Autor(es): Oliveira, Márcia ; Carvalho, Marta ; Teixeira, Paula
Data: 2023
Identificador Persistente: http://hdl.handle.net/10400.14/43190
Origem: Veritati - Repositório Institucional da Universidade Católica Portuguesa
Assunto(s): Bacillus cereus; Cytotoxicity; Emetic toxins; Enterotoxins; Foodborne spore-formers; Toxigenic profile
Bacillus cereus is estimated to be responsible for 1.4–12% of all food poisoning outbreaks worldwide. The objective of this study was to investigate the toxigenic potential of 181 isolates of B. cereus previously recovered from different types of berries and berry products (strawberries, raspberries, blackberries, and blueberries) by assessing the presence of enterotoxin genes (hblA, hblC, hblD, nheA, nheB, nheC, and cytK) and an emetic toxin cereulide synthetase gene (ces). The cytotoxic activity on Caco-2 cells was also evaluated for the two isolates containing the gene cytK. Twenty-three toxigenic profiles were found. The nheABC (91.7%) and hblACD (89.0%) complexes were the most prevalent among the isolates, while the cytK and ces genes were detected in low percentages, 1.1% and 3.3%, respectively. In addition, the nheABC/hblACD complex and ces genes were detected in isolates recovered throughout the production process of blackberries and strawberries. The cytotoxic activity on Caco-2 cells was also observed to be greater than 60% for isolates containing the cytK gene.
