一株产碱性纤维素酶放线菌的分离及酶学特性

Separation of an actinomycete producing alkaline cellulase and study on enzymatic characteristics

目的为了弥补目前学术界在产碱性纤维素酶放线菌研究方面的薄弱环节。方法通过实验从采集的土样中,分离获得6株不同菌株,利用CMC透明圈、刚果红染色及酶活测定从中筛选出1株酶活较高的放线菌菌株H,经鉴定,该菌株为间孢囊菌属的一个种（Intrasporangium sp.）;通过液体振荡培养法,对该菌株的发酵条件进行研究,并对该菌株酶系组成及特性进行探讨。结果该菌株为好氧型兼性嗜碱菌,当接种量为6%,pH为8,在28℃条件下振荡培养5 d时生长良好。结论此菌株可产生碱性纤维素酶（CMC酶）,且该酶大部分属内切β-1,4葡聚糖酶,其初始酶活力为2.912 IU/mL。酶反应温度为40℃时,酶活力可达到6-10 IU/mL;当pH为6-11,温度为10-60℃时,酶活力可保持在60%以上,能较好地满足日常洗涤的环境要求。

Aim For the purpose of making up the weakness in actinomycete strain which can produce alkaline cellulose at present.Methods 6 strains of different species were separated from soil samples,from which a actinomycete strain H with high enzyme activities was selected by methods of CMC clear haloes,Congo red dying and cellulase activities detection.It was identified belonging to Intrasporangium.The fermentative conditions,enzyme system constitutions and characteristics of strain H were studied in shaking flask culture.Results Result shows that strain H is a aerobic,amphoteric alkaline actinomycete.The optimal condition for it was 28℃,pH 8 and the inoculation dose was 6% in shaking flask culture for 5 days.Conclusion This strain can produce alkaline cellulase（CMC enzyme）,which was mostly constituted by Cx enzyme.Its original enzyme activities are 2.912U/mL.In the condition of 40℃,its enzyme activities can reach 6～10 U/mL and maintain above 60% at a pH of 6～11,a temperature of 10-60℃.These results could have promising applications in detergents.