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1.
The study was designed to determine whether leucine-enkephalin (L-ENK) was present in the digestive system of the scallop Chlamys farreri. The results indicate that L-ENK was present in the epithelium and connective tissue of mouth labia, labial palps, intestine, rectum, and stomach of the scallop Chlamys farreri. Moreover, it was also found that isolated cells showing L-ENK immunoreactivity were detected between the epithelial cells and the basal lamina in the principal hepatopancreatic ducts, and a few immunoreactive cells and fibers were observed between the hepatopancreatic tubules. Our report constitutes the first characterization of L-ENK in the digestive system of the scallop Chlamys farreri, and demonstrates its origin in simpler animals.  相似文献   

2.
The present experiment was conducted to study effects of Cu, Fe and Zn on activities of digestive enzymes of the hybrid tilapia Oreochromis niloticus×Oreochromis aureus. The acidic protease activities increased 65·5 and 55·1% by addition of homogenates of digesta‐containing stomach with copper (75 mg l−1) and zinc (50 mg l−1) respectively. Addition of Cu and Zn increased the activities of protease in the hepatopancreas homogenates by 132·7 and 38·1% respectively, and reduced the activity of protease in the digesta‐containing intestine homogenates by 11·0 and 13·8% respectively. Addition of Fe (50 mg l−1) increased the acidic protease activity by 96·7% but did not alter the activities of protease in the intestine and hepatopancreas. Addition of Cu markedly inhibited activities of amylase in intestine and hepatopancreas homogenates, while Zn addition showed no effects. Addition of Fe reduced activities of amylase in the intestine homogenates by 47·9% but had no effect on amylase activities in the hepatopancreas. When Cu (75 mg kg−1), Fe (50 mg kg−1) and Zn (50 mg kg−1) were supplemented to basal diet for 3 weeks, the activities of amylase in hepatopancreas homogenates increased 125·3, 215·6 and 70·0%, respectively, the activities of amylase in intestine increased 79·8, 74·6 and 48·5%, respectively, and the activities of lipase in intestine increased 90·5, 149·8 and 84·0%, respectively. Supplementation of Cu, Fe or Zn into diet had no effects on activity of protease in all digestive organs. Therefore, the results suggest that effects of Cu, Fe and Zn on activity of digestive enzymes in vitro were different from those seen in vivo, and that the positive effects of Cu, Fe and Zn supplemented to fish diet would be valuable information for formulating fish feed.  相似文献   

3.
采用抗生物素-生物素-过氧化物酶法(ABC法)的免疫组织化学技术,对γ-氨基丁酸(GABA)在栉孔扇贝(Chlamys farreri)消化系统各组织器官中的分布进行了定位研究。结果表明,栉孔扇贝的唇瓣、口唇、肠道的上皮细胞均呈GABA阳性反应,阳性反应物质呈颗粒状分布且多集中于上皮细胞游离端;胃上皮中未见GABA阳性反应;肝胰腺的上皮细胞及部分结缔组织中呈现GABA阳性反应,其中部分上皮细胞中的阳性反应物质呈团块状分布。GABA在栉孔扇贝消化系统除胃以外的各器官均有分布,推测其可能参与消化功能的调节作用。  相似文献   

4.
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   

5.
pH值对中国龙虾消化酶活力的影响   总被引:2,自引:0,他引:2  
姜永华  颜素芬 《动物学报》2008,54(2):317-322
采用酶学分析方法研究了pH对中国龙虾胃蛋白酶、类胰蛋白酶、淀粉酶、纤维素酶和脂肪酶活力的影响。结果表明,在设定的pH范围内,中国龙虾各消化酶的活力均随着pH的升高呈现先升后降的变化趋势。其中,胃、肠、肝胰腺内胃蛋白酶最适pH均为2.2,类胰蛋白酶最适pH分别为8.8-9.2、8.4、8.8,淀粉酶最适pH分别为7.0、7.0、7.4,纤维素酶最适pH分别为4.2、4.2-4.6、5.4,脂肪酶最适pH分别为7.2-7.6、7.2、6.8-7.2。同时测得中国龙虾胃、肠、肝胰腺内的生理pH分别为5.33、6.93、6.60。中国龙虾的消化酶活力存在器官特异性。在最适pH下,胃蛋白酶活力顺序为胃>肠>肝胰腺,类胰蛋白酶、纤维素酶、脂肪酶的活力顺序均为肝胰腺>肠>胃,淀粉酶的活力顺序为肠>肝胰腺>胃。  相似文献   

6.
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   

7.
应用酶学分析法测定了树麻雀Passer montanus春季的腺胃、肌胃、小肠、大肠、肝脏和胰脏组织中淀粉酶、蛋白酶和纤维素酶的活力.结果表明,不同组织中的消化酶活力差异显著,淀粉酶和蛋白酶以胰脏中活力最高,腺胃次之,纤维素酶均较低;同一组织中不同消化酶的活力差异显著,淀粉酶活性最高,蛋白酶次之,纤维素酶活力最低.这些差异提示消化酶活力大小与器官分化有关,并受食物组成的影响,因此产生了不同的酶活力分布.这是树麻雀长期适应东北地区寒冷环境的生存策略之一.  相似文献   

8.
植酸酶对草鱼和新吉富罗非鱼消化酶活性的影响   总被引:3,自引:0,他引:3  
植酸酶能水解植酸络合物,释放被植酸束缚的各种营养因子,因此能有效解除植酸与内源性消化酶的结合,促进消化酶的作用。本实验在全植物性饲料中添加植酸酶,研究其对草鱼(Ctenopharyngodon idellus)和新吉富罗非鱼(Oreochromis niloticus)淀粉酶及蛋白酶比活力的影响。以全植物性饲料为阴性对照组,添加磷酸氢钙(dibasic calcium phosphate,DCP)实验组为阳性对照组,另设4个不同梯度的植酸酶实验组(250 U/kg、500 U/kg、1 000 U/kg和2 000 U/kg)。实验选取健壮、规格齐整平均体质量为(12.59±0.09)g的草鱼和平均体质量为(9.59±0.12)g的新吉富罗非鱼,分别随机分为6个组,每组5个平行,每个平行20尾鱼。养殖8周后,草鱼平均体质量(18.29±0.63)g,新吉富罗非鱼平均体质量为(24.68±1.34)g,抽样取出胃、肠和肝胰脏用来分析淀粉酶和蛋白酶比活力。结果表明,植酸酶对无胃鱼草鱼和有胃鱼罗非鱼淀粉酶及蛋白酶比活力都有显著的促进作用。相比较而言,植酸酶对罗非鱼的应用效果较明显,低剂量就能显著提高其淀粉酶及蛋白酶比活力(P<0.05)。当植酸酶添加量达到1 000 U/kg时,草鱼和罗非鱼淀粉酶及蛋白酶比活力均达到峰值,此时,罗非鱼淀粉酶和蛋白酶比活力与阳性对照组无显著差异(P>0.05),而草鱼肝胰脏蛋白酶比活力显著高于阳性对照组(P<0.05)。植酸酶2 000 U/kg实验组,罗非鱼淀粉酶和蛋白酶比活力与1 000 U/kg植酸酶实验组无显著差异(P>0.05),但草鱼肝胰脏蛋白酶比活力显著低于1 000 U/kg植酸酶实验组(P<0.05)。因此,本实验条件下,植酸酶在草鱼和新吉富罗非鱼全植物性蛋白质配合饲料中的适宜添加量均为1 000 U/kg,生产实践中可通过添加植酸酶部分替代无机磷源。  相似文献   

9.
The ability to utilise dietary components differs among fish species. Digestive enzymes may be used to determine the efficiency of the digestive process. In this study, the activities of the digestive enzymes in Tilapia rendalli, Oreochromis mossambicus and Clarias gariepinus were explored. Protease, amylase, lipase and cellulase activities were measured in different parts of the digestive tract of the three fish species. The pH dynamics along the digestive tract were monitored. In all fish species, the presence of food led to a reduction in stomach pH, whereby pH values of 1.54, 1.58 and 2.01 were recorded 12 h after feeding in O. mossambicus, T. rendalli and C. gariepinus, respectively. Protease and amylase activities were significantly higher (P < 0.05, anova ) in the tilapias than in C. gariepinus. The tilapias may be pre‐adapted to produce more protease and amylase to digest plant material, which is more difficult to digest than animal matter. In all species amylase activity was significantly higher in the proximal intestine than in the other parts of the digestive tract (P < 0.05, anova ). The highest protease activity was recorded in the distal intestines. This is because of the alkaline pH recorded in the proximal and distal intestines, which favours amylase and protease activity, respectively. Lipase activities were significantly higher (P > 0.05) in C. gariepinus than in both tilapias. Marginal cellulase activities were recorded in all species. It is inferred here that phylogeny and not diet may be the main factor influencing enzyme activities, as all fish were fed a similar diet.  相似文献   

10.
The present work examines the temporal appearance and degree of activity of digestive enzymes of pancreatic and intestinal origin (amylase as well as neutral and alkaline proteases) together with the evolution of the ontogenic development of the intestine and pancreas during the first month of free‐living (30 days post‐hatch–[dph]) of the sturgeon Acipenser naccarii. In addition, the influence of exogenous live feeding with Artemia salina on the detection of digestive enzymes was studied. Shown are that in the first life stages of the A. naccarii, from the time of fertilisation to the juvenile stage, the following events related to its digestive physiology occurred: digestive enzymes were detected in the embryo stage within the egg, presumably related to the hatching gland; in the free‐living embryo stage, opening of the mouth was at 10 dpf and protease and amylase digestive activities occurred due to an early differentiation of the pancreas and intestine (12–13 dpf). At this stage, digestive enzymatic activities are partly owing to the live feed offered before disappearance of the yolk reserves (14 dpf); the expulsion of the melanin plug and the appearance of a continuity of the digestion tract (16 dpf) together with the disappearance of the yolk reserves (17 dpf) mark the passage from the free‐living embryo phase to the juvenile stage; finally, from the first month after hatching in this sturgeon species, there is a stabilisation in digestive amylase and protease activities together with a fully developed digestive structure. The contribution of enzymes from prey in the detection of enzymatic activities determined in the fish was beyond doubt; therefore these exogenous enzymes must also have a certain physiological importance. Subsequent work will be needed to clarify the importance of digestive processes of the exogenous enzyme pool from live feed as well as to assess the possibility of shortening the weaning period.  相似文献   

11.
&#  &#  &#  &#  &#  &#  &#  &# 《水生生物学报》2015,39(4):653-660
文章研究了不同盐度对花鳗鲡(Anguilla marmorata)幼鳗和太平洋双色鳗鲡(A. bicolor pacifica)幼鳗生长性能及消化酶活力的影响。将花鳗鲡幼鳗(9.760.36) g和太平洋双色鳗鲡幼鳗(11.820.04) g分别在淡水(盐度0)与盐度5、10、18水体中养殖30d, 测量每组实验鱼总重后检测胃、肠道和肝脏蛋白酶、淀粉酶和脂肪酶的活力。结果表明, 花鳗鲡和太平洋双色鳗鲡在各盐度处理中存活率均为100%, 未出现死亡。两种鳗鲡在淡水中生长良好, 特定生长率最高, 而饵料系数最低。盐度对花鳗鲡幼鳗和太平洋双色鳗鲡幼鳗消化酶活力的影响存在差异, 其中花鳗鲡胃、肠道和肝脏蛋白酶活力在各盐度处理中均无显著变化(P0.05), 淀粉酶和脂肪酶活力均随盐度的增加而下降; 太平洋双色鳗鲡胃蛋白酶活力在盐度10时最大, 肝蛋白酶活力在盐度18时最大, 而淀粉酶和脂肪酶活力在各盐度处理组无显著变化(P0.05)。这表明盐度对花鳗鲡胃、肠道和肝脏的淀粉酶和脂肪酶活力具有抑制作用, 对太平洋双色鳗鲡的蛋白酶活力有一定的激活作用。在相同盐度条件下, 不同消化器官中同种消化酶活力存在差异, 各盐度的两种鳗鲡肠道中淀粉酶和脂肪酶的活力均显著高于肝脏和胃(P0.05), 胃中蛋白酶活力高于肝脏和肠道, 但不显著(P0.05)。研究发现两种鳗鲡体内脂肪酶活力相对较高, 表明其对脂肪具有较强的消化能力。建议在配制花鳗鲡幼鳗和太平洋双色鳗鲡幼鳗饲料时, 适当提高粗脂肪比例, 有助于促进对营养物质的消化吸收, 提高养殖效益。    相似文献   

12.
The digestive ability of four sympatric land crabs species (the gecarcinids, Gecarcoidea natalis and Discoplax celeste and the anomurans, Birgus latro and Coenobita perlatus) was examined by determining the activity of their digestive enzymes. The gecarcinids are detritivores that consume mainly leaf litter; the robber crab, B. latro, is an omnivore that preferentially consumes items high in lipid, carbohydrate and/or protein; C. perlatus is also an omnivore/detritivore. All species possess protease, lipase and amylase activity for hydrolysing ubiquitous protein, lipid and storage polysaccharides (glycogen and starch). Similarly all species possess enzymes such as N-acetyl-β-d-glucosaminidase, the cellulases, endo-β-1,4-glucanase and β-glucohydrolase and hemicellulases, lichenase and laminarinase for the respective hydrolysis of structural substrates chitin, cellulose and hemicelluloses, lichenan and laminarin. Except for the enzyme activities of C. perlatus, enzyme activity could not be correlated to dietary preference. Perhaps others factors such as olfactory and locomotor ability and metabolic status may determine the observed dietary preferences. The digestive fluid of C. perlatus possessed higher endo-β-1,4-glucanase, lichenase and laminarinase activities compared to that of the other species. Thus, C. perlatus may be efficient at digestion of cellulose and hemicellulose within plant material. Zymography indicated that the majority of protease, lipase, phosphatase, amylase, endo-β-1,4-glucanase, β-glucohydrolase and N-acetyl-β-d-glucosaminidase isozymes were common to all species, and hence were inherited from a common aquatic ancestor. Differences were observed for the phosphatase, lipase and endo-β-1,4-glucanase isozymes. These differences are discussed in relation to phylogeny and possible evolution to cope with the adoption of a terrestrial diet.  相似文献   

13.
大熊猫胃肠道中消化酶活力的分析   总被引:1,自引:0,他引:1  
为了研究大熊猫对食物的化学性消化特点和机制,测定了9只大熊猫唾液和3只大熊猫胃肠道中主要消化酶的活力,并与其他动物进行了比较.结果显示,大熊猫唾液呈碱性,蛋白酶和淀粉酶等消化酶活力低;肠道中淀粉酶活力高,而脂肪酶活力明显低于棕熊.大熊猫小肠粘膜中存在显著量的蔗糖酶、乳糖酶和麦芽糖酶活力.另外,在1只大熊猫胃和直肠液中检测到了少量纤维素酶活力.研究结果提示,大熊猫唾液直接参与食物消化的作用可能很弱;大熊猫对淀粉类食物有很好的消化能力,但对脂肪类食物消化能力相对不高.大熊猫胃肠道消化酶的活力特点适应其消化天然食物中的营养物质.  相似文献   

14.
The digestive enzymes of two stoneflies species, Hemimelaena flaviventris and Isoperla morenica, were studied for the first time. These species are temporary water inhabitants and exhibit great feeding plasticity. Although they are traditionally referred to as predators, a previous study revealed that H. flaviventris incorporates some diatoms into its diet in addition to feeding usually on several prey, and I. morenica (in that study under the name of I. curtata) only feeds on animals occasionally. The enzymatic activities of digestive amylase, lipase, protease, trypsin and chymotrypsin were determined for each species at the same developmental stage. The results show that H. flaviventris has a greater digestive enzymatic pool and higher relative and absolute protease, lipase and trypsin activities than I. morenica. The latter has a relative higher amylase activity. As higher amylase activity is typical of phytophagous species and higher protease activity typical of carnivorous species; these results reveal that H. flaviventris is a more efficient zoophagous species than I. morenica. The ecological implications of these findings, including the higher secondary production of H. flaviventris in its habitat, are discussed.  相似文献   

15.
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   

16.
The study was designed to determine whether leucine-enkephalin (L-ENK) and delta receptor were present on the haemocytes of the scallop Chlamys farreri, and investigate the effects of L-ENK on the activity of catalase (CAT) and glutathione (GSH) level in haemolymph of the scallop. Lots of haemocytes immunoreactive to anti-L-ENK and -delta receptor sera were observed. The CAT activity and GSH level were investigated after 1, 5, and 50 μg/ml of L-ENK were added into the haemolymph of the scallop C. farreri. The CAT activity in haemocyte lysate supernatant (HLS) and supernatant were enhanced with increasing concentration of L-ENK. It was also found that the resultant HLS and supernatant GSH content was induced by L-ENK. Both the resultant HLS and supernatant CAT activity and GSH content was highest when the concentration of L-ENK was 50 μg/ml. By binding with opioid neuropeptide receptors, the opioid neuropeptides can regulate the intracellular and extracellular CAT activity and GSH content. Overall, the data strongly suggests an involvement of opioid peptides in the regulation and improvement of the antioxidant defence systems of the scallop C. farreri.  相似文献   

17.
以酶学分析方法研究了虎纹蛙消化道淀粉酶和脂肪酶的分布以及pH和温度对这两种消化酶活力的影响。结果表明:在各自生理pH值条件下,虎纹蛙消化道不同部位淀粉酶活力大小顺序依次为前肠〉中肠〉后肠〉食道〉胃,胃和肠淀粉酶最适pH值分别为8.6和7.0,最适温度分别为35℃和40℃。脂肪酶活力大小顺序依次为中肠〉后肠〉前肠〉胃〉食道,各部位之间差异显著(P〈0.05),胃和肠脂肪酶的最适pH值均为9.0,最适温度分别为50℃和55℃。  相似文献   

18.
Muhsin  Tawfik M.  Salih  Talal H. 《Mycopathologia》2001,150(2):49-52
Sixteen fungal species were isolated from 182 specimens collected from four ruminants (buffalo, camel, cattle and sheep) in Southern Iraq. Fungi represented by five species of dermatophytes and eleven species of other fungi were screened for the activity of four enzymes; keratinase, proteinase, lipase and amylase. Keratinase was found to be produced by all of the dermatophytes and non-dermatophytes, except for Paecillomyces variottii and Scytalidium lignicola. However, high keratinase activity was expressed by the dermatophytic species particularly by Trichophyton mentagrophytes var. erinacei and Microsporum gypseum. Three dermatophytes viz. M. gypseum, T. verrucosum and T. mentagrophytes var. nodulare were capable of producing protease, lipase and amylase. Although, T. mentagrophytes var. erinacei showed high protease activity, it did not produce lipase and amylase. On the contrary most of the non-dermatophytic species revealed protease and lipase activities higher than the dermatophytes. The Curvularia spp. isolates showed the highest protease and amylase activity, while Aspergillus parasiticus revealed the highest activity of lipase and amylase. No correlation was observed between enzyme activity and the growth rate of the examined fungi. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

19.
Scorpion, one of the most ancient invertebrates was chosen, as a model of a primitive animal, to purify and characterize an amylase located in the hepatopancreas. The scorpion digestive amylase (SDA) was purified. Pure SDA was obtained after heat treatment followed by ammonium sulfate fractionation and three steps of chromatography. The pure amylase is not glycosylated and has a molecular mass of 59,101 Da determined by MALDI-TOF MS analysis. The maximal amylase activity was measured at pH 7.0 and 50 °C, in the presence of Ca2+ and using potato starch as substrate. The enzyme was able to hydrolyze also, glycogen and amylose. The 23 NH2-terminal amino acid SDA residues were sequenced. The sequence obtained is similar to those of mammalian and avian pancreatic amylases. Nevertheless, polyclonal antibodies directed against SDA failed to recognize classical digestive amylases like the porcine pancreatic one.  相似文献   

20.
【背景】马蜂(Vespa mandarinia Smith)可以防治多种田间害虫,还具有药用价值,其肠道菌群结构和功能还有待研究。【目的】获得马蜂肠道可培养细菌并筛选出具有产消化酶功能的菌株,为理解肠道菌对宿主的影响机理及功能菌株的利用提供科学依据和研究材料。【方法】采用传统细菌分离培养法获得马蜂肠道菌,结合形态学以及16S rRNA基因序列分析进行鉴定;利用水解圈法分别筛选产蛋白酶、脂肪酶、淀粉酶和纤维素酶菌株;通过测量水解圈D与菌落直径d的比值,比较不同细菌的产酶能力。【结果】在马蜂肠道中共分离出6属10种细菌,其中芽孢杆菌属5种,肠球菌属、葡萄球菌属、明串珠菌属、乳球菌属和不动杆菌属各1种。从获得的61个菌株中筛选出6个具有产消化酶功能的菌株。其中,苏云金芽孢杆菌V44具有产蛋白酶、淀粉酶、脂肪酶和纤维素酶4种消化酶的能力;粪肠球菌V6具有产淀粉酶、蛋白酶和脂肪酶3种消化酶的能力;蜡样芽孢杆菌V43具有产蛋白酶、淀粉酶和纤维素酶3种消化酶的能力;粪肠球菌V20、蜡样芽孢杆菌V19和维德曼氏芽孢杆菌V22均具有产蛋白酶的能力。【结论】马蜂肠道细菌资源较丰富,部分有产消化酶的功能,可帮助马蜂消化食物,对宿主健康有一定影响。本研究筛选的6个菌株都能产蛋白酶,其中菌株V43和V44分别具有最强产淀粉酶和脂肪酶的能力,是可进一步开发利用的肠道功能菌株资源。  相似文献   

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