Screening and characterization of medicinal plants extracts with bactericidal activity against Streptococcus mutans.

The aim of the present study was to perform a screening of extracts obtained from 15 medicinal plants using water (at 25 and 90 °C) or ethanol (at 25 °C), to bactericidal activity against cariogenic S. mutans ATCC 25175, as well as to carry out the preliminary phytochemical characterization of the extracts and HPLC/MS assay for selected extracts. The extractions were carried out for 5 h at 400 rpm. Only five from 45 tested extracts were selected based on their antibacterial activity. The IC₅₀ varied from of 28 ppm for Quercus ilex up to 250 ppm for Jatropha dioica. Different polyphenolic and quinic acids, flavonoids, anthocyanin or tyrosol were identified by HPLC/MS in selected extracts from Rosa gallica L., Jatropha dioica Sessé, Mimosa tenuiflora (Willd.) Poir, Quercus ilex L., and Solanum nigrum. The obtained results confirm that selected extracts are good candidates to be used for cariogenic bacteria control.