Epigallocatechin gallate and Lactobacillus plantarum culture supernatants exert bactericidal activity and reduce biofilm formation in Clostridium perfringens

• Published in: Folia microbiologica 2021-10, Vol.66 (5), p.843-853
• Main Authors: Aguayo-Acosta, Alberto, Franco-Frías, Eduardo, Heredia, Norma, Merino-Mascorro, Jose A., Dávila-Aviña, Jorge E., Vidal, Jorge E., García, Santos
• Format: Article
• Language: English
• Subjects: Antibacterial activity; Applied Microbiology; Bactericidal activity; Biofilms; Biomedical and Life Sciences; Clostridium perfringens; Dogs; Environmental Engineering/Biotechnology; Epigallocatechin gallate; Food contamination; Food safety; Food sources; Gene expression; Genes; Immunology; Lactobacilli; Lactobacillus plantarum; Life Sciences; Microbiology; Original Article; Pathogenesis; Plants; Quorum sensing; Spores; Strains (organisms); Transcription
• ISSN: 0015-5632; 1874-9356
• DOI: 10.1007/s12223-021-00891-z

Clostridium perfringens forms biofilms and spores that are a source of food contamination. In this study, the antibacterial activities of Lactobacillus plantarum culture supernatants (LP-S), LP-S fractions, and the plant-derived compound epigallocatechin gallate (EG) were evaluated. Specifically, their effects on the viability and biofilm-forming ability of C. perfringens were assessed. Moreover, the expression of quorum sensing-regulated genes associated with the pathogenesis of this microorganism and that of genes involved in biofilm formation was also investigated. The results showed that both EG and the LP-S exerted bactericidal activity against all C. perfringens strains tested. The minimal bactericidal concentration (MBC) of EG was 75 µg/mL for all strains but ranged from 61 to 121 µg of total protein per mL for LP-S. EG exerted only minor effects on biofilm formation, whereas LP-S, particularly its 10 and 30 K fractions, significantly reduced the biofilm-forming ability of all the strains. The antibiofilm activity of LP-S was lost following preincubation with proteases, suggesting that it was mediated by a proteinaceous molecule. The treatment of C. perfringens with either EG or LP-S did not change the transcript levels of two CpAL ( C. perfringens quorum–sensing Agr-like system)-related genes, agrB and agrD , which are known to be involved in the regulation of biofilms, suggesting that LP-S exerted its biofilm inhibitory activity downstream of CpAL signaling. In summary, we demonstrated the bactericidal activity of EG and LP-S against C. perfringens and antibiofilm activity of LP-S at a subinhibitory dose. Our results suggested that these compounds can be further explored for food safety applications to control agents such as C. perfringens .