Dissertations / Theses on the topic 'Bacillus cereus group species'
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Barker, Margaret. "Population structure of the Bacillus cereus group." Thesis, Heriot-Watt University, 2006. http://hdl.handle.net/10399/2145.
Full textOh, Mi Hwa School of Chemical Engineering & Industrial Chemistry UNSW. "Ecology of toxigenic bacillus species in rice products." Awarded by:University of New South Wales. School of Chemical Engineering and Industrial Chemistry, 2006. http://handle.unsw.edu.au/1959.4/23942.
Full textPires, Fazion Fernanda. "Role of plasmids of Bacillus cereus group in insect larvae." Thesis, Paris, Institut agronomique, vétérinaire et forestier de France, 2017. http://www.theses.fr/2017IAVF0005/document.
Full textBacillus cereus (Bc) and Bacillus thuringiensis (Bt) are two closely related species. Bc is a pathogenic species responsible for gastroenteritis by food-borne. Bt is an entomopathogenic bacterium, which the lifecycle in insect larvae is controlled by quorum sensing systems, such as Rap/Phr, which regulates processes such as sporulation, biofilm formation and conjugation. The presence of these genes in plasmids has been described, furthermore, plasmids have been involved in bacterial adaptation to their ecological niche. In order to understand the role of the plasmids to these species, two complementary works were carried out. First, insect larvae, a privileged ecological niche of Bt strains, were infected with Bc and Bt strains harboring different plasmid contents. Their fitness were evaluated by vegetative cells and spore counts at four time points. Bt and Bc strains were classified into five groups according to the bacterial fitness. In these groups, the plasmid affects positively or negatively the bacterial fitness. The results demonstrated that for B. cereus group strains, getting a pathogenicity plasmid is not enough to effectively increase bacterial population, colonizing insect hosts. The second study characterized the rap/phr system encoded by the cryptic plasmid pHT8_1. The Rap8 protein inhibited the sporulation process in insect larvae. This protein was directly inhibited by the active signaling peptide Phr8. The Rap8/Phr8 system may allow the bacteria to exert a tight control of the sporulation process in the host cadaver for optimizing the multiplication, the survival and the dissemination of the bacteria. Thus, the results of the second study showed that the plasmids can provide advantages for the adaptation and the evolution of B. thuringiensis in its ecological niche, while the results of the first study indicate that B. cereus group strains must have a suitable genetic background to display a high fitness allowing optimal multiplication and dissemination of the bacterial population within insect larvae
Atkinson, Deborah Jane. "Stress response and inorganic poly-phosphate in the Bacillus group bacteria." Thesis, University of Bath, 2010. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.538113.
Full textTaylor, J. M. Walsh. "Identification and isolation of emetic toxin producing Bacillus Cereus and heat-stable toxins from other Bacillus species." Thesis, Glasgow Caledonian University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415442.
Full textDocherty, Pauline Fletcher. "The survival during milk processing of bacillus cereus with the potential to cause food-borne illness." Thesis, Glasgow Caledonian University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325996.
Full textFrentzel, Hendrik [Verfasser]. "Detection, characterization and survival of Bacillus cereus group members in spices and herbs / Hendrik Frentzel." Berlin : Freie Universität Berlin, 2017. http://d-nb.info/1135184887/34.
Full textGdoura, épouse Ben Amor Maroua. "Maitrise des risques de contamination des produits alimentaires tunisiens par le groupe Bacillus cereus." Thesis, Rennes, Agrocampus Ouest, 2019. http://www.theses.fr/2019NSARB324.
Full textThis thesis focused on evaluating the level of risk represented by Bacillus cereus group bacteria in Tunisian food and testing the effectiveness of their control by treating industrial surfaces with bacteriophages. A collection of 191 isolates was created from 687 food matrices. Nearly 40% of the isolates were found to belong to the group, with high genetic diversity (143 PFGE profiles and 99 ERIC-PCR profiles) and an intermediate thermal profile (signatures 16S rDNA-1 m and-2 p). Nearly 60% of the group's isolates belong to the phylogenetic group III, which is potentially pathogenic. Spores have a higher rate of adhesion than vegetative cells. Twelve toxigenic groups have been identified.At least one of the genes of each of the NHE and HBL complexes are present, whether or not associated with bceT, cytK 2 and these. After 18 hours of incubation at 30°C, nearly 71% of the isolates are cytotoxic. Different combinations of virulence factors are associated with cytotoxic potential and a clear link appears between cytotoxicity and food type. The collection has been shown to be sensitive to many antibiotics, while it is resistant to ampicillin and novobiocin. Of the 7 bacteriophages selected, 5 have a unique protein profile while all have similar genome size and restriction profiles. They are used to prevent the formation of biofilms and to treat them. This work confirms the health risk associated with the presence of the B. cereus group in Tunisian foods and the promising role of bacteriophages as biocontrol tools
Fernandes, Meg da Silva 1984. "Enterococcus spp. e Bacillus cereus isolados do processamento de ricota: patogenicidade, formação de biofilmes multiespécie e detecção de autoindutores AI-2 = Enterococcus spp. and Bacillus cereus isolated from ricotta processing: pathogenicity, multi-species biofilm formation and detection of the autoinducer AI-2." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255699.
Full textTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-26T05:00:36Z (GMT). No. of bitstreams: 1 Fernandes_MegdaSilva_D.pdf: 2553051 bytes, checksum: ee968bf858cc0b427d8f6b79c37338b7 (MD5) Previous issue date: 2014
Resumo: Enterococcus faecium e Enterococcus faecalis são espécies de patógenos oportunistas que infectam principalmente imunocomprometidos. Estas espécies são encontradas em produtos lácteos e possuem capacidade de formar biofilme em superfícies que contatam com os alimentos. A sua remoção é muito dependente dos procedimentos de higienização. Os Enterococcus spp. utilizam o sistema de comunicação célula-célula (quorum sensing) para a formação de biofilmes. A formação de biofilme mono e multiespécie, a eficácia dos procedimentos de higienização no controle destes biofilmes e a produção de moléculas sinalizadoras de quorum sensing por cepas de E. faecalis, E. faecium, Bacillus cereus e Listeria monocytogenes foram avaliadas. Os ensaios foram realizados com cupons de aço inoxidável e variando-se a temperatura (7, 25 e 39 °C) e o tempo (0, 1, 2, 4, 6 e 8 dias). Após 1 e 8 dias de contato nas temperaturas de 25 e 39 °C, os cupons foram submetidos a diferentes processos de higienização. Os sanitizantes testados foram: hipoclorito de sódio (0,2%), ácido peracético (0,2%), quaternário de amônio (3,0%) e biguanida (1,0%). A detecção das moléculas sinalizadoras de quorum sensing AI-2 foi realizada através da avaliação do gene luxS e de ensaio biológico de bioluminescência. Nenhum dos micro-organismos avaliados foi capaz de formar biofilmes a 7 ?C. Enterococcus sp. foram capazes de formar biofilmes, com contagens acima de 8 log ufc/cm2 para as temperaturas de 25 e 39 °C após 8 dias de contato. Em cultivo multiespécie, a temperatura 25 °C favoreceu o desenvolvimento do biofilme de L. monocytogenes (contagens acima de 6 log ufc/cm2). Por sua vez, a 39 °C observou-se o efeito negativo no desenvolvimento do biofilme de L. monocytogenes em cultivo misto, com redução significativa nas contagens ao longo do tempo (valores abaixo de 0,4 log ufc/cm2). As contagens de B. cereus, para ambas as temperaturas em diferentes tempos de exposição situaram-se abaixo de 4,1 log ufc/cm2. Em contrapartida, a contagem de esporos de B. cereus evoluiu ao longo do tempo, atingindo contagens em torno de 4,6 log ufc/cm2. A limpeza com tensoativo aniônico complementada por outra etapa (limpeza ácida, limpeza ácida + sanitização ou sanitização) foi capaz de remover os biofilmes mono e multiespécie em todas as condições testadas. O ácido peracético foi o sanitizante mais eficiente e a biguanida o menos eficiente. Todas as cepas de Enterococcus spp. e B. cereus apresentaram o gene luxS e induziram o fenômeno de bioluminescência em Vibrio harveyi BB170, indicando a presença de autoindutores AI-2
Abstract: Enterococcus faecium and Enteroccus faecalis are opportunistic pathogens species that infect mainly immunocompromised individuals. These species are found in dairy products and are capable of forming biofilms on surfaces that contact with food. Their removal is highly dependent on the cleaning procedures. It is known that enterococci use the cell-cell communication (quorum sensing) to biofilm formation. The formation of mono- and multi-species biofilm, the effectiveness of sanitization procedures to control these biofilms and the production of signaling molecules of quorum sensing (AI-2) by strains of E. faecalis, E. faecium, Bacillus cereus and Listeria monocytogenes were evaluated in this work. The biofilms were grown on stainless steel coupons at various incubation temperatures (7, 25 and 39 °C) and times (0, 1, 2, 4, 6 and 8 days). After 1 and 8 days of contact at 25 and 39 °C, the coupons were subjected to different sanitation procedures: anionic tensioactive cleaning, acid-anionic tensioactive cleaning, sanitization, anionic tensioactive cleaning + sanitization, acidic- anionic tensioactive cleaning + sanitization and chlorinated alkaline cleaning. The sanitizers tested were: sodium hypochlorite (0.2%), peracetic acid (0.2%), quaternary ammonium (3%), and biguanide (1%). The detection of AI-2 molecules was performed by evaluating the luxS gene and biological bioluminescence assay. None of the microorganisms evaluated was able to form biofilms at 7 °C. Enterococcus sp. were able to form biofilms, with counts above 8 log CFU/cm2 for the temperatures of 25 and 39 °C after 8 days of contact. In multi-species culture, the temperature of 25 °C favored the development of L. monocytogenes biofilms (counts above 6 log CFU/cm2). On the other hand, at 39 °C it was observed a negative effect in the development of L. monocytogenes biofilms in mixed culture, with a significant reduction in counts over time (values below 0.4 log CFU/cm2). The counts of B. cereus, for both temperatures at different exposure times were below 4.1 log CFU/cm2. In contrast, the spore counts of B. cereus evolved over time, reaching scores of around 4.6 log CFU/cm2. The anionic tensioactive cleaning complemented by an aditional step (acid cleaning, acid cleaning + sanitization or sanitization) was able to remove mono- and multi-species biofilms in all tested conditions. The peracetic acid was the most effective sanitizer and the less efficient was biguanide. All strains of Enterococcus spp. and B. cereus showed the luxS gene and induced the phenomenon of bioluminescence in Vibrio harveyi BB170, indicating the presence of AI-2 autoinducers
Doutorado
Tecnologia de Alimentos
Doutora em Tecnologia de Alimentos
Dubois, Thomas. "Etude du système de communication cellulaire NprR-NprX au sein du groupe Bacillus cereus." Phd thesis, AgroParisTech, 2012. http://pastel.archives-ouvertes.fr/pastel-00770265.
Full textTecher, Marie Clarisse. "Altération des entremets à base d'ovoproduits : bactéries imliquées et mécanismes en jeu." Thesis, Rennes, Agrocampus Ouest, 2015. http://www.theses.fr/2015NSARB265.
Full textAmong the chilled egg products-based desserts, the French dessert “île flottante” is recognized as particularly sensitive from a microbiological point of view, because marketing is suffering from untimely spoilage occurrence that manufacturers wish to control. The work done in this thesis aimed to better understand these phenomena in order to better control them. We have shown that the dessert spoilage mainly concerned the custard cream and it was characterized by high bacterial count, frequent pH decreasing and sensory changes of appearance and smell. The main bacteria detected were identified as belonging to the Bacillus cereus group and Staphylococcus and Enterococcus genera. The possible involvement of bacteria from the pasteurized egg white, used for the egg white foaming, in the dessert spoilage issue was established.However, the involvement of bacteria from biofilms installed in the production environment or provided by other ingredients was also strongly suspected. The spoilage potential assessment of pure culture of a representative bacterial collection in sterile custard cream has shown that different types of sensory and physicochemical changes were expressed according to bacterial genus and that these changes were particularly correlated with the ability of bacteria to consume sugars and proteins of custard and to produce various volatile compounds with specific odorous. With these results, various tests have been proposed for a better control of the white egg batches orientation according to their microbiological quality and so to guarantee their safety with
Drewnowska, Justyna Małgorzata. "Genetic structure of environmental Bacillus cereus sensu lato strains isolated from Northeastern Poland." Phd thesis, 2016. http://hdl.handle.net/11320/4827.
Full textPrzedstawiciele B. cereus s.l. występują powszechnie w środowisku naturalnym i wywierają ogromny wpływ na zdrowie człowieka, przemysł spożywczy oraz rolnictwo. Te tlenowe laseczki z jednej strony produkują toksyny szkodliwe dla ludzi i zwierząt, ale znane są również z syntezy wtórnych metabolitów degradujących niebezpieczne związki chemiczne lub wspomagających wzrost roślin. Powyższe właściwości były intensywnie badane w odniesieniu do szczepów o szczególnym znaczeniu gospodarczym i medycznym. Tymczasem pokrewieństwo filogenetyczne i podłoże ekologicznej dywersyfikacji szczepów izolowanych z gleby nie jest dostatecznie poznane. Analizowałam strukturę genetyczną 297 szczepów B. cereus s.l. wyizolowanych z gleby (i) Narwiańskiego PN, (ii) Białowieskiego PN, (iii) Biebrzańskiego PN oraz (iv) gospodarstwa rolnego w Jasienówce. Zidentyfikowałam homogeniczną grupę bakterii (i) zdolną do wzrostu w niskiej temperaturze (ekotyp psychrotolerancyjny) oraz (ii) syntetyzującą ciemno-brązowy barwnik (ekotyp melaninowy). Analizy MLST wskazują na istnienie specyficznych genotypów wśród naturalnych populacji B. cereus s.l. Ponadto wykazałam istnienie trzech grup filogenetycznych, obejmujących zmienną liczbę B. cereus, B. thuringiensis i B. mycoides. Jednakże analizy typów sekwencyjnych i kompleksów klonalnych wskazują, iż środowiskowe izolaty B. cereus s.l. nie reprezentują jednego gatunku. Szczegółowe badania genetyczne, fenotypowe oraz biochemiczne środowiskowych szczepów B. cereus s.l., rzuciły nowe światło na ewolucję oraz ekologiczną adaptację tych bakterii.
B. cereus s.l. are widespread in natural environments and have a significant impact on human health, food industry, and agriculture. On one hand, members of this group synthetize various toxins harmful to humans, herbivores and invertebrates. On the other hand, they are also known as producers of various secondary metabolites whereby they degrade pollutants and promote the growth of plants and animals. These aspects have been intensively studied especially with regard to the B. cereus group members with the highest impact on human health and economy. Meanwhile, the phylogenetic relationships and the basis of ecological diversification of soil B. cereus s.l. remains largely undescribed. I investigated the genetic structure of 297 B. cereus s. l. soil isolates from diverse habitats in Northeastern Poland, such as (i) the Narew NP, (ii) the Białowieża NP, (iii) Biebrza NP, and (iv) agricultural land in Jasienowka. I identified homogenous groups of bacteria able to (i) growth in low temperature (psychrotolerant ecotype) and (ii) synthesis a dark pigment (melanotype). The MLST analysis indicates the existence of specific genotypes within the natural B. cereus s.l. populations. Phylogenetic studies revealed three major clades, in which B. cereus, B. thuringiensis and B. mycoides were intermixed. However, analysis of sequence types and clonal complexes indicate that environmental B. cereus s.l. do not represent one species. Detailed genetic, phenotypic and biochemical analyses of the environmental B. cereus s.l. strains shed new light on the evolution and ecological adaptation of these bacteria to specific soil habitats differing in scope of human activity.
Wydział Biologiczno-Chemiczny. Instytut Biologii.
Yang, I.-Chen, and 楊怡真. "Study on molecular detection methods and expression of nonhemolytic enterotoxin of Bacillus cereus group." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/53888625646966623397.
Full text臺灣大學
微生物與生化學研究所
96
Bacillus cereus foodborne diseases are a major concern worldwide. In Taiwan for the period 1991 to 2006, outbreaks due to B. cereus were exceeded only by Vibrio parahaemolyticus and Staphylococcus aureus. Five different enterotoxins and one emetic toxin of B. cereus have been characterized. To amplify all of the enterotoxin and emetic-specific sequences of the species in the B. cereus group, a multiplex polymerase chain reaction (multiplex PCR) with 12 primer pairs was established. The assay was successfully applied to analyze the toxigenic potential of 162 isolated B. cereus group strains. Results showed that there were 10 toxigenic patterns for all the test strains. All of the B. cereus strains carried at least one toxin gene. More than 70% of B. mycoides strains carried no known toxin genes. The toxin profiles and toxin genes of B. mycoides strains were significantly different from B. cereus strains although the two species were closely related. The results suggested that many B. mycoides strains might be less prone to cause food poisoning. It also indicated the importance of detecting the toxin genes together with the detection of the species in the B. cereus group. Conventional bacteriological methods for the detection and identification of species of the B. cereus group require individual biochemical confirmation and are laborious and time-consuming. PCR is a choice of rapid detection but can not quantify the contamination level. In practice, it is necessary to quantify the contamination level of B. cereus group cells. We selected nhe coding for Nhe as the target and developed a real-time PCR assay to quantify enterotoxigenic strains of the B. cereus group. The real-time PCR assay was evaluated using 60 B. cereus group strains and 28 others. The assay was also used to construct calibration curves for different food matrices and feces. The assay has an excellent quantification capacity, as proved by its linearity (R2>0.993), wide dynamic quantification range (102-107 CFU/g for cooked rice and chicken, 103-107 CFU/mL for milk, and 104-107 CFU/g for feces), and adequate relative accuracy (85.5-101.1%). For the low level contaminations, a most probable number (MPN) real-time PCR assay was developed that could detect as low as 100 CFU/mL. Both assays were tested with real food samples and shown to be considerably appropriate for B. cereus group detection and quantification. The cytotoxicity titers of Nhe components varied considerably and the level of Nhe seems to explain most of the cytotoxic activity of B. cereus isolates. In order to examine the regulatory mechanism of different Nhe-producing strains, the expression level of their nhe mRNA was determined by real-time reverse transcription PCR. Five candidates of internal controls were evaluated by three softwares. Meanwhile, the growth curves of different Nhe-producing strains were also compared. All studied candidate of internal control genes reached high expression stability. The growth curves showed no significant difference but the nhe mRNA expression level of high Nhe-producing strains was significantly higher than low Nhe-producing strains. The results indicated that the different Nhe expression levels between B. cereus strains may not be due to their growth difference but may be controlled at the transcribed level of nhe gene expression.
Branquinho, Fabiana Raquel Gouveia Pinto Nevado. "Unveiling population diversity, biosurfactant and antibacterial agents production of Bacillus pumilus group species." Doctoral thesis, 2014. https://repositorio-aberto.up.pt/handle/10216/74107.
Full textBranquinho, Fabiana Raquel Gouveia Pinto Nevado. "Unveiling population diversity, biosurfactant and antibacterial agents production of Bacillus pumilus group species." Tese, 2013. https://repositorio-aberto.up.pt/handle/10216/74107.
Full textFricker, Martina [Verfasser]. "Development of genotypic and phenotypic methods for the identification and differentiation of hazardous Bacillus cereus group strains / Martina Fricker." 2007. http://d-nb.info/987922661/34.
Full textChen, Yan-Lian, and 陳炎鍊. "Toxigenicity, partial 16S rRNA Sequence Comparison and the Use of a Multiplex PCR System for Bacillus cereus Group Cells." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/42593639360374484716.
Full text國立中興大學
食品科學系
86
B. cereus is one of the food pathogens which may cause foodbornedisease. It is also one of the important items for food inspection. Thus, tounderstand the relationship between its enterotoxins and cytotoxicity andto develop the multiplex PCR system for its detection is important. Based on the hblA gene for B component of hemolysin BL, bceTand entFM genes for enterotoxins, PCR primers aimed for the detectionof B. cereus enterotoxins have been developed. When the PCR resultsfor these enterotoxins specific primers were compared with the results ofcytotoxicity study using CHO cells, it was found that strains are positivewith any of these PCR primer pairs would show the positive cytotoxicityresult. The results for CHO cells cytotoxicity study were the same asthose obtained from immunoassay studies using BDE-VIA kit. As forthe multiplex PCR system, it was found that for hemolysin BL or bceTgene detection, when only one target strain was present in skim milk andcooked rice, the detection sensitivity reached to N*100 CFU per ml andper gram if a preculture step was performed prior to PCR. When twotarget strains were mixed to the food sample, however, it was found thatthe ratio of original cell numbers should be within 102 so that the targetstrains with lower cell numbers could be detectable. On the work forspecific PCR detection of B. cereus (not the B. cereus group cells), afterseries designing of PCR primers from 16S rRNA genes, we found PCRprimers which could allow the specific detection of B. cereus butexempted the interference from B. anthracis, B. mycoides and a standardstrain of B. thuringiensis. Four B. thuringiensis strains which interferethe PCR detection of B. cereus strains, however, were confirmed as B.thuringiensis strains since they generate cry gene specific product andthey were shown to produce parasporal crystals as examined by themicroscope. Sequence assay for the 16S rRNA genes showed that thesefour B. thuringiensis strains have the same DNA sequcnce as B. cereusstrains. Furthermore, on the position of base No. 165, two bases, ie. Cand T were observed. Whether two or more 16S rRNA operons would befound for B. thuringiensis strains need to be further investigated.
Sheu, Sen-Je, and 許勝傑. "Development and use of PCR primers for the detection of Bacillus cereus group cells and their hemolysin BL and/or enterotoxin." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/41189723063616646865.
Full text國立中興大學
食品科學系
85
Abstract Bacillus cereus is one of the important food pathogenes which may cause food poisoning. To investigate the relationship between B. cereus group cells and their toxigenicities and to develop rapid methods for the detection of B. cereus group cells and their hemolysin BL and/or B. cereus BceT enterotoxin is important. Based on the gene sequences coding for phospholipase C and sphingomyelinase, 16S rRNA, hblA of hemolysin BL B component and bceT, we have developed some novel PCR primers for the specific detection of B. cereus group cells and their genes coding for hemolysin BL and/or BceT toxins. The molecular weights generated from these PCR primers are 558 and 433 bp for B. cereus cells and 691 as well as 297 bp for hemolysin BL and BceT toxin, respectively. All the B. cereus group cells, such as B. cereus, B. thuringiensis, B. mycoides and B. anthracis would generate the expected PCR products with molecular weights equal to 558 or 433 bp, depending on the primers used. Of the 54 B. cereus strains tested, 18 were found to be hemolysin BL producing strains and 22 were bceT gene containing strains. In addition, for the 18 B. cereus strains containing hblA gene of hemolysin BL B component, further confirmation of their toxigenicity using blood agar hemolysis method and BCET-RPLA kit were performed. Results indicate that the PCR method might be used for the reliable detection of hemolysin BL productivity. Also, none of the bacterial strains other than B. cereus group cells would generate the false positive reaction. Thus, specificities of these PCR primers were assured. For food samples, such as whole milk, cooked pork, egg and cooked rice, which were inoculated with B. cereus cells, if a 8 hr preculture step was performed for target cells prior to the PCR, as low as N×100 cells per gram of the food sample could be detected. Also, the hemolysin BL and BceT toxin genes were detectable too.
Xu, Sheng-Jie, and 許勝傑. "Development and use of PCR primers for the detection of Bacillus cereus group cells and their hemolysin BL and/or enterotoxin." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/88155725683222242729.
Full textHung, Cho-Lien, and 洪秋蓮. "Development and application of Oligonucleotide array for the specific detection of Salmonella spp., Escherichia coli, Staphylococcus spp., Bacillus cereus group and Vibrio spp." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/05316621702577842099.
Full text國立中興大學
食品科學系
90
Abstract Vibrio parahaemolyticus, Staphylococcus aureus, Bacillus cereus group, Salmonella spp., pathogenic Escherichia coli are common pathogens which may cause food poisoning cases. Conventional methods for the detection of these bacteria spp. need the use of selection and differentiation medium followed by biochemical and serological identification steps. Such process is time consuming and laborious. Thus, development of rapid methods for the detection of these bacteria species is important. Biochip may be one of the choices for such purpose. Owing to the fact that 16S rRNA gene sequences have been used for bacteria identification and classification, in this study we thus tried to develop a 16S rRNA gene based biochip for the simultaneous detection of several different species of food pathogens. We found that 10 oligonucleotides arrayed on a biochip could be used for the differentiation of 5 genus of pathogenic bacteria. These bacteria genus are Salmonella spp., E coli, Bacillus cereus group strains, Staphylococcus spp. and Vibrio spp. etc. Five distinct chip hybridization patterns could be obtained for these 5 genus of bacteria spp. In additions, the hybridization pattern allowed us to find three specific oligonucleotide probes which in combination with a universal primer, could be used for the PCR primers specific for the detection of Salmonella spp. and E. coli. For pure culture, after 8 hrs preculture step, the detection sensitivity for theses bacteria was 100 CFU/ assay. For target cells in food samples, however, detection was not sensitive enough even after 8 hrs preculture step. In conclusion, the oligonucleotide array could be used for the identification of pure cultured bacteria but in use of it for food inspection, the process need some improvements.