Lactobacilli isolation from dental plaque and saliva of a group of patients with caries and characterization of their surface properties

Abstract

The oral cavity is a complex ecosystem colonized by micro-organisms which play different roles. The aims of this study were to identify Lactobacillus strains from the teeth and saliva of children lacking in dental care and to study the surface characteristics related to the adhesion capability of these micro-organisms. The population considered is from Tucumán, Argentina. It is characterized by a dmfs index over 5 and an absence of dental care. Lactobacilli were isolated and identified by microscopic observations, biochemical tests and modified API CH 50. Bacterial surface studies included: hydrophobicity, acid and basic characteristics, blood cell agglutination and salt aggregation. Thirty strains were isolated. The major group was facultative heterofermentative. The surface characteristic studies did not indicate that lactobacilli are hydrophobic, neither do they show high basic nor acid charges. Lactobacilli isolated from saliva auto-agglutinated and also agglutinated ABO red blood cells. Salt aggregation was not a characteristic property. In this preliminary work, lactobacilli from teeth and saliva from this specific population were not demonstrated to have relevant adhesion properties.