Strain capable of degrading feather keratin efficiently and screening method thereof

Abstract

The invention relates to a strain capable of degrading feather keratin efficiently and a screening method thereof. According to result of the analysis and identification of the sequence of 16SrDNA and the result of the identification of a Biolog system, F4 is determined to be Bacillus licheniformis and is named Bacillus licheniformis F4. The Bacillus licheniformis F4 was collected in China Center for Type Culture Collection with a collection number of CGMCC No.4229 on October 22th, 2010. The screening method comprises: primarily screening, separating, enriching, and secondarily screening to obtain the strain capable of degrading feather keratin efficiently. In the invention, the strain capable of degrading feather keratin efficiently is obtained by two steps of screenings under strict conditions, wherein primary screening conditions are a carbon source and a nitrogen source, and secondary screening conditions are complete degradation of feathers and measurement of enzymatic activity of keratin. The strain is inoculated into a fermentation culture medium containing complete feathers to perform fermentation culture for 60 hours, all barbules of the feathers are removed, the left feather stems and a major part of removed pinnules are degraded, and the feather removing and feather keratin degrading effects of the strain are obvious.

Description

technical field [0001] The invention relates to the field of bioengineering, and relates to the screening of microbial strains, in particular to a bacterial strain for efficiently degrading feather keratin and a screening method thereof. Background technique [0002] Large-scale livestock and poultry farming produces a large amount of livestock and poultry waste, among which feather waste is the most, and its output is huge, reaching several million tons globally every year. Poultry feathers are mainly composed of keratin. Keratin is a hard protein with strong resistance and refractory degradation. It has high structural stability and its strength is equivalent to that of nylon. Keratin is insoluble under normal conditions and cannot It is degraded by proteases such as pepsin and trypsin, and has long polymer chains that are resistant to specific protease activity. [0003] Feather meal can be obtained through biotransformation. Feather meal can be added to feed instead of ...

AI Technical Summary

Problems solved by technology

At present, domestic research on microbial degradation of keratin mainly focuses on the separation of strains and the extraction and purification of enzymes. Although some progress has been made, none of them can achieve industrial production and cannot meet the needs of the industry for its degradation. Most microorganisms degrade feathers. Certain pre-treatment is still required, so it is necessary to further isolate excellent feather keratin-degrading strains

Images