Inhibitory effects of a water-soluble jujube polysaccharide against biofilm-forming oral pathogenic bacteria

Oral diseases caused by infectious pathogens raises significant concerns in public health. In the light of side effects of current antibiotics therapy and growing drug resistance of pathogenic bacteria, natural products have become attractive alternatives for antibiotics agents in dental practice. This current study investigated the effects of polysaccharides extracted from Zizyphus jujuba Mill. on three major oral biofilm-forming pathogenic bacteria including caries-inducing Streptococcus mutans, lesions-causing MRSA, and periodontitis-related Porphyromonas gingivalis, as well as general oral microbiota. Our results demonstrated that jujube polysaccharide prepared in this study was mainly composed by galacturonic acid with an average molecular weight 242 kDa, which were further characterized for structural features by FT-IR spectra and NMR spectroscopy analysis. This jujube polysaccharide was shown to exhibit remarkable inhibitory effects against all the tested oral bacterial pathogens through various mechanisms including growth inhibition, biofilm prevention and disruption, intervention of bacterial infection (adhesion and invasion), attenuation of cytotoxicity, modulation of excessive inflammatory response of LPS-stimulated and MRSA-infected macrophages as well as positive regulation of oral microbiota. The present study paves the way to explore jujube polysaccharides for the prevention and treatment of oral infectious diseases. Graphic Abstract.