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双语推荐:硒形态

形态与其功能和毒性关系密切,基于环境样品的复杂性在形态分析中选择合适的预处理是硒形态分析准确性的前提。目前硒形态分析预处理的方法主要有:液相萃取、微波辅助萃取、固相微萃取以及液相微萃取,笔者简单分析了各种预处理方法的原理、特点,综述了各种预处理及形态分析方法的应用条件、优缺点,展望了元素形态分析上的应用情景。
Seleniumforms are related to its function and toxicity, to choose the appropriate preprocessing is the precondition of seleniumspeciation analysis accuracy due to the complexity of environmental samples in the morphological analysis.The pretreatment methods in seleniumspeciation analysis mainly include the liquid phase extraction,microw ave assisted extraction,solid phase microextraction and liquid phase microextraction. This paper simply analyses the principles and characteristics of every pretreatment method, applications of all pretreatmentand morphologicalmethods,theiradvantagesand disadvantages,and prospectsthe application ofelementspeciation analysis.

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目的研究转基因大豆对的富集作用以及富集前后转基因大豆中形态分布和形态转化。方法 采用电感耦合等离子体质谱分析转基因大豆富集前后的总量,采用蛋白酶提取,高效液相色谱-电感耦合等离子体质谱(high performance liquid chromatography-inductively coupled plasma-mass spectrometry,HPLC-ICP-MS)联用技术分析转基因大豆中的酸盐(selenate,Se VI)、亚酸盐(selenite,Se IV)、代蛋氨酸(selenomethionine,Se Met)和代胱氨酸(selenocystine,Se Cys)等几种化合物。盆栽种植试验研究转基因大豆对的富集作用。通过对照试验,考察大豆植株不同部位总含量变化和形态分布的转化情况。结果转基因大豆对有较好的富集作用,吸收的亚酸盐在大豆植株中部分转化成了代蛋氨酸和代胱氨酸。结论 了解了转基因大豆的形态分布和转化情况,可以更好地评估转基因大豆的食用安全风险并进行生物利用开发。
Objective Tostudy the selenium enrichment of genetically modified soybean, selenium com-pound species distribution and transformation before and after enrichment.MethodsThe total selenium con-tent in genetically modified soybean were detected by inductively coupled plasma-mass spectrometry. Ex-tracted with protease, selenium species of selenate [Se(VI)], selenite [Se(IV)], selenomethionine (SeMet) and selenocystine (SeCys) in genetically modified soybean were detected using high performance liquid chromato-graphy-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). The changes of total selenium content in different parts of the soybean plant and distribution of transformation of selenium species based on the con-trast test, which were made by potted planting, were also studied.Results The genetically modified soybean had a better enrichment on selenium, with the selenite uptaken by soybean plant partly being converted into se-lenomethionine and selenocystine. Conclusio
建立了富酵母中酸Se(Ⅵ)、亚酸Se(Ⅵ)、代蛋氨酸(SeMet)和甲基代半胱氨酸(SeMeCys)4种硒形态的高效液相色谱-氢化物发生原子荧光光谱(HPLC-HG-AFS)分析方法。样品采用蛋白酶和胰蛋白酶酶解提取,20 mmol/L(NH4)2HPO4为流动相,经PRP-X100阴离子交换色谱柱分离后HG-AFS测定。结果显示,4种硒形态标准曲线的线性关系良好(R^2≥0.9995),方法检出限为0.5~5.0μg/kg,平均回收率为82.5%~101.2%,日内相对标准偏差≤8.6%,日间相对标准偏差≤14.5%。本方法前处理简单、灵敏度高、设备便宜、运行费用低廉,适用于富饲料产品中形态分析。
A rapid and sensitive method has been developed for the simultaneous determination of four selenium species Se(Ⅵ), Se(Ⅵ), selenomethionine, and Se-methylselenocysteine in Se-enriched yeast by liquid chromatography-hydride generation atomic fluorescence spectrometry (HPLC-HG-AFS). The isolation of the analytes from yeast samples was accomplished by proteaseⅩⅣ and trypsin enzymatic digestion. The target compounds were separated on a PRP-X100 anion exchange column and analyzed by HG-AFS. The mobile phase was 20 mmol/L (NH4)2HPO4. Good linearity was obtained for all the selenium species, with linear correlation coefficients higher than 0. 9996. The LODs of the four species were between 0. 5 and 5. 0 μg/kg. Average recoveries for the four analytes were in the ranges of 82 . 5%-101 . 2%, with intra-and inter-day RSD lower than 8. 6% and 14. 5, respectively. The proposed analytical method is simple, sensitive, with low operation cost, making it applicable for the determination

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阐述了植物对不同形态硒的吸收、转运和形态转化机制。植物主要吸收水溶性,包括部分有机酸盐和亚酸盐。多数研究表明植物对酸盐的主动吸收是通过高亲和力的硫酸盐转运子完成,最近的研究表明磷酸盐可以调节亚酸盐的吸收,磷酸盐转运子在亚酸盐的主动吸收过程中有重要作用;植物吸收的酸盐很快从根部转移到地上部,在叶片中被还原成亚酸盐,进而转化为有机化物进入其他组织;而亚酸盐及其代谢产物主要积累在根部,极少转移到地上部。进入植物体中的转化为含氨基酸和蛋白参与植物的代谢。
In this review, we summarized the uptake, translocation and metabolism mechanisms of selenium(Se)in plants. Water-soluble Se, including selenate, selenite and some organic selenium, was the predominant form taken up by plants. The active uptake of selenate in plant could be mediated by high affinity sulfate transporters. The mechanism of selenite uptake was not well understood, however, recent studies suggested that selenite uptake was probably mediated by Pi transporters. The translocation of Se from root to shoot was dependent on the form of Se supplied. The selenate taken up by plants was readily translocated to the shoots and reduced to selenite in leaves, then convert-ed to organic Se compound. By contrast, most of the selenite taken up by plants in the roots and only a small fraction was translocated to the shoots. Se could be assimilated to seleno amino acids or selenoprotein after plant uptake, and then involved in the metabolism of plants.

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土壤的丰缺与人类和动物的健康密切相关,依据李家熙的土壤含量划分标准,石头河地区存在中土壤(0.2~0.4×10-6)和富土壤(〉0.4×10-6)。小麦籽实分析均为富小麦,与富土壤关系密切。硒形态分析表明土壤中的强/弱有机结合态、水溶态、残渣态、铁锰结合态、碳酸盐结合态含量变化均为:水稻土〉水系沉积物〉褐土。的全量及形态含量受pH值影响较大,在酸性土壤中施加一定量的CaCO3,可提高土壤的pH值,增加的溶解度,有利于提高植物对土壤的吸收。
The abundance and deficiency of soil selenium is closely related to the health of human being and animals.According to the classification definition standard of soil selenium amount put forward by Li Jiaxi,it is confirmed that there exist selenium-rich soil (0.2~0.4×10-6 ) and selenium-moderate soil (>0.4×10-6 ) in Shitou River area.The analytical results of wheat seeds show that the Se a-mount is up to the standard of selenium-rich wheat.A study of the modality of Se in the soil shows that the Se content change of stream sediments and cinnamon soil,water soluble state,residue,Fe-Mn oxides and carbonate-bound selenium is in order of paddy soil>stream sediment >cinnamon soil.Soil pH value has a great impact on the amount of ion exchange state selenium,and the addition of a certain mount of CaCO3 can improve pH value in acid soil and is in favor of increasing the solubility of selenium.

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该文对国内外富相关标准进行了梳理,从标准中的检测技术发展、不同方法间的异同,以及每一种检测原理的灵敏度、准确度和精密度等方面对的检测方法标准进行了动态追踪和系统分析,同时对富产品标准中覆盖的产品范围、不同产品的含量要求和其他主要技术要素进行了比较归纳,最后结合我国富产业的发展实际提出了硒形态分析检测的必要性和制定相关检测方法标准,以及在产品标准中增加硒形态要求技术要素的合理化建议,这对规范我国富产品的检测和富产品标准的科学化制定具有重要的指导和借鉴意义。
The paper compares and analyzes the Chinese and foreign standards for selenium-rich products. In these standards, the development and difference of Se detecting techniques including the sensitivity, accuracy and precision are all traced dynamically and analyzed systemically. Meanwhile, the range of the Selenium-rich products, the limiting value of Se and other key technical factors are compared and analyzed. Considering the recent development of selenium-enriched industry in China, the paper proposes suggestions on the necessity of Se speciation detection and development of related detection and testing standards, providing references for the detection of selenium-rich products and development of selenium-rich product standards.

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是人体和动物所必需的一种微量元素。茶叶作为一种优质的来源,对人体的摄入有着重要意义。本文主要从的重要性,土壤中的含量、形态和分布,茶叶中的含量以及影响茶叶积累的因素等4个方面进行了总结。此外还对富茶今后的研究方向进行了展望,以期为开发富茶提供参考依据。
Selenium is an essential trace element for human body and animal. Tea, as a kind of high-quality selenium source, was great significant to the intake of selenium in human body. The four aspects were summarized in the paper such as the importance of selenium, the content, morphology and distribution of selenium in soil, the selenium content in tea and the effect of selenium accumulation in tea. In addition, the future research directions of Se enriched tea were forecasted in the paper so as to provide references for the development of Se enriched tea.

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目的采用高压液相色谱-氢化物发生-原子荧光光谱联用技术(HPLC-HG-AFS)对水产品中的赋存形态检测进行研究。方法通过实验优化流动相、提取剂、提取时间及其仪器条件,建立HPLC-HG-AFS联用技术检测水产品中硒形态的分析方法。用去离子水在70℃水浴下超声提取1 h,流动相为pH 6.0的40mmol/L(NH4)2HPO4溶液,阴离子交换柱分离,HG-AFS检测。结果样品加标量在0.10、1.00 mg/kg时的回收率均在86.6%以上,相对标准偏差均小于5%。结论本研究证明使用该方法测定水产品中的硒形态较为准确、可靠,为科学评价水产品质量、进一步细化富水产品的判定标准和鉴别其真伪提供技术手段,为科学有效地开展其风险评估提供技术支撑和数据支持。
Objective The determination of selenium speciation in aquatic products by high performance liquid chromatography-hydride generation-atomic fluorescence spectrometry (HPLC-HG-AFS) was analyzed in this study. Methods The mobile phases, extraction reagents, extraction time and instrumental conditions were optimized and then selenium speciation in aquatic products was analyzed by HPLC-HG-AFS. Samples were extracted at 70℃for 1 h by ultrasonic extraction and the flow phase was 40 mmol/L (NH4)2HPO4 (pH6.0). The different selenium speciation was separated with anion exchange column and detected by HG-AFS. ResultsThe average recoveries of 0.10 mg/kg and 1.00 mg/kg in samples were all above 86.6%and the relative stan-dard deviations were all below 5% with a high accuracy. Conclusion The established method was accurate and reliable for selenium speciation analysis. It could provide technological support for scientific evaluation of the aquatic product quality, as well as the authenticity of the

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采用高效液相色谱法(HPLC)分离水中两种常见形态Se(Ⅳ),Se(Ⅵ),通过电感耦合等离子体质谱系统进行检测鉴定,由此建立了水中硒形态的分析方法。以0.15 mmol/L EDTA(钾)–0.1 mmol/L四丁基氢氧化铵–0.15 mmol/L乙酸铵–5%甲醇为流动相,调节流动相pH值至6~7,两种不同形态可在4 min内得到有效分离。测定Se(Ⅳ),Se(Ⅵ),的线性范围为2~100μg/L,线性相关系数(r2)不低于0.999,Se(Ⅳ)和Se(Ⅵ)的检出限分别为0.01,0.05μg/L。分别以水源水、管网水等为基体进行加标回收试验,Se(Ⅳ)和Se(Ⅵ),的回收率分别为102.3%~106.2%,104.7%~108.3%,测定结果的相对标准偏差分别为6.4%~9.6%,4.4%~7.3%(n=5)。该方法灵敏度高,具有良好的精密度和准确度,可用于环境水体中元素硒形态分析。
The method for determination of different species of selenium in water samples by high performance liquid chromatography (HPLC)–inductively coupled plasma mass spectrometry (ICP–MS) was established. The results showed that Se( Ⅳ ) and Se( Ⅵ ) could be separated within 4 min by using 0.15 mmol/L EDTA–K,0.1 mmol/L tetrabutyl ammonium hydroxide(TBAOH),0.15 mmol/L ammonium acetate and 5%methanol as mobile phase under pH 6–7. The detection linear range of Se(Ⅳ) and Se(Ⅵ) was 2–100μg/L with correlation coefficient (r2) of 0.999. The detection limits of Se( Ⅳ ) and Se( Ⅵ ) were 0.01, 0.05μg/L, the recoveries were 102.3%–106.2%,104.7%–108.3%, and the relative standard deviations were 6.4%–9.6%,4.4%–7.3%(n=5), respectively. The proposed method shows good accuracy, precision and sensitivity, which can be used for analyzing species of selenium in environment water.

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综合近年来国内外的研究文献,从对植物的生理作用、植物含量和影响因素以及植物硒形态分布和转化等方面进行了系统分析。今后应该继续对在植物体内的作用进行深入分析,结合分子和基因手段以及同位素技术,探索培育富作物品种的可能性以及在生产实践中应用的价值。继续在自然土壤条件下加强富作物生产技术的开发,为合理利用资源提供可持续技术保障。
The paper collected relevant literatures on selenium and explored the function to plant, selenium content, influential factors and selenium specification and transformation. We believed that there should be more deep researches on function of selenium to plant. Ap-proaches of molecular, genetic engineering and isotope could be employed to breed selenium rich crops and possibilities in practice. More ef-forts should be spent on the technologies research for improving selenium level in crops under natural soil conditions to sustainably utilize the selenium resources.

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