Showing papers by "Abdou Moumouni University published in 1998"
TL;DR: The total antioxidant capacity of the aqueous extracts was relatively high, indicating that the wild plants of the western Sahel may contain substantial amounts of water-soluble flavonoid glycosides, which are potent antioxidants and have been shown to have anticancer properties.
85 citations
Abstract: Within the framework of the IDAF (IGAC DEBITS AFRICA) network, we present in this paper data on precipitation and aerosol chemistry in the semiarid savanna of the Sahelian region of Niger. An automatic wet-only precipitation collector was operated at the Banizoumbou station during the entire 1996 rainy season (June to September 1996). Inorganic (Na+, NH4+, K+, Mg2+, Ca2+, Cl-, NO3-, SO42-) and organic contents of the precipitation (HCOOH, CH3COOH, C2H5COOH) were determined by Ion Chromatography (IC) in 29 rainfall events. Once per week, bulk particle samples were collected on the same site, and soluble water material was determined by IC. We examined the influence of atmospheric gas and particle sources on the precipitation and aerosol chemical contents. We established the influence of marine, terrigenous, and biogenic sources in the Sahelian region. The terrigenous signature is dominant and related to Sahelian soil erosion, with a high calcium content in precipitation (31.2 μeq L-1) and in aerosols (1.8 μg m-3). Two other signatures of atmospheric sources are highlighted by the relatively high nitrogenous (ammonium and nitrate) and organic contents (formate, acetate) in the precipitation. Ammonium (12.9 μeq L-1) and nitrate (12.3 μeq L-1) contents confirm respectively the biogenic source of ammonia released by domestic animal excreta in Niger and the natural emissions from semiarid savannas soils, perturbed by wild or domestic animal grazing. In spite of a high potential acidity given by nitrate, formate and acetate; a weak acidity (H+ (2.1 μeq L-1) is calculated from the mean pH of 5.67 measured. A statistical analysis of the aerosol chemical composition clearly indicates that nitrates are strongly correlated at the 1% level with terrigenous ions, i.e., Ca2+ and Mg2+ (0.95 < r < 1). We observed a similar relationship between all the terrigenous ions and nitrate in the precipitation. In the Sahelian region, alkaline soil dust representative of the terrigenous contribution interact, with gaseous nitrogenous and carbonaceous compounds, leading to the neutralization of acid gases and subsequent weak acidity in precipitation. Finally, taking into account the main chemical characteristics of Banizoumbou precipitations and aerosols, which demonstrate the importance of heterogeneous and multiphase chemical processes, we propose a conceptual model of the atmospheric chemistry in the Sahelian region.
68 citations
TL;DR: To improve sauce adhesion to the dried meat, wheatflour was added to the traditional sauce (a mixture of groundnut paste, water, and spices) and optimized the kilishi processing to improve product yield.
25 citations
TL;DR: A precocious weaning showed that the highest growth rate and protein efficiency ratio (PER) can be obtained by feeding the larvae rotifers in association with a dry diet, and the best PER and protein productive value (PPV) were recorded with feeding sequences R2 and R5.
Abstract: The suitability of the freshwater rotifer Brachionus calyciflorus as starting food for the larviculture of African catfish, Clarias gariepinus Burchell, was investigated through studies of growth and fatty acid profiles in relation to different feeding sequences combining live food and dry diet in various proportions and during different mixed feeding periods. The best results for survival were observed when rotifers were supplied during the first week of feeding, i.e. sequences R2 (exclusive supply of rotifers, then dry diet from day 8, onwards) and R5 (50% rotifers+50% dry diet until day 7, then dry diet 100%), reaching 99.2% and 96.3%, respectively. The specific growth rate of larvae was largely dependent on the duration of preliminary feeding with the rotifers. A feeding with rotifers as a unique food source did not produce satisfactory growth during the first week of feeding. A precocious weaning showed that the highest growth rate and protein efficiency ratio (PER) can be obtained by feeding the larvae rotifers in association with a dry diet. The best PER and protein productive value (PPV) were recorded with feeding sequences R2 and R5. On the other hand, the series of polyunsaturated fatty acids was characterized by a relatively constant concentrations, and represented about 11.6% of the total fatty acids in sequence R2 because of the presence of the acids of the linoleic series, which apparently originated from the food. The R5 regime provided larvae with significant amounts of highly unsaturated fatty acids, such as linolenic acid C18:3n-3.
20 citations
TL;DR: An electrophoretic comparison of variation at 32 isozyme loci was performed for 122 Vigna vexillata and 3 V. lobatifolia accessions, finding some similarities between the organization of the gene pools of V. vexillATA and V. unguiculata have been found.
14 citations
TL;DR: An electrophoretic comparison of variation at 30 isozyme loci was performed for 45 accessions from genus Vigna, section reticulatae and these results fitted the nomenclature used.
13 citations