abstract
The present study investigated the potential application of the bacteriophage (or phage) phT4A, ECA2 and the phage cocktail phT4A/ECA2 to decrease the concentration of Escherichia coli during the depuration of natural and artificially contaminated cockles. Depuration in static seawater at multiplicity of infection (MOI) of 1 with single phage suspensions of phT4A and ECA2 was the best condition, as it decreased by similar to 2.0 log CFU/g the concentration of E. coli in artificially contaminated cockles after a 4 h of treatment. When naturally contaminated cockles were treated in static seawater with single phage suspensions and the phage cocktail, similar decreases in the concentration of E. coli (similar to 0.7 log CFU/g) were achieved. However, when employing the phage cocktail, a longer treatment time was required to obtain comparable results to those achieved when using single phage suspensions. When naturally contaminated cockles were depurated with phage phT4A in a recirculated seawater system (mimicking industrial depuration conditions), a 0.6 log CFU/g reduction of E. coli was achieved after a 2 h of treatment. When the depuration process was performed without phage addition, a 4 h treatment was necessary to obtain a similar decrease. By combining phage therapy and depuration procedures, a reduction in bivalves depuration period can be achieved for, thus decreasing the cost associated with this procedure and even enhance the quality and safety of depurated bivalves destined for human consumption. (C) 2016 Elsevier Ltd. All rights reserved.
keywords
OYSTERS CRASSOSTREA-GIGAS; HIGH-HYDROSTATIC-PRESSURE; VIBRIO-PARAHAEMOLYTICUS; IN-VITRO; SALMONICIDA INFECTION; BIOLOGICAL-CONTROL; PURE CULTURE; HALF SHELL; X-RAY; BACTERIOPHAGE
subject category
Biotechnology & Applied Microbiology; Food Science & Technology; Microbiology
authors
Pereira, C; Moreirinha, C; Teles, L; Rocha, RJM; Calado, R; Romalde, JL; Nunes, ML; Almeida, A
our authors
Catarina Moreirinha
Post-Doc Fellowshipacknowledgements
This work was supported by FEDER through COMPETE - Programa Operacional Factores de Competitividade, and by National funding through Fundacao para a Ciencia e a Tecnologia, within the research projects FCOMP-01-0124-FEDER-013934 and PROMAR 31-03-05-FEP-0028. Thanks are also to Centre for Environmental and Marine Studies (project Pest-C/MAR/LA0017/2013), and to Department of Biology of University of Aveiro, and Organic Chemistry Research Unit (QOPNA) (project PEst-C/QUI/UI0062/2013; FCOMP-01-0124-FEDER-037296). Financial supports to Pereira C. in form of a PhD grant (SFRH/BD/76414/2011), Moreirinha C. in form of a Postdoctoral grant (ENV/ES/001048) and Rocha R. J. M. in form of Postdoctoral grant (SFRH/BPD/99819/2014). We thank Joana Pais for graphical designer of depuration system.