食品中金黄色葡萄球菌检测方法研究进展

金黄色葡萄球菌是引起食物中毒的重要致病菌之一,检测食品中金黄色葡萄球菌对于预防和控制金黄色葡萄球菌引起的食物中毒具有重要意义。论述和分析了传统培养方法、传统检测方法的改进、免疫学方法、以分子生物学为基础的快速检测方法以及商业化快速检测方法。     

金黄色葡萄球菌肠毒素在食源性微生物中的研究进展

由细菌污染引起的食源性疾病依然是影响人类公共健康和食品安全的最大问题之一。其中,金黄色葡萄球菌是人类的一种重要病原菌,引起许多严重感染。金黄色葡萄球菌属于革兰氏阳性球菌,广泛分布于自然界,是引起化脓性疾病的重要病原菌,也是引起食品污染和细菌性食物中毒的一种重要细菌。食品受金黄色葡萄球菌污染后,不仅会腐败变质,而且部分菌株产生金黄色葡萄球菌肠毒素（Staphylococcal enterotoxins,SEs）而引起食物中毒,由金黄色葡萄球菌肠毒素引起的食物中毒占整个细菌性食物中毒的首位。所以,对SEs的研究以及快速、精确的检测和筛查,成为关键环节。本文拟对金黄色葡萄球菌肠毒素生物学性状、致病．洼、检验方法等方面的研究进展进行综述。当然,对金黄色葡萄球菌及其主要致病因子肠毒素的研究有待进一步深入与发展。     

致病性金黄色葡萄球菌的快速检测法

由乳与乳制品引起的葡萄球菌食物中毒现象,国内外均曾有报道。葡萄球菌食物中毒是由于致病性金黄色葡萄球菌在食品中繁殖产生的耐热性肠毒素所致。因此,致病性金黄色葡萄球菌在食品中的存在是个潜在的危险。我国食品卫生标准规定:乳与乳制品中不得检出致病性葡萄球菌。1986年,卫生部食品卫生监督检验所又提出了用于制备还原奶的进口奶粉,0.1克中不得有致病性葡萄球菌存在。根据国家食品卫生标准检验     

上海市食源性金黄色葡萄球菌分布状况

采集上海市食品样品(生牛乳、生鲜肉、水产品、速冻食品、果蔬、豆制品)505份,按国标GB 4789.10—2010《金黄色葡萄球菌检验》方法进行金黄色葡萄球菌的分离和鉴定,并利用PCR技术进行进一步验证。结果表明:505份食品样品中有117份检出了金黄色葡萄球菌,总检出率为23.2%,其中生鲜肉检出率最高,为32.9%;其次为生牛乳和速冻食品,分别为26.3%和26.7%;其他食品中金黄色葡萄球菌的检出率相对较低。该实验结果基本上反映了上海市各类食品中金黄色葡萄球菌的分布状况,为监控金黄色葡萄球菌引起的食物中毒及追溯污染源提供参考。     

生乳中金黄色葡萄球菌的风险评估

正金黄色葡萄球菌(Staphylococcus aureus,简称金葡菌)是引起细菌性食物中毒的重要病原菌之一,其广泛存在于自然环境中,对各种理化因素都有较高的抵抗力。无论在发达国家还是发展中国家,由金黄色葡萄球菌引起的食物中毒在细菌性食物中毒中均占较大比例~([1,2])。牛奶是重要的食品加工原料,是人类理想的营养食品。     

金黄色葡萄球菌及其快速检测方法

金黄色葡萄球菌(Saphylococcus aureus)是引起食品污染和细菌性食物中毒的一种重要细菌,在自然界中分布广泛.对金黄色葡萄球菌的生物学特性、流行病学特点及其致病性进行了简要综述,并重点介绍了金黄色葡萄球菌的几种快速检测方法.     

2017年广州市餐饮食品中金黄色葡萄球菌的调查分析

目的 了解餐饮食品中金黄色葡萄球菌的污染状况及分布, 确定高危食品的种类, 为预防金黄色葡萄球菌引起的食物中毒提供依据。方法 按照GB 4789.10-2016《食品安全国家标准 食品微生物学检验 金黄色葡萄球菌检验》对广州市5类500批次餐饮食品进行检验, 并经VITEK 2鉴定。结果 500批次餐饮食品中检出金黄色葡萄球菌9株, 检出率为1.80%, 其中熟肉制品和凉拌菜、寿司食品检出率分别为3.33%和3.00%。结论 广州市餐饮食品整体情况良好, 但存在着一定的风险安全隐患, 需加强对易受金黄色葡萄球菌污染的熟肉制品和凉拌菜、寿司等重点品种的监管。     

2010~2016年云南省食品金黄色葡萄球菌污染监测分析

目的 了解云南省食品中金黄色葡萄球菌的污染状况及分布, 并确定高危食品的种类, 为预防金黄色葡萄球菌引起的食物中毒提供依据。方法 2010~2016年从云南省16个地州市农贸市场、超市及酒店餐馆采样并监测14大类食品, 共计23723份。检测方法按GB 4789.10-2010《食品安全国家标准 食品微生物学检验 金黄色葡萄球菌检验》进行。结果 23723份样品中共检出金黄色葡萄球菌675株, 总检出率为2.85%; 7年的检出率从0.92%～11.13%, 2010年检出率最高, 2016年最低, 总体呈下降趋势; 全省16个地州市, 检出率在0.99%～6.91%, 其中昆明市、普洱市、丽江市检出率较高; 14类食品中有11类检出, 检出率在0.23%～6.68%, 其中肉与肉制品、速冻米面制品、餐饮食品污染金黄色葡萄球菌严重; 4种不同的采样环节检出率在0%～5.83%, 其中生产加工环节检出率最高; 不同季节检出率无明显差异; 预包装和散装样品的检出率分别为0.96%和3.94%, 散装食品检出率明显高于预包装食品。结论 云南省食品中金黄色葡萄球菌的污染严重, 需从食品的原料、加工、运输、储藏以及销售等全过程进行控制, 从而有效预防金黄色葡萄球菌引起的食物中毒。     

食源性金黄色葡萄球菌肠毒素及其检测方法

金黄色葡萄球菌是一种重要的食源性致病菌,在自然界中广泛分布,其引起的食物中毒是世界性的公共卫生问题。金黄色葡萄球菌肠毒素是引起金黄色葡萄球菌食物中毒的主要致病因子。目前共发现22种金黄色葡萄球菌肠毒素或类肠毒素(SEA-SEE、SEG-SET、SElU、SElU_2和SElV),其中具有催吐活性的被定义为肠毒素,没有催吐活性或者尚待验证的被定义为类肠毒素(SEl)。传统肠毒素SEA~SEE被报道是引起金黄色葡萄球菌食物中毒的主要肠毒素类型,但是大多数新型肠毒素或类肠毒素与食物中毒的关系还没有被真正认识。本文对近几年关于金黄色葡萄球菌肠毒素与食物中毒的关系、肠毒素的表达调控以及肠毒素检测方法的研究进展进行了总结,以期更好地了解金黄色葡萄球菌新型肠毒素致病性,为今后金黄色葡萄球菌食物中毒的预防和控制提供依据。     

2015年南宁市动物源性食品中金黄色葡萄球菌污染状况及耐药调查

目的调查2015年南宁市市售的动物源性食品中金黄色葡萄球菌的污染情况以及流行菌株的耐药情况,为食源性疾病监控提供数据支撑。方法随机采集市售的不同种类的动物源性食品383份,按照国标法进行金黄色葡萄球菌分离鉴定,并对分离到的28株金黄色葡萄球菌进行K-B纸片法耐药试验和PCR方法检测耐药基因。结果从383份动物源性食品中分离到28株金黄色葡萄球菌,耐药试验结果发现,其中10株为耐甲氧西林金黄色葡萄球菌,28株分离株对不同的抗菌药物有不同程度的耐药,并检测到了4类耐药基因。结论市售动物源性食品中有金黄色葡萄球菌污染,存在引发食物中毒的风险;分离株的耐药试验结果可以为南宁市金黄色葡萄球菌引起的食物中毒提供用药参考。     

An outbreak of food poisoning due to egg yolk reaction-negative Staphylococcus aureus

An outbreak of staphylococcal food poisoning due to an egg yolk (EY) reaction-negative strain occurred in Japan. Twenty-one of 53 dam construction workers who ate boxed lunches prepared at their company cafeteria became ill, and eight required hospital treatment. The outbreak showed a typical incubation time (1.5-4 h with a median time of 2.7 h) and symptoms (vomiting and diarrhea) of staphylococcal food poisoning. Staphylococcus aureus, which produces staphylococcal enterotoxin (SE) A, was isolated from four fecal specimens of eight patients tested. Scrambled egg in the boxed lunches contained 20-40 ng/g of SEA, and 3.0 x 10(9)/g of viable S. aureus cells that produced this toxin. All isolates from patients and the food were EY reaction-negative, coagulase type II, and showed the same restriction fragment length polymorphism (RFLP) pattern. We concluded that the outbreak was caused by scrambled egg contaminated with EY reaction-negative S. aureus. In Japan, outbreaks of staphylococcal food poisoning are mainly caused by EY reaction-positive S. aureus, and EY reaction-negative colonies grown on agar plates containing EY are usually not analyzed further for detection of S. aureus. The present outbreak suggested that EY reaction-negative isolates should be subjected to further analysis to detect the causative agents of staphylococcal food poisoning.     

生菜生产到消费全程金黄色葡萄球菌的定量风险评估

目的：评估即食生菜金黄色葡萄球菌（Staphylococcus aureus）引起食物中毒的风险,为风险管理措施的选择提供理论支持。方法：排查生菜在大棚和露地两种种植方式下各环境样本的污染率及污染水平,结合居民消费习惯和生菜中金黄色葡萄球菌的生长模型,描述生菜从农田到餐桌过程中金黄色葡萄球菌的变化,从危害识别、危害特征描述、暴露评估和风险特征描述4 方面评估我国即食生菜导致金黄色葡萄球菌中毒的风险。结果：大棚生菜的土壤中有金黄色葡萄球菌检出,检出率为0.04%,污染水平为－8.72～3.01（lg（CFU/g））,经过灌溉、采收、运输、销售、购买、贮藏及清洗等过程,生菜中金黄色葡萄球菌在食用前的污染平均值为－1.95（lg（CFU/g））,90%置信区间为－8.98～4.40（lg（CFU/g））。评估结果表明,我国因即食生菜导致金黄色葡萄球菌中毒的概率为2.72×10－4,每年因此引发的食物中毒病例约为77万 人。敏感性分析结果显示,土壤中金黄色葡萄球菌的初始污染水平对生菜中金黄色葡萄球菌的污染水平影响最大,其次为家庭贮藏温度及食用前清洗过程;控制生菜种植卫生环境、合理使用冰箱及清洗生菜可有效降低即食生菜引起金黄色葡萄球菌中毒的风险。     

Use of novel PCR primers specific to the genes of staphylococcal enterotoxin G, H, I for the survey of Staphylococcus aureus strains isolated from food-poisoning cases and food samples in Taiwan

Data regarding the incidence of the newly found enterotoxigenic Staphylococcus aureus strains in food poisoning cases and in food samples were to date not available in Taiwan. In this study, PCR primers specific for the detection of SEG, H and I genes, i.e., seg, seh and sei, were used for the assay of 55 human isolates of S. aureus negative to the classical enterotoxins (SEA-->SEE) detection. These isolates were from the fecal specimens of the patients suffering from food poisoning outbreaks. Only eight strains were found to have the seg, seh and sei. The presence of other bacterial pathogens, such as Vibrio parahaemolyticus, Bacillus cereus and Salmonella spp. and perhaps, strains producing other new staphylococcal enterotoxins, in the fecal specimens of these patients, may account for these food poisoning cases. For 139 strains from food samples, such as frozen Chinese foods, Chinese sausages and lunch meals, sea strains accounted for the major portion and it seemed to be the most common SE type to coexist with seg, seh and sei. Only two strains had sec and none of them had seg, seh or sei. For strains without the classical SE genes, only 13 strains had seg, seh and/or sei. The above results imply that seg, seh and sei S. aureus strains play only a minor role in food-borne outbreaks in Taiwan.     

发酵牛肉中金黄色葡萄球菌食物中毒缺失机制研究进展

本文介绍发酵牛肉金黄色葡萄球菌食物中毒缺失机制这一现象,国内外关于这种机制已经进行过部分研究,但是并没有作明确的解释,仍有待深入探讨。研究这一机制对于预防金黄色葡萄球菌食物中毒具有重大现实意义。     

Interactions between Staphylococcus aureus and lactic acid bacteria: an old story with new perspectives

Staphylococcus aureus is a gram positive opportunistic pathogen and a major concern for both animal and human health worldwide. In some contexts where Lactic Acid Bacteria (LAB) are the normal dominant microbiota, such as in fermented food or in the vaginal ecosystem, S. aureus sometimes colonises, persists, expresses virulence factors and produces food poisoning or urogenital infections, respectively. Studies on the interactions between LAB and S. aureus began a few decades ago and were pursued to shed light on the inhibitory capabilities that LAB might have on S. aureus growth and/or enterotoxin production in fermented foodstuffs. These early studies had the aim of developing methods to prevent staphylococcal food poisoning, thus improving food safety. More recently, the concept of vaginal probiotic LAB has emerged as a promising way to prevent urogenital infections, S. aureus being one of the potential pathogens targeted. This review provides an up-to-date look at the current hypotheses of the mechanisms involved in the inhibition of S. aureus by LAB in both the vaginal ecosystem and in fermented food ecosystems. We also emphasise that post-genomic approaches can now be envisioned in order to study these diverse and complex interactions at the molecular level. Further works in this field will open up new avenues for methods of biocontrol by LAB and/or for biotechnological uses of LAB-compounds to fight against the long-standing, yet incumbent menace of staphylococcal infection.     

Managing the risk of staphylococcal food poisoning from cream-filled baked goods to meet a food safety objective

The International Commission on Microbiological Specifications for Foods (ICMSF) has recently proposed a scheme for the management of microbial hazards for foods that involves the concept of food safety objectives (FSOs). FSOs are intended to specify the maximum levels of hazardous agents required to meet a given public health goal. This scheme offers flexibility for the food industry in terms of allowing the use of alternative but equivalent means for achieving a given FSO. This paper illustrates the application of the ICMSF model via the analysis of the microbiological hazard of Staphylococcus aureus in cream-filled baked goods. Cream-filled baked goods have a notorious history as vehicles for foodborne illness, particularly staphylococcal food poisoning. Although the numbers of cases reported in the United States and Europe have declined in recent years, staphylococcal food poisoning may be much more common than is recognized, particularly in other countries. The ICMSF principles for setting FSOs and the use of performance criteria, process criteria, and validation in relation to hazard analysis critical control point and good hygiene practice plans for managing S. aureus in cream-filled baked goods are described.     

金黄色葡萄球菌食品分离株肠毒素基因分布及分型研究

目的 对2006-2009年上海市Staphylococcus aureus(S.aureus)食品分离株进行肠毒素基因检测和基因分型研究,以了解肠毒素基因的分布规律及S.aureus的流行特点.方法 利用PCR方法检测食品中金黄色葡萄球菌肠毒素基因,包括5种传统肠毒素基因(SEA-SEE)和4种新型肠毒素基因(SEG-SEJ);利用脉冲场凝胶电泳法对49株食品分离株进行基因分型.结果 本研究发现49株食品分离株中有19株含有肠毒素基因,16株含有传统肠毒素SEA和SEC,且SEC占93.8％,并检测到新型肠毒素SEG、SEI、SEJ和SEH.PFGE法基因分型显示5株菌不能被分型,其余44株可分为28个基因型,表现为基因型的多样性,且分离自不同时间的菌株具有相同的带型.结论 应加强食品中S.aureus的监测分析,为其引起的食物中毒的预防和控制提供科学依据.     

食源性金黄色葡萄球菌肠毒素基因及其表达检测

金黄色葡萄球菌作为一种常见人类病原菌,可通过各种途径污染食品,引发食物中毒。其中,金黄色葡萄球菌肠毒素(SE)的分泌会大大增加其侵袭性和致病力。通过对比肠毒素基因的携带及其表达情况,有助于进一步分析肠毒素表达的环境条件,为产肠毒素金黄色葡萄球菌的防范和控制提供理论和数据支持。本研究采用PCR和3M^TMTecra^TM微孔板法分别检测33株食源性金黄色葡萄球菌中5种传统肠毒素SEA^SEE基因的携带及表达情况,结果显示,该批金黄色葡萄球菌中SE基因的检出率为100%,携带率最高和最低的分别为seb(48.48%,16/33)和see(9.09%,3/33)。而其中SE蛋白得到表达的菌株仅为63.64%(21/33),这表明不是有SE基因携带就一定可以有相应毒素蛋白的表达,可能还需相应的系统调控和适宜的环境因素。