Evaluation of the sweetening effects of thaumatococcus daniellii fruits in metronidazole syrup formulations

Abstract

Organoleptic properties affect the acceptability of pharmaceuticals and patient compliance; many manufacturers argue that improving the palatability of liquid medicines with sucrose improves patient compliance. Chronic administration of sweetened liquid medicines increases the risk for dental caries and gingivitis in children and additional calories in adults. However, natural sweeteners could be non-toxic, non-caloric and non-cariogenic. This study aims at evaluating the degree of sweetness imparted by the sweet protein; Thaumatin, extracted from the arils of the fruit of Thaumatococcus daniellii (TD), in masking the bitter taste of Metronidazole. Syrup BP was used as a reference. The fruits of TD was dried and pulverized. An extract was obtained from the arils of TD by aqueous extraction. Viscosity, pH and flow rate of the extract were determined. Metronidazole oral syrup was formulated using either the extract or Syrup BP as the syrup base. The formulations were evaluated based on their organoleptic properties of taste, odour, colour and clarity as well as physicochemical properties such as flow rate, pH and viscosity. The extract was slightly acidic and has a viscosity of 16 ± 0.95 cP while syrup BP had a viscosity of 37 ± 1.65 cP at 100 rpm. The formulations containing Thaumatin extract had sweeter and longer lasting sweetness than formulations with Syrup BP. Formulation containing the extract had a faint odour that was pleasant while Syrup BP formulation was odourless. The extract imparted better sweet taste and acceptable organoleptic properties to Metronidazole liquid formulations than Syrup BP.