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研究了象山港泥蚶(Tegillarca granosa)快速生长季(2020年5—11月)糖原、游离氨基酸和脂肪酸等代谢物的组成、含量及其变化,并对其营养特征变化进行了分析。结果显示,7—9月为泥蚶快速生长期,此期前后泥蚶生长缓慢。泥蚶肌肉糖原含量约5.6~11.1mg/g;牛磺酸、丙氨酸、谷氨酸和天冬氨酸是其主要的游离氨基酸;不饱和脂肪酸含量丰富,且主要为多不饱和脂肪酸。生长过程中几种生化代谢物含量变化显著:5—7月间,糖原含量显著降低、氨基酸和脂肪酸组成发生显著变化。7—9月间,糖原含量、生糖和呈味氨基酸含量显著升高、饱和及单不饱和脂肪酸含量显著降低,但脂肪酸组成结构无显著差异。11月,氨基酸及多不饱和脂肪酸含量均显著升高。11月泥蚶具有高的营养品质。本研究为泥蚶养殖管理及水产品营养研究提供参考。 相似文献
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金属硫蛋白(Metallothionein,MT)是一类富含半胱氨酸的小分子蛋白质,参与机体重金属解毒和金属元素代谢等生理过程。本研究采用RACE技术,克隆获得了菲律宾蛤仔(Ruditapes philippinarum)金属硫蛋白(RpMT)的全长cDNA序列。RpMT的cDNA全长为570bp,编码75个氨基酸,包含15个MT所特有的Cys-Xn-Cys结构。采用实时荧光定量PCR技术,分析了两种壳色菲律宾蛤仔(白蛤和斑马蛤)RpMT基因在Cd2+暴露后的表达变化。结果发现:Cd2+急性和亚慢性暴露均可导致两种壳色蛤仔消化腺和鳃组织RpMT基因表达量的显著上调;暴露后两种壳色蛤仔鳃组织RpMT基因表达量的增加幅度均高于消化腺组织,且以白蛤鳃组织基因表达水平的上调幅度较高。上述结果表明,RpMT可能在菲律宾蛤仔抵御Cd2+胁迫过程中发挥了重要作用。 相似文献
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Genetic responses to metal contamination in two clams: Ruditapes decussatus and Ruditapes philippinarum 总被引：1，自引：0，他引：1
Moraga D Mdelgi-Lasram E Romdhane MS El Abed A Boutet I Tanguy A Auffret M 《Marine environmental research》2002,54(3-5):521-525
Coastal ecosystems are subjected to a wide variety of disturbances, including those due to xenobiotics of agricultural and industrial origin. These pollutants as heavy metals can modify the genetic diversity of populations by favouring or counter-selecting certain alleles or genotypes by differential mortality. In the present study, two genetic markers (phosphoglucomutase and glucosephosphate isomerase) and a protein marker (metallothionein) were monitored in order to determine the impact of heavy metals in different clam populations. Analysis of the genetic structure of the clam populations examined reveals that those inhabiting environments contaminated by heavy metals exhibit a higher allelic diversity and possess alleles at PGM loci that could be selected by the presence of heavy metals. The evaluation of metallothionein levels using a specific polyclonal antibody developed in the Pacific oyster (Crassostrea gigas) demonstrated the existence of a relationship between metallothionein concentrations and the level of metal pollution for clam populations sampled from different sites. An inter-specific difference was also detected between Ruditapes decussatus and Ruditapes philippinarum living in sympatry at the same site, suggesting a differential response of these two species upon exposure to an identical heavy metal concentration. 相似文献
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福建长乐海域近江蛏营养成分分析与品质评价 总被引：1，自引：0，他引：1
测试分析了福建长乐海域近江蛏（Sinonovacula rivularis）新鲜软体部的营养成分,并与部分经济蛏类进行比较．结果表明,近江蛏软体部的出肉率为48．1％±6．0％,软体部中的水分、蛋白质、脂肪和灰分质量分数分别为84．9％、9．4％、1．6％、1．4％．近江蛏软体部中含有人体所需的17种氨基酸（除色氨酸未测外）,氨基酸含量为74．0mg／g,必需氨基酸（C EAA）占氨基酸总量（C TAA）的37．2％,鲜味氨基酸（C FAA）占氨基酸总量（C TAA）的49．6％,17种氨基酸中谷氨酸（Glu）含量最高．根据AAS和CS评价,第一限制性氨基酸为苯丙氨酸（Phe）．赖氨酸（lys）的AAS评分最高,超过FAO／WHO模式和鸡蛋蛋白质．软体部的必需氨基酸指数（I EAA）为100．06,必需氨基酸（EAA）与非必需氨基酸（NEAA）的比值（C EAA／C NEAA）为59．1％,必需氨基酸（EAA）与氨基酸总量（CTAA）的比值（C EAA／C TAA）为37．2％,构成比例均接近FAO／WHO提出的优质蛋白质标准．近江蛏软体部和足部的多不饱和脂肪酸（PUFA）含量高于饱和脂肪酸（SFA）的含量,多不饱和脂肪酸（PUFA）中又以高度不饱和脂肪酸（HUFA）的组成为主,并且n-3PUFA的含量明显高于n-6PUFA的含量;DHA和EPA含量丰富,软体部的EPA与DHA质量分数分别为4．4％、3．0％,EPA含量高于DHA的含量,两者之和分别占多不饱和脂肪酸（PUFA）的80．4％、81．1％．近江蛏足部的PUFA含量、Cn-3／Cn-6比值以及C EPA＋C DHA之和均高于软体部．近江蛏软体部中合有丰富的矿物质元素,尤其是Zn、Se含量十分丰富．表明近江蛏肌肉具有较高的营养价值．建议对近江蛏等底栖性贝类在食用前进行蓄养净化,并对其进行消费安全和人体健康风险评价． 相似文献
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The US Geological Survey has reported the presence of a metal contamination gradient in clam tissues, decreased condition indices, and irregular reproductive patterns have been reported in the Asian clam, Potamocorbula amurensis, from San Francisco Bay. If metals are driving the observed patterns in the field, then biomarkers of exposure, and possibly deleterious effect, should show a corresponding gradient. In this study, biomarkers from sub-cellular to tissue levels of biological organization were assessed in P. amurensis collected from the Bay or exposed to cadmium in the laboratory. Cellular and tissue alterations were assessed using histopathology and enzyme histochemistry (EH). Alterations in the ovary, testis, kidney, and gill tissues were most common at the most contaminated station when data were averaged over a 12-month sampling period. EH analysis indicated decreased active transport, energy status, and glucose oxidation in kidney and digestive gland at the most contaminated site which may indicate a decreased potential for growth. Ovarian lesions observed in feral Asian clams were experimentally induced in healthy clams by cadmium exposure in laboratory exposures. Our results suggest a contaminant etiology for tissue alterations. 相似文献
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福建省厦门海沧沿岸滩涂的缢蛏Sinonovacula constricta 的主要生殖期是10月,其两次高峰分别出现10月的上、下旬。缢蛏的性腺和消化腺发育过程中蛋白质、脂类、糖类与17种氨基酸的组成以及它们的组织化学反应的结果表明,在生殖周期中性腺与消化腺的蛋白质和脂类的变化大,而糖类都维持在低水平上,其最高量不超过9%干重。性腺和消化腺的蛋白贮存量随着性腺发育而增加,于成熟配子排放之前蛋白质量达到最大。排放之后蛋白质量和脂量皆下降,而糖量在性腺中却略有增加。在8～9月,消化腺和性腺内的脂量变化呈相反关系,表明当性腺形成过程它们之间可能有转化作用。性腺、消化腺的组化反应结果与它们的生化成分的分析相一致。性腺与消化腺的生化组成的相互关系表明,与脊椎动物相类似,缢蛏消化腺也有储存营养物质的作用。 相似文献
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乐清湾泥蚶肉营养成分的分析及评价 总被引：2，自引：1，他引：1
对乐清湾泥蚶(Tegillarca granosa)肉营养成分进行了分析。结果表明,乐清湾泥蚶肉(干基)粗蛋白含量为67．75％;蛋白质氨基酸评价为85．4分,色氨基酸是惟一的限制性氨基酸。在蛋白质氨基酸组成中。以呈鲜味、甘味或与之有关的谷氨酸、冬氨酸、丙氨酸、甘氨酸、脯氨酸、丝氨酸6种氨基酸含量最高,占氨基酸总量的46．71％;不饱和脂肪酸含量也相当高．尤其是高度不饱和脂肪酸C20：5(EPA)和C22：6(DHA),占脂肪酸总含量的31．62％;此外还含有多种人体必需的维生素、无机盐、微量元素等多种成分。 相似文献
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E. García-Luque T. A. DelValls C. Casado-Martínez J. M. Forja A. Gmez-Parra 《Marine environmental research》2004,58(2-5):671
We describe the effect of heavy metals Zn, Cd, Pb and Cu on the induction of methallothioneins on the clam Scrobicularia plana along a salinity gradient simulated under laboratory conditions. The clams were exposed to constant heavy metal concentrations in a dynamic estuary simulator during a 15-day assay to investigate possible induction of metal-binding proteins in them. The concentration of heavy metals in water was analysed. Clams were analysed for methallothionein concentrations. The speciation of Zn, Cd, Pb and Cu along the salinity gradient was modelled. Zn showed the highest concentrations and its prevalent species was the free ion. Intersite differences have been observed in methallothionein concentration and related to the salinity gradient. It seems that synthesis of methallothioneins is the result of physiological forces acting in concert with the changes in the chemical speciation of metals, owing to the trace metals uptake is controlled by means of an interaction of physiology and physicochemistry. 相似文献
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García-Luque E DelValls TA Casado-Martínez C Forja JM Gómez-Parra A 《Marine environmental research》2004,58(2-5):671-674
We describe the effect of heavy metals Zn, Cd, Pb and Cu on the induction of methallothioneins on the clam Scrobicularia plana along a salinity gradient simulated under laboratory conditions. The clams were exposed to constant heavy metal concentrations in a dynamic estuary simulator during a 15-day assay to investigate possible induction of metal-binding proteins in them. The concentration of heavy metals in water was analysed. Clams were analysed for methallothionein concentrations. The speciation of Zn, Cd, Pb and Cu along the salinity gradient was modelled. Zn showed the highest concentrations and its prevalent species was the free ion. Intersite differences have been observed in methallothionein concentration and related to the salinity gradient. It seems that synthesis of methallothioneins is the result of physiological forces acting in concert with the changes in the chemical speciation of metals, owing to the trace metals uptake is controlled by means of an interaction of physiology and physicochemistry. 相似文献
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为了解TYR基因与蛤仔免疫的关系,本实验利用荧光定量PCR技术研究了菲律宾蛤仔五个群体(白蛤、白斑马蛤、斑马蛤、养殖和野生群体)的鳃组织和肝胰腺组织在LPS胁迫下TYR基因在不同时间(0 h、3 h、12 h、24 h、48 h)的表达特性。结果表明,在LPS注射后鳃组织中TYR6基因表达水平在白蛤和白斑马蛤3 h、6 h、12 h,野生蛤仔3 h,斑马蛤3 h、6 h,养殖群体6 h、12 h显著上调(P0.05),3h野生蛤仔和斑马蛤达到峰值, 6 h白蛤、白斑马蛤、养殖群体达到峰值(P0.05);在肝胰腺中,养殖群体和白斑马蛤6 h,白蛤6 h、24 h,野生群体24 h,斑马蛤3 h显著上调, 3 h野生蛤仔和斑马蛤达到峰值,6h养殖群体、白蛤、白斑马达到峰值(P0.05);鳃组织中TYR10基因表达水平在白蛤、野生群体和白斑马蛤3 h,养殖群体3 h、6 h,斑马蛤3 h、12 h显著上调(P0.05),肝胰腺组织中TYR10基因表达水平在白蛤3 h,野生群体3 h、6 h、12 h,斑马蛤、养殖群体6 h显著上调(P0.05),推测TYR基因在五个菲律宾蛤仔群体的鳃和肝胰腺中参与了免疫应答。通过对TYR基因的氨基酸序列进行二级结构分析和系统发育树分析,找到两个铜离子结合位点和6个组氨酸残基,并发现TYR6基因和长牡蛎同源性最高,为39.43%, TYR10基因和大珠母贝同源性最高,为51.04%。本文首次探讨在LPS胁迫下菲律宾蛤仔TYR基因的表达特性,为进一步探究TYR基因与菲律宾蛤仔免疫应答机制提供参考。 相似文献
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以5日龄中华鳖稚鳖为实验动物,采用静水停食实验法,在水温(27.4±1.3)℃条件下,开展了Hg2+、Cr6+、Cu2+、Zn2+对中华鳖稚鳖的急性毒性和加和等毒性强度联合毒性试验。结果表明,4种重金属离子对中华鳖稚鳖均呈现以蓄积为主导的急性毒发效应,Cr6+、Zn2+对中华鳖稚鳖的急性致毒高峰期明显滞后于Hg2+、Cu2+;4种重金属离子毒性大小依次为Hg2+、Cu2+、Cr6+、Zn2+,其对中华鳖稚鳖96h的半致死质量浓度分别为5.98、16.42、28.90和91.88mg/L;所构建的中华鳖稚鳖累积死亡概率与重金属质量浓度和实验时间之间的数学模型,以及半致死时间-质量浓度回归方程,可作为侦查和分析重金属离子排放时间和致中华鳖稚鳖大量死亡时间的重要计算工具;Hg2+、Cr6+、Cu2+、Zn2+离子两两组合在加和等毒性强度下对中华鳖稚鳖96h联合急性毒性所呈现的致毒特征与离子种类及其毒性强度匹配情形密切相关。 相似文献
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重金属对扁额细首纽虫金属硫蛋白的影响 总被引：1，自引：0，他引：1
生物体内金属硫蛋白含量变化,可作为环境中重金属污染的生物标志物.通过暴露实验研究了扁额细首纽虫Cephalothrix simula暴露在不同浓度的铜,锌和镉溶液96 h,其体内金属硫蛋白含量的变化规律.结果表明3种重金属离子的胁迫作用均导致金属硫蛋白含量增加,在实验初期(6～24 h),金属硫蛋白含量达到高峰;金属硫蛋白含量与暴露溶液金属浓度具有明显的剂量～效应关系,金属离子浓度越高,金属硫蛋白含量越高;锌离子诱导金属硫蛋白合成的作用大于铜、镉离子. 相似文献
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黄河口河海混合过程水中重金属的变化特征 总被引：2，自引：0，他引：2
在枯水期、丰水期采集黄河口的表底层水样,分析全水样铜、铅、锌、镉、铬、砷、汞浓度.结果表明黄河口水中重金属浓度:丰水期＞枯水期,且底层水总重金属浓度要高于表层.在从河入海过程中,总重金属浓度在河海混合过程阶段浓度变化较大,在枯水期整体上是由河向海的总重金属浓度逐渐降低,但部分金属在距离A03站位12.5 km附近有明显低值区,随后又有升高,主要原因为沉积物的再悬浮;在丰水期距离A03站点11.5～15 km,重金属浓度有低谷河段,随后又有一峰值,该位置比枯水期推后了约1.3 km.主成分分析表明,河水流量的大小和咸淡水的混合导致的泥沙的再悬浮和盐度影响到河海混合过程及河口重金属的浓度变化趋势. 相似文献
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In order to establish a new method to eliminate toxicities of heavy metal ions to larval penaeid shrimp, the effects of copper, zinc, lead and cadmium ions on larval metamorphosis of Penaeus chinensis at each stage were determined in detail, and two methods eliminating toxicities were compared. The results indicate that sensitivity of larvae to heavy metal ions decreases in the order of nauplii, protozoea, mysis and postlarvae. The phytoplankton food can reduce, by chetating, the toxicities of heavy metal ions. Both EDTA chelation and PHMA absorption can be used to eliminate the toxicities effectively and there is no significant difference between the two methods. EDTA is harmful to larval P. chinensis at high concentration but affects neither survival nor metamorphosis at below 10 mg/dm3. It is preliminarily observed that copper and zinc ions at low concentration are beneficial to the development of larvae after protozoea stage. It is suggested that it is unnecessary to e-liminate the effects of heavy 相似文献
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Hg,Cu,Cd,Zn 对真鲷仔鱼的急性毒性研究 总被引：5，自引：1，他引：5
本文采用静水生物试验法测定了Hg,Cu,Cd,Zn对真鲷仔鱼(2周龄)的急性毒性。结果表明:Hg,Cu,Cd,Zn对真鲷仔鱼24h的LC_(50)分别为0.025,0.31,5.00和3.70 mg/L,48h的LC_(50)分别为0.016,0.24,1.72和2.22mg/L,72h的LC_(50)分别为0.006,0.11,O.56和0.92mg/L,96h的LC_(50)分别为O.004,0.07,0.27和0.44 mg/L。Hg,Cu对真鲷仔鱼的影响极为显著,Zn,Cd的影响虽然很大,但比Hg,Cu低得多。Cd的毒性比Zn强,但毒理作用较为缓慢。4种重金属的毒性顺序为Hg>Cu>Cd>Zn。 相似文献
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A conventional amino acid analyzer was modified to allow detection of dissolved free amino acids in a direct injection of 0.5 to 2.0 ml of seawater. The amino acids were monitored fluorimetrically by reaction with o-phthaldialdehyde after column chromatography. The accuracies of two commonly employed desalting methods, cation exchange resin and copper Chelex, were determined by comparison with the direct injection method. After correcting the results of the desalting methods for the procedural blank and recovery rate for each individual amino acid, the amino acid compositions on a mole percent basis as determined by these methods resembled approximately the true composition determined by direct injection. However, on an absolute basis the cation resin method overestimates and the copper Chelex method underestimates the total amount of dissolved free amino acids. The reasons for these discrepancies are discussed. Using the direct injection method, the spectra of dissolved free amino acids in surface seawater samples from different locations were determined. As opposed to the relatively uniform patterns reported in most past investigations, the amino acid spectra found were highly variable. In a number of samples, the acidic amino acids dominated the spectra. Valine was also high in many samples. In a depth profile the deep samples were dominated by arginine. Application of the method to real-time shipboard analyses of dissolved free amino acids is discussed. 相似文献
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Biomarker responses in Macoma nasuta (Bivalvia) exposed to sediments from northern San Francisco Bay
Our study investigates biomarker responses and survival of Macoma nasuta exposed to sediments collected from six locations in northern San Francisco Bay. Biomarkers analyzed were stress proteins (hsp70) in gill, mantle and digestive gland, lysosomal membrane damage and histopathologic lesions. Sediments and clam tissues were analyzed for a comprehensive suite of heavy metals and trace organic pollutants. Sediment grain size and organic carbon content were determined. Clams accumulated metals, polyaromatic hydrocarbons (PAHs) and organochlorine pesticides (aldrin and p,p(')-DDT and its metabolites p,p(')-DDD and p,p(')-DDE). Pearson and Spearman correlation analysis revealed that mortality, hsp70 in gill and histopathologic lesion scores in gonads, and lysosomal membrane damage were significantly correlated with tissue concentrations of DDT and/or its metabolites. Tissue concentrations of metals, in particular nickel, chromium, and copper, were associated with macrophage aggregates in digestive gland and germ cell necrosis. Cadmium was linked to mortality and lysosomal membrane damage. 相似文献