulted in complete removal of stain from cotton fabrics. The enzyme was also effective in removing hair from goatskin, indicating its potential for dehairing application. Microbial growth substrates are known to account for a significant proportion of the production cost of industrial enzymes. Since protease BCC026 was produced using feather, a cheap and readily available resource, enzyme production cost could be significantly reduced. Moreover, after enzyme recovery, the soluble proteins and peptides/amino acids in the filtrate could be used for different applications.
家禽业每年向环境中排放数百万吨羽毛废弃物。羽毛的蛋白质含量为91%，作为动物饲料补充剂具有巨大潜力。然而，羽毛的主要蛋白质成分角蛋白对动植物蛋白酶的水解具有高度抗性。使用物理化学方法水解羽毛，除了成本高昂外，还会导致一些氨基酸分解。因此，羽毛的微生物生物转化为有用产品的生产提供了一个有吸引力的选择。在本研究中，从博茨瓦纳的马卡迪卡迪盐沼中分离出一株嗜碱羽毛降解菌株——假芽孢杆菌BCC026。当在以羽毛作为唯一氮源的液体培养基中生长时，它能在48至72小时内完全溶解。该菌株还向培养基中分泌了一种碱性蛋白酶、可溶性蛋白质以及肽/氨基酸。该酶在pH值7.5 - 10.5范围内以及70°C时表现出最佳活性。它在商用洗涤剂中也具有活性且稳定，能完全去除棉织物上的污渍。该酶在去除山羊皮上的毛发方面也很有效，表明其在脱毛应用方面的潜力。已知微生物生长底物占工业酶生产成本的很大一部分。由于蛋白酶BCC026是利用羽毛生产的，羽毛是一种廉价且容易获得的资源，因此酶的生产成本可以显著降低。此外，酶回收后，滤液中的可溶性蛋白质和肽/氨基酸可用于不同用途。
