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1.
昆明系小鼠生物法定量测定水产品中河豚毒素   总被引:2,自引:0,他引:2  
为建立昆明系小鼠定量测定河豚毒素(TTX)方法,选用体质量19~21g的昆明系小鼠作为实验对象,用不同质量浓度TTX溶液腹腔注射小鼠。结果显示:TTX致昆明系小鼠的半数致死量(LD50)为0.18μg,小鼠死亡时间与TTX注射剂量满足方程Y=e(0.357/X+1.005)。此外,采用体积分数0.5%乙酸溶液提取TTX,回收率达到90%以上,对样品的最低检测限为0.56μg/g。昆明系小鼠定量测定河豚毒素,准确、稳定、方便快捷,可用于水产品安全检测。  相似文献   

2.
目的建立了一种河豚中河豚毒素(TTX)的高效液相色谱-串联质谱检测方法。方法取适量样品,在0.03 mol/L乙酸溶液中均质后超声提取样品中的河豚毒素。粗提液低速离心,取上清液加入等量甲醇充分混匀后进行高速离心。高速离心后上清液过0.22μm滤膜后待测。采用Waters ACQUITY UPLC BEH Amide(2.1mm×100 mm,1.7μm)色谱分析柱,含0.1%甲酸的Milli Q水及乙腈溶液为流动相,电喷雾正离子模式进行分析。结果河豚毒素在5~1000 ng/m L的范围内线性关系良好,相对回收率为83.3%~93.2%,绝对回收率为47.8%~48.9%,检出限为5μg/kg,定量限为2 0μg/kg。结论 与以往检测TTX的LC-MS/MS方法相比,新建方法操作简单、快速、准确、灵敏并且实验成本低,为河豚中TTX的定量检测提供了有效的实用技术手段。  相似文献   

3.
河豚毒素直接竞争ELISA检测方法的研究   总被引:10,自引:1,他引:9  
本研究应用直接竞争ELISA法对河豚毒素(tetrodotoxin,ITX)进行快速检测.用过碘酸钠氧化法合成酶标记抗原HRP-OVA-TTX),用直接ELISA方法对合成的酶标记抗原进行鉴定表明其与抗TTX单克隆抗体具有特异性反应.在此基础上建立了包被单抗的直接竞争ELISA方法.该方法对TTX的检测限可达到1.1μg/L,IC50为20.4μg/L,线性范围3.3~137μg/L,批内变异系数小于6.25%,批间变异系数小于7.34%.对鲫鱼的肌肉组织添加TTX标准品,回收率为65%~93.2%,变异系数为9.41%~12.77%.  相似文献   

4.
高效液相色谱-串联质谱法检测河豚毒素的 方法研究   总被引:1,自引:1,他引:0  
目的 创新性地建立了一种用高效液相色谱-串联质谱法检测水产品中的河豚毒素的方法。方法 取适量样品,在0.03M乙酸溶液中均质后超声提取样品中的河豚毒素。粗提液低速离心,取上清液加入等量甲醇充分混匀后进行高速离心。高速离心后上清液过0.22μm滤膜后待测。采用Waters ACQUITY UPLC BEH Amide(2.1×100mm,1.7μm)色谱分析柱,含0.1%甲酸的MilliQ水及乙腈溶液为流动相,电喷雾正离子模式进行分析。结果 河豚毒素在5-1000 ng/mL的范围内线性关系良好,相对回收率为85.8%~93.2%,绝对回收率为47.8%~48.9%,检出限为0.4ng/mL,定量限为1 ng/mL。 结论 与以往检测TTX的LC-MS/MS方法相比,新建方法操作简单、快速、准确、灵敏并且实验成本低,为水产品中TTX的定量检测提供了有效的实用技术手段。  相似文献   

5.
目的建立高效液相色谱-串联四级杆质谱联用仪多反应监测技术(MRM)测定鱼体中的河豚毒素(TTX)含量的方法。方法海鱼样品用80%酸化甲醇水溶液(含0.1%乙酸)超声提取,二氯甲烷脱脂净化,超滤管离心,取滤液过膜后进行分析。目标物TTX以p H=3.5的乙腈-0.06%甲酸铵溶液(65∶35,V/V)为流动相,经HILIC色谱柱(100 mm×2.1 mm,3μm)等梯度洗脱分离,采用电喷雾离子源,选择质谱多反应监测正离子模式,以保留时间和河豚毒素的二级质谱特征碎片离子予以双定性确证,基质标准曲线校正,外标法定量。结果河豚毒素与杂质能良好分离,在0.10~2.0 mg/kg范围内线性关系良好(r=0.997),方法检出限为0.012 mg/kg,定量限为0.041 mg/kg,加标回收率为75.7%~108.1%,相对标准偏差为1.4%~5.1%。应用该方法对20份实际样品进行检测,均未检出TTX。结论本方法准确、快捷、简便,可应用于食物中毒因子识别与鉴定。  相似文献   

6.
邵碧英  陈彬  陈文炳  杨方  缪婷玉  彭娟 《食品科学》2014,35(24):205-208
人工合成78个碱基的随机ss DNA文库,采用指数富集配基的系统进化技术与诱变聚合酶链式反应(polymerase chain reaction)结合的方法,通过筛选富集、克隆、测序,获得了与河豚毒素(tetrodotoxin,TTX)特异结合的单克隆DNA适配子A3。DNA适配子A3的二级结构主要为茎环结构,与TTX的亲和力为1.254。对适配子和TTX结合的磷酸盐缓冲液p H值、荧光染料结合时间进行优化,结果表明,最适p H值为7.5,最佳结合时间为10 min。建立的快速筛选检测TTX的DNA适配子-荧光染料法对TTX的检出限为10-6 mo1/L。  相似文献   

7.
目的:选择血蓝蛋白(KLH)和牛血清白蛋白(BSA)分别作为载体蛋白与河豚毒素(TTX)进行偶联制备人工抗原,并对合成结果进行鉴定。方法:通过甲醛法将TTX分别与大分子载体蛋白,即血蓝蛋白(KLH)和牛血清白蛋白(BSA)进行偶联。利用紫外扫描法、电泳法对偶联产物进行鉴定,并对6周龄Balb/c雌性小鼠免疫注射检测其免疫原性。结果:紫外扫描显示偶联抗原较载体蛋白有轻微的红移现象出现,且经过琼脂糖凝胶及SDS-PAGE 2种方法电泳检测后发现,载体蛋白较人工抗原之间迁移率均不相同;对免疫小鼠进行间接酶联免疫吸附试验(iELISA)及间接竞争酶联免疫吸附试验(icELISA)联用检测其多抗血清效价及特异性,经过共计6次免疫后的效价能达到1:40w,且能有效抑制TTX。结论:河豚毒素人工抗原制备成功且具备良好的免疫原性。  相似文献   

8.
建立了快速检测闽东地区织纹螺中河豚毒素含量的高效液相色谱-串联质谱方法。织纹螺均质样品用1%乙酸水溶液提取,0.5%乙酸甲醇溶液稀释,冷冻10min后离心除蛋白,亲水作用色谱柱分离,乙腈-0.1%甲酸水溶液作为流动相梯度洗脱,UPLC-MS/MS分析。基质匹配标准曲线外标法定量。方法的检出限为10μg/kg,定量限为25μg/kg,满足欧洲食品安全委员会对双壳贝类和腹足类中河豚毒素安全限量值44μg/kg的检测要求。在织纹螺中添加50、100、250μg/kg 河豚毒素进行加标回收试验,河豚毒素回收率为79.6%~118.1%,相对标准偏差为(RSD,n=6)7.7%~10.6%。采用该方法测定闽东地区14份织纹螺样品,最高检出河豚毒素 25718.2μg/kg。该研究方法准确性高、成本低、操作性强,能够满足当前快速定量检测织纹螺中河豚毒素含量的技术要求。  相似文献   

9.
为了研究河豚毒素(TTX)在暗纹东方鲀体内的转移分布规律及其对肝脏代谢酶活性的影响,实验选择口服灌喂的给药方式,通过超高效液相色谱串联质谱法测定不同组织中TTX的浓度变化,同时测定肝脏代谢酶活力。结果如下,在灌喂TTX后的短期转移分布期间,性腺中TTX的浓度从19.00 ng/g升至42.02 ng/g,蓄积率为121%。肝脏中TTX浓度呈波动性变化,在4 h时,TTX浓度最高为11.43 ng/g,在48 h时,TTX浓度最低为1.27 ng/mL。皮肤、肌肉、血液、肠道、鳃组织中TTX含量在2 h时最高,分别为7.43 ng/g、1.15 ng/g、11.44 ng/g、9.77 ng/g、31.75 ng/g。脾脏、肾脏、胆组织中TTX浓度分别在2 h、4 h、6 h时最高为5.05 ng/g、6.54 ng/g、9.06 ng/g。此外,肝脏代谢酶活力的检测结果显示,TTX显著提高了乳酸脱氢酶、谷草转氨酶和谷丙转氨酶的活性(p0.05),在前期对两种磷酸酶活性具有明显的抑制效应(p0.05),而后恢复至正常水平。实验结果表明,TTX在暗纹东方鲀中的转移分布具有组织特异性,并且对肝脏中不同代谢酶活性具有促进和抑制作用。  相似文献   

10.
对低次烟叶分别进行高温高水分好氧和厌氧发酵,烘干,陈化一周后制备提取液,应用顶空固相微萃取气质联用HS-SPME-GC-MS对不同提取液中的挥发性致香成分进行分析比较,并将浓缩后提取液涂布于片基上进行评吸。结果表明,经高温高水分好氧和厌氧发酵低次烟叶制备的提取液中挥发性致香成分种类分别为52种、51种,合计质量浓度分别为43.38μg/m L、40.16μg/m L。而未经发酵低次烟叶制备的提取液中挥发性致香成分种类为34种,合计质量浓度为23.61μg/m L;低次烟叶经固态发酵后所得提取液中酸类、酯类、酮类、醇类、醛类、杂环类等致香成分均有不同程度的增加,増香除杂效果明显,能够改善烟草薄片的吸食品质。  相似文献   

11.
Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.  相似文献   

12.
An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.  相似文献   

13.
The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.  相似文献   

14.
The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.  相似文献   

15.
A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.  相似文献   

16.
Capillary electrophoresis (CE) and polarized light microscopy (PLM) were utilized in the detection of the adulteration of locust bean gum with guar gum. For CE analyses, standards of locust bean and guar gums were extracted with 30% CH3CN, removing the residual proteins from the gum matrix. A 8.75 mM NaH2PO4-20.6 mM Na2B4O7 buffer, pH 9, was used to separate these proteins and to identify marker proteins that were present in the guar gum. These markers did not co-migrate with components in the extracts of mechanically processed locust bean gum, and are used as indicators of adulteration. Using PLM with toluidine blue and iodine staining techniques, unadulterated locust bean gum samples were distinguished from mixed samples through the differential staining of components in locust bean versus guar and tara gums. These experiments in the use of CE and PLM provide orthogonal and complementary methods for the verification of 'true' positives and the elimination of 'false' positives.  相似文献   

17.
18.
BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H2O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.  相似文献   

19.
An investigation is described in which various polyfunctional compounds were applied to wool in attempts to stabilize the temporary improvements in wrinkle-recovery brought about by ‘annealing’. Several reactive systems involving formaldehyde were found to produce the desired permanently improved wrinkle-recovery.  相似文献   

20.
《造纸信息》2014,(8):79-79
Ministr y of Industr y and Information Technology confirmed that the main expected targets for energysaving and comprehensive utilization in 2014 are:energy consumption and CO2 emissions per unit of industrial added-value decreases by 4.5%,water consumption per ten thousand Yuan of industrial added-value decreases by7%,comprehensive utilization of industrial solid waste is further improved,and pollution emissions in key industries is markedly reduced.  相似文献   

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