Inhibitory effects of fruit berry extracts on Streptococcus mutans biofilms

• Published in: European journal of oral sciences Vol. 127; no. 2; pp. 122 - 129
• Main Authors: Philip, Nebu, Bandara, H. M. H. N., Leishman, Shaneen J., Walsh, Laurence J.
• Format: Journal Article
• Language: English
• Published: England Wiley Subscription Services, Inc 01-04-2019
• Subjects: Acid production; Architecture; Bacteria; biofilm ecology; Biofilms; Biofilms - drug effects; Biofilms - growth & development; Blueberries; Cranberries; Dental Caries; Dentistry; Disruption; Exopolysaccharides; Fruit - chemistry; Fruits; Humans; Metabolism; Microbial Sensitivity Tests; natural products; Pathogenicity; Pathogens; Phenols; Plant Extracts - chemistry; Plant Extracts - pharmacology; Polyphenols; Strawberries; Streptococcus infections; Streptococcus mutans; Streptococcus mutans - drug effects; Streptococcus mutans - growth & development; Streptococcus mutans - metabolism; Viability; Virulence; dental caries; natural products; biofilm ecology
• ISSN: 0909-8836; 1600-0722
• DOI: 10.1111/eos.12602

Dark‐colored fruit berries are a rich source of polyphenols that could provide innovative bioactive molecules as natural weapons against dental caries. High‐quality extracts of cranberry, blueberry, and strawberry, and a combination of the three berry extracts (Orophenol), were used to treat 24‐h‐old Streptococcus mutans biofilms. The grown biofilms were treated with the berry extracts at concentrations ranging from 62.5 to 500 μg ml−1. Treated biofilms were assessed for metabolic activity, acidogenicity, biovolumes, structural organization, and bacterial viability. The biofilms treated with the cranberry and Orophenol extracts exhibited the most significant reductions in metabolic activity, acid production, and bacterial/exopolysaccharide (EPS) biovolumes, while their structural architecture appeared less compact than the control‐treated biofilms. The blueberry extract produced significant reductions in metabolic activity and acidogenicity only at the highest concentration tested, without significantly affecting bacterial/EPS biovolumes or biofilm architecture. Strawberry extracts had no significant effects on S. mutans biofilms. None of the berry extracts were bactericidal for S. mutans. The results indicate that cranberry extract was the most effective extract in disrupting S. mutans virulence properties without significantly affecting bacterial viability. This suggests a potential ecological role for cranberry phenols as non‐bactericidal agents capable of modulating pathogenicity of cariogenic biofilms.