摘要
试验以半透膜法收集地衣芽孢杆菌（Bacillus licheniformis）De株的胞外产物（extracellular products,ECP）,以匀浆离心法提取凡纳滨对虾（Litopenaeus van-namei）成虾的肝胰腺和肠道消化酶,将芽孢杆菌胞外产物和对虾消化酶按体积比10∶90混合,采用体外分析法研究在不同温度、pH及胞外产物添加量等条件下胞外产物对对虾淀粉酶活性的影响.试验共设A、B、C、D、E 5个试验组,每组三个平行.其中空白组A为地衣芽孢杆菌的胞外产物,试验组B、C组分别为添加了胞外产物的对虾肝胰腺消化酶、肠道消化酶,对照组D、E分别为未添加胞外产物的对虾肝胰腺消化酶和肠道消化酶样品.温度为20～40℃时试验组B、C的淀粉酶活性要明显高于对照组（p〈0.05）,其中肝胰腺淀粉酶和肠道淀粉酶的活性分别提高了25.9%和19.3%,但该温度要远低于芽孢杆菌胞外淀粉酶的最适温度60～90℃.在pH为5～6时,试验组B、C的淀粉酶活性明显高于对照组（p〈0.05）,对虾肝胰腺淀粉酶和肠道淀粉酶的活性分别较对照组提高了33.3%和122.2%,而该pH同样要低于芽孢杆菌胞外淀粉酶的最适pH值（6～9）.此外,研究还表明试验组的淀粉酶活性随胞外产物添加量的升高而降低,即胞外产物在一定条件下可能抑制对虾内源淀粉酶的生物学活性.从本研究看,地衣芽孢杆菌胞外产物在一定程度上可促进对虾的淀粉酶活性,而当胞外产物活性高于0.02 U/mg蛋白质时,对虾淀粉酶活性将受到抑制.
The interaction between extracellular products（ECP） of Bacillus licheniformis strain De and amylase of white shrimp（Litopenaeus vannamei） was studied in vitro.The ECP were collected by semiperable membrane method,and the digestive enzyme of white shrimp hepatopanceas and intestine were collected by homogenate and centrifugation.The effects of ECP on amylase activity of white shrimp were investigated at different temperature,pH and ECP concentration.There were 5 test groups（A,B,C,D,E） in this experiment,the digestive enzyme of group A was ECP,groups B and C were hepatopanceas and intestinal digestive enzyme of shrimp supplemented with ECP,groups D and E were control groups of B and C,which enzyme without ECP.The results indicated that amylase activity of enzyme of test groups B and C（ECP were added） were significantly higher than（p〈0.05） that of the control groups D and E at 20～40℃,which temperature was much lower than the optimum temperature for amylase activity of ECP（60～90℃）,comparatively,the hepatopanceas and intestinal amylase activity of white shrimp increased 25.9% and 19.3%,respectively.The amylase activity of test groups B and C were significantly higher（p〈0.05） than that of control groups at the optimum pH（5～6）,under the optimum pH amylase
activity of hepatopanceas and intestine increased 33.3% and 122.2% compared with that of control groups,but the optimum pH for the amylase of group A was 6～9,it was higher than the optimum pH（5～6）.Moreover,the results also showed that the amylase activity of test groups（ECP were added） decreased with increasing of the quantity of ECP,which implied ECP of Bacillus licheniformis,maybe,was a kind of inhibitor for white shrimp endogenetic amylase in the certain condition.In conclusion,ECP of Bacillus licheniformis could improve amylase activities of white shrimp in vitro in a certain extent,if ECP amylase exceeded 0.02U/mg protein the activity of white shrimp endogenetic amylase would be decreased.
出处
《台湾海峡》
CAS
CSCD
北大核心
2007年第4期536-542,共7页
Journal of Oceanography In Taiwan Strait
基金
国家"十五"攻关项目(2004BA526B0202)
广东省重大科技专项项目(A3050304)
广东省重大科技兴渔项目(B200201A01)
关键词
地衣芽孢杆菌
胞外产物
凡纳滨对虾
淀粉酶
体外
Bacillus licheniformis
extracellular products
Litopenaeus vannamei
amylase
in vitro
