角蛋白酶降解菌分离筛选及其脱毛能力研究

Isolation,Screening and Characterization of Wool Keratin Degrading Bacteria

为获得可高效用于羊毛角蛋白降解的菌株,对5个不同省份的鸡圈、羊圈和牛圈的土壤进行取样,并从中筛选获得一株拥有角蛋白降解能力的菌株。通过对菌株进行分类鉴定,可确定其为肠杆菌。对其中角蛋白酶的酶学性质进行分析,在摇瓶发酵中,37℃培养36 h时,获得最佳的角蛋白酶活力为8.23 U/mL,该酶在温度为60℃,pH=10时具有较好的活力,但是在温度为30~60℃,pH 6~10范围内均有较好的稳定性;将该酶用于制革脱毛,该酶在4 h内可以将大部分毛发脱除,在浸灰24 h后,可以完全脱除毛发,且能保持粒面完整。综上所述,角蛋白酶在羊毛降解及羊皮脱毛中有较大的应用潜力。

In order to obtain high efficient strains for degradation of wool keratin,soil samples from chicken pen,sheep pen and cattle pen in five different provinces were collected and enriched.A strain,which had obviously degradation ability to keratin,was screened and analyzed.By analyzing the strain,it was identified as Enterobacter.In order to further explore the enzymatic properties of keratinase,the optimum keratinase activity was 8.23 U/ml at 37℃for 36 h with shake flask fermentation.The optimum conditions for the keratinase are with 60℃and pH=10,and it has well stability in the range of 30~60℃and pH 6~10,which are consistent with the conditions in beam-house process.Using it for unhairing,it found that most of hairs had been removed in 4 h as well as some short hairs were residual.After 24 h in liming,all of hairs could be successfully removed and there was no obviously damage on the grain surface.In conclusion,keratinase has great potential in unhairing process.