能力验证试验中沙门氏菌的分离与鉴定

目的研究能力验证试验中沙门氏菌的分离与鉴定。方法以中国合格评定认可委员会提供的冻干细菌混合物作为能力验证样品,根据能力比对试验中给定盲样可以水化的特性,采用GB 4789.4-2010中的方法对沙门氏菌进行传统鉴定和快速鉴定,并对检出的沙门氏菌进行生化鉴定和血清学鉴定。结果采用沙门氏菌快速鉴定方法,盲样的鉴定结果与GB 4789.4-2010中的结果一致,确定所检出的沙门氏菌为都柏林沙门氏菌。结论与传统鉴定方法相比,沙门氏菌快速鉴定方法在同等试验条件下具有快速准确、操作简单的特点,可以作为一种快速筛查方法运用在微生物能力验证领域。     

Salmonella contamination in pigs at slaughter and on the farm: a field study using an antibody ELISA test and a PCR technique

An antibody ELISA test and a PCR method for identifying the risk of Salmonella contamination were compared in a field study on the same lots of animals in a slaughterhouse. The results were compared to investigations carried out on two farms with different prevalences of Salmonella antibody-positive animals. Salmonella antibody ELISA testing was carried out on all 383 meat juice samples derived from the diaphragm pillar muscle of each pig. Salmonella DNA analysis was performed by PCR technique on small intestine samples with lymph nodes from all 383 pigs, and on tonsils from the last 129 pigs. The 383 animals tested came from 32 different pig farms. Furthermore, the herd antibody blood serum status against Salmonella spp. of weaners was determined on two selected pig fattening farms, one with low and one with high seroprevalence in meat juice. A total of 7.0% (ELISA cut-off OD% > or =40) of the slaughtered pigs from 6 of 32 fattening farms were seropositive. Salmonella DNA was found in 16.4% of the jejunum/lymph nodes (383 animals) and in 15.5% of the tonsils (129 animals). Salmonella DNA was found in the jejunum/lymph nodes of 41% of the seropositive pigs. However, serotitres were also positive in only 17.5% of all pigs positive in the jejunum DNA test. Two farms were selected for further investigation: farm 13 (F13), with a high prevalence of seropositive pigs, 29.0%, Category II; and F11, with 9.4%, Category I. However, categorization according to the blood serum tests of the fattening pigs after on-farm testing was very different: F13 had 5% positive animals (Category I); and F11, 23.3% (Category II). The study led to the following results and recommendations: First, ELISA tests are useful for the detection of farms that are regularly contaminated with Salmonella, but such tests cannot give information on the infectious status of a single animal (or a group) at the point of slaughter. Second, it is crucial that management measures are taken to prevent the spread of infections by trade and transport: piglets should be supplied exclusively by a single, well-known producer, and finishers should be tested serologically on farm before going to slaughter. Third, ELISA tests and the PCR method are suitable for the detection of Salmonella and are recommended as analytical tools for all pork quality control programmes. Fourth, animals from suspicious farms should always be slaughtered at the end of the slaughter day, followed by thorough cleaning and disinfection.     

Prevalence of pigs infected by Salmonella Typhimurium at slaughter after an enterocolitis outbreak

A cross-sectional study was performed to estimate the prevalence of slaughter pigs infected by Salmonella typhimurium after an enterocolitis outbreak in a commercial pig farm, which was characterised by diarrhoea during the growing phase. Anatomopathological and histopathological findings were suggestive of salmonellosis, which was further confirmed by isolation of S. typhimurium from organs and faeces samples from diseased animals. Ileocolic lymph nodes were aseptically collected from 43 pigs during slaughter procedures. The estimated prevalence of Salmonella-infected pigs was 53.48% [confidence interval (CI): 42.94:64.02%]. This finding demonstrates that the carriage of S. typhimurium at slaughter might be high if pigs originate from a batch previously affected by Salmonella-enterocolitis outbreak at the pre-harvest pork production chain.     

Salmonella in raw meat and by-products from pork and beef

After campylobacteriosis, salmonellosis is the second main cause of human bacterial enteritis in Germany. Salmonella is known to colonize the gastrointestinal tract of animals without producing any clinical signs. Therefore, carcasses can become contaminated with Salmonella at the time of slaughter. During an 11-month period, a total of 4,170 raw meat samples and by-products from beef and pork, obtained from seven different slaughterhouses in Southern Germany, were screened by the VIDAS system for Salmonella in this study. Positive results were confirmed by isolation of the pathogen on selective agars. The overall percentage of Salmonella-positive samples was 1.4% by the VIDAS system and 0.7% by culture confirmation. Salmonella was detected in 1.8% of pork samples by the VIDAS system and in 1.1% of samples by culture. In beef samples the presence of Salmonella was verified in 0.6% of samples by the VIDAS system and in 0.1% by culture on selective agars. The highest contamination rates were found in porcine and bovine tongue samples. Salmonella was detected in porcine samples throughout the year, except in samples collected in July, and a slight increase was observed in the colder months. The VIDAS system was shown to be an efficient screening method for the detection of Salmonella, with the advantage of a reduced analysis time.     

南京地区猪肉源中沙门氏菌分子分型及耐药性分析

沙门氏菌是造成我国食源性疾病的常见细菌之一,也是肉类消费过程中密切监测的重点对象。在2018年~2021年期间,共计采集了南京市545份猪肉源食品样本,利用选择性培养法分离得到44株沙门氏菌,采用血清学方法和分子生物学方法（MLST）对其进行分型鉴定,并分析其耐药性。结果表明,市售样本中共计检出44株沙门氏菌,平均检出率为8.07%,其中内脏样本检出率相对最高（检出率为30.49%）;血清型分析表明,检出的菌株中以鼠伤寒沙门氏菌（Salmonella typhimurium）、罗森氏沙门氏菌（Salmonella rissen）、德尔卑沙门氏菌（Salmonella derby）和伦敦沙门氏菌（Salmonella london）4种血清型沙门氏菌最为常见;基因分型表明,ST19型为猪肉源中优势沙门氏菌株,占比为20.45%;检出的沙门氏菌中,38株菌株对四环素具有明显耐药性,占全部检出菌株的86.36%,而对头孢他啶、头孢噻肟和头孢西丁的耐药不超过10%。此外,对检出的1株多重耐药性沙门氏菌耐药基因分析发现,共筛查出了包括7大类抗生素及与耐药相关的基因。该实验详细分析了南京市场猪肉源食品中沙门氏菌污染状况,也为后期沙门氏菌的综合防治提供了理论依据。     

运用实时荧光PCR法辅助鉴定能力验证样品中的沙门氏菌

目的运用实时荧光PCR法辅助鉴定能力验证样品中的沙门氏菌,以提高检验准确度。方法采用传统的增菌、选择性培养、生化鉴定方法进行样品检验,实时荧光PCR法作为辅助手段对BPW增菌液及可疑菌落进行扩增,最后用API20E鉴定系统对可疑菌落进行确认。结果 3个样品经增菌、选择性培养、生化鉴定后均无显著符合沙门氏菌菌落特征及生化特征的可疑菌落;缓冲蛋白胨水增菌液实时荧光PCR法扩增结果表明样品S02为可疑样品,其分离得到的菌落S02-4有典型扩增曲线;经API20E鉴定系统确认,样品S02为阳性样品,阳性菌为猪霍乱沙门氏菌亚利桑那亚种。结论实时荧光PCR法操作简单,准确度高,可作为传统检验方法的有效补充。     

能力验证中沙门氏菌的分离鉴定与血清分型

目的通过参加NIFDC-PT-098乳粉中沙门氏菌检验的能力验证,提高本实验室的检测能力,增强实验室竞争力。方法依据GB 4789.4-2016《食品安全国家标准食品微生物学检验沙门氏菌检验》中的方法,对2份样品中的沙门氏菌进行分离和血清学鉴定。并以全自动荧光免疫分析系统(MINI VIDAS)进行快速初筛,利用全自动微生物生化鉴定系统(VITEK2)对分离出的疑似菌进行生化鉴定。结果编号CODE423检出鼠伤寒沙门氏菌,其血清分型为O:4,5,12,H:I;1,2。编号CODE484未检出。结论本次能力验证获得满意结果,发现以国标法为基准,优先选用沙门氏菌属显色培养基平板和XLD平板为参照,同时使用VITEK2和MINI VIDAS作为辅助进行检测,综合这几种方法可确保实验结果的准确性,这为以后检验使用辅助方法检测提供了参考依据。同时本次能力验证也促进了实验室保持较高的检验水平。     

Competitive exclusion of Salmonella from the gut of neonatal and weaned pigs

Our laboratory has developed a bacterial competitive-exclusion (CE) culture against enteropathogens (which are considered human foodborne pathogens) for use in swine. In this article, we document the effects of this CE culture, PCF1, on cecal colonization by and fecal shedding of Salmonella Choleraesuis in neonatal and weaned pigs and its effects on the horizontal transmission of this pathogen between weaned penmates. Piglets treated with the PCF1 culture twice within their first day of life and challenged with Salmonella 48 h after birth shed Salmonella at a significantly (P < 0.05) lower rate than did control pigs in experiment 1. Significant reductions of the pathogen were also observed in the cecum, the cecal contents, the ileocolic junction, and the colon contents (P < 0.05). In experiment 2, culture of the cecal contents and lymph nodes revealed a significant reduction in Salmonella isolated from PCF1-treated pigs (P < 0.05). Pigs in experiment 3 were treated as pigs in experiments 1 and 2 were: however, they were followed through day 10 postweaning. Significant reductions in shedding were noted for treated groups both pre- and postweaning (P < 0.05). Experiments 4 and 5 assessed the effects of PCF1 treatment on the horizontal transmission of Salmonella between littermates that were followed through day 14 postweaning. In these experiments, litters were divided into untreated contacts (UC), untreated seeders (US), treated contacts (TC), and treated seeders (TS). Overall, TC in experiment 4 shed Salmonella at a significantly lower rate than UC and US did (P < 0.05). In experiment 5, the transmission of Salmonella was significantly reduced for litters in which TS or TC were present, as evidenced by reduced shedding of Salmonella by both treated and untreated animals within these litters (P < 0.05). TS shed less often than US did, resulting in reduced levels of Salmonella shedding by both treated and untreated contacts (P < 0.05). Litters containing both TC and UC or both TC and US also shed Salmonella at lower rates than did litters in which only UC and US were present (P < 0.05).     

Time course of infection with Salmonella typhimurium and its influence on fecal shedding, distribution in inner organs, and antibody response in fattening pigs

This is the first longitudinal study conducted over the entire 5-month fattening period in pigs to investigate the infection dynamics of Salmonella Typhimurium and the association between antibody response and the prevalence of these bacteria in feces. A total of 16 weaning pigs were infected with Salmonella Typhimurium DT104 followed by clinical examination and blood and fecal sampling until slaughter 138 days postinoculation. To investigate fecal shedding rates and distribution patterns of Salmonella in internal organs regarding premortem stress, one group of swine was transported before slaughter; the other group was slaughtered without being transported. A positive correlation between bacteremia-associated fever and fecal shedding rate was observed, although 69% (11 of 16) of infected pigs had no diarrhea. All animals excreted Salmonella Typhimurium at high levels within 2 weeks postinoculation; thereafter, the number of positive pigs declined and Salmonella shedding became intermittent. In contrast, the proportion of pigs that tested seropositive was higher over the entire fattening period (except during the first 3 weeks postinoculation), revealing the advantage of enzyme-linked immunosorbent assay for Salmonella screening on herd level. Concerning the distribution in internal organs and cross-contamination during slaughter, the highest level of Salmonella was detected in tonsils and jejunal and ileocecal lymph nodes, whereas salmonellae could not be detected in muscle, spleen, and liver. No specific influence of transport-induced stress on Salmonella shedding rates in feces and distribution patterns in organs was observed.     

Salmonella cross-contamination in swine abattoirs in Portugal: Carcasses, meat and meat handlers

In this study the occurrence of Salmonella in swine, pork meat and meat handlers along with their clonal relatedness is evaluated at abattoir level. Samples from the lymph nodes, carcass surface and meat of 100 pigs and 45 meat handlers were collected in eight abattoirs (July 2007-August 2008). Salmonella isolates were serotyped and genotyped by pulsed-field gel electrophoresis (PFGE). From the pigs tested, 42 produced at least one positive sample. A relatively high frequency of Salmonella occurrence was found in the ileoceacal lymph node samples (26.0%), followed by carcass (16.0%) and meat samples (14.0%). However, ileoceacal lymph nodes that test positive for Salmonella are not found to be a predictor of positive test results further on in the process. Besides the slaughterhouse environment, meat handlers were identified as a possible source of subsequent contamination, with 9.3% of the sample testing positive. Diverse Salmonella enterica serotypes were detected, mainly S. Typhimurium and the monophasic variant S. 4,[5],12:i:-, but also S. Derby, S. Rissen, S. Mbandaka, S. London, S. Give, S. Enteritidis and S. Sandiego, in total corresponding to 17 PFGE types. Our results demonstrate that besides a high level of Salmonella swine contamination at pre-harvest level, slaughtering, dressing, cutting and deboning operations are contributing to the occurrence of clinically relevant clones (e.g. S. Typhimurium DT104 and S. 4,[5],12:i:-) in pork products. This study also highlights the possibility of an ongoing Salmonella community being spread by abattoir workers.     

Rapid detection of Salmonella in pet food: design and evaluation of integrated methods based on real-time PCR detection

Reducing the risk of Salmonella contamination in pet food is critical for both companion animals and humans, and its importance is reflected by the substantial increase in the demand for pathogen testing. Accurate and rapid detection of foodborne pathogens improves food safety, protects the public health, and benefits food producers by assuring product quality while facilitating product release in a timely manner. Traditional culture-based methods for Salmonella screening are laborious and can take 5 to 7 days to obtain definitive results. In this study, we developed two methods for the detection of low levels of Salmonella in pet food using real-time PCR: (i) detection of Salmonella in 25 g of dried pet food in less than 14 h with an automated magnetic bead-based nucleic acid extraction method and (ii) detection of Salmonella in 375 g of composite dry pet food matrix in less than 24 h with a manual centrifugation-based nucleic acid preparation method. Both methods included a preclarification step using a novel protocol that removes food matrix-associated debris and PCR inhibitors and improves the sensitivity of detection. Validation studies revealed no significant differences between the two real-time PCR methods and the standard U.S. Food and Drug Administration Bacteriological Analytical Manual (chapter 5) culture confirmation method.     

Unveiling contamination sources and dissemination routes of Salmonella sp. in pigs at a Portuguese slaughterhouse through macrorestriction profiling by pulsed-field gel electrophoresis

Sixty-nine isolates of Salmonella sp. isolated from the ileum, tonsils, carcass and mandibular and ileocolic lymph nodes of individual pigs slaughtered for consumption in one abattoir were analyzed using serotyping and macrorestriction profiling by Pulsed-Field Gel Electrophoresis (RFLP-PFGE), in order to identify clonal relationships. XbaI macrorestriction was able to distinguish 18 genotypes among the eight identified serotypes: Salmonella Typhimurium (4 genotypes), Salmonella Rissen (3), Salmonella Tennessee (2), Salmonella Enteritidis (2), Salmonella 4,[5],12:i:- (4), Salmonella Give (1), Salmonella Anatum (1), and Salmonella Derby (1). Except for one sample, the serotype and the genotype identified in the samples from the same pork were always the same, allowing to unravel possible dissemination routes of Salmonella sp. through these pork tissues and equate presumptive sources of contamination or infection. Highly significant associations (p < 0.001) were observed for the presence of Salmonella sp. in the ileum and in the ileocolic lymph nodes, as well as between the carcass contamination and the presence of Salmonella sp. in others samples of the correspondent slaughtered pig, such as the ileum, the ileocolic and mandibular lymph nodes and the tonsils. Moreover, 80% of the pigs with ileum and ileocolic lymph nodes positive samples also presented the same salmonella genotype in the correspondent tonsils and, among pigs with positive tonsils, 70% also carried the same genotype in the corresponding mandibular lymph nodes. The occurrence of cross-contamination was also detected, since a genotype identified in other pigs slaughtered in the same day was found in 31% of positive carcasses. The global analysis of the genotypes suggested three different sources of pig infection: the farm of origin, the transportation and the lairage. A particular attention should be paid to the last one, since the majority of the isolates from pig samples were related to infection in the lairage. Since the presence of Salmonella sp. in the ileum of pigs and faeces ingestion promotes tonsils infection and internal dissemination of the agent through the mandibular lymph nodes, as well as drainage to the ileocolic lymph nodes, a potential risk exists at slaughter for Salmonella sp. contamination in the carcasses during pork processing. This risk may be increased by incorrect evisceration techniques and by hygienically inappropriate meat inspection procedures, especially those concerned to the mandibular lymph nodes incisions.     

食品中沙门氏菌检测方法研究进展

沙门氏菌病是一种在自然界广泛存在的人畜共患病，可以引起人类败血症、胃肠炎等疾病，还能导致动物伤寒、副伤寒，严重者会危及人、畜的生命。因此，建立沙门氏菌的快速检测方法对预防和控制沙门氏菌感染至关重要。目前沙门氏菌的检测技术有传统培养法、免疫学检测技术、分子生物学检测技术和近年来发展起来的如生物传感器检测技术、纳米技术、基于适配体检测技术等新型技术。该文总结了沙门氏菌各种检测方法的原理、优点和缺点及研究情况，并对沙门氏菌的检测方法及应用前景进行了展望。     

用Dot—ELISA方法检测生肉中的沙门菌

目的 检测生肉中的沙门菌带菌情况,为预防沙门菌食物中毒提供理论参数.方法 应用Dot-ELISA法对西宁市某屠宰厂85份猪胴体,101份羊胴体和71份牛胴体进行沙门菌的检测,同时用常规分离培养鉴定技术作为对照试验.结果 Dot-ELISA法检出沙门菌阳性率分别为76.47％( 65/85),55.44％ (56/101)和46.48％(33/71);而常规分离培养鉴定技术检出沙门菌阳性率分别为78.82％( 67/85)、47.52％ (48/101)和43.66％(31/71).两种方法的阳性符合率分别为86.57％、85.71％和81.82％,两种方法在检测中的差异无显著性(P＞0.05).结论 Dot-ELISA法检测沙门菌快速、准确,且与分离培养法阳性符合率较高;生肉中沙门菌带菌现象较为严重,存在一定的食品安全隐患.     

Evaluation of a 24-hour bioluminescent enzyme immunoassay for the rapid detection of Salmonella in chicken carcass rinses

A bioluminescent enzyme immunoassay (BEIA), using Salmonella-specific monoclonal antibody M183 for capture and biotinylated monoclonal antibody M183 for detection, was developed with InteLite AB streptavidin-biotinylated firefly luciferase complex as a reporter. Salmonella cultures were preenriched in buffered peptone water with shaking for 6 h at 37 degrees C and then selectively enriched in Muller-Kauffmann tetrathionate (MKTT) broth and modified semisolid Rappaport-Vassiliadis (MSRV) medium for 16 h at 42 degrees C. After enrichment, the total test time for the BEIA was 1.5 h. The analytical sensitivity of the BEIA ranged from 6.0 x 10(2) CFU/ml to 1.2 x 10(5) CFU/ml in MKTT and from 1.4 x 10(5) to 2.3 x 10(6) CFU/ml in MSRV using six Salmonella serovars prevalent in Canada. With enrichment cultures, the BEIA detected 1 CFU of Salmonella Typhimurium and Salmonella Enteritidis in 25 ml of chicken rinses. Representative strains of 10 Salmonella serovars were detected, and cross-reactivity was not observed with 25 non-Salmonella foodborne bacteria. The BEIA performance was assessed by testing 420 poultry samples, which were analyzed in parallel with the standard MSRV culture method. The BEIA detected 117 (27.88%) Salmonella-positive samples, whereas the standard MSRV culture method detected 124 (29.5%). The BEIA had a sensitivity of 64.5% and a specificity of 87.5% compared to the standard MSRV culture method. However, similar specificities and sensitivities were obtained when the standard MSRV culture method was compared to the BEIA (sensitivity = 68.4% and specificity = 85.5%). Neither method detected 100% of the Salmonella found in the samples tested, and statistical analyses indicated no significant difference between the two methods. In summary, the BEIA offers another alternative for the detection of Salmonella, with the additional advantage of providing a 24-h test for detecting Salmonella in chicken carcass rinses. The results obtained in this research indicate that tests are still needed for the isolation and detection of Salmonella that will establish the true prevalence of Salmonella in chicken samples.     

Comparison of a real-time PCR method with a culture method for the detection of Salmonella enterica serotype enteritidis in naturally contaminated environmental samples from integrated poultry houses

Conventional culture methods have traditionally been considered the "gold standard" for the isolation and identification of foodborne bacterial pathogens. However, culture methods are labor-intensive and time-consuming. A Salmonella enterica serotype Enteritidis-specific real-time PCR assay that recently received interim approval by the National Poultry Improvement Plan for the detection of Salmonella Enteritidis was evaluated against a culture method that had also received interim National Poultry Improvement Plan approval for the analysis of environmental samples from integrated poultry houses. The method was validated with 422 field samples collected by either the boot sock or drag swab method. The samples were cultured by selective enrichment in tetrathionate broth followed by transfer onto a modified semisolid Rappaport-Vassiliadis medium and then plating onto brilliant green with novobiocin and xylose lysine brilliant Tergitol 4 plates. One-milliliter aliquots of the selective enrichment broths from each sample were collected for DNA extraction by the commercial PrepSEQ nucleic acid extraction assay and analysis by the Salmonella Enteritidis-specific real-time PCR assay. The real-time PCR assay detected no significant differences between the boot sock and drag swab samples. In contrast, the culture method detected a significantly higher number of positive samples from boot socks. The diagnostic sensitivity of the real-time PCR assay for the field samples was significantly higher than that of the culture method. The kappa value obtained was 0.46, indicating moderate agreement between the real-time PCR assay and the culture method. In addition, the real-time PCR method had a turnaround time of 2 days compared with 4 to 8 days for the culture method. The higher sensitivity as well as the reduction in time and labor makes this real-time PCR assay an excellent alternative to conventional culture methods for diagnostic purposes, surveillance, and research studies to improve food safety.     

Comparison between VIDAS automatic enzyme-linked fluorescent immunoassay and culture method for Salmonella recovery from pork carcass sponge samples

VIDAS Salmonella (VIDAS-SLM) is an automated system that uses the enzyme-linked fluorescent assay method to detect Salmonella species. This study evaluated the efficacy of the VIDAS-SLM method in detecting Salmonella species in pork carcass sponge samples gathered from 10 slaughter plants in Taiwan. Two hundred fifty-seven pork carcass sponge samples were screened by the VIDAS-SLM method and by the culture method in parallel. While 18 sponge samples were found to test positive by both methods, the VIDAS-SLM method detected four additional positive samples for which the culture method failed to recover Salmonella. The specificity of the VIDAS-SLM method was found to be 0.98, and its sensitivity was 1.0, since no false-negative results occurred. Artificially inoculated Salmonella at concentrations as low as 5.0 x 10(0) CFU/ml was detected in the heat-inactivated sponge sample in the presence or absence of 5.0 x 10(4) CFU of Citrobacter freundii per ml. Thus, the VIDAS-SLM method is a rapid screening method and a potential alternative to the time- and labor-intensive culture method.     

Mucosal competitive exclusion to reduce Salmonella in swine

A mucosal competitive exclusion culture has been shown to reduce or eliminate Salmonella spp. in poultry. Using similar techniques, a mucosal competitive exclusion culture from swine (MCES) was produced from the cecum of a 6-week-old pig. Suckling pigs were inoculated with 5 ml of MCES by oral gavage within 6 h postfarrowing (PF) and again at 24 h PE All pigs were challenged with 10(3) CFU of Salmonella Choleraesuis at 48 h PF by intranasal instillation, including pigs from two sows that had not been given MCES. Clinical signs and rectal swabs were monitored daily, and pigs were allowed to suckle throughout the experiment. All pigs underwent necropsy on day 7 PF, and presence of Salmonella was determined in both qualitative (10 tissues) and quantitative (two tissues) samples. Clinical signs were inapparent in all pigs throughout the experiment. Recovery of Salmonella from rectal swabs was variable. However, 28% of the gut tissues were positive from the MCES-treated pigs versus 79% from the control pigs. A 2- to 5-log10 reduction of Salmonella in the cecal contents or ileocolic junction was observed in the MCES-treated pigs when compared with the controls. These data indicate that use of MCES may be a useful approach for control of Salmonella.     

沙门氏菌检验及鉴定方法研究进展

沙门氏菌在一个多世纪以来被认为是引起人类和动物疾病的主要食源性病原体,因此也导致了高昂的医疗和经济成本。努力开发有效和可靠的沙门氏菌检测方法至关重要。本文主要对目前用于沙门氏菌检测的技术和方法进行了综述,根据检测原理的不同分为常规培养方法、基于免疫学测定的方法、基于核酸测定的方法和生物传感器。传统常规培养法虽然在沙门的鉴定方面的准确性和特异性有不可否认的优势,但是也具有一定的缺陷,比如耗时长等。新兴的分子生物学快速检测及鉴定等方法能够快速、准确的对沙门氏菌进行鉴定,但可能对设备、技术人员、环境要求较高。随着生物学、化学、物理等学科的快速发展,应寻求多学科结合、取长补短,使准确、快速、灵敏检测食品中沙门氏菌成为现实。     

基于适配体的沙门氏菌检测方法研究进展

沙门氏菌(Salmonella)是重要的食源性致病菌,能引起人和动物中毒并引起多种严重的疾病,对人类健康造成了巨大危害,因此建立简单高效的检测方法是预防和控制沙门氏菌疾病的关键。适配体(aptamer)是通过指数富集配体的系统进化技术(systematic evolution of ligands by exponential enrichment, SELEX)从构建的随机文库中筛选得到一段对靶标物质具有高度亲和力和特异性的寡核苷酸序列,多种食品致病菌的适配体已被成功筛选并广泛应用于食品中致病菌的检测。本文对当前沙门氏菌检测技术进行简单论述,重点介绍了基于适配体的沙门氏菌检测方法,对各种方法的优势和缺点进行了比较和总结,并论述了适配体的发展及应用。