Gum arabic

About: Gum arabic is a research topic. Over the lifetime, 2197 publications have been published within this topic receiving 47782 citations. The topic is also known as: acacia gum.

Marketing of Acacia species (gum Arabic) in Borno state, Nigeria.

Abstract: The study examined the income distribution among Acacia spp (gum arabic) marketers in Borno state. Data were collected from 100 gum arabic marketers in 4 local government areas of Borno state through the use of structured questionnaire. Descriptive statistics, Gini-coefficient and regression models were used to analyse the collected data. The result of the analysis revealed that 71 % of the marketers were also farmers of some arable crops, and 64 % of them had 15 years and above experience in the gum Arabic marketing. The Gini-coefficient result showed that the gum arabic market in the state was concentrated and there was high inequality in the income distribution among the gum arabic marketers. The rate of return to scale (RTS) was 1.061, which implies that gum arabic marketing in the study area was in stage 1 of the production function. This means that allocation of resources for the marketing of gum arabic in the state was irrational.

Composition and structure of gum Arabic in solution and at oil-water interfaces

Abstract: Gum arabic, a tree exudate, is essentially used for its binding and emulsifying properties. This natural product is a complex mixture of covalently linked proteins and charged polysaccharides moieties, differing in their molecular mass and hydrophobicity. A large body of literature now exists on the structure and interfacial properties of gum Arabic but a comprehensive description of the relationship between interfacial composition, interfacial structuration and emulsion metastability remains elusive. In the literature, gum Arabic is described as a mixture of three fractions: an arabinogalactan rich polysaccharide fraction, a polysaccharide-protein conjugates fraction and a fraction of glycoproteins. The conjugate fraction is thought to be responsible for the emulsifying and stabilizing properties of the gum, with the protein part adsorbing at oil droplets surface and the carbohydrate moieties providing steric repulsion between droplets. In this work, we have investigated the microscopic behavior of the gum species in solution and at oil/water interfaces. The first step was to characterize the structure of gum Arabic species in solution. A twodimensional separation of the gum molecules was performed using size exclusion chromatography followed with by hydrophobic interaction separation, which confirmed the highly heterogeneous composition of the gum. Small angle X-ray and neutron scattering measurements on the gum and its fractions led us to propose a structural representation of the gum conjugated moieties. Then the composition of adsorbed gum Arabic films as compared to gum Arabic solutions has been investigated. An increase in the protein rate of the interfacial film showed the crucial role of the polypeptide moieties on the adsorption. The composition of the adsorbed film was shown to differ from the bulk but remained heterogeneous in size and hydrophobicity. A mass balance revealed a strong dependence between the emulsion formulation (gum concentration and physico-chemical parameters) and the surface concentration, while the composition of the interface was only slightly changed. These results suggest that gum Arabic adsorbing species must adopt conformational changes depending on emulsification conditions. In a third stage, we have addressed the stabilization mechanisms resulting from the adsorption of gum Arabic amphiphilic species. For that purpose, we have developed a method to recover the adsorbed species within an oil-in-water emulsion. This method allowed us to unveil a structuration of the adsorbed film. Species recovered from the interface displayed aggregation, the magnitude of which directly depended on the coverage density and protein rate of the adsorbed film. The metastability of emulsions, stabilized with gum Arabic, increased upon promoting interfacial structuration, i.e. when the aggregation rate of adsorbed species was enhanced. Such behavior has not been reported so far in the literature and we believe that it is a key mechanism of gum Arabic-based on emulsions. Finally, small angle neutron scattering experiments (contrast match between the continuous and dispersed phases) disclosed differences of structuration between two regimes of interface coverage. These observations were discussed in the light of the comparison with the scattering spectra of gum Arabic solutions. To conclude, this thesis revolves around the composition/structuration relationship in gum Arabic-stabilized emulsion stabilized and demonstrates that an original mechanism is at play in this complex system.

Evaluation of some physicochemical properties of Bombax gum

Abstract: Gum was extracted from the dried calyx of Bombax ceiba by two methods, hot and cold water processes. The gum obtained was subjected to some physicochemical tests using acacia gum for comparison. The hot water extract yielded more gum. The result of particle size distribution showed that 44.3% of hot water extract (HE), 30.4% of cold water extract (CE), and 49.3% of acacia gum (AC) were made of particles less than 150μm in size. Their packing and flow characteristics were evaluated and found as follows; bulk and tapped densities values were in order of AC > HE > CE, while Hausner’s Quotient was in the order of CE > HE > AC. Both HE and CE had Carr’s compressibility value above 40% while AC had about 27%.The packing fraction and porosity values for HE and CE were the same while their angle of repose measurements showed that HE > CE > AC. Their true densities were in order of AC > HE > CE. The hydration capacity of HE, CE and AC were 17.9, 16.7 and 4.7 respectively, while their swelling indices were 7.9, 7.6 and 2.8 respectively. HE, CE and AC had percentage fat content of 5.92%, 5.13% and 4.18%. The porosity of AC was 48%, while HE and CE had the same value of 87%. The relative viscosity of HE was found to approximately triple with every 0.9% increase in concentration, that of CE doubles while the viscosity of AC increases with about 0.2 units. These findings showed that the gum from Bombax ceiba possess interesting physicochemical properties that make it candidate for pharmaceutical use. Keywords: Bombax ceiba , packing and flow characteristics, hydration and swelling capacities, viscosities Journal of Pharmacy and Bioresources , Vol. 6 no. 2, pp. 38-42 (September 2009)