Effects of Acid treatment on the compression and mechanical properties of Xanthosoma Sagittifolium fibrous powder

Abstract

This study investigated the effect of acid treatment on the compression and mechanical properties of the cellulosic fibrous residue obtained after a high proportion of starch has been removed from the peeled and rasped tuberous root of Xanthosoma sagittifolium (Family: Araceae). Powdered fibrous residues were subjected to acid treatments at varying concentrations (0 – 0.4 M) of HCl and at varying time intervals. Treated samples were washed severally with water to obtain neutrality. The treated cellulosic residues were air dried to a moisture content of 3.5%. The resulting powders were characterized for flow, compression and mechanical properties. All determinations were carried out in triplicate and mean values with standard deviations were reported. Viscosity indices as measured by the time of flow (seconds) of mucilage showed a general decrease in viscosity with increase in acid concentration and duration of exposure. The densification of the powders as measured by Carr’s index and Hausner ratio showed an improvement in the compression properties after acid treatment with their values as 18.40 and 1.23 (untreated) and 8.31 and 1.09 (0.4 M HCl, 72 h) respectively. The porosity of the resulting powders was improved also by the acid treatment and the values were 0.549 (untreated) and 0.769 (0.4M HCl, 72 h). Acid treatment brought about remarkable improvement in the flow properties of powder with angles of repose of 27.80 ±1.08º (untreated) and 19.80± 1.25 º (0.4M HCl, 24 h). It was further shown that acid treatment of the fibrous residue resulted in a breakdown in the polymeric chain structure to simpler monomeric units which displayed better flow and compaction properties and may find useful applications as pharmaceutical excipients in tablet formulations.

Keywords: Xanthosoma sagittifolium powder, acid treatment, plastoelasticity, tensile strength, packing fraction, compaction, flow properties

Journal of Pharmaceutical and Allied Sciences, Vol. 10 No. 3 (2013)