Se-containing spirulina phycocyanin attenuated liver injury induced by carbon tetrachloride in mice

AIM:To investigate the effect of Se-containing spirulina phycocyanin (Se-SPC) on liver injury of mice induced by carbon tetrachloride (CCl₄). METHODS:The mouse model was conducted by intragastric feeding with 2% CCl₄ oil for three times, meanwhile Se-SPC, spirulina phycocyanin (SPC) and Na₂SeO₃ were injected (ip) to various groups for 7 days. Then selenium (Se), glutathione peroxidase (GPx), superoxide dismutase (SOD), alanine aminotransferase (ALT), malondiaoldehyde (MDA) and nitric oxide (NO) levels in blood and liver were measured. RESULTS:The level of Se,GPx and SOD activities were obviously higher(P<0.05)but ALT activity,MDA and NO₂^-/NO₃^- levels were remarkably lower(P<0.05)in Se-SPC treated groups than those in CCl₄ groups,and effects of high dose Se-SPC on Se,GPx,MDA and NO₂^-/NO₃^- were even more significant(P<0.01).Under the same dose of Se or protein,effects of all selected targets in Se-SPC groups were more efficient than those in SPC groups and inorganic-Se groups.Furthermore,Se levels had a positive correlation with GPx activity(r=01705),which had negative correlation with levels of MDA,NO₂^-/NO₃^- and ALT(r=-0.629,r=-0.336,r=-0.457,respectively), and positive correlations between ALT activity and MDA or NO₂^-/NO₃^- level were found (r=0.519,r=0.641). CONCLUSION:These results indicated that Se-SPC may attenuate liver injury of mice induced by CCl₄ through its anti-inflammatory action and enhancing selenoenzyme expression.     

硒胁迫对紫花苜蓿硒积累及矿质元素吸收的效应

为了探讨硒胁迫对紫花苜蓿硒积累及对其他矿质元素吸收的影响。以3种苜蓿阿尔冈金、大叶苜蓿、维多利亚为试材,采用土培试验方法,研究了硒胁迫对紫花苜蓿不同组织的生物量、转运系数、耐性指数、硒积累量、硒含量和矿质元素含量的影响及紫花苜蓿对硒的积累能力。结果表明:施以100μmol/L硒时,硒处理显著提高了3个品种苜蓿根、茎、叶片的硒含量、耐性指数、硒积累量和K、P、Ca、Mg元素的吸收,当硒浓度为900μmol/L时,则降低了阿尔冈金和维多利亚不同器官生物量及大叶苜蓿根的生物量积累,且降低了阿尔冈金和维多利亚不同器官及大叶苜蓿根和茎对Zn吸收积累量。不同品种间相比较,大叶苜蓿生物量、硒积累量和K、P、Mg元素吸收显著高于其他2个苜蓿,且差异显著。综合评价表明,大叶苜蓿对矿质元素和Se有较好的吸收和富集能力。     

硒的生物学特性与奶牛营养需要的研究进展

对硒的生物学特性,硒对奶牛健康的影响以及奶牛对硒的需要量作了比较全面的综述,为奶牛饲养过程提供科学的参考依据。     

硒对硒蛋白-谷胱甘肽过氧化物酶基因表达及其酶活性的调节

本文根据国内外研究现状详细综述了硒调节细胞型谷胱甘肽过氧化物酶(GPX1)mRNA水平、蛋白水平及酶活3个水平的可能分子机理,初步概述硒对其余GPX基因表达的影响及其作用机制,为深入研究硒调节GPX基因表达的作用机制提供参考。     

Comparative responses to sodium selenite and organic selenium supplements in Belgian Blue cows and calves

Belgian Blue (BB) beef cattle is particularly prone to selenium (Se) deficiency due to the poor Se content of soil and roughages on rearing farms and the higher requirements of this hypermuscled breed. The goal of this trial was to compare the effects of different forms and concentrations of Se supplementation on Se status, health and performance in 60 pregnant Se-deficient BB cows. Cows were allocated to 3 experimental groups receiving selenized-yeast at 0.5 ppm Se on total ration (Y–Se 0.5), Na–selenite at 0.5 ppm Se on total ration (Na–Se 0.5) and Na–selenite at 0.1 ppm Se on total ration (Na–Se 0.1), respectively. Cows were supplemented from 2 months before calving until 2 months after calving. Data on performance, health and Se status of the dams and their calves were analyzed using a linear model, least squares means and logistic regression. At the end of the study, plasmatic Se (pSe) was significantly higher (P < 0.01) in cows receiving Y–Se than in cows from other groups. Glutathion-peroxidase in erythrocytes (GSH-pxe) was higher in Y–Se and Na–Se 0.5 than Na–Se 0.1 group (P < 0.01). Se content in colostrum and milk was significantly higher (P < 0.01) in Y–Se than other groups. At birth, Se status of calves from group Y–Se was significantly higher than those of other groups (P < 0.01). Plasmatic Se in calves remained higher for 75 days after birth in Y–Se compared to other groups (P < 0.01). Diarrhoea was the most commonly observed disease in the calves and, during the first 15 days of life, diarrhoea occurred in 6%, 21% and 35% of calves from groups Y–Se, Na–Se 0.5 and Na–Se 0.1, respectively. Over the whole 75 days trial period, incidence of diarrhoea was 19, 29 and 65%, respectively. Average daily gain (ADG) in calves born from Y–Se group of cows tended to be higher than in Na–Se 0.5 (P = 0.06) and Na–Se 0.1 (P < 0.05) but there was no difference between Na–Se 0.5 and Na–Se 0.1 (P > 0.1). At the same dosage, Y–Se conferred better Se status in both dams and their calves than did Na–Se. Requirement of 0.1 ppm Se seems to be insufficient in BB to optimise health and performance. Regarding health status and ADG in calves, Y–Se seems also to result in better performance.     

海南番木瓜主产区土壤、植株硒含量及施硒效应研究

海南番木瓜土壤及植株硒含量的调查结果表明：海南主产区的番木瓜果园土壤普遍处于较低硒含量状态。采用叶面喷施并配合土施硒肥的方法，可以明显提高番木瓜植株及果实中的硒含量。     

Information technology and innovative drainage management practices for selenium load reduction from irrigated agriculture to provide stakeholder assurances and meet contaminant mass loading policy objectives

Many perceive the implementation of environmental regulatory policy, especially concerning non-point source pollution from irrigated agriculture, as being less efficient in the United States than in many other countries. This is partly a result of the stakeholder involvement process but is also a reflection of the inability to make effective use of Environmental Decision Support Systems (EDSS) to facilitate technical information exchange with stakeholders and to provide a forum for innovative ideas for controlling non-point source pollutant loading. This paper describes one of the success stories where a standardized Environmental Protection Agency (EPA) methodology was modified to better suit regulation of a trace element in agricultural subsurface drainage and information technology was developed to help guide stakeholders, provide assurances to the public and encourage innovation while improving compliance with State water quality objectives. The geographic focus of the paper is the western San Joaquin Valley where, in 1985, evapo-concentration of selenium in agricultural subsurface drainage water, diverted into large ponds within a federal wildlife refuge, caused teratogenecity in waterfowl embryos and in other sensitive wildlife species. The fallout from this environmental disaster was a concerted attempt by State and Federal water agencies to regulate non-point source loads of the trace element selenium. The complexity of selenium hydrogeochemistry, the difficulty and expense of selenium concentration monitoring and political discord between agricultural and environmental interests created challenges to the regulation process. Innovative policy and institutional constructs, supported by environmental monitoring and the web-based data management and dissemination systems, provided essential decision support, created opportunities for adaptive management and ultimately contributed to project success. The paper provides a retrospective on the contentious planning process and offers suggestions as to how the technical and institutional issues could have been resolved faster through early adoption of some of the core principles of sound EDSS design.     

富硒纳豆芽孢杆菌的选育试验

利用纳豆芽孢杆菌将无机硒生物转化为有机硒后,进行富硒纳豆的发酵试验.结果表明:纳豆芽孢杆菌能够进行无机硒的生物转化,其转化无机硒的最大浓度为1.0×10-6mol/L.过量的无机硒对纳豆芽孢杆菌具有明显的毒害作用,少量的无机硒可促进纳豆芽孢杆菌的生长.通过正交试验优化出富硒纳豆的最佳发酵条件为1 kg大豆中添加硒1.0×10-6mol,接种量7%,培养温度42℃,培养时间18 h,经检测此条件下发酵的纳豆硒含量为6.58μmol/kg,无机硒的转化率达73.6%.     

青海河卡牧场硒的季节变化及盈缺分析

试验研究了青海共和盆地河卡牧场夏、冬两季牧草草地系统(水、土壤、牧草、绵羊)中硒的含量变化.结果表明,河卡牧场夏季土壤和牧草严重缺硒,绵羊血浆中硒浓度低于临界水平,夏冬两季绵羊被毛中硒含量低于毛硒含量临界值.     

The Effect of Consumption of Selenium Enriched Rye/Wheat Sourdough Bread on the Body’s Selenium Status

The potential of selenium-enriched rye/wheat sourdough bread as a route for supplementing dietary selenium intakes is reported. In addition to their normal diets, 24 female volunteers (24 to 25 years old) were fed either selenium-enriched bread or non-enriched bread each day (68.02 and 0.84 μg selenium day⁻¹ respectively) for 4 weeks. The chemical form of the selenium in the bread had been characterised using HPLC-ICP-MS, which showed that 42% of the extractable selenium was present as selenomethionine. Plasma selenium levels and plasma platelet glutathione peroxidase (GPx1) activity were measured in the volunteers’ blood over a 6-week period. A statistically significant difference (p = 0.001) was observed in the mean percentage change data, calculated from the plasma selenium level measurements for the enriched and control group, over the duration of the study. A comparable difference was not observed for the platelet GPx1 activity (p = 0.756), over the same period. Two weeks after cessation of the feeding stage, i.e., at t = 6 weeks, the mean percentage change value for the selenium plasma levels in the enriched group was still significantly elevated, suggesting that the absorbed selenium had been incorporated into the body’s selenium reserves, and was then being slowly released back into the volunteers’ blood.