不同来源的副溶血性弧菌生物学特性研究

为掌握浙江省不同来源的副溶血性弧菌的血清型分布及毒力基因携带情况，采用血清凝集试验对333株副溶血性弧菌进行血清型分型，采用PCR技术检测副溶血性弧菌的毒力基因TDH。临床副溶血性弧菌菌株血清型分布于7个O抗原群，以O3为主，占临床菌株数的71.81％；04血清型与往年相比有所上升，占到了16．60％。海产品菌株的血清型分布于8个O抗原群，以O5为主，占所有海产品菌株的47．30％。临床菌株的TDH检出率为95．65％。海产品菌株的TDH检出率为6．06％。血清型相同但来源不同的菌株的TDH检出率不同。浙江省从海产品中分离出的副溶血性弧菌菌株与分离自食源性疾病患者的副溶血性弧菌菌株的主要血清型、毒力基因TDH都存在差别。该工作为预防副溶血性弧菌引起的食品中毒提供了科学依据。     

副溶血性弧菌食源性疾病暴发分离株的血清型、核糖型及毒力基因研究

目的 了解目前食源性副溶血性弧菌暴发菌株在上海地区的血清型分布、毒力相关基因的携带情况,及Ribo分型.方法 收集上海市27起食源性副溶血性弧菌暴发事件分离的98株副溶血性弧菌,采用副溶血性弧菌分型血清对所收集的菌株进行血清学分型.利用双重PCR方法扩增tdh,trh两个重要的毒力基因以了解其毒力基因的携带情况.应用Riboprinter系统检测上述菌株的酶切片段杂交多态性.结果 引起27起暴发的98株副溶血性弧菌分为11个血清型,5个Ribo型.优势血清型为03:K6,优势Ribo型为vp-EcorI-002型.全部分离菌株均携带toxR基因,97株携带tdh基因,1株携带trh基因.有多起暴发事件分离到多个血清型的副溶血性弧菌.结论 血清分型和PCR方法检测毒力基因,是副溶血性孤菌暴发事件实验室诊断的有用方法.对于从一起暴发事件中检出的不同血清型的副溶血性弧菌需要确认各菌株与暴发的关系.     

辽宁省市售水产品中副溶血性弧菌的污染状况及耐药性分析

分析辽宁市售水产品副溶血性弧菌污染状况、毒力基因分布及耐药情况。方法 共采集420份水产品,应用国标方法和基质辅助激光解吸/电离飞行时间质谱(MALDI-TOF MS)对水产品中分离的副溶血性弧菌进行鉴定,并对分离菌株进行毒力基因及耐药性检测。结果 经国标方法和MALDI-TOF MS鉴定分离得到123株副溶血性弧菌,总检出率为29.29%(123/420)。不同种类、不同类别水产品副溶血性弧菌检出率差异均有统计学意义,海水产品检出率为33.44%,其中海水贝类检出率最高为49.51%;另外淡水产品中河蟹检出率较高为61.29%。分离的123株菌tlh基因全部阳性,未检测到tdh和trh基因,对氨苄西林耐药性显著,耐药率为94.31%。结论 辽宁省市售水产品不同程度受到副溶血性弧菌污染,尤其在河蟹中存在较高检出,应引起重视,并采取有效措施预防由水产品引起的副溶血性弧菌食源性疾病。同时,MALDI-TOF MS作为一种快速、准确、高通量的全新微生物鉴定技术,实现了对副溶血性弧菌的特异性快速鉴定。     

食品中副溶血性弧菌toxR和tdh基因双色荧光PCR检测方法的建立

目的 建立对副溶血性弧菌（Vibrio parahaemolyticus）特异性检测toxR（跨膜转录激活蛋白）基因和tdh（热稳定性直接溶血素）毒力基因的Taqman探针双色荧光PCR检测方法。方法 根据副溶血性弧菌toxR基因和tdh基因,分别设计引物和探针,建立Taqman探针双色荧光PCR扩增体系,进行特异性、灵敏度试验;对副溶血性弧菌分离菌株实施检测,了解其tdh基因和tdh基因分布情况。结果 结果表明,副溶血性弧菌标准菌株和3株从食物中毒患者中分离获得的分离株均出现toxR基因和tdh扩增曲线,而溶藻弧菌、单增李斯特菌等31株弧菌属其他菌株和肠杆菌科的菌株未见扩增曲线。从食品中分离的37株副溶血性弧菌分离株均未携带tdh毒力基因。副溶血性弧菌检测灵敏度可达到3.6×102 cfu/mL。结论 该方法可用于同时检测食品中副溶血性弧菌的特异性和毒力基因。     

北京市市售带壳牡蛎致病性弧菌污染状况调查

目的了解北京市市售带壳牡蛎致病性弧菌污染状况。方法 2014年2~11月每月在某水产品批发市场的摊位抽样200只带壳牡蛎,共80份样品(其中腮和肠样品分别为40份)。用常规培养方法检测牡蛎腮和肠(含便)中致病性弧菌,对副溶血性弧菌进行血清学分型,荧光定量PCR检测副溶血性弧菌毒力基因tdh、trh和tlh。结果 80份牡蛎样品中,致病性弧菌阳性样品检出率为62.50%(50/80),副溶血性弧菌阳性菌株检出率为33.75%(27/80),溶藻弧菌阳性菌株检出率为31.25%(25/80);各牡蛎腮和肠样品中,致病性弧菌阳性检出率为67.50%(27/40)和57.50%(23/40);27株副溶血性弧菌共9种血清型;毒力基因检测结果表示,tlh均为阳性,tdh和trh均为阴性。结论北京市市售带壳牡蛎中致病性弧菌污染严重,以副溶血性弧菌和溶藻弧菌检出为主。     

北京一起副溶血性弧菌和非O1/O139霍乱弧菌共感染导致急性胃肠炎暴发事件病原检测分析

目的 对一起副溶血性弧菌和非O1/O139霍乱弧菌共感染导致急性胃肠炎暴发事件进行实验室病原学分析。方法 采用实时荧光PCR方法对4个病例肛拭子、12件可疑污染食品和8件环境涂抹的增菌液进行多种腹泻病原检测,将副溶血性弧菌和霍乱弧菌分离培养,并对分离株进行全基因组测序,获取菌株毒力基因和耐药基因,基于核心基因组单核苷酸多态性构建聚类树。结果 4件病例肛拭子增菌液荧光PCR检测副溶血性弧菌结果均为toxRVP+/tdh+/trh-,其中2件肛拭子荧光PCR检测霍乱弧菌结果为阳性。病例肛拭子副溶血性弧菌培养法检出率为100%(4/4),分离株均为toxRVP+/tdh+/trh-,血清型均为O4:KUT;病例肛拭子霍乱弧菌培养法检出率为50%(2/4),均为非O1/O139血清型,其中1分离株为toxR_VC+/ctx-/t3ss+。可疑污染食品副溶血性弧菌培养法检出率为66.67%(8/12),环境涂抹副溶血性弧菌检出率为12.50%(1/8),可疑污染食品和环境副溶血性弧菌分离株均为toxRVP+/tdh-/trh-;可疑污染食品霍乱弧菌检出率为25.00%(3/1...     

海口市市售贝类海产品副溶血性弧菌污染调查及耐药和毒力基因研究

目的了解海口市市售贝类海产品中副溶血性弧菌的污染情况、菌株血清学分型情况以及不同来源菌株的耐药情况,分析海口市市售贝类海产品受副溶血性弧菌污染的特点。方法 2014—2016年,按照GB 4789.7—2013《食品安全国家标准食品微生物学检验副溶血性弧菌检验》和《国家食品污染和有害因素风险监测工作手册》对五类海产品(白贝、排海、毛蚶、蛏子、芒果螺)进行副溶血性弧菌分离鉴定和血清学分型,采用实时荧光聚合酶链式反应(PCR)进行毒力基因检测,采用K-B法对分离菌株进行相关耐药分析。结果五类海产品样品共157份,其中65份样品检出副溶血性弧菌,白贝的检出率最高,为63.6%(21/33)。所分离的65株副溶血性弧菌主要血清群为O3和O5,完全分型26株,总体分型率为40.0%,其中以O1∶K25为主要血清型。65株菌对氨苄西林普遍耐药(95.4%,62/65),对头孢噻肟的中介率较高(33.8%,22/65),对8种抗生素产生了5种耐药谱。65株分离菌株神奈川试验结果均为阴性,且均未检出与致病性相关的耐热直接溶血素(TDH)及耐热相关溶血素(TRH)。结论海口市市售贝类副溶血性弧菌污染较重,应加强养殖区域海水水质的监测力度,预防副溶血性弧菌感染。     

北京市水产品污染与感染病例中副溶血性弧菌血清型和毒力基因型的比较研究

目的对北京市夏季市售水产品污染与感染病例中副溶血性弧菌血清型和毒力基因型进行比较研究,为评估食品安全风险监测的目的与意义提供思路,为北京市水产品副溶血性弧菌污染与临床感染病例的关联性研究提供技术支持。方法对采集的水产品样品和哨点医院腹泻患者粪便样本进行副溶血性弧菌的分离鉴定,采用血清玻片凝集法对分离出的副溶血性弧菌进行血清分型,PCR方法检测菌株的tlh、tdh、trh基因。结果 2014年7~9月共采集水产品样品164份,检出副溶血性弧菌80份,总污染率为48.78%;其中淡水产品污染率为38.78%(19/49),平均菌量浓度为66.63 MPN/g;海水产品污染率为53.04%(61/115),平均菌量浓度为38.14 MPN/g。80株副溶血性弧菌分属于9个血清群,其中O2群28株,占35.00%,O1群11株,占13.75%,O5群10株,占12.50%。80株菌tlh基因均为阳性,只有1株菌携带tdh毒力基因,所有菌株trh毒力基因均为阴性。哨点医院腹泻病人粪便样本中分离鉴定副溶血性弧菌21株,血清型O3∶K6占61.90%(13/21),O4:K8占28.57%(6/21);毒力基因型tdh(+)/trh(-)占95.24%(20/21),tdh(-)/trh(-)占4.76%(1/21)。结论来源于食品样品的副溶血性弧菌绝大部分不具备致病性,而导致消费者腹泻的副溶血性弧菌绝大部分携带致病性毒力基因,表明目前的食品安全风险监测结果不能作为评估副溶血弧菌导致的食源性疾病暴发和散发的依据。     

中国部分水产品副溶血性弧菌毒力基因的分布特征

目的了解中国部分水产品中副溶血性弧菌毒力基因的分布情况。方法通过聚合酶链反应测定从中国部分水产品中分离的192株副溶血性弧菌是否携带毒力基因tdh、trh,及种特异性基因tlh、toxR。结果192株实验菌株tdh全阴性,4株trh阳性,毒力基因携带率2.08%;而tlh、toxR的携带率均为100%。结论中国副溶血性弧菌水产品分离株毒力基因携带率非常低。     

基于环介导等温扩增法(LAMP)检测上海市售贝类产品中副溶血性弧菌的毒力菌株

基于环介导等温扩增法(LAMP)对上海市8-10月市售贝类产品中副溶血性弧菌毒力菌株(tdh和trh毒力基因)进行检测分析,共检测贝类样品180份,6个常规品种,实验同时采用PCR测定方法进行对比。结果表明,含tdh和trh毒力基因的副溶血性弧菌在市售贝类中的检出率分别是12.77%和11.66%,PCR的分析结果为11.11%和7.78%。对分离的毒力菌株进行血清型分型后发现了2株O3:K6型副溶血性弧菌,其中1株为毒力基因双阳性菌(tdh+/trh+)。2株O3:K6型副溶血性弧菌的PFGE条带型相似度较高(相似度90%)。这些结果表明上海市售贝类产品中副溶血性弧菌毒力菌株存在一定的污染,应引起足够重视。双阳性O3:K6型副溶血性弧菌的出现值得关注,应对各血清型菌株尤其是O3:K6型副溶血性弧菌的流行情况加强监测。PCR检测结果对比分析表明,LAMP方法适用于贝类产品中副溶血性弧菌毒力菌株的检测分析。     

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.