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Bacteriophage and its Applications in Food
By
Rasha Mohamed Mahmoud
Supervised by
Prof. Dr. Zakaria Yehia Daw Dr. Mona Hussein Badawi
OUTLINESIntroduction to BacteriophageClassificationPhage Life CycleWhere we can find phages?Desirable properties of phages used as biocontrol agents in foodsBacteriophages for biocontrol of pathogens in foodSome reviews on Bacteriophage in food safetyLarge Scale Production and Purification StrategyBacteriophages in DetectionAdvantages of PhageChallenges in Bacteriophage and Measures to control
Introduction Obligate intracellular parasites that multiply inside bacteria by
making use of some or all of the host biosynthetic machinery
Felix d'HerelleIndependently discovered
again 1917
Frederick TwortIn 1915 Discovered Bacteriophage
ClassificationTaxonomy by, International Committee on Taxonomy of Viruses (ICTV)3 orders, 73 families, 9 sub -families, 287 genera and 1938 virus species
Classification Examples
Myoviridae T-even, P1, P2, G
Siphoviridae λ, T1, T5, MM1, A2
Podoviridae P22, N4, T3, T7, C1
Inoviridae M13, fd
Microviridae ΦX174
Tectiviridae ΦNS11, PRD1
Corticoviridae PM2
Leviviridae MS2, R17, f2, Qβ
Cystoviridae Φ6
Phage Fates
Phage Attack
Where we can find phages? In humans and animal intestines In running water In the soil Effluent outlets Sewage from corpsesDr. "Grammy bar" from the University of San Diego,
California, says that Bacteriophag viruses live in the human intestine does not harm him (Research 2013). On the contrary, is stick to the mucous layer of the intestines and are covered, if approached her cell bacteria hung out and penetrate the cell wall and enter them and multiply. Then explodes bacteria cell and out of a large number of viruses Bacteriophage . Thus, service to the people of this virus leads, at the same time provide them with the appropriate center for human living
Desirable properties of phages used as biocontrol agents in foodsPhage should be strictly lyticPhage should have a broad host rangeDetermine the complete genome sequence of phagesLack of transduction of bacterial DNAOral feeding studies of phages should show no adverse effectsPhage preparation should be stable over storage and applicationPhage should be amenable to scale up for commercial production
Bacteriophages for biocontrol of pathogens in food From
Farm
To
Fork
Some reviews on Bacteriophage in food safetyPathogen Description References
Listeria monocytogenes 8 log reduction in Melon juice, 2.10 log reduction in Pear juice by ListexTM p100
Oliveira et al., 2014
E coli O157:H7 Fresh cut leafy greens: EcoshieldTM reduction upto 3.24 log unit compared with MAP results 4.24 Log reduction
Boyacioglu et al., 2013
Salmonella Reduction of 6 log units of S. typhimurium by bacteriophage Φ st1 in Chicken
Wong et al., 2014
Vibrio parahemolyticus 2.76 log reduction in oysters by phage VPp1 Rong Rong, 2014
Campylobacter Testing by applying in the drinking water of chicken and tested for the Campylobacter in feces and also slaughtered and checked, in feces 7.5 PFU and reduction of 3.5 log unit
Kittler et al., 2013
Large Scale Production and Purification Strategy
Cultivation of Bacteria
Inoculating the Bacteriophage
Separation of lysate by filtration
Primary Purification
Secondary Purification (Size Exclusion Chromatographic
focussing)
Bacteriophages in Detection
Bacteriophage will help to attach bacteria specifically, which will be detected by a sensor or by any means
Advantages of PhageUbiquitous in natureHighly active and specificGenetically amenableVersatile use along the food chainTools for detecting pathogensSource of potent antimicrobial agents
Challenges in Bacteriophage and Measures to controlBacterial resistance to bacteriophages
A mixture or cocktail of different phages (Abuladze et al ., 2008) Broad specificity to account for differences in bacterial strains High multiplicities of infection (MOI) ≥103−106 (Yoichi et al. (2004))
Large-scale safer production systems Use of non virulent bacteria in production
Enhance activity in food systems Modelling phage behaviour
Some products and companies involved in the phage business
Any Questions?
References http://www.biocontrol-ltd.com/ with thanks to Dr. David R. Harper • http://www.phagetherapycenter.com/ • http://en.wikipedia.org/wiki/Phage_therapy • http://recursive-nature.com/bacteriaphoge/ Haq I U et al (2012) Bacteriophages and their Implications on Future Biotechnology: A Review J
Virol 9: Wang Y, Ye Z, Ying Y. New trends in impedimetric biosensors for the detection of foodborne
pathogenic bacteria. Sensors (Basel) 2012; 12:3449-71;PMID:22737018; http://dx.doi.org/10.3390/ s120303449
Stewart GS, Jassim SA, Denyer SP, Newby P, Linley K, Dhir VK. The specific and sensitive detection of bacterial pathogens within 4 h using bacteriophage amplification. J Appl Microbiol 1998; 84:777-83; PMID:9674131; http://dx.doi.org/10.1046/j.1365-2672.1998.00408.x
Power point presentation (2015) www.slideshare.net/