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目的:通过改变酶的反应温度和pH,离体分析白斑狗鱼体内淀粉酶、蛋白酶和脂肪酶活性变化.方法:分别采用Folin酚法、DNS法和氢氧化钠滴定法测定蛋白酶、淀粉酶和脂肪酶活性.结果:在白斑狗鱼肝胰脏、胃二部位,淀粉酶的最适温度均为30℃,肠道淀粉酶的最适温度为40℃;最适pH值分别为4.0、2.0、7.0.肝胰脏、胃二部位脂肪酶的最适温度均为40℃,肠道脂肪晦的最适温度为50℃;最适pH值分别为5.0,4.0、5.0.肝胰脏、胃、肠道蛋白酶的最适温度均为50℃;最适pH值分别3.0、3.0、9.0.结论:在各自最适温度下,脂肪酶、淀粉酶、蛋白酶比活力均为:肠道>胃>肝胰脏. 相似文献
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采用动物性饵料和人工饲料培育1~10日龄怀头鲇(Silurus soldatovi)仔稚鱼,分析测定了全鱼酸性、碱性蛋白酶、淀粉酶、脂肪酶以及碱性磷酸酶的活性。结果表明:孵化后3天开口期仔鱼已具有较高的碱性蛋白酶活性,5日龄时碱性蛋白酶比活力达到较高值,8日龄时出现低值,总体变化呈波动上升趋势;酸性蛋白酶活性在1~8日龄处于较低水平,8日龄后开始迅速升高;淀粉酶活性在5日龄左右达到最高值,随后酶活性开始下降至较低水平;脂肪酶活性变化波动较大,表现为双峰型,两个峰值分别出现在3~4日龄和6~8日龄。摄食动物性饵料仔稚鱼消化酶活性和碱性磷酸酶活性均高于摄食人工饲料。在整个早期发育过程中,碱性蛋白酶比酸性蛋白酶活性高,碱性蛋白酶、淀粉酶比活力在约8日龄仔稚鱼转变期明显下降,而酸性蛋白酶活性开始迅速升高,这说明消化酶活性的变化与仔稚鱼发育过程中消化机能转换具有相关性。怀头鲇在10日龄内碱性磷酸酶活性呈上升趋势,表明怀头鲇胃肠道功能的逐步发育完善。 相似文献
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额尔齐斯河野生丁(鐬)蛋白酶、淀粉酶活性的研究 总被引:1,自引:0,他引:1
目的:研究温度、pH、金属离子对新疆额尔齐斯河野生丁(鐬)消化道蛋白酶、淀粉酶活性的影响.方法:酶学和生化法.结果:丁(鐬)蛋白酶活性,后肠>前肠>中肠>肝胰脏;淀粉酶活性,后肠>中肠>前肠>肝胰脏.肠道、肝胰脏蛋白酶的最适温度分别为35℃、40℃,淀粉酶的最适温度均为40℃.消化道各部位蛋白酶、淀粉酶的体外最适pH为7.5.在试验的离子浓度范围,高浓度Ag 、Cu2 抑制酶活力;高浓度Fe3 、Mg2 、Ca2 促进酶活力;Pb 、Ba2 对消化道酶活力影响依浓度和部位而变.结论:消化酶最适温度均高于所处环境温度,最适pH值变化范围偏碱性;不同浓度金属离子对丁(鐬)消化道各部位蛋白酶、淀粉酶活力高低表现出不同的变化趋势. 相似文献
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温度和pH对洞庭鲇鱼消化酶活性的影响 总被引:3,自引:0,他引:3
采用酶学分析方法研究了温度和pH对洞庭鲇鱼蛋白酶、脂肪酶和淀粉酶活力的影响。结果表明,在设定的温度和pH范围内,鲇鱼各消化酶的活力均随着温度和pH的升高呈现先升后降的变化趋势。其中,胃蛋白酶的最适温度为40℃,肝胰脏、前肠、中肠和后肠蛋白酶的最适温度为45℃;脂肪酶的最适温度均为35℃;胃淀粉酶的最适温度为35℃,其他部位均为30℃。胃、肝胰脏、前肠、中肠和后肠蛋白酶的适宜pH分别为2.0、8.5、7.5、8.0和8.0;脂肪酶的适宜pH均为7.5;淀粉酶肝胰脏的适宜pH为7.5,其余部位均为7.0。鲇鱼各消化酶活力存在器官特异性。在最适温度下,蛋白酶活力顺序为前肠>肝胰脏>胃>中肠>后肠,脂肪酶的活力顺序均为肝胰脏>胃>前肠>中肠>后肠,淀粉酶的活力顺序为肝胰脏>前肠>中肠>后肠>胃,各部位之间差异显著(P<0.05)。 相似文献
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温度对兰州鲇消化酶活性的影响 总被引:12,自引:0,他引:12
测定了兰州鲇(Silurus lanzhouensis)胃、肝胰脏、前肠、中肠、后肠在不同温度(15℃、20℃、25℃、30℃、37℃4、2℃、47℃)条件下的蛋白酶、淀粉酶和脂肪酶的活性。结果表明,随温度的升高,各种酶活性的变化均表现为先增高后下降直至不能检出。消化道各部位蛋白酶的最适温度均为42℃;淀粉酶的最适温度除胃和肝胰脏为37℃外,其他部位均为30℃;脂肪酶的最适温度除后肠为30℃外,其他部位均为25℃。消化酶的最适温度高于其生活水域的水温,反映出消化酶作为酶蛋白的耐热性。最适温度下,蛋白酶活性前肠≈中肠>后肠>肝胰脏≈胃;淀粉酶活性前肠>中肠>肝胰脏>胃>后肠;脂肪酶活性中肠>后肠>前肠≈肝胰脏>胃。研究结果还表明,前肠和中肠是兰州鲇消化蛋白的主要部位,中肠是其消化脂肪的主要部位,而前肠是其消化淀粉的主要部位。在消化酶表现出活性的温度范围内,蛋白酶活性明显高于淀粉酶活性。实验还表明脂肪酶具有活性的温度范围较蛋白酶和淀粉酶窄。 相似文献
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目的:从青藏高原冰川雪中筛选出一菌多酶的菌株.方法:对恢复出的4个细菌,通过平板透明法研究其产淀粉酶、脂肪酶和蛋白酶的特性.结果:LHG-C-9为惟一可以产淀粉酶的菌株,所产脂肪酶活性最高.4个菌株均不产蛋白酶.结论:LHG-C-9最适生长温度为15℃,属于耐冷菌.对该菌所产淀粉酶和脂肪酶的性质进行了初步研究,其随产淀粉酶的最适作用温度为50℃;最佳产酶pH值为7.0,该pH值所产酶活为83.9U/mL;在60℃的高温下温浴10min后酶活为0%.该菌株所产脂肪酶的最适作用温度为20℃;最佳产酶pH值为7.0,该pH值所产酶活为9.2U/mL;50℃温浴1h后酶活力不足34%. 相似文献
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牛蛙主要消化酶的分布及pH和温度对消化酶活力的影响 总被引:2,自引:0,他引:2
研究了牛蛙消化系统蛋白酶、脂肪酶、淀粉酶和纤维素酶的分布情况以及pH和温度对这些消化酶活力的影响.结果表明:在各自生理pH值下,牛蛙消化系统不同部位蛋白酶活力大小顺序依次为胰脏>胃>中肠>食道>前肠>后肠,胃、肠和胰脏蛋白酶的最适pH值分别为2.2、7.4和9.6,最适温度分别为45℃、50℃和45℃.脂肪酶活力大小顺序依次为胰脏>后肠>中肠>前肠>胃>食道,胃、肠和胰脏脂肪酶的最适pH值分别为2.2、7.4和8.0,最适温度均为50℃.淀粉酶活力大小顺序依次为胰脏>中肠>后肠>前肠>胃>食道,胃、肠道和胰脏淀粉酶的最适pH分别为7.0、8.0和9.6,最适温度均为35℃.在牛蛙消化系统未检测到明显纤维素酶活力. 相似文献
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红螯螯虾胚胎发育期主要消化酶和同工酶的活性变化 总被引:1,自引:0,他引:1
采用生物化学方法测定了红螯螯虾(Cherax quadricarinatus)胚胎发育各期主要消化酶(胃蛋白酶、胰蛋白酶、淀粉酶、纤维素酶和脂肪酶)的比活力及主要同工酶(乳酸脱氢酶、苹果酸脱氢酶、葡萄糖-6-磷酸脱氢酶和酯酶)的活力。结果显示,5种消化酶各自表现出不同的变化模式,胃蛋白酶和胰蛋白酶的比活力早期均逐渐上升,到发育后期胃蛋白酶出现快速下降,而胰蛋白酶却仍保持较高水平;淀粉酶比活力呈“V”字型变化趋势,晚期活性较高;纤维素酶和脂肪酶的比活力则均较低。4种同工酶酶谱随胚胎的发育渐趋复杂,酶活性也随之增强。结果表明,消化酶和同工酶活力的高低均受其基因的调控,并随胚胎发育适时表达,为胚胎组织、器官和系统的形成以及未来仔虾的开口摄食提供物质保证。 相似文献
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The role of the adipokinetic hormone (AKH) in the control of protease, amylase and lipase activities is examined using the cockroach Periplaneta americana and the fruit fly Drosophila melanogaster as model species. The effects of Peram‐CAH‐I and ‐II on the activity of cockroach digestive enzymes in the gastric caeca and midgut are measured both in vivo and in vitro. The results show the activity of proteases, amylases and lipases in both parts of the gut: amylase activity is higher in the gastric caeca than in the midgut; lipase activity presents the opposite trend; and protease activity is similar in both organs. The applied hormones stimulate the activity of all digestive enzymes, although this stimulation is not uniform; AKHs affect enzymes selectively, and in some cases unequally, in the gastric caeca and midgut. No substantial differences between Peram‐CAH‐I and ‐II stimulation are recorded. The in vitro results demonstrate that AKH stimulates digestive enzyme activity directly. In agreement with the cockroach results, enzymatic activity in D. melanogaster larvae producing nonfunctional AKH is lower than that in the larvae with ectopically expressed Akh gene, where enzyme activity reaches or even exceeds that of the controls. Overall, the results demonstrate the active role of AKHs in the stimulation of digestive enzyme activity in insects. 相似文献
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杠柳杀虫组分F3-28对东方粘虫和小地老虎幼虫中肠消化酶活性的影响 总被引:1,自引:1,他引:0
F3-28是从杀虫植物杠柳Periploca sepium Bunge根皮中分离的一个具有杀虫活性的馏分,其主要成分为杠柳苷A、杠柳苷E和杠柳苷X。为了探索F3-28的初始作用部位, 为深入研究其作用机理奠定基础, 本研究采用经典的昆虫消化酶活性测定方法, 比较了F3-28对小地老虎Agrotis ypsilon和东方粘虫Mythimna separata 5龄幼虫消化酶系活性的影响。结果表明:对F3-28不敏感的小地老虎幼虫摄食F3-28后,其中肠蛋白酶、淀粉酶、脂肪酶的活性无显著变化。对F3-28敏感的东方粘虫幼虫摄食F3-28后2,4,8,10,12,24,48 h, 其中肠总蛋白酶活性分别为对照组的0.76,2.53,1.45,1.88,1.54,1.46,1.70倍,且和药物浓度呈依赖关系; 类胰蛋白酶的活性分别为对照组的1.60, 1.75,1.60,1.12,1.39,1.16,1.15倍(以BAPNA为底物)或1.68,1.95,1.53,1.26,1.15,1.13,1.14倍(以TAME为底物),且和药物浓度呈依赖关系; 类胰凝乳蛋白酶活性分别为对照组的0.50,1.66,1.44,1.18,1.54,1.08和1.03 倍,但和药物浓度无依赖关系; 淀粉酶的活性分别为对照组的1.60,1.35,1.27,1.31,1.23和1.20 倍,但和药物浓度无依赖关系;对脂肪酶活性无明显影响。这些结果说明,杠柳杀虫活性组分F3-28的作用机理可能涉及对试虫中肠蛋白酶的激活,特别是对类胰蛋白酶的激活。 相似文献
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Abstract. .Reproducing females of the firebug, Pyrrhocoris apterus (Linnaeus) (Heteroptera: Pyrrhocoridae), reared under long-day (LD 18:6h) photocycle (long-day females), and diapausing females reared under short-day (LD 12:12h) conditions (short-day females) were analysed for temporal patterns of feeding, drinking and gut digestive enzyme activities. In long-day females the highest activities of feeding and drinking were found at the beginning of each reproductive cycle. Significant correlation between feeding and drinking activities in both reproducing long-day females and short-day females during pre-diapause state was found. In pre-diapausing short-day females the cyclical pattern of feeding and drinking was maintained despite the inhibition of reproduction. After entering the diapause their feeding activity became very low. Analysis of five gut enzymes revealed that short-day females differ significantly from long-day females in higher protease, amylase and esterase activities, in case of lipase only at certain times of their adult life; no significant difference was found in the aminopeptidase activity. Positive correlations between intensity of feeding and gut enzyme activities were observed in short-day females. Using several protease inhibitors most protease activity in the gut of P.apterus was identified as cysteine and aspartyl proteases, and only a small part of the activity could be caused by some serine proteases. 相似文献
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Protease activities in the secreted saliva, salivary glands and midgut of the green mirid, Creontiades dilutus, were investigated. The saliva and salivary glands had more protease activity than the midgut, but no differences in protease activity levels were detected between male and female mirids, adult mirids and third instar nymphs, or between fed and starved mirids.In the salivary glands, chymotrypsin-like serine proteases predominated, as characterised by inhibitor specificity, basic pH optima, and hydrolysis of N-benzoyl-L-tyrosine p-nitroanilide and N-succinyl-ala-ala-pro-leu p-nitroanilide. The pH optimum of midgut extracts was acidic (pH 4), implying that acidic proteases predominate. However, protease activity was inhibited substantially by both aprotinin and E-64, suggesting the presence of both serine and cysteine proteases in the midgut of the green mirid. 相似文献
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本文采用酶学分析方法研究了云斑尖塘鳢在正常摄食状态与饥饿的状态下胃、肠及肝胰脏组织中蛋白酶、淀粉酶和脂肪酶的活性。结果显示,在30℃的条件下,正常摄食组样本在酸性条件下的蛋白酶活力表现为:胃后肠肝胰脏前肠,中性和碱性条件下:后肠肝胰脏前肠及胃;饥饿组样本仅有胃表现出较高的酸性蛋白酶活性,其他器官的蛋白酶活性均很低。在正常和饥饿实验组中肝胰脏的淀粉酶活性均高于其他器官,胃肠的淀粉酶活性均较低。正常摄食组中脂肪酶活力后肠肝胰脏;而在饥饿组中仅有肝胰脏检测到脂肪酶活性。结果表明,云斑尖塘鳢适度饥饿组较正常摄食组消化酶活性大幅降低;其高蛋白酶活力及中等脂肪酶活力与其肉食性相一致;此外云斑尖塘鳢也具备少量的淀粉消化能力。 相似文献
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Six sets of feeding experiments were carried out using formulated diets containing prawn head waste (PW), chicken intestine waste (CW), banana flower (BF), cauliflower waste (CAU) Dolicos lab lab (DLL) and groundnut leaf (GNL) in four levels of inclusion (15, 30, 45 and 60%) to assess the pattern of distribution and activities of digestive enzymes like cellulase, amylase, maltase, invertase, protease and lipase in the digestive tracts of Labeo rohita fingerlings. A control group of fish was fed with diets containing antibiotics to destroy the digestive tract microflora which may induce digestive functions. In general, the activity of digestive enzymes depended on the amount and type of the ingredients present in the diets ingested by the fish. Test animals showed both endogenous and bacterial cellulase activities which suggests the necessity for including cellulose (plant protein source) as dietary ingredient. Occurrence of higher amount of cellulase in the foregut and amylase in the fore and midgut influenced by DNL and GNL diets revealed the possibility of including less than 40% of the respective ingredients in the diet of rohu. Maltase and invertase were highly influenced by GNL, DLL and BF diets than PW and CW diets. More than 40% inclusion of PW and CW was found to increase protease and lipase secretion in the midgut and hindgut regions. The higher secretion of lipase in the midgut suggested the physiological versatility for lipid digestion in rohu fingerlings. 相似文献
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It has been shown that protease activity increases and amylase activity decreases from the first to the fifth intestinal segment
of pike, while lipase and esterase activities vary within fairly narrow limits. The level of proteolytic enzyme activities
increases in pikes infected with Triaenophorus nodulosus (Pallas), but the invasion has no effect on amylase, lipase, or esterase activities. The T. nodulosus infection of pike had no substantial influence on glycogen or protein content in the hepatopancreas of fish. However, it
was noted that the ratio of protease and amylase activities in the intestines changed toward an increase in the share of proteases
and the share of protein in the hepatopancreas of infected fish. 相似文献
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Lara P Ortego F Gonzalez-Hidalgo E Castañera P Carbonero P Diaz I 《Transgenic research》2000,9(3):169-178
Nicotiana tabacum plants were transformed with the cDNA of barley trypsin inhibitor BTI-CMe under the control of the 35S CaMV promoter. Although the transgene was expressed and the protein was active in the homozygous lines selected, growth of Spodoptera exigua (Lepidoptera: Noctuidae) larvae reared on transgenic plants was not affected. The protease activity in larval midgut extracts after 2 days feeding on transformed tobacco leaves from the highest expressing plant showed a reduction of 25% in the trypsin-like activity compared to that from insects fed on non-transformed controls. The susceptibility of digestive serine-proteases to inhibition by BTI-CMe was confirmed by activity staining gels. This decrease was compensated with a significant induction of leucine aminopeptidase-like and carboxipeptidase A-like activities, whilechymotrypsin-, elastase-, and carboxipeptidase B-like proteases were not affected. 相似文献