In this study the molecular formula and structure of lipid constituents of silver carp and bighead carp in middle reaches of Yangtze River were determined by gas chromatography-mass spectrometry. The position of doubl...In this study the molecular formula and structure of lipid constituents of silver carp and bighead carp in middle reaches of Yangtze River were determined by gas chromatography-mass spectrometry. The position of double bounds was identified by the method of double bounds chemical localization. These carps are proved to contain eicosapantaenoic acid (EPA) and decosahexenoic acid (DHA). The contents of EPA and DHA, which were determined by gas chromatography, in silver carp and bighead carp were approximately the same as in tuna and salmon. The contents of EPA and DHA in 100 g wet sample were 0. 187 g, 0. 229 g and 0. 246 g, 0. 325 g respectively, but the cholesterol contents in silver carp and bighead carp were much lower than in tuna and salmon.展开更多
为研究大黄鱼(Larimichthys crocea)蛋白质在海水流化冰辅助保鲜期内的变化,采用串联质谱标签(tandem mass tag,TMT)技术定量标记新鲜(贮藏0 d)大黄鱼及不同海水流化冰贮藏时间(7、23 d)下大黄鱼的肌肉蛋白质,筛选出不同贮藏时间下的差...为研究大黄鱼(Larimichthys crocea)蛋白质在海水流化冰辅助保鲜期内的变化,采用串联质谱标签(tandem mass tag,TMT)技术定量标记新鲜(贮藏0 d)大黄鱼及不同海水流化冰贮藏时间(7、23 d)下大黄鱼的肌肉蛋白质,筛选出不同贮藏时间下的差异表达蛋白,并对差异蛋白进行基因本体(gene ontology,GO)、直系同源簇/真核生物直系同源簇(clusters of orthologous groups/clusters of eukaryotic orthologous groups,COG/KOG)与京都基因和基因组数据库(Kyoto Encyclopedia of Genes and Genomes,KEGG)分析。结果显示,在3个比较组(7 d vs 0 d、23 d vs 7 d和23 d vs 0 d)中鉴定到的差异蛋白总数分别为215、133、269个,其中表达上调的差异蛋白数分别为117、37、113个,表达下调的差异蛋白数分别为98、96、156个。同时,3个比较组的共有差异蛋白为44个。GO分析表明,差异蛋白主要参与细胞过程、生物调节、细胞和细胞内组分、结合功能和催化活性等方面;COG/KOG分析表明,差异蛋白的功能活性主要集中在细胞骨架、碳水化合物转运和代谢、信号转导机制以及翻译后修饰、蛋白质周转和伴侣蛋白等方面;KEGG分析表明,差异蛋白共参与38条信号通路,且在贮藏后期(23 d),紧密连接和致病性大肠埃希菌感染2条信号通路中差异蛋白的参与数目最多,它们可能是造成大黄鱼新鲜度急剧下降的主要信号通路。44个共有差异蛋白与大黄鱼新鲜度指标进行的相关性分析表明,脆性X智力低下综合征相关蛋白2、肌醇-1-单磷酸酶、Rho GDP解离抑制剂1、锚蛋白-1和甲基四氢叶酸合酶结构域蛋白可以作为新鲜度指示蛋白。本研究为揭示大黄鱼在海水流化冰贮藏期内的品质变化机制、大黄鱼新鲜度评价和保鲜工艺改进提供了依据。展开更多
文摘目的建立柱前衍生高效液相色谱-串联质谱法(high performance liquid chromatography-tandem mass spectrometry,HPLC-MS/MS)测定鲜茶叶中春雷霉素的检测方法。方法样品经甲醇/水溶液提取,MCX SPE阳离子交换柱(mixed-mode cation exchanger SPE column)净化,9-氯甲酸芴甲酯[9-fluorenylmethyloxycarbonyl(Fmoc)chloride,Fmoc-Cl]衍生后测定,内标法定量。结果目标化合物在0.31~20.00μg/L范围内,线性关系良好,相关系数大于0.998(r^(2))。鲜茶叶中春雷霉素的检出限(limit of detection,LOD)、定量限(limit of quantification,LOQ)分别为2.0μg/kg和5.0μg/kg。在LOQ、2×LOQ和10×LOQ水平上加标,平均回收率为95.2%~104.0%,相对标准偏差为7.4%~13.3%。结论基于Fmoc-Cl衍生化的测定法,能有效提高检测的灵敏度、降低基质的干扰;将西马特罗作为内标使用,可以提供更为准确的检测结果,该方法满足鲜茶叶中春雷霉素的监测。
文摘In this study the molecular formula and structure of lipid constituents of silver carp and bighead carp in middle reaches of Yangtze River were determined by gas chromatography-mass spectrometry. The position of double bounds was identified by the method of double bounds chemical localization. These carps are proved to contain eicosapantaenoic acid (EPA) and decosahexenoic acid (DHA). The contents of EPA and DHA, which were determined by gas chromatography, in silver carp and bighead carp were approximately the same as in tuna and salmon. The contents of EPA and DHA in 100 g wet sample were 0. 187 g, 0. 229 g and 0. 246 g, 0. 325 g respectively, but the cholesterol contents in silver carp and bighead carp were much lower than in tuna and salmon.
文摘为研究大黄鱼(Larimichthys crocea)蛋白质在海水流化冰辅助保鲜期内的变化,采用串联质谱标签(tandem mass tag,TMT)技术定量标记新鲜(贮藏0 d)大黄鱼及不同海水流化冰贮藏时间(7、23 d)下大黄鱼的肌肉蛋白质,筛选出不同贮藏时间下的差异表达蛋白,并对差异蛋白进行基因本体(gene ontology,GO)、直系同源簇/真核生物直系同源簇(clusters of orthologous groups/clusters of eukaryotic orthologous groups,COG/KOG)与京都基因和基因组数据库(Kyoto Encyclopedia of Genes and Genomes,KEGG)分析。结果显示,在3个比较组(7 d vs 0 d、23 d vs 7 d和23 d vs 0 d)中鉴定到的差异蛋白总数分别为215、133、269个,其中表达上调的差异蛋白数分别为117、37、113个,表达下调的差异蛋白数分别为98、96、156个。同时,3个比较组的共有差异蛋白为44个。GO分析表明,差异蛋白主要参与细胞过程、生物调节、细胞和细胞内组分、结合功能和催化活性等方面;COG/KOG分析表明,差异蛋白的功能活性主要集中在细胞骨架、碳水化合物转运和代谢、信号转导机制以及翻译后修饰、蛋白质周转和伴侣蛋白等方面;KEGG分析表明,差异蛋白共参与38条信号通路,且在贮藏后期(23 d),紧密连接和致病性大肠埃希菌感染2条信号通路中差异蛋白的参与数目最多,它们可能是造成大黄鱼新鲜度急剧下降的主要信号通路。44个共有差异蛋白与大黄鱼新鲜度指标进行的相关性分析表明,脆性X智力低下综合征相关蛋白2、肌醇-1-单磷酸酶、Rho GDP解离抑制剂1、锚蛋白-1和甲基四氢叶酸合酶结构域蛋白可以作为新鲜度指示蛋白。本研究为揭示大黄鱼在海水流化冰贮藏期内的品质变化机制、大黄鱼新鲜度评价和保鲜工艺改进提供了依据。