Evaluation of the Emulsifying Properties of Grewia Sp

Abstract

Polysaccharide gums derived from Grewia spp, a medicinal plant of the Malvaceae family are reportedly useful as excipients in different pharmaceutical formulations. In this study, we investigated and evaluated the emulsifying property of this gum extract by comparing with acacia gum as an emulsifying agent in the formulation of metronidazole emulsion. First, Grewia gum was extracted from pods and characterized. Six formulations of metronidazole emulsion were then prepared from Grewia or acacia gum. Next, the emulsions were evaluated and observed for creaming index, phase separation, viscosity, pH and organoleptic properties. Study showed emulsion from Grewia gum to exhibit lower creaming index than those of acacia or a combination of both. They however showed higher viscosity than those from acacia or combination of both gums with no apparent change(s) in colour, odour and appearance throughout the period of storage. Also, the pH value of acacia emulsions proved acidic just as the Grewia gum. The gum showed a pH of 6.15 with excellent flow property. The study showed the physiochemical properties of the gum to be good and employable in the pharmaceutical industry as a stabilizer, thickener especially when high viscosity is required. Further studies that corroborate this work is recommended.