Investigation of antibacterial activity of new bionanocomposite based on polyvinyl alcohol(PVA)/arabic gum(AG)/MgO nanoparticles by Taguchi design for mouthwash application

Untreated dental caries is an important word challenge in human life. In this work, we synthesized polyvinyl alcohol-gum arabic-magnesium oxide nanoparticles new bionanocomposite and evaluated the antibacterial properties of its against Streptococcus mutans biofilm in vitro. For optimization of variables to have the maximum antibacterial property, L9 orthogonal array of Taguchi method was used for design of extraction conditions. The nanocomposites were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray energy diffraction (EDS), Thermogravimetric analysis (TGA) and transmission electron microscopy (TEM) tests. The FESEM images of nanocomposite inhibit that the nanoparticles are entirely surrounded with polymers chains of matrix and nanoparticles are deposited on the its walls, thus a layered nanocomposite is formed. The sheet width and size range of the nanocomposite was determined between 30-40 and 20-90 nm, respectively. The results showed that the synthesized nanocomposite with conditions of 1 mg/ml PVA, 3 mg/ml AG, and 6 mg/ml MgO (experiment 3), had the strongest antibacterial activity against the Streptococcus mutans bacteria’s biofilm. In this condition, the bacterial survival rate was the lowest at 0.21 CFU/ml and under this optimal conditions could inhibit the activity of Streptococcus mutans bacteria at a rate of 0.09 CFU/ml.