东洞庭湖鲢鱼和鳙鱼中重金属富集差异分析

为分析东洞庭湖水体中重金属污染情况以及鲢鳙鱼间重金属富集存在的差异性,测定东洞庭湖沉积物以及鲢鱼和鳙鱼不同组织中5种重金属(Cr、Cu、Cd、Pb和Hg)的含量。结果显示,沉积物中Cr的含量低于国家一级土壤标准限值,Cu、Pb和Hg低于二级土壤标准限值,Cd的含量是国家三级土壤环境标准值的6倍;鲢鱼和鳙鱼中重金属的分布排序均为Cr:鳃肝脑肉,Cu:肝脑鳃肉,Cd:肝鳃脑肉,Pb:鳃肝肉脑,Hg:肉肝脑鳃;根据鱼类的生物-沉积物富集因子,相比Cr和Pb,鲢鱼和鳙鱼都更易富集Cu、Cd和Hg,而鲢鱼比鳙鱼更易富集Cd,鳙鱼比鲢鱼更易富集Hg;另外,鲢鱼和鳙鱼肝脏中Cd的含量超出行业标准限量,其它组织中重金属均未超标。表明东洞庭湖中Cd的污染最为严重;不同鱼类对重金属的富集确实存在差异性,不同组织对同一重金属的富集能力也存在显著差异;相比较鱼鳃和肝脏,鱼肉和鱼脑对重金属的亲和能力较弱。     

水产品中三种常见重金属污染物的毒性及风险评估进展

我国是水产品养殖和消费大国,重金属污染是水产品安全面临的主要问题之一。含重金属的工业废水经河流排放到水域水体中,并且在水底的沉积物中沉积,造成养殖环境污染。而后经过食物链富集到生物体内,对水生生物本体和食用受污染水产品的人类都会引起健康问题。本文综述了近几年水域水体和沉积物中的重金属污染研究现状,并对污染严重的Cd、As、Pb三种重金属的毒性进行了概括,最后总结了现今对水产品风险评估的主要方法和研究现状。通过本文所引用文献分析,对比水体中的重金属污染,沉积物中的污染程度较大,多具有中等生态风险,故对水产品重金属污染影响较大。重金属对人体和水产品均有很强的毒性作用,根据众多风险评估研究结果表明,水产品重金属超标的情况仍较普遍,单因子污染指数和风险熵指数绝大多数小于1,无潜在健康风险,但依然存在高复合性污染的情况。     

水体沉积物重金属污染分析方法研究

水体沉积物是河流和湖泊污染物的重要载体,对水体沉积物中重金属污染的分析可以了解水体的污染程度,污染物的扩散范围并对污染物来源进行追述,在水体环境分析中具有重要作用。文章对现行常用的水体沉积物重金属污染分析方法进行了研究和讨论,分析了各种分析方法的优缺点以及适用范围,并对如何提高分析的科学性和准确性提出了建议。     

大米中镉元素的快速测定

<正>镉(Cd)是自然界中存在的一种重金属元素,其并非人体所必需的元素之一。人体内的镉均是出生后从外界环境中吸取的,主要通过食物、水和空气进入人体而蓄积下来。而食物、水和空气中的镉则主要来自于采矿、冶炼行业、工业废水、废气以及化肥等对于土壤、水体和大气的污染。镉及其化合物均有一定的毒性,受污染的土地上长出的作物会含有一定量的镉,这些镉通过食物链进入人体,可在人体内蓄积。当体内镉含量达到一定浓度之后,会引起肾脏、     

湛江湾牡蛎养殖区沉积物重金属含量分布与潜在生态危害评价

本研究于2010年1月(冬季)、4月(春季)、7月(夏季)、11月(秋季)分别对湛江湾海域官渡养殖区(S1)、南油养殖区(S2)、特呈岛养殖区(S3)和东头山岛养殖区(S4)的沉积物重金属含量进行调查,且对养殖区进行重金属污染程度和潜在生态危害评价。结果如下:四个养殖区沉积物中重金属的含量均较低,除特呈岛养殖区Cr的含量属于第二类沉积物质量标准外,其他养殖区的Cr和另外五种重金属含量均达沉积物质量第一类标准,根据Hakanson潜在生态危害指数法对该海域沉积物中重金属进行评价,该海域沉积物重金属的综合效应不具有潜在生态危害。     

基于最优最劣和熵值法的肉制品中重金属污染程度综合评价模型

提出一种基于最优最劣和熵值法的肉制品中重金属污染综合评价模型,该方法首先从毒性、含量2个方面构建评价体系,然后用最优最劣法评价各类肉制品的重金属污染程度,用熵值法对各地区肉制品中重金属污染程度进行综合评价。以某省5个城市4类肉制品重金属检测数据为例进行案例研究,对4类肉制品重金属污染程度排序发现,按内梅罗指数法和超标率两种评价方法计算的结果分别为熟肉干制品>腌腊肉制品>酱卤肉制品>熏煮香肠火腿制品和腌腊肉制品>酱卤肉制品>熟肉干制品>熏煮香肠火腿制品;而用文中综合评价方法计算的结果为酱卤肉制品>腌腊肉制品>熟肉干制品>熏煮香肠火腿制品。对5市肉制品重金属污染程度进行排序发现,按内梅罗指数法和超标率两种评价方法进行计算的结果均为A市>C市>B市>E市>D市,与文中方法的排序结果一致。对比方法和文中综合评价方法排序结果既有联系又有差异,造成差异的原因是对比方法考虑因素单一,而文中所提模型能较全面客观反映重金属污染情况,并可以有效突出不同地区重金属污染程度的差距。     

电镀废水中铬的污染控制化学原理和方法

本文从生态效应的角度介绍了电镀行业废水中重金属铬在环境中的迁移、转化规律,以及铬污染对人体健康及水生生物等其他生物的影响、对水体自净作用的影响。并述了水中铬污染治理的研究进展,提出了未来含铬废水治理的发展方向。     

覆膜栽培对烤烟重金属含量的影响

为探讨烤烟重金属的调控措施,采用大田试验,在重金属Cd,Pb,Hg和Cr复合污染土壤的条件下,研究了覆膜与不覆膜处理对土壤和烤烟中重金属含量的影响。结果表明:覆膜土壤的过氧化物酶、脱氢酶、酸性磷酸酶和脲酶的活性均低于不覆膜;不覆膜处理对下部叶和中部叶重金属治理效果较好;覆膜处理对上部叶重金属的治理效果较好;覆膜处理的烟根干重显著高于不覆膜处理;覆膜后烟根对Cd的吸收能力增强,Hg向腋芽中的迁移量与烟根对Hg的吸收能力均降低,Cr向烟茎中的迁移量与烟根吸收Cr的能力降低;覆膜和不覆膜处理重金属Cd,Pb和Hg在腋芽中积累均较多。因此,可通过调控腋芽量来减少重金属在烟叶中的积累量。     

台州近岸海域水质、沉积物和贝类体内镉含量的初步调查

2009年10月至2014年8月对台州近岸海域贝类养殖区的水质、泥质及贝类自身体内的重金属镉含量进行监测,并根据《渔业水质标准》(GB11607-1989)以及《海水水质标准》(GB 3097-1997)(II类),对水质进行评价,结果表明水质中重金属镉含量均低于标准值5ug/L,适合养殖;根据《海洋沉积物质量》(GB 18668-2002)(第一类),沉积物中重金属镉含量均低于标准值5mg/kg;根据《食品安全国家标准食品中污染物限量》(GB2762-2012),对泥蚶、缢蛏体内重金属镉的污染程度进行评价,结果表明蛤、缢蛏、贻贝均没有超标,泥蚶的超标情况相对比较严重。     

蘑菇湖水库水体重金属污染情况分析与评价

为了分析蘑菇湖水库水体重金属含量的影响,通过野外采样和室内测定,分析了Pb、Cu、Zn和Cd的含量,利用单因子指数法和内梅罗指数法对其污染状况进行了评价。结果表明,水体中Pb含量已经非常接近国家地表水环境质量Ⅳ标准的检测限,而其余的重金属含量远低于Ⅳ标准,水体中重金属在不同区域的变化趋势也表明Pb污染的隐患。因此,我们应该密切关注蘑菇湖水库Pb含量的变化及加强污染源管理。     

Probiotics and prebiotics--perspectives and challenges

Owing to their health benefits, probiotics and prebiotics are nowadays widely used in yogurts and fermented milks, which are leader products of functional foods worldwide. The world market for functional foods has grown rapidly in the last three decades, with an estimated size in 2003 of ca US$ 33 billion, while the European market estimation exceeded US$ 2 billion in the same year. However, the production of probiotics and prebiotics at industrial scale faces several challenges, including the search for economical and abundant raw materials for prebiotic production, the low-cost production of probiotics and the improvement of probiotic viability after storage or during the manufacturing process of the functional food. In this review, functional foods based on probiotics and prebiotics are introduced as a key biotechnological field with tremendous potential for innovation. A concise state of the art addressing the fundamentals and challenges for the development of new probiotic- and prebiotic-based foods is presented, the niches for future research being clearly identified and discussed.     

常用消毒灭菌法及其机理与应用

介绍了采用消毒灭菌方法,有加热消毒法,紫外线辐射法和化学药剂消毒法。常用化学药剂有醛类、含氯消毒剂、醇类消毒剂以及高锰酸钾、生石灰等,阐释了消毒与灭菌两个概念的区别。     

European citizen and consumer attitudes and preferences regarding beef and pork

This paper presents the combined mid-term findings of the consumer research components of two EU Sixth Framework Programme integrated projects concerning meat, ProSafeBeef and Q-PorkChains. The consumer pillar of ProSafeBeef carried out eight focus group discussions in May 2008, in France, Germany, Spain and the UK. Q-PorkChains conducted a large-scale, web-based, consumer survey in January 2008 in Belgium, Denmark, Germany, Greece and Poland. The first project provides a set of qualitative data from a small cohort of focus groups and the second a set of quantitative data from a larger consumer sample. This paper draws together the main findings of both projects and provides a comprehensive overview of European citizens’ and consumers’ attitudes towards and preferences regarding beef and pork. In general, consumers consider meat to be a healthy and important component of the diet. Consumers support the development of technologies that can improve the health attributes of meat products and guarantee eating quality, but they have a negative view of what they see to be excessive manipulation and lack of naturalness in the production and processing of beef products. In the Q-PorkChains study consumer and citizen segments are identified and profiled. Consumer segments were built upon the frequency and variety of pork consumption. The citizen segments were built upon their attitudes towards pig production systems. Overall, the relationship between individuals’ views as citizens and their behaviour as consumers was found to be quite weak and did not appear to greatly or systematically influence meat-buying habits. Future studies in both projects will concentrate on consumers’ acceptance of innovative meat product concepts and products, with the aim of boosting consumer trust and invigorating the European beef and pork industries.     

毛霉型低盐速成豆豉工业化生产工艺与设备

本文介绍了毛霉型低盐速成豆豉的工业化生产工艺及生产线的关键设备。     

原花色素及其开发应用

对原花色素的结构、化学特性、制备、分析方法、应用前景作一综述,并重点讨论其生理功能,为在功能性食品、药物、化妆品等领域的深入研究和开发提供参考。     

组学技术与果蔬采后质量和安全控制

果蔬可以提供营养, 有利于人类健康, 而果蔬的后熟及其与环境的相互作用会影响果蔬采后的质量和安全。对果蔬生物学过程的了解和掌握是减少果蔬采后损失和保障果蔬采后质量和安全的关键。在过去的10多年, 基于组学技术的系统生物学在了解果蔬后熟及其与环境相互作用的分子机制方面得到了越来越多的应用。本文对此做了细致的总结, 指出了存在的不足, 并提出了未来的发展方向。     

天然香精香料与生物技术

天然香精香料是高价值的精细化工产品和食品添加剂,但原料来源有限且提取成本高。利用生物技术生产这类产品具有广阔的前景。简述了发酵工程、酶工程、细胞工程和基因工程在香精香料中的应用,并探讨了生物技术在香精香料中的应用前景。     

益生素、益生菌与结肠癌

介绍了益生素和益生菌及其作用机理。在动物模型中，有大量的数据证实益生素和益生菌能够预防癌症．而在人体内还没有直接实验证据。它们抑制癌症的确切机理目前尚不清楚，其抑制机理可能是：肠道菌群代谢活动的改变，肠道理化环境的改变，潜在的致癌物质的黏附和降解，肠道菌群的改变、抗癌或抗诱变物质的形成、提高宿主的免疫应答、影响宿主的生理活动以及发酵不能被消化的食物并形成有益代谢产物。     

节能节水型印染助剂和设备的现状

从节能、节水、缩短工艺流程和环保的角度出发,介绍了国内外研制开发的一系列新型节能、节水型印染助剂和染整设备。     

Heritability and correlations for body condition score and dairy form within and across lactation and age

The objectives of the current study were to investigate the relationship between body condition score (BCS) and dairy form and changes in genetic parameters for BCS and dairy form within and across lactations and age. Body condition score and dairy form were obtained from the Holstein Association USA, Inc. Records were edited to include those cows classified between 24 and 60 mo of age and between 0 and 335 d in milk (DIM). A minimum of 20 daughters per sire and 15 cows per herd-classification visit were required. The dataset consisted of 135,178 records from 119,215 cows. Repeatability, multiple trait, and random regression models were used to analyze the data. All models included fixed effects for herd-classification visit, age within lactations 1, 2, and 3 or higher, and 5th-order polynomials for DIM. Random effects included sire and permanent environment for all models. Random regression models included age at classification nested within sire or DIM and lactation number nested within sire. Genetic variance for both BCS and dairy form was lowest in early lactation and highest in midlactation. Genetic correlations within and across lactations were high. The genetic correlation between DIM 0 in lactation 1 and DIM 305 in lactation 3 was estimated to be 0.77 for BCS and 0.60 for dairy form. The genetic correlation estimate between 30 mo of age at classification and 50 mo of age at classification was 0.94 for both dairy form and BCS. The repeatability models appeared to generate accurate evaluations for BCS or dairy form at all ages and stages of lactation.