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1.
建立了水产品中三磷酸腺苷(ATP)、二磷酸腺苷(ADP)、腺苷酸(AMP)、肌苷酸(IMP)、次黄嘌呤核苷(HxR)和次黄嘌呤(Hx)6种ATP关联化合物的高效液相色谱检测方法。样品中的ATP关联物经高氯酸提取并用氢氧化钠调节pH值至6.0-6.4后,以AQ-C18(250 mm×4.6 mm,5μm)柱为分析柱,0.02 mol/L KH2PO41-0.02 mol/L K2HPO4(V/V=1/1)的缓冲液为流动相进行洗脱,在254 nm波长下用高效液相色谱进行检测,外标法定量。研究表明,ATP、ADP、AMP、IMP和HxR线性范围为0.2-40.0μg/ml,Hx线性范围为0.1-20.0μg/ml,相关系数均大于0.999 0;ATP、ADP、AMP、IMP和HxR检出限为5.00 mg/kg,Hx检出限为2.5 mg/kg(S/N=3);对真鲷、鱼师鱼、鲑鱼、凡纳滨对虾和梭子蟹5种水产品进行3个浓度水平的加标实验,回收率在85.5%-105%之间,相对标准偏差(RSD)小于12.9%。实验结果表明,该方法简便、准确,适合于水产品中ATP关联物的测定。  相似文献   

2.
建立了水产品中β-阿朴-8′-胡萝卜素醛的高效液相色谱检测方法.样品采用抗氧化剂焦性没食子酸保护,酸化乙腈提取,二氯甲烷萃取,旋转蒸干后乙腈定容,高效液相色谱-紫外检测器检测,外标法定量.流动相乙腈+0.1%甲酸溶液=97+3,检测波长457 nm,色谱柱ZORBAX Eclipse XDB-C 18柱(4.6mm×150 mm,粒度5 μm).实验结果表明β-阿朴-8′-胡萝卜素醛在0.02~10.0 μg/mL范围内线性良好(r=0.999 95);检出限0.01 mg/kg,平均回收率62%~107%之间,平行样品的标准偏差≤6.1%.  相似文献   

3.
建立了用紫外和荧光检测器同时分析水产品中有色孔雀石绿和无色孔雀石绿的高效液相色谱法。有色孔雀石绿检测采用紫外检测器,波长588 nm;无色孔雀石绿采用荧光检测器,其激发波长265 nm,发射波长360 nm,流动相0.1 mol/L(pH4.5)的乙酸铵溶液∶乙腈(20∶80),流速1.5 ml/min。采用ZOBAX C18(250 mm×4.6 mm,5μm)色谱柱。加标量为10μg/kg和250μg/kg(有色孔雀石绿),回收率分别为60.2%和56.6%,相对标准偏差分别为10.1%和5.6%;加标量为2μg/kg和50μg/kg(无色孔雀石绿)时,回收率分别为95.2%和92.3%,相对标准偏差分别为10.8%和11.3%。该方法的最低检测限1.1μg/kg(孔雀石绿和无色孔雀石绿总量),可满足欧盟对水产品中孔雀石绿的检测要求。检测方法稳定,简便,灵敏度高,无需柱后氧化柱,适合同时进行水产品中有色孔雀石绿和无色孔雀石绿含量的检测。  相似文献   

4.
凡纳滨对虾样品经高氯酸去蛋白后,用Purospher STAR RP-18(150mm×4.6mm,5μm)色谱柱分离;流动相为0.1mol/L的磷酸二氢钾(pH 3.0)∶甲醇∶乙腈=70∶5∶25;在流速0.8mL/min,柱温25℃,进样量10μL的条件下,于荧光检测器激发波长280nm,发射波长340nm处进行检测。结果表明,该方法的线性范围为0.50~100.0μg/L,线性相关系数r2=0.9982,平均加标回收率为87.9%。  相似文献   

5.
汤水粉 《福建水产》2013,35(1):40-46
在水产品中八种磺胺类药物测定的高效液相色谱-柱后衍生法方法标准的基础上,对检测条件进行优化和改进,实现了水产品中八种磺胺类(磺胺嘧啶、磺胺噻唑、磺胺甲基嘧啶、磺胺二甲基嘧啶、磺胺甲噁唑、磺胺多辛、磺胺异噁唑、磺胺喹噁啉)药物残留的高灵敏检测.磺胺嘧啶、磺胺噻唑、磺胺甲基嘧啶和磺胺二甲基嘧啶线性范围:0.025 ~0.5 μg/mL;磺胺甲噁唑、磺胺多辛、磺胺异噁唑线性范围:0.05 ~ 1.0 μg/mL;磺胺喹噁啉线性范围:0.1~ 2.0 μg/mL.线性相关系数均大于0.9990.对鲈鱼空白样品进行八种磺胺类药物的加标实验,加标量为5 μg/kg ~ 100 μg/kg时,回收率在84.2% ~109%之间,相对标准偏差为1.64%~10.6%.  相似文献   

6.
建立了一种能够同时测定水产品中氧化三甲胺及其分解产物二甲胺和三甲胺的非抑制性离子色谱方法.样品使用10%三氯乙酸溶液浸提,浸提液通过离心,稀释过滤后直接进样;方法使用4mmol/L硝酸+3%乙腈作为淋洗液,色谱分离柱为Metrosep C4 150(150mm×4mm);二甲胺、氧化三甲胺和三甲胺的保留时间分别为6.22、8.21、9.09min,检出限分别为0.025、0.050、0.050mg/kg;该方法具有较好的线性相关性(r>0.999),RSD为1.41%~3.83%(n=5),加标回收率为91.5%~100.3%.通过比较,含有内源性甲醛的水产品样品中检出二甲胺,而不含有内源性甲醛的样品没有检测到二甲胺.  相似文献   

7.
本研究建立了动物源性水产品中16种除草剂的凝胶色谱-固相萃取净化、气相色谱-质谱分析方法.结果显示,样品通过二氯甲烷-乙酸乙酯混合溶液提取、凝胶渗透过滤及固相萃取柱净化,采用气相色谱-质谱联用方法测定,选择离子监测、外标法定量.二甲戊乐灵、草净津在4-200 μg/L浓度范围内,其余14种在2-100μg/L浓度范围内与其响应值呈良好的线性关系,相关系数(一不低于0.9970.扑灭津、阿特拉津、特丁津、西玛津、敌草净、扑草净、莠灭净、异丙甲草胺定量限均为1.0 μg/kg;乙草胺、甲草胺、丁草胺、丙草胺、环草津、西草净定量限均为1.5 μg/kg;二甲戊乐灵、草净津定量限均为2.0 μg/kg.平均回收率为67.2%-103.0%,相对标准偏差为5.1 %-9.5%.研究表明,该方法重现性好,回收率高,在精密度、准确度方面能满足残留检测要求,适用于水产品中16种除草剂残留的同时检测.用此方法检测了海参、牡蛎、扇贝等水产品中除草剂残留量,检出率最高的是莠灭净,其次是阿扑草净、特拉津、西草净、乙草胺,同时为进一步探讨除草剂污染对水产品质量安全的影响奠定基础.  相似文献   

8.
利用高效液相色谱-荧光检测器分析了牙鲆肌肉中恩诺沙星及其代谢产物环丙沙星的含量。样品前处理方法为:以磷酸盐缓冲液作为提取液,样品经均质、离心后,用正己烷除去脂肪,再用ODS(C18)固相萃取柱净化,洗脱液蒸发浓缩后,乙腈溶解残渣。其色谱条件为:色谱柱XDB-C18柱(250mm×4.6mm);流动相0.01mol/L四丁基溴化铵(pH3.0)∶乙腈=94∶6(v/v);流速1.5ml/min;进样量10μl;柱温40℃;荧光检测器激发波长280nm、发射波长450nm。结果表明,在牙鲆肌肉中添加50、100和200μg/kg3个水平的恩诺沙星和环丙沙星混合物标准后,其回收率均大于80%,相对标准偏差小于10%。恩诺沙星与环丙沙星检出限均为10μg/kg。  相似文献   

9.
以罗非鱼为对象测定血浆中的肉碱含量,就流动相、柱温对色谱峰的影响等方面对样品处理方法及衍生化反应的条件进行研究,建立相应的高效液相色谱法,Kromasil Sil色谱柱(250mm×4.6mm,5μm),流动相为乙腈—柠檬酸缓冲液(90∶10,体积比)。每1000mL流动相中加入0.25mL三乙胺,流速1.2mL/min,柱温35℃,检测波长260nm,进样量为20μL。选取10%的对溴苯乙酰基溴为衍生试剂,70℃水浴90min。方法学上考察结果表明,该方法专属性高,其线性回归方程和相关系数分别为y=0.08376x+0.09663(n=6,r~2=0.9995),最低检测限为1μmol/L,日内和日间变异系数分别为1.79%~5.56%、9.83%~11.81%,平均回收率为95.83%,12h峰面积变化相对标准偏差为6.58%,可将其作为检测L-肉碱的分析方法。  相似文献   

10.
建立同时检测鲫(Carassuys auratus Linnaeus)血浆和肌肉中邻苯二甲酸二甲酯(DMP)和邻苯二甲酸二乙酯(DEP)的高效液相色谱方法,进行初步的代谢动力学研究.血浆样品经液-液萃取,肌肉样品经液-液萃取和固相小柱处理后,以乙腈:水= 40:60(V/V)为流动相,流速1.0 mL/min,采用SHIMADZU ODS柱(150 mm×4.6 mm; i.d., 5 μm)色谱柱分离.测定鲫经口染毒后血浆和肌肉中DMP和DEP的浓度.结果表明,标准曲线线性范围为0.05~10.0 μg/mL,线性关系良好(r>0.99),定量限为0.05 μg/mL,回收率95%以上,日内变异系数和日间变异系数均低于15%.经口染毒48 h内,鲫血浆和肌肉中均能检测到DMP和DEP的残留.该法操作简便、快速、灵敏、准确,已经初步用于鲫血浆和肌肉中DMP和DEP的代谢动力学和残留研究.  相似文献   

11.
12.
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China.  相似文献   

13.
The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna.  相似文献   

14.
Growth hormone (GH) and reproduction: a review   总被引:5,自引:0,他引:5  
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations.  相似文献   

15.
Protein and amino acid composition of the mantle of juvenile O ctopus vulgaris (Cuvier, 1797) during fasting for 27 days were determined. Average protein content of octopus mantle was of 711.19 ± 46.80 g kg?1 DW, and it decreased with increasing fasting days. The non‐essential amino acids content was higher (486.18 ± 11.08 g kg?1 protein) than essential amino acids (425.82 ± 9.15 g kg?1 protein) at the start of the experiment (unstarved animals). The results suggest that the amino acid profile of the mantle where the most abundant amino acids are Arg, His, Lys, Gly, Leu and Pro could indicate a prolonged fasting condition (>20 days) or poor nutrition of O . vulgaris. This study supports the idea of using mantle for metabolic needs of starved O . vulgaris suggesting that the degradation pathway of amino acids to pyruvate and tricarboxylic acid cycle intermediates was favoured contrary to the degradation pathway of ketogenic amino acids. Special considerations should be taken concerning Thr, Ile, Ser, Ala, Asx (Asp, Asn), Glx (Glu, Gln) (because of their fast intake) and Lys and His (due to their stable contents) during a prolonged period of fasting.  相似文献   

16.
17.
In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg.  相似文献   

18.
Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation.  相似文献   

19.
The endemic, anadromous cyprinidChalcalburnus tarichi is the only fish species known to occur in alkaline Lake Van (Eastern Anatolia, Turkey). EightC. tarichi were maintained individually in Lake Van water (17 – 19°C; pH 9.8; 153 mEq·I–1 total alkalinity; 22 total salinity) and tank water samples analyzed for 24 h in 2 to 4 h intervals. At zero time, < 1µM ammonia was present and urea was undetectable in the tank water; at 24 h, total ammonia and urea made up 114±32 and 35±25µM, respectively. Over the experimental period, ammonia-N and urea-N excretion averaged 1041±494 and 607±169moles·kg–1 fish·h–1, respectively. The extent of urea excretion was highly variable between specimens. Uric acid excretion was not detectable.Urea was present at high concentrations in all tissues and plasma (25 – 35moles·g–1·ml–1) of freshly caughtC. tarichi; total ammonia content of the tissues was by a factor of 1.9 (liver) to 3.0 (brain) lower. High arginase activity (2.4±0.2 U·min–1·g–1) was detected in the liver ofC. tarichi but ornithine carbamoylphosphate transferase, a key enzyme of the ornithine-urea-cycle, was absent. Ureagenesis is likely through degradation of arginine and/or uricolysis. High glutamine synthetase activity (11±0.6 U·min–1·g–1) and low ammonia content in brain suggest that, like other teleosts,C. tarichi has an efficient ammonia detoxification in the brain, but in no other tissue.Nitrogenous waste excretion at alkaline pH is discussed. The ability ofC. tarichi to excrete high levels of ammonia at extremely alkaline pH is unique among teleosts studied so far. The mechanism of ammonia excretion under Lake Van conditions remains to be elucidated.  相似文献   

20.
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality).  相似文献   

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