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

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 met...

Full description

Bibliographic Details
Main Authors: Muhammad Nadeem, Javed Iqbal Qazi, Shahjahan Baig
Format: Article
Language:English
Published: Instituto de Tecnologia do Paraná (Tecpar) 2010-10-01
Series:Brazilian Archives of Biology and Technology
Subjects:
Online Access:http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132010000500003
Description
Summary: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.
ISSN:1516-8913
1678-4324