Studies on the physicochemical and functional properties of alpha cellulose obtained from the stem of cocoyam (Colocasia esculentum) – A potential pharmaceutical excipient

This study investigates the stem of Colocasia esculentum (cocoyam) as a source of alpha cellulose. The a-cellulose, (ACC), was obtained by soda process with an average yield of 20 %. ACC was characterised for its physicochemical and functional properties. The physicochemical properties include organoleptic characteristics, identification, solubility, starch and dextrins, water-soluble substance and pH determinations. The flow properties of the powder were assessed by angle of repose, Hausner index, Carr's compressibility index and flow rate determinations. Other functional properties assessed include true density, particle size analysis, hydration and swelling capacities. Its functional properties were compared to those of Avicel PH101. The cellulose product, ACC, conformed to official specifications. The results of the physicochemical properties indicate good level of purity of the cellulose material. The moisture content was 9.8% and the true density was 1.67 g/ml, the hydration and swelling capacities were 1.86 and 140% respectively. The flow indices showed that ACC had a good flow. The functional properties indicate that ACC is comparable to Avicel PH 101 and is therefore a potential excipient in pharmaceutical tableting.