Effect of mucoadhesive agent HEC on herbal extracts retention and VSC producing bacteria reduction in an experimental oral biofilm

Abstract

Mucoadhesive tablets containing herbal formulation have been previously shown to reduce oral malodour. The aim of the present in vitro study was to test the effect of the mucoadhesive agent hydroxyethylcellulose (HEC) added to a liquid phase herbal extract formulation on the mucoadhesive retention of the active ingredients and their effect against malodour production. Experimental oral biofilms were grown on mucin coated glass slides treated with liquid phase solutions of herbal extract with or without HEC as well as saline and 0.2% chlorhexidine as controls. Biofilms were quantified for volatile sulfide compounds (VSC) producing bacteria using CLSM and sampled for a salivary incubation assay to test for malodour production (odour judge), VSC production (Halimeter) and salivary protein degradation (SDS-PAGE). Results showed that the addition of HEC to the herbal extracts solution has significantly increased its mucin retained activity against malodour producing bacteria and their resulting malodour and VSC production and proteolytic activities. Taken together, results of the present study suggest that the addition of HEC to a liquid phase herbal extract solution may increase its bioavailability time and efficacy. However, due to the limitations of this in vitro study additional clinical investigations are needed.