普通卷甲虫肠道可培养细菌的分离、鉴定及产消化酶活性

目的分离培养普通卷甲虫肠道中的可培养细菌,筛选有产消化酶活性的细菌,推测其在协助普通卷甲虫消化食物中的作用。方法通过传统分离培养法分离普通卷甲虫肠道中的可培养细菌,利用平板透明圈法筛选产淀粉酶、蛋白酶、纤维素酶和脂肪酶活性的细菌,利用水解圈与菌落直径的比值,比较不同细菌的产消化酶活性。利用SPSS 20.0软件进行统计学分析,组间比较采用单因素方差分析。结果在普通卷甲虫肠道中分离出4个属9种细菌,其中气单胞菌属3种,假芽胞杆菌属和柠檬酸杆菌属各2种,芽胞杆菌属和假单胞菌属各1种。9种细菌中弗氏柠檬酸杆菌、豚鼠气单胞菌、南海假芽胞杆菌等3种细菌可产蛋白酶,嗜水气单胞菌、波特卡伦柠檬酸杆菌、水生气单胞菌、豚鼠气单胞菌和南海假芽胞杆菌等5种细菌可产纤维素酶,嗜水气单胞菌、波特卡伦柠檬酸杆菌、印度芽胞杆菌、水生气单胞菌、嗜盐假芽胞杆菌、豚鼠气单胞菌和南海假芽胞杆菌等7种细菌可产淀粉酶,未筛选到产脂肪酶细菌。统计学分析表明,3种产蛋白酶细菌和5种产纤维素酶细菌的产酶活性差异无统计学意义。而7种产淀粉酶细菌产酶的活力间差异有统计学意义,水生气单胞菌的产淀粉酶活性能力最强。结论普通卷甲虫肠道可培养细菌结构简单,但有消化酶活性的细菌种类多,5种细菌有产2种以上消化酶功能,说明肠道细菌可能在普通卷甲虫食物消化中起着重要作用。

The digestive enzyme activities of culturable bacteria isolated from intestine of pill bug, Armadillidium vulgare

Objective To isolate and culture the bacteria from the intestine of Armadillidium vulgare, screen the strains with digestive enzyme activity, and speculate its role in assisting A. vulgare′s digestion of food. Methods The culturable non-anaerobic bacteria were isolated from A. vulgare intestines with traditional isolation and culture method. The digestive enzymes of different bacteria were compared using the ratio of hydrolysis circle(D) to colony diameter(d)(D/d). Statistical software SPSS 22.0 independent sample t test was used for the comparison. Results Nine bacteria belonging to four genera were isolated, including 3 species belonging to Aeromonas, 2 species each belonging to pseudobacillus and Citrobacter respectively, and 1 species each belonging to Bacillus and Pseudomonas respectively. Among them, C. portucalensis, A.caviae and F. nanhaiensiscan were able to produce protease, A. hydrophila, C. portucalensis, A. aquatica, A. caviae and F. nanhaiensis were able to produce cellulase, while A. hydrophila, C. portucalensis, B. indicus, A. aquatica, F. shalophilus, A.caviae and F.nanhaiensis were able to produce amylase. Lipase producing bacteria were not found. Statistical analysis showed that there were no significant differences in enzyme activity among 3 protease-producing bacteria and 5 cellulase-producing bacteria. There were significant differences among the 7 amylase-producing bacteria. A. hydrophila had the strongest amylase-producing ability. Conclusion The structure of culturable bacteria in the intestine of A. vulgare is simple, but there are many kinds of bacteria with digestive enzyme producing activity. 5 kinds of bacteria can produce more than two kinds of digestive enzymes, indicating that intestinal bacteria of A. vulgare may play an important role in food digestion.