Gel containing mangosteen peel extract against Helicobacter pylori

Abstract

Abstract

Helicobacter pylori is a micro-aerophilic, Gram-negative bacterium living in the human gastric mucosa that has a strong association with chronic active gastritis and duodenal ulcer (DU). The objective of this study was to test antimicrobial activity of mangosteen pericarp extract against H. pyroli and to develop mucoadhesive gel as a drug reservoir for a mangosteen crude extract. Broth microdilution method was used to determine antibacterial activity of ethyl acetate, methanol, hexane and aqueous extracts. Oral gels were combination between two polymers (sodium carboxymethylcellulose (SCMC), hydroxypropyl-methylcellulose (HPMC) or sodium alginate) at different ratio. All formulations were immersed in simulated gastric fluid, phosphate buffer pH 6.8 and deionized water in order to test their stability. Results from 96-well plate revealed that ethyl acetate, methanol and water extracts showed minimum inhibitory concentration (MIC) at 0.3125 mg/ml whereas hexane extract has MIC higher than 10 mg/ml. MICs of metronidazole and ampicillin were 0.156 mg/ml and 31.25 mg/ml, respectively. In the gastric fluid, syneresis was observed in gel in formulations 1-8 whereas there were no changes in formulation 9-12. However, Formulation 9-12 had low viscosities. Therefore, formulation 8 was chosen because of its property and appropriate viscosity and clarity. Since aqueous extract was quite safe, it was selected for further development. In addition, its stability in aqueous medium would be considered.