Gum from the bark of Anogeissius leiocarpusas a potential pharmaceutical raw material – granule properties

With the continuous effort to discover and produce cheap but high quality excipients for drug production Anogeissius leiocarpus gum (ALG), a brownish exudate obtained from the bark of Anogeissius leiocarpus a commonly occurring tree in Nigeria has been investigated for its potential as a binder in tablet formulation, by studying the properties of metronidazole granules prepared with it as binder. The properties of the resulting granules were compared with those of corn starch and poly vinyl pyrolidone (PVP) at various concentration levels. The granule elegance, mean particle size and particle size distribution, bulk, tapped and true densities, friability, angle of repose and compressibility (Carr's index) were determined and used to assess the gum relative to PVP and corn starch in granule formulation. Results of the various studies showed that lower concentrations of ALG produced granules that were quite comparable to those prepared with corn starch and PVP. However, higher concentrations of ALG produced granules that were comparatively different from those of corn starch and PVP. The optimal binding concentration of ALG lies within the concentration range of 1 – 3 % w⁄v. Anogeissius leiocarpus was found to have good binding potential for the formulation of Metronidazole granules. Key words: Anogeissius leiocarpus gum (ALG); Corn starch; PVP; Metronidazole; Granule properties Journal of Pharmacy and Bioresources Vol. 2 (1) 2005: 13-1

Synthesis, Physicochemical Characterization, And Functional Properties Of An Esterified Starch From An Underutilized Source In Nigeria

Acha ( Digitaria exilis Stapf), also known as Findi, Hungry rice, Petit mil and White fonio, is a small seeded cereal, indigenous to West Africa, which is generally classified as millet. It grows in various parts of Nigeria, Sierra Leone, Ghana, Guinea Bissau and Benin Republic. That species is the most important of a diverse group of wild and domesticated Digitaria species that are harvested in the savannas of West Africa. It is one of the primary cereals of southern Sudan and Ethiopia in Africa. It has potential to improve human nutrition, boost food security, foster rural development and support sustainable use of lands. In this study, acha starch was subjected to modification by acetylation. The acetylated acha starch with degree of modification 0.78 had reduced foaming capacity and amylose contents. The starches have similar organoleptic properties ranging from white, gritty, non sticky to bland tastes. Physicochemical indices investigated such as true density, bulk and tapped densities, water absorption capacity, moisture content, total and acid insoluble ash, and pH were reduced by the acetylation of acha starch. The modification resulted in a significant (P < 0.05) increase in the solubility as well as water and oil absorption capacities of the starch. Scanning electron microscopy revealed starch granules that were predominantly polygonal in shape. Acetylation did not alter the granule morphology. X-ray pattern of the native starch was A type, with similar pattern in the acetylated derivative. Fourier transform infrared spectroscopy (FTIR) results revealed a new band at 1728 cm-1. Thermogravimetry revealed 3 phase decomposition of both the native and modified starches. The acetylation as revealed by Differential scanning calorimetry studies improved the gelation capacity of the native starch and revealed two endothermic peaks and one exothermic peak each for both starches. There was considerable reduction in the peak temperature of gelatinization (Tp) of native starch and a significant (P<0.05) decrease in the enthalpy of gelatinization (DH) was noticed after acetylation