Adelaide Almeida, Carla Pereira, Rui Rocha, Jesus Romalde, Ricardo Calado and Leonor Nunes
Posters-Accepted Abstracts: Biol Syst Open Access
Salmonella enterica serovar typhimurium (Salmonella typhimurium) is the most common causative agent of human gastroenteritis after consumption of contaminated seafood. The use of lytic bacteriophages against this pathogen can be a new and promising approach for the prevention of food-contamination and food-borne infection. This study investigated the potential application of the bacteriophage SE-5 during depuration to reduce S. typhimurium in cockles (Cerastoderma edule) at different multiplicity of infection (MOI). Cockles were infected with 106 colony-forming units (CFU)/mL of S. typhimurium in the seawater and each infected group was treated with four different MOI values: 100, 10, 1 and 0.1. Infected cockles were depurated in non-recirculating seawater at 16�°C for 12 hour. After S. typhimurium accumulation at 16�° C, the initial mean values of bacteria in cockles were 6.20 log CFU/g. Depuration with phages at MOI 0.1 was the best condition to inactivate S. typhimurium in cockles, the concentration was reduced by 1.7 log CFU/g after 2 hours of depuration. Reduction for the other MOI values (MOI=1; MOI=10; MOI=100) was 1.13, 1.21 and 2.10 log CFU/g after 6 hours, 12 hours and 12 hours of treatment respectively. To our knowledge, this is the first report of a depuration trial using bacteriophage in the cockle treatment process. The data of this study indicate clearly that the application of the bacteriophages could reduce significantly the population of S. typhimurium in infected cockles. Moreover, cockles could be maintained alive during the depuration process. Therefore, the application of bacteriophage was effectively proven to be useful for shellfish depuration.
Adelaide Almeida is an Assistant Professor at the Department of Biology from the University of Aveiro (Portugal), where she got her PhD degree in 2001. She is an Integrated Member of the Associated Laboratory Centre for Environmental and Marine Sciences (CESAM). In the previous years, she was involved in the development and application of alternative methods to the use of antibiotics such as photo dynamic therapy and phage therapy and has publications in these fields.
