中文摘要：

[Objective]This study aimed to illustrate a protease,secreted from a newly isolated Bacillus cereus,and show its potential application in ecofriendly tannery processing. [Method]The skins,such as bovine,ovine,hircine and porcine skins,were treated alone by the protease,which was secreted from a newly isolated Bacillus cereus,for 12 h without sulfide till the hairs were removed entirely. And then the difference of histological appearances treated with and without proteases was analyzed to reveal the dehairing mechanism. [Result]Histological examination of skins dehaired by the crude enzymes revealed that no obvious changes were observed in the dermis. Therefore it may be speculated that the proteases would firstly help in the selective breakdown of keratin tissue in the follicles viz. hydrolyzing the outer epithelial sheath of hair roots of the epidermis,provoking depilation,thereby intact hairs were pulled out without breaking other tissues of the skin. [Conclusion]The protease produced by Bacillus cereus,strain SZ-4 could be in a great measure applied in unhairing in beamhouse of leather making exhibiting considerable unhairing capability without affecting the grain of skins as well as the tensile strength of the leather.

英文摘要：

[Objective] This study aimed to illustrate a protease, secreted from a newly isolated Bacillus cereus, and show its potential application in eeofriendly tannery processing. [Method] The skins, such as bovine, ovine, hircine and porcine skins, were treated alone by the protease, which was secreted from a newly isolated Bacillus cereus, for 12 h without sulfide till the hairs were removed entirely. And then the difference of histological appearances treated with and without proteases was analyzed to reveal the dehairing mechanism. [ Result] Histological examination of skins dehaired by the crude enzymes revealed that no obvious chan- ges were observed in the dennis. Therefore it may be speculated that the proteases would firstly help in the selective breakdown of keratin tissue in the follicles viz. hydrolyzing the outer epithelial sheath of hair roots of the epidermis, provoking depilation, thereby intact hairs were pulled out without breaking other tissues of the skin. [ Conclusion] The protease produced by Bacillus cereus, strain SZ-4 could be in a great measure applied in unhairing in beamhouse of leather making exhibiting considerable unhairing capability without affecting the grain of skins as well as the tensile strength of the leather.