河豚毒素中毒机制和防治的研究进展

河豚毒素(TTX)是一种强神经毒素。它的化学结构、作用机理、中毒防治方法以及在医学和化工上应用受到关注，成为海洋生物资源研究开发的重要课题。本文综述了近年来有关河豚毒素的化学结构、中毒机制、检测技术、中毒防治等方面的最新研究进展，并提出了河豚毒素研究要突变的科技问题以及制备高纯度河豚毒素在医学上作为抗肿瘤、抗神经痛等高效制剂。     

水产品中河豚毒素检测技术研究进展

河豚毒素是河豚鱼及其他生物体内含有的一种内源性生物碱, 是自然界中所发现的毒性最大的神经毒素之一, 被认为是自然界中毒性最强的非蛋白类毒素。自从2016年9月有条件放开养殖红鳍东方鲀和养殖暗纹东方鲀加工经营后, 水产品中河豚毒素含量的准确测定, 已经受到了越来越多的关注。本文综述了水产品中河豚毒素含量色谱、质谱检测技术的最新研究进展, 着重总结了样品前处理技术和分析检测技术, 并对各种样品前处理技术和检测技术的优缺点进行了探讨。     

织纹螺中河豚毒素限量研究

目的提出织纹螺中河豚毒素的限量建议值,为日常监控提供判定依据。方法对织纹螺中河豚毒素的来源、含量情况、毒性、检测标准以及国内外有关河豚毒素、麻痹性贝类毒素的规定等文献资料进行分析比较,探讨织纹螺中河豚毒素的限量要求。结果织纹螺可分为有毒织纹螺、无毒织纹螺、季节性有毒织纹螺,织纹螺中河豚毒素的浓度范围为0～177 mg/kg,而且河豚毒素毒性是麻痹性贝类毒素的30倍以上(以两者对小鼠的经口LD50比较)。对光织纹螺、正织纹螺等常年带毒且毒素含量高的有毒织纹螺应有效识别并禁止采捕、销售、食用,建议无毒织纹螺和季节性有毒织纹螺中河豚毒素的限量为0.05 mg/kg,测定方法采用GB/T 23217—2008《水产品中河豚毒素的测定》。结论提出织纹螺中河豚毒素的限量建议值应合理可行,有效地完善了织纹螺中河豚毒素的监控体系,保障广大公众的身体健康与生命安全。     

河豚毒素抗血清的制备与纯化

研究中利用甲醛作为交联剂,将河豚毒素(Tetrodotoxin,TTX)与匙孔槭血兰蛋白(Keyhole limpethemocyanin,KLH)连接起来作为免疫抗原免疫新西兰大白兔,以牛血清白蛋白(Bovine serum albumin,BSA)与河豚毒素的交联物作为包被抗原,成功的制备了兔抗河豚毒素抗血清,并用DEAE-纤维素柱将抗血清进行了纯化.     

河豚毒素DNA适配子的筛选与结构分析

人工合成113个碱基的随机ssDNA文库,以河豚毒素为靶物质,采用SELEX技术进行12轮筛选,测定各轮富集文库与河豚毒素的亲和力,其中第10轮富集文库与河豚毒素的亲和力最高。将第10轮富集文库进行克隆、测序,用DNAMAN软件分析克隆子的一级和二级结构,并测定克隆子与河豚毒素的亲和力。结果表明:与河豚毒素结合力高的DNA适配子经过10轮筛选后得到富集,成功筛选到最高亲和力的DNA适配子G10。     

养殖河豚鱼的加工及河豚毒素消减技术研究概述

河豚鱼肉质鲜嫩,味道鲜美,享誉古今中外。我国东南沿海地区、日本等许多国家和地区均有吃河豚的习惯,但河豚鱼的内脏、表皮、卵巢等部位含有河豚毒素,因食用河豚鱼导致的中毒事件时有发生。因此,有效消减控制河豚毒素对河豚鱼产业发展有重要意义。该文主要介绍了我国河豚鱼食用历史和消费现状,对养殖河豚鱼深加工制品种类做详细阐述,重点探讨了河豚毒素消减方法和消减机理的研究情况,以期对河豚毒素的消减控制提供参考。     

河豚毒素快速检测技术在养殖河豚鱼 监管中的应用

河豚毒素(tetrodotoxin,TTX)是一种分子量约为319的含氮生物碱,具有极高的毒性,食用河豚毒素含量高的河豚鱼易发生中毒事件。TTX含量的多少因河豚鱼的种类、部位及季节等而有差异,TTX主要集中于河豚的卵巢和肝脏,且在卵巢孕育阶段毒性最强,河豚鱼肉(皮)、精囊无毒。日、韩等国对河豚鱼消费实行科学分类管理,严格区分了"可食用"和"不可食用"的河豚鱼品种、部位等。我国对河豚鱼一直实行"禁食"管理;然而,我国河豚鱼产业却处于"禁食而不禁养"状况,且在国内已形成了较大的"灰色"消费市场。本文梳理了近年来TTX的快速检测技术发展现状,并对快速检测技术在养殖河豚鱼监管中的应用发展前景进行探讨,以期为从事食品安全监管及快速检测技术研究工作的人员提供参考。     

超高效液相色谱-串联质谱法测定闽东地区织纹螺中河豚毒素

建立了快速检测闽东地区织纹螺中河豚毒素含量的高效液相色谱-串联质谱方法。织纹螺均质样品用1%乙酸水溶液提取,0.5%乙酸甲醇溶液稀释,冷冻10min后离心除蛋白,亲水作用色谱柱分离,乙腈-0.1%甲酸水溶液作为流动相梯度洗脱,UPLC-MS/MS分析。基质匹配标准曲线外标法定量。方法的检出限为10μg/kg,定量限为25μg/kg,满足欧洲食品安全委员会对双壳贝类和腹足类中河豚毒素安全限量值44μg/kg的检测要求。在织纹螺中添加50、100、250μg/kg 河豚毒素进行加标回收试验,河豚毒素回收率为79.6%~118.1%,相对标准偏差为(RSD,n=6)7.7%~10.6%。采用该方法测定闽东地区14份织纹螺样品,最高检出河豚毒素 25718.2μg/kg。该研究方法准确性高、成本低、操作性强,能够满足当前快速定量检测织纹螺中河豚毒素含量的技术要求。     

假睛东方鲀肝脏中河豚毒素的分离纯化

本文主要研究分子层析柱对河鲀鱼肝脏中河豚毒素分离纯化效果,为河豚毒素分离纯化工艺提供参考。本实验以假睛东方鲀肝脏为原料,对肝脏中的TTX进行提取,然后利用柱层析技术,确定了中性氧化铝柱、活性炭柱、CM HF和D152弱酸性阳离子交换树脂柱的上样液最适pH、吸附率、回收率。并根据四种柱子的吸附率和净化回收率的结果综合评定,其中D152弱酸性阳离子交换柱吸附率和回收率分别为91.97%和93.98%,且该柱子纯化河豚毒素的效果好,损失率低,最后得到产物多,因此选择D152柱作为分离纯化河豚毒素粗提液纯化柱。最后以假睛东方鲀肝脏为原料,将肝脏匀浆得到的粗提液经D152柱纯化分离后,结晶析出得到河豚毒素粗品,纯度为80%。此研究为河豚毒素分离纯化工艺提供有益参考。     

河豚毒素DNA适配子核心区域的识别

用DNA folding form在线软件分析河豚毒素DNA适配子A3、G10的二级结构,根据二级结构,分别合成适配子A3、G10的各4个区域的5’端地高辛标记的序列。用丙烯酸-环氧乙烷珠子固定河豚毒素,测定抗地高辛碱性磷酸酶的适宜稀释倍数,用地高辛-抗地高辛碱性磷酸酶系统检测各区域与河豚毒素的亲和力,识别出适配子的核心区域。结果表明,抗地高辛碱性磷酸酶的适宜工作浓度为2×104倍稀释;合成的适配子A3的4个区域中,A3-2区域与河豚毒素的亲和力最强,即适配子A3的核心区域为A3-2区域,实际上含有47个核苷酸;合成的适配子G10的4个区域中,G10-4区域与河豚毒素的亲和力最强,即适配子G10的核心区域为G10-4区域,实际上含有56个核苷酸。     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.     

Analysis for organic residues from aids to polymerization used to make plastics intended for food contact

Polymers intended for food contact use have been analysed for organic residues which could be attributed to a range of substances employed as polymerization aids (e.g. initiators and catalysts). A wide range of polymers was extracted with solvents and the extracts analysed by gas chromatography-mass spectrometry (GC-MS). The overwhelming majority of substances identified were not derived from aids to polymerization but were oligomers, additives and adventitious contaminants. However, a small number of substances were identified as initiator residues. These included tetramethylsuccinonitrile (TMSN) which was observed in two polymers and it derived from recombination of two azobisisobutyronitrile (AIBN) initiator radicals. Methyl benzoate, benzoic acid, biphenyl and phenyl benzoate were detected in one poly(methyl methacrylate) sample and in two polyvinylchlorides and they are thought to be derived from benzoyl peroxide initiator. TMSN was subsequently targeted for analysis of poly-(methyl methacrylate) plastics using proton nuclear magnetic resonance spectrometry (¹     

Tests of potential functional barriers for laminated multilayer food packages. Part II: Medium molecular weight permeants

Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. I: Interlaboratory studies of methods of analysis

This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four postcolumn derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.     

The Ministry of Environmental Protection Issued "Feasible Technology Guidelines for Pollution Prevention and Control in Wood Pulping Process of the Paper Industry (Trial)" and Two Other Guiding Technical Documents

On December 27t＂, 2013, the Ministry of Environmenta Protection announced that, in order to implement ＂The Environmental Protection Law of the People＇ s Republic of China＂, improve the working system in environmenta protection technologies, and promote technologica advancement in pollution prevention, the Ministry of Environmental Protection sponsored the formulation of three guiding technical documents including ＂Feasible Technology Guidelines for Pollution Prevention and Contro n Wood Pulping Process of the Paper Industry （Trial）＂     

1~(st) Intelli-Tissue~ EcoEc Tissue Machine Supplied by PMP Group Successfully Put into Operation in China

正On April 29th,2014,Intelli-Tissue EcoEc tissue machine supplied by PMP Group successfully put into operation at Hebei Xuesong Paper Co.,Ltd.,this is the first such kind of paper machine of PMP Group in China.