Abstract:The aim was to screen a cold-active elastase producing strain and study the enzymatic properties in order to establish the theoretical basis for its application of meat tenderization.One strain,named XZE116,which produced cold-active elastase was screened using elastin as sole nitrogen source on elastin agar plate according to the ratio of the diameter of the hydrolytic circle to the diameter of the colony.The strain was identified as Bacillus brevis by morphological,physiological,biochemical tests and 16S rDNA gene sequence analysis.The enzyme was highly active over a wide range of pH from 7.0 to 12.0,with an optimum at pH 8.0.It exhibited maximal activity at 25 ℃ and was stable within two hours below 40 ℃.The enzyme activity was activated by Mg2+,but was strongly inhibited by Hg2+ and Pb2+.Its activity was completely inhibited by phenylmethanesulfonyl fluoride(PMSF),but not by E-64,suggesting that the enzyme is a serine-protease.The elastase activity was slightly reduced by anionic(0.1% SDS),cationic(0.1% cetyltriethylammnonium bromide,CTAB),non-ionic surfactants(1% Tween-80 and 1% Triton X-100).Considering its promising properties,the elastase from Bacillus brevis XZE116 may find potential application in meat industry.
