太平洋牡蛎对无机硒的富集作用研究

在海水中添加亚硒酸钠(Na2SeO3),研究活体太平洋牡蛎(Pacific Oyster)对硒的富集作用,通过测定牡蛎不同部位的有机硒与无机硒含量,探讨硒在牡蛎体内的分布及转化问题.结果表明,天然牡蛎体内的硒含量为(0.638±0.079)μg(鲜重),在Na2SeO3质量浓度为15 μg/mL的海水中养殖3 d后,牡蛎体内的硒含量为(4.049±0.340)μg,总硒、无机硒和有机硒的富硒倍率分别为6.4倍、3.7倍和8.4倍,说明富集到牡蛎体内的以有机硒为主;牡蛎在养殖3 d后,各部位的硒含量均有不同程度的上升,有机硒的上升速率大于无机硒,说明牡蛎各部位都具有较强的富集无机硒的能力,并且可以通过自身代谢将无机硒转化为有机硒.     

3种淡水鱼肉中Ca、Fe、Cu、Zn含量测定

采用原子吸收光谱仪对鲫、鲢、草鱼肌肉中Ca、Fe、Cu、Zn元素含量进行测量.样品用干法灰化和湿法消解.结果表明3种淡水鱼肉中微量元素含量丰富,其中草鱼中Ca含量高,鲢中Cu含量高,鲫中Fe含量高.Ca的加标回收率95%～108%,相对标准偏差RSD＜5.0%;Fe的加标回收率92%～109%,RSD＜2.4%;Zn的加标回收率94%～111%,RSD＜1.1%;Cu的加标回收率109%～113%,RSD＜2.4%.     

渔业水质中尿素检测方法的研究

建立了一种检测渔业水质中尿素的方法。方法检出限为0.031mg/L,当尿素含量在0.1～5.0mg/L范围时，标准曲线线性关系良好，r=0.9992。分别测定高、中、低3个浓度的加标样品，回收率为86.0～109.0%,相对标准偏差为0.9～2.9%,加标回收和精密度均符合要求。该方法简单、灵敏、干扰少、准确度高，线性范围广，能满足对渔业水质中尿素的检测要求。     

微波消解-氢化物原子荧光光度法测定牡蛎中汞

探索微波消解-氢化物原子荧光光度法测定牡蛎中的汞,选择最佳微波消解条件和原子荧光测定条件对牡蛎中的汞进行微波消解前处理和上机测定,相关系数达到0.9997,线性方程为If=156.9141*C+2.3118,线性范围为0～1.6μg/L,方法检出限为0.0412μg/kg,仪器检出限为0.0914μg/kg。加标回收率为92.5%-130.1%,RSD为0.007,测定标准物质GBW 08573中汞的含量均在不确定度范围内,其平均值为0.167 mg/kg,在设定的微波消解条件下,提取牡蛎中Hg准确度和精密度较高。     

3种淡水鱼肉中Ca、Te、Cu、Ze含量测定

采用原子吸收光谱仪对鲫、鲢、草鱼肌肉中Ca、Fe、Cu、Zn元素含量进行测量。样品用干法灰化和湿法消解。结果表明3种淡水鱼肉中微量元素含量丰富，其中草鱼中Ca含量高，鲢中cu含量高，鲫中Fe含量高。ca的加标回收率95％～108％，相对标准偏差RSD〈5．0％；Fe的加标回收率92％～109％，RSD〈2．4％；Zn的加标回收率94％-111％，RSD〈1．1％；Cu的加标回收率109％～113％，RSD〈2．4％。     

气相色谱法同时测定海水中13种拟除虫菊酯类杀虫剂的残留量

建立了海水中13种拟除虫菊酯类杀虫剂的气相色谱检测分析方法。海水样品用二氯甲烷提取,经Florisil固相萃取柱净化,使用配有电子捕获检测器(ECD)的气相色谱仪测定,外标法定量。13种目标物在2.5～100.0μg/L质量浓度范围内线性良好,相关系数均大于0.995,检出限均为5.0 ng/L,定量限均为10.0 ng/L,加标回收率为76.6%～107.1%,相对标准偏差(RSD)为3.9%～12.7%。本方法稳定、可靠,适用于海水中13种拟除虫菊酯类杀虫剂的同时测定,可为海水质量监测提供技术支持。     

液相色谱-串联质谱法测定贝类毒素软骨藻酸的残留

建立了液相色谱-串联质谱测定贝类毒素软骨藻酸残留的检测方法。样品经50%甲醇提取，LC-SAX柱净化，然后选用电喷雾离子源（ESI），在正离子、多反应监测方式（MRM）模式下进行定性，以外标法进行定量。方法的定量限为0.10μg/g，工作曲线的线性范围为0.10μg/g～8.00μg/g。在添加浓度为0.10μg/g～4.00μg/g的范围内，软骨藻酸的平均回收率范围为79.8%~92.2%，RSD范围为4.90%~9.46%。     

氢化物(Hydride)--原子荧光光谱法(Atomic Fluorescence Speebrophotometry)测定海洋沉积物中的痕量硒(Trace Selenium)

本文采用硝酸一高氯酸处理样品，研究了氢化物原子荧光光谱法测定海洋沉积物中痕量硒的方法。在选定的试验条件下，方法检出限为0．15μg／kg；进行了大量的海洋沉积物样品测定，相对标准偏差为0．42％～5、41％，加标回收率为81．70％～98．38％，结果满意。方法具有操作简便、快速、灵敏度高等优点。     

酶联免疫法快速检测水产品中硝基呋喃类代谢物、氯霉素及氟苯尼考

应用特异性强的间接酶联免疫法,同时检测4种硝基呋喃类代谢物、氯霉素(CAP)和氟苯尼考(FF),建立快速分析水产品中6种药物残留量的方法。样品用盐酸进行消化,再由乙酸乙酯提取,使用酶联免疫试剂盒进行检测。实验结果显示,6种分析物均在其线性范围内,线性系数均大于0.995。在加标浓度为0.1、0.5和1.5μg/kg的加标水平下,组织样中CAP的加标回收率为60.00%~126.26%;在加标浓度为0.5、2.0和8.0μg/kg的加标水平下,组织样中FF的加标回收率为60.83%~68.37%;在加标浓度为0.1、0.5和2.0μg/kg的加标水平下,组织样中呋喃西林代谢物(SEM)的加标回收率为65.66%~148.16%;在加标浓度为0.2、1.0和4.0μg/kg的加标水平下,组织样中呋喃它酮代谢物(AMOZ)的加标回收率为69.18%~140.50%;在加标浓度为0.2、1.0和4.0μg/kg的加标水平下,组织样中呋喃妥因代谢物(AHD)的加标回收率为62.50%~131.00%;在加标水平为0.1、0.5和2.0μg/kg的加标水平下,组织样中呋喃唑酮代谢物(AOZ)的加标回收率为83.1%~144.0%。研究结果说明6种分析物的相对标准偏差均在0~7.5%之间,本方法灵敏度高、快速简便,适用于水产品中硝基呋喃类代谢物、氯霉素和氟苯尼考的快速批量检测。     

用流动注射分光光度法测定水中的六价铬含量

2016年5、9和10月,在东经121°37′46″和北纬40°58′56″采样,用流动注射分光光度法监测辽宁大凌河水中六价铬的含量。结果表明:在酸性样品中,六价铬与二笨卡巴肼形成紫红色络合物,最大吸收峰在550nm处。本方法的线性范围为0.02~0.50mg/L(r0.999),检出限为0.0022mg/L,在0.05mg/L和0.50mg/L的相对标准偏差(RSD)为0.8%和0.5%,相对误差为0.0%和0.2%,加标回收率为98.8%~100.9%,测定速率为30样/h。本方法操作简单,溶剂数量少,干扰因素少,人工误差小,分析效率高,灵敏度高,准确度高,稳定性好。     

分光光度法测定水产品中甲醛含量的研究

研究采用乙酰丙酮分光光度法测定水产品中的甲醛含量，对样品的前处理过程进行了比较系统的探讨，确定了比色测定参数，并对其用于快速测定水产品中甲醛含量的可行性进行了讨论。实验结果表明，用冰浴浸泡法前处理样品时，最佳浸泡时间为10min，样液pH值用100g·L^-1氢氧化钾溶液调至6；沸水浴中最佳显色时间为3min，比色波长为412nm；当甲醛含量在0～2．5μg·mL^-1范围内时，该方法具有很好的线性关系（R^2=0．9998）；与蒸馏法前处理样品相比，该方法的加标回收率比较高，在89．50％～94．25％之间，而前者为64．17％～76．92％；该方法的RSD（％）为2．93％，样品的最低检出浓度为0．9mg·kg^-1。     

Rapid and sensitive determination of furaltadone metabolite 3-amino-5-morpholinomethyl-2-oxazolidinone by biotin–streptavidin-amplified time-resolved fluoroimmunoassay

A competitive time-resolved fluoroimmunoassay (TRFIA) using a biotin–streptavidin system was developed for the detection and quantification of the furaltadone metabolite 3-amino-5-morpholinomethyl-2-oxazolidinone (AMOZ) in aquatic tissues. AMOZ-bovine serum albumin was coated to a solid phase and then competed with a free nitrophenyl derivative of AMOZ (2-NP-AMOZ) in standards or samples for binding with biotin-anti-AMOZ-ovalbumin polyantibody. Later, the complex was recognized by europium-labelled streptavidin, which was used as a novel tracer to amplify the signal, and it also reacted faster than europium-labelled second antibody in traditional TRFIA. After optimizing the reaction conditions, the method showed high sensitivity and specification to 2-NP-AMOZ with a half maximal inhibitory concentration of 0.190 μg/l and a sensitivity of 0.019 μg/l with a working range from 0.025 to 10 μg/l. The data from fish and shrimp samples indicated that the limit of detection was 0.021 μg/kg, and the recovery rates were 84.1–107.0% and 80.9–98.4%, respectively, with an average RSD below 10%. High correlation rates were observed in TRFIA, high performance liquid chromatography and universal enzyme-linked immunosorbent assay methods. The experiment above confirms that biotin–streptavidin-amplified TRFIA could be an ultrasensitive and accurate tool for screening large numbers of aquatic products for the determination of AMOZ residues.     

低鱼粉饲料中添加羟基蛋氨酸硒对凡纳滨对虾生长性能、抗氧化能力和抗亚硝酸盐胁迫的影响

[目的]本实验旨在研究低鱼粉饲料 中添加羟基蛋氨酸硒(HMSe)对凡纳滨对虾(Litopenaeus vannamei)生长性能、抗氧化能力及抗亚硝酸盐胁迫的影响。[方法]实验选用初始体质量为(0.90±0.05)g的凡纳滨对虾,分别投喂HMSe添加水平为0.000、0.375、0.750、1.500和2.250 mg/kg的实验饲料,命名为HMSe0 、HMSe1、HMSe2、HMSe3和HMSe4,每组3个重复,养殖8周。养殖实验结束后,进行12 h 的亚硝酸盐胁迫实验。[结果]结果表明,凡纳滨对虾的终末体质量(FBW)、增重率(WG R)和饲料效率(FE)随着饲料中HMSe水平的增加呈现先升高后下降的趋势,并在HMSe2组达到峰值。随着饲料中HMSe水平的提高,对虾全体和肌肉中的硒含量均显著增加,而全虾粗蛋白和粗脂肪的含量呈现先升高后降低的趋势,并分别在HMSe2组和HMSe1组达到最大值。HMSe4组中凡纳滨对虾的血清谷胱甘肽过氧化物酶(GSH-Px)和肝胰腺过氧化氢酶(CAT)活性显著高于HMSe0组。亚硝酸盐胁迫显著影响凡纳滨对虾的存活率。与胁迫前比较,胁迫后对虾肝胰腺中MDA含量升高,GST、CAT和T-SOD的活性降低,而补充适量的HMSe可减轻这些负面影响。根据凡纳滨对虾胁迫后成活率的二次多项式回归分析,低鱼粉饲料中凡纳滨对虾的HMSe最适添加量为1.350 mg/kg。[结论]综上所述,在低鱼粉饲料中添加0.750~1.350 mg/kg HMSe,能够提高凡纳滨对虾的生长性能、饲料利用率和抗亚硝酸盐胁迫的能力。     

超高效液相色谱串联质谱法对水产品中硝基呋喃代谢物的测定

建立了使用Waters UPLC Xevo TQ超高效液相色谱串联质谱仪检测水产品中4种硝基呋喃代谢物的分析方法。匀浆后的样品在酸性环境下水解,并用2-硝基苯甲醛衍生16h,经磷酸氢二钾提取,LMS固相萃取小柱净化后,在三重四极杆多反应监测模式下进行测定。方法采用同位素内标法定量,四种代谢物的检出限(LOD)均低于0.25μg·kg-1,线性范围在0.5μg·L~(-1)到10μg·L~(-1)间,相关系数大于0.99。在0.5、1.0和5μg·kg-1浓度下分别进行添加回收试验(n=5),回收率在75.2%~123.3%之间,相对标准偏差(RSD)小于9.4%。     

外源硒对仿刺参(Apostichopus japonicus)重要生理相关酶活性及体内硒含量的影响

在水温为16-18℃时,将平均体重为(60.75±0.32)g的仿刺参(Apostichhopus japonicus)饲养在150 cm×120 cm×60 cm的水箱中,通过在基础饲料中添加富硒酵母,使7组饲料中硒的浓度分别为0、0.20、0.40、0.80、1.60、3.20和6.40 mg/kg,进行为期28 d的生长实验,并对其体壁、消化道、呼吸树、肌肉等不同组织消化酶活力、免疫酶活力进行测定,探讨不同水平的外源硒对仿刺参生长、相关酶及体内硒含量的影响,并用氢化物发生-原子荧光光谱法进行仿刺参体内硒含量分析.结果显示,添加适宜浓度的硒提高了仿刺参的成活率(最高达100％)、消化酶和免疫酶的活性,蛋白酶(35.13 U/mg prot)和淀粉酶(0.51 U/mg prot)的最高活性分别为对照组的2.45倍和2.07倍.硒浓度为0.80-1.60 mg/kg时,仿刺参各组中的超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、碱性磷酸酶(AKP)和酸性磷酸酶(ACP)活性最高,显著高于其他组;仿刺参各组中的硒含量均有不同程度的上升,有机硒的提高倍数大于无机硒,说明富集到体内的硒以有机硒为主.研究表明,硒浓度为0.80-1.60 mg/kg时,仿刺参的养殖效果最佳.本研究丰富了仿刺参的营养学内容,为仿刺参健康、高效、可持续养殖提供了一定的参考依据.     

Enrichment of African catfish with functional selenium originating from garlic

We wanted to create functional seafood with high concentrations of organic selenium (seleno-methyl-selenocysteine and γ-glutamyl-seleno-methyl-selenocysteine) with anti-carcinogenic properties for human consumers. Garlic containing high concentrations of these organic selenium compounds was used as a selenium source in five experimental feeds for African catfish (1.9, 2.8, 3.9, 5.1 and 8.5 mg kg⁻¹ Se); a sixth experimental feed was formulated without garlic (1.9 mg kg⁻¹ Se). The experimental feeds were fed to African catfish [initial mean (SD) weight 100.7 (2.7) g] for 43 days with three replicates per treatment. Whole fish fillets were sampled for total selenium analysis (start and end) and selenium speciation (end). We found a positive linear relationship between dietary and fillet concentrations for total selenium and selenomethionine. The dietary total selenium concentration of 8.5 mg kg⁻¹ resulted in a total selenium concentration of 0.9 mg kg⁻¹ in the fillet (wet tissue). The majority of the selenium compounds recovered in an extract made from the fillet consisted of selenomethionine, considered to be important from a nutritional point of view. Seleno-methyl-selenocysteine, one of the organic selenium species to which superior anti-carcinogenic properties are attributed, was detected in the fillet but could not be quantified.     

在线渗析-离子色谱法测定水产品中多聚磷酸盐的研究

文章采用离子色谱法，结合在线渗析技术对水产品中多聚磷酸盐的质量分数进行了测定。该方法测定多聚磷酸盐离子在质量浓度0—10．0mg·L-1线性关系良好，相关系数达到0．999。检出限为3．0～10μg·L-1，回收率为95．8％～104％，连续进样检测值相对标准偏差小于10％。试验结果显示该法分离度好，灵敏度高，检测结果准确，操作方便快速，适合水产品中多聚磷酸盐的测定。     

小龙虾不同部位的无机砷含量分析比较

在6mol/L盐酸水浴条件下,无机砷以氯化物形式被提取,实现无机砷和有机砷的分离,用氢化物发生原子荧光光谱法测定小龙虾不同部位的无机砷含量,检出限为0.05mg/kg,回收率在93.3%～105.2%之间,RSD<5%。检测结果表明,小龙虾无机砷含量具有明显的部位差异,内脏与鳃的含量远高于肌肉中的含量。     

Effect of dietary organic selenium on survival,growth, antioxidation,immunity and gene expressions of selenoproteins in abalone Haliotis discus hannai

No studies have been focused on the inclusion of organic selenium in formulated feed of abalone when organic minerals are accepted by aquaculture feed industry. This experiment evaluated the effect of organic selenium on the growth, antioxidation, immunity and gene expressions of selenoproteins in abalone. Graded levels of organic selenium were included to the basal diet at 0.00, 0.15, 0.30 and 0.60 ppm providing 157.83, 322.51, 437.59 and 596.59 ug/kg of selenium in the diet. Accordingly, the diets were named as Se‐0.00, Se‐0.15, Se‐0.30 and Se‐0.60 respectively. Results had shown that survival rate, weight gain rate and shell length increase rate were lowest for Se‐0.60 group (p < 0.05). The concentration of selenium in the whole body generally increased with increasing level of dietary organic selenium (p < 0.05). The enzyme activities related to antioxidation increased initially with low levels of dietary selenium and decreased with higher levels, with the highest value in Se‐0.30 group (p < 0.05). The enzyme activities of immunity increased with the addition of dietary selenium. With the increase of dietary selenium, Myostain expression decreased initially and increased afterwards, with lowest value for Se‐0.30 group (p < 0.05). However, the expressions of other genes related to growth, antioxidation and selenoproteins firstly increased and then decreased, with the highest value recorded for Se‐0.15 group. In conclusion, the inclusion rate of 0.15 – 0.30 ppm Se in diet could promote growth, antioxidation, immunity and gene expressions of selenoproteins in abalone; however, excess selenium with 0.60 ppm inclusion lever in diet had toxic effects.