Journal of Microbial & Biochemical Technology

Occurrence of Clostridium difficile in edible bivalve molluscs in Spain

Joint Event on 4^th World Congress and Expo on Applied Microbiology & 2^nd International Conference on Food Microbiology

November 29-December 01, 2017 Madrid, Spain

Carmen Candel Perez, E Zapata Galian, G Ros Berruezo and C Martinez Gracia

University of Murcia, Espinardo, Spain

Posters & Accepted Abstracts: J Microb Biochem Technol

Abstract:

Statement of the Problem: Bivalve molluscs are a frequent source of viral and bacterial pathogens due to, among other factors, their filtering nature. Toxigenic C. difficile has been isolated from seafood samples with potential implications of transfer to humans. Purpose: The purpose of this study is to assess the occurrence of C. difficile as well as bacterial indicators (Salmonella spp, Escherichia coli and reducers) in edible bivalve molluscs in Spain. Methodology & Theoretical Orientation: A total of 129 samples, consisting in 123 samples of mussels (Mytilus galloprovincialis) and 6 oysters (Crassostrea cornucopiae), were purchased from outlets in the city of Murcia (southeast Spain). The isolation of C. difficile strains was carried out using enrichment broth suplemented with sodium taurocholate followed by etanol shock, prior to the culture on a selective media. The identification was carried out detecting Tpi gene using molecular techniques. The isolation and enumeration of bacterial indicators were investigated according to the ISO norm. Findings: C. difficile was isolated from 8.94% (11/123) of the mussels investigated, what supposes 20.8% (5/24) from Mediterranean Sea and 6.45% (6/93) from Northwest Atlantic. No C. difficile was detected in modified atmosphere packs or in cooked mussels. All oysters samples were negative for C. difficile. About the associated flora, Clostridium sulphite reducers appeared in 31% (40/129) of the analysed samples and E. coli appeared in 1.5% (2/129). Salmonella spp. was not present in any sample. These bacterial indicators were in accordance with the current legal requirements. Conclusion & Significance: These findings indicate that edible bivalve molluscs could be a potential source of C. difficile, with a slightly higher isolation rates than other studies. The intake of raw or poorly cooked contaminated bivalve molluscs with its spores could represent a risk for human health. Recent Publications 1. Montazeri N, Liu D, & Janes E (2015). Occurrence of toxigenic Clostridium difficile in Louisiana oysters (Crassostrea virginica) and environmental waters. Food and Nutrition Sciences. 6(11):1065-1070. 2. Norman K N, Harvey R B, Andrews K et. al. (2014) Survey of Clostridium difficile in retail seafood in College Station, Texas. Food Additives & Contaminants. 31(6):1127-1129. 3. Pasquale V, Romano V J, Rupnik M et. al. (2011) Isolation and characterization of Clostridium difficile from shellfish and marine environments. Folia Microbiology (Praha) 56:431-437 4. Pasquale V, Romano V, Rupnik M et. al. (2012) Occurrence of toxigenic Clostridium difficile in edible bivalve molluscs. Food Microbiology 31(2):309-312. 5. Troiano T, Harmanus C, Sanders I M J G et. al. (2015) Toxigenic Clostridium difficile PCR ribotypes in edible marine bivalve molluscs in Italy. International Journal of Food Microbiology. 208:30-34.

Biography :

Carmen Candel Perez is a candidate for a PhD in Food Science And Nutrition at Murcia University, Murcia, Spain. Her research interest involves the occurrence of C. difficile in food products.