Enhanced production of alkaline protease by a mutant of Bacillus licheniformis N-2 for dehairing

Brazilian Archives of Biology and Technology

Muhammad Nadeem²  Javed Iqbal Qazi¹  Shahjahan Baig² 

[1] ,PCSIR Laboratories Complex Biotechnology and Food Research Center Lahore,Pakistan

关键词: Bacillus mutants;    mutagenic treatments;    alkaline protease;    dehairing agent;   

DOI  :  10.1590/S1516-89132010000500003

来源: SciELO

【 摘 要 】

The purpose of the present investigations was to improve the yield of alkaline protease for leather dehairing by subjecting the indigenous proteolytic strain Bacillus licheniformis N-2 to various mutagenic treatments viz. UV irradiations, NTG (N-methyl-N-nitro-N-nitrosoguinidine) and MMS (methyl methane sulfonate). After screening on skim milk agar plates, a total of nine positive mutants were selected for shake flask experiments. Among these, the best proteolytic mutant designated as UV-9 showed 1.4 fold higher alkaline protease activity in preoptimized growth medium than the parent strain. The fermentation profile and kinetic parameters such u(h-1), Yp/s, Yp/x, Yx/s, q s, Qs, q p and Qp also indicated the superiority of the selected mutant UV-9 for alkaline protease production over the parent strain and rest of the mutants. The dehairing capability of mutant UV-9 alkaline protease was analyzed by soaking goat skin pieces for different time intervals (3-15 h) at 40 º C. A complete dehairing without degradation of collagen was achieved after 12 h, indicating its commercial exploitation in leather industry.

【 授权许可】

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