产酸性蛋白酶深红沙雷氏菌的筛选及其在种子萌发中的应用

Screening of Acidic Protease Producing Strains and Its Application in Seed Germination

酸性蛋白酶在工业生产中需求量巨大,但我国产酸性蛋白酶菌株的品种较为单一,因此,亟需开发新型的微生物源蛋白酶和选育高产蛋白酶菌种。从海口红树林土壤中筛选出一株可以在酸性环境下产蛋白酶的菌株,采用福林酚法测定蛋白酶活,经过形态学观察、生理生化实验及16S rRNA序列比对鉴定为深红沙雷氏菌。利用该菌株发酵鱼下脚料制备生物液肥,通过种子萌发实验,研究发酵液的促生效果。结果显示,分离出的产酸性蛋白酶菌株R3可以用于鱼下脚料的发酵,在发酵液稀释5~25倍时,处理60 h均可以促进菜心种子的萌发,与市场购买的液肥效果相同。利用分离出的产酸性蛋白酶菌株发酵鱼下脚料制备生物液肥,实现了对废弃鱼蛋白资源的重新利用,增加了鱼类产品的附加值。

Acid protease is of great demand in industrial production. At present,the varieties of acidic protease producing strains in China are relatively rare,so it is urgently needed to develop new microbial protease and select high-yield protease strains. A strain producing protease in acidic environment was screened from mangrove soil in Haikou. The protease activity was determined by folinol method. It was identified as Serratia rubidaea by morphological observation,physiological and biochemical experiment and 16S rRNA sequence blast. The strain was used to ferment fish waste to produce biological liquid fertilizer. The effect of the fermentation liquid as biological liquid fertilizer was evaluated through seed germination promotion experiment. The results showed that the protease producing strain R3 isolated in this study could be used for the fermentation of fish waste. When the fermentation broth was diluted 5 to 25 times,the treatment for 60 h could promote the germination of cabbage seeds,and the germination rate reached the effect of liquid fertilizer. In this study,the isolated strain producing acid protease was used to ferment fish waste to biological liquid fertilizer,which utilized the waste fish protein as the resources and increased the value of fish products.