conclusions: the obtained results prove that keratinolytic potential of both tested bacterial strains could be applied mainly in biodegradation of feathers, however, b. cereus and b. polymyxa differed in terms of keratinase and protease production on each of the substrates. biodegradation of highly resilient structures like hair or pig bristle requires further analysis of process conditions. re...

Keratinase is a potential industrial enzyme for handling keratinaceous solid wastes and also cleaner dehairing alternative to chemical methods in tanneries. The technologies towards circular economy approach are gaining importance leather manufacturing sector. In this study, new bacterial strain Bacillus sp. KLP1, exhibiting high tolerance sodium chloride sulphide, was isolated. This effectivel...

Keratinase is a protease which degrades the insoluble protein keratin that largely found in feather waste. Fifty-seven soil samples were collected from and poultry waste dumping sites. All these subjected for enrichment Whole meal medium containing 1% chicken as sole source of Carbon, nitrogen energy with pH 8.0 incubated at 30°C on shaker condition (150 rpm) 7 days. Out 57 flasks only 21 sh...

Feather waste is generated in large amounts as a by-product of commercial poultry processing. This residue is almost pure keratin, which is not easily degradable by common proteolytic enzymes. Eight strains of Bacillus, isolated from decomposing feathers were tested for the hydrolysis of feather wastes in the laboratory. Among these strains, Bacillus cereus KB043 was the best feather degrading ...

The keratinase (kerA) gene from Bacillus licheniformis PWD-1 was expressed and purified in insect cells. First, the sequence encoding Ker-His-Flag was designed based on the amino acid sequence of the protein and peptide and codon optimization in order to ensure the high expression in insect cells. In the next step, the synthetic DNA was inserted into the pUC57 vector and then sub-cloned in the ...

Keratins are tough, fibrous proteins found as the major protein component in hair. Chemical hair removal is harsh and results severe toxicity pollution, hence, a need for non-chemical enzymatic process. The aim of this study to characterise keratinase from isolated keratin-degrading Bacillus licheniformis-K51, subtilis-K50 sp.-K53 investigate its potential removal. collagenolytic ability kerati...

In black feathers, melanin is embedded in keratin matrix that makes feather more resistance to the microbial degradation. Chryseobacterium sp. RBT previously isolated from the poultry waste disposable site revealed strong sulfitolytic and keratinolytic activities. Maximum keratinase activity was observed at 48 h (89.12 U ml-1) showed 83 % of native black feather degradation. The concentration o...

A wild type Streptomyces strain BA7 which was isolated from soil, showed a high keratinolytic activity when cultured on native feather medium. Optimum keratinolytic activity was observed at 50 oC and pH 8.5 when using fluid supernatant obtained from aerated culture of this organism. The keratinolytic activity was completely stable (100%) between 30 and 60 oC. The molecular weight of crude enzym...