Foodbome pathogens identification

Electronic nose technology is relatively new and holds great promise as a detection tool in food safety area because it is portable, rapid and has potential applicability in foodbome pathogen identification or detection. On the basis of the work described above, we have demonstrated that the E-nose integrated with chemometrics can be used to identify pathogen bacteria at genus, species and strains levels. 

Wilderdyke, M.R., Smith, D.A. and Brashears, M.M. (2004) Isolation, identification, and selection of lactic acid bacteria from alfalfa sprouts for competitive inhibition of foodbome pathogens. Journal of Food Protection, 67, 947-951. 

Electronic Nose Integrated with Chemometrics for Rapid Identification of Foodbome Pathogen 205... 

Section "Biochemistry" deals with biomarker identification, kinetics of enz3me reactions, selection of substances with anticancer properties, and the use of an electronic nose for the identification of foodbome pathogens. 

Plants produce a variety of chemicals to survive attacks by microbial invasion (Grayer and Harbome 1994). These metabolites are either preformed in the plant (prohibitins) or induced after infection (phytoalexins). Since phytoalexins can also be induced by abiotic factors such as UV irradiation, they have been defined as antibiotics formed in plants via a metabolic sequence induced either biotically or in response to chemical or environmental factors. Many of these substances have been identified as flavonoids (Cowan 1999). Extraction of flavonoids and identification of their antimicrobial activity is useful not only for finding new drugs but also for obtaining natural products useful as food additives to improve the shelf life and safety of foods. In fact, an aliment can be deteriorated by spoilage bacteria, that cause and develop unpleasant odours, taste and texture, whereas foodbome pathogenic bacteria may cause diseases with flu-like symptoms such as nausea, vomiting, diarrhoea, and/or fever. Food additives with antimicrobial activity can be used to overcome such problems, but consumers tend to reject the present use of additives obtained by chemical synthesis flavonoids, as additives derived from natural products, can be a valid and preferred alternative (Cowan 1999). 

Several additional instrumental techniques have also been developed for bacterial characterization. Capillary electrophoresis of bacteria, which requires little sample preparation,42 is possible because most bacteria act as colloidal particles in suspension and can be separated by their electrical charge. Capillary electrophoresis provides information that may be useful for identification. Flow cytometry also can be used to identify and separate individual cells in a mixture.11,42 Infrared spectroscopy has been used to characterize bacteria caught on transparent filters.113 Fourier-transform infrared (FTIR) spectroscopy, with linear discriminant analysis and artificial neural networks, has been adapted for identifying foodbome bacteria25,113 and pathogenic bacteria in the blood.5... 

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