摘要
以1龄大菱鲆(Scophalmusmaximus)为研究材料,研究养殖水温下大菱鲆消化酶的分布及不同温度和不同pH条件下胃、幽门盲囊、前肠、中肠、后肠中蛋白酶、淀粉酶、脂肪酶的活性。确定饵料中主要营养成分的消化部位和主要消化酶的性质。结果表明,各部位蛋白酶活性的最适温度和pH依次为40℃,2 0;40℃,8 0;60℃,8 0;40℃,8 5;60℃,8 0。18℃养殖水温下,在适宜的pH范围内,各部位蛋白酶活力从高到低依次为幽门盲囊、胃、前肠、中肠、后肠;淀粉酶活性的最适温度和pH依次为40℃,6 5;40℃,8 0;40℃,7 5;50℃,7 0;40℃,8 0;淀粉酶活力从高到低依次为幽门盲囊、前肠、中肠、后肠、胃;脂肪酶活性的最适温度和pH依次为40℃,7 5;40℃,6 5;40℃,7 0;40℃,7 5;40℃,7 5;脂肪酶活力从高到低依次为前肠、中肠、幽门盲囊、后肠、胃。
The samples of tubort Scophthalmus maximus were sampled from the turbot breeding base of Yellow Sea Fisheries Research Institute,Chinese Academy of Fisheries Science,in Penglai County.Body weight ranged from 800g to 1000g.The whole digest system was divided into stomach,pylorus,foregut,midgut and hindgut.Protease activity was measured using casein as substrate,1mL of casein (10mg/mL) and 1mL of enzymatic extract were mixed and incubated for 10min under the specific conditions of the experiment (pH,temperature).The reaction was halted by adding 2mL of trichloroacetic acid.After mixture strained,the clear supernatant was measured in the spectrophotometer at 680nm against blanks in which trichloroacetic acid (4% in distilled water) and enzymatic extract were mixed firstly,then casein was added in.Enzymatic extracts were diluted if required.One unit of activity was defined as the amount of enzyme in 1g of wet tissues hydrolytic casein liberated 1μg of tyrosine permin. Amylase activity was measured using soluble starch as substrate,and 0.5mL of soluble starch (20mg/mL) and 0.5mL of enzymatic extract were mixed and incubated for 15min under the specific conditions of the experiment (pH,temperature).The reaction was stopped by adding 1mL of NaOH (2mol/L),then 1mL reagent of DNS was added in.After the mixture was boiled for 5min,cooled quickly.Then 23mL of distilled water was added in,and the clear supernatant was measured on the spectrophotometer at 520nm against blanks in which NaOH and enzymatic extract were mixed,then soluble starch was added in.One unit of activity was defined as the amount of enzyme in 1g of wet tissue which can produce 1mg of maltose in 15min by hydrolyzing soluble starch.Lipase activity was measured using glycerin tributyrate as substrate.The results showed that the optimum temperature and pH in stomach,pylorus,foregut,midgut and hindgut for the protease are 40℃,2.0;40℃,8.0;60℃,8.0;40℃,8.5 and 60℃,8.0; and for the amylase are 40℃,6.5;40℃,8.0;40℃,7.5;50℃,7.0 and 40℃,8.0; and f
出处
《中国水产科学》
CAS
CSCD
北大核心
2005年第1期26-32,共7页
Journal of Fishery Sciences of China
基金
青岛市科技计划项目(02-1-KJ YJ 50).
关键词
大菱鲆
蛋白酶
淀粉酶
脂肪酶
活力
Scophthalmus maximus
protease
amylase
lipase
activity
