Citrus sinensis peel pectin: A novel binder in erythromycin tablet formulation

Abstract

The aim of this study was to comparatively evaluats Citrus sinensis peel pectin as a pharmaceutical excipient (binder) in erythromycin tablet formulation. The orange peel pectin was extracted from the peel of Citrus sinesis, dried, milled and the phytochemical constituents determined. Erythromycin granules were formulated employing the milled pectin as well as acacia and corn starch, as binder and the granules evaluated for micromeritic properties. The granules were compressed to tablets at the compression pressure of 30N/m² and the tablets evaluated for hardness, friability, disintegration time, dissolution profiles and release kinetics. The extracted orange peel pectin was found to contain flavonoids, carbohydrates and reducing sugar. However, alkaloids, anthraquinone, saponin, cardiac glycoside, terpenoid and tannin were found to be absent. The different batches of formulated erythromycin granules were free flowing with angle of repose between 20.07 ± 3.74 to 20. 82 ± 1.51^o., bulk density (0.43 ± 0.03 to 0.53 ± 0.02 g/ml); tapped density (0.51 ± 0.05 to 0.61 ± 0.03 g/l); compressibility index (8.12 ± 3.57 to 13.93 ± 6.20); Hausner’s ratio (1.14 ± 0.07 to 1.25 ± 0.19) and flow rate (0.55 ± 0.11 to 0.94 ± 0.13 m/s). All formulated erythromycin tablets were uniform in weight. Their hardnesses were satisfactory (4.5 ± 0.02 to 6.7 ± 0.05 kg/cm²) as well as friability (0.40 ± 0.12 to 0.91 ± 0.10%). Most of the tablets disintegrated within 15 minutes, except those formulated with 10% of the binders with acacia 10% ^w⁄_v (20.1 ± 0.02 minutes), corn starch mucilage (CSM) 10% ^w⁄_v (21.4 ± 0.03) and orange peel pection (OPP) 10% ^w⁄_v (25.4 ± 0.05 minutes) respectively. Increase in the binder concentration resulted in a corresponding increase in hardness and disintegration time, but decrease in percentage friability. The dissolution of all batches of erythromycin tablets fitted into the Higuchi model release kinetics. Orange peel pectin exhibited good binding property comparable to those of the standard acacia and corn starch mucilage.