Characterization of Potential Plant Growth Promoting Rhizobacteria Isolated from Maize ( Zea mays

Our study aims to characterize Plant Growth Promoting Rhizobacteria (PGPR) isolated from maize roots in five agroecological zones of central and northern Benin. Sixty samples were collected at the rate of four samples per village and three villages per agroecological zone. Rhizobacteria strains were isolated from these samples and biochemically characterized. These strains were analyzed for some of their PGPR traits like ammonia production and hydrogen cyanide following conventional methods. Microbiological investigation of these samples has shown that maize rhizospheres in central and northern Benin contain a high diversity of microorganisms. A total of nine species of maize Plant Growth Promoting Rhizobacteria were identified. Those PGPR include five Bacillus species (B. polymyxa, B. pantothenticus, B. anthracis, B. thuringiensis, and B. circulans), three Pseudomonas species (P. cichorii, P. putida, and P. syringae), and Serratia marcescens. The microbial diversity does not depend on the soil types. The microbial density, generally high, varies according to both soil types and agroecological zones. All Serratia strains (100%) have produced ammonia, whereas 80% of Bacillus and 77.77% of Pseudomonas produced this metabolite. The hydrogen cyanide was produced by all isolates (100%) independent of their genus. These results suggest the possibility to use these rhizobacteria as biological fertilizers to increase maize production

The aqueous extract of the root bark of Psorospermum febrifugum Spach effectively corrects anaemia. Experimental study on Wistar rats

Objectives: Psorospermum febrifugum Spach. (Clusiaceae) is a medicinal plant found in Africa. It root bark was used in Benin to treat anaemia. This work aimed to study the therapeutic efficacy of that root bark extract on anaemia treatment.Methodology and Results: Wistar Rats were anaemic by intraperitoneal injection of phenylhydrazine chloridrate. The rats were then fed either with Psorospermum febrifugum Spach root bark extract at 200 or 300 mg / kg weight / day, or with vitafer® as the reference drug. Non-anaemic rats served as controls. The blood count and osmotic resistance of red blood cells carried out on blood samples of rats at different days (D0, D2, D7, J10 and D15) showed a correction of anaemia with the extract in two weeks. The extract screening revealed saponosides, reducing sugars, polyphenols, flavonoids, tannins, proteins, anthocyanins and alkaloids.Conclusion and application of results: The extract completely corrected anaemia in two weeks by increased stimulation of hemoglobin synthesis and the production of young red blood cells released into the blood. Its effect seems dose-dependent and at the 300 mg / Kg dose was even more effective than the vitafer. This remarkable efficiency would certainly be linked to its chemical composition, whose elements would act in an isolated or synergistic way to stimulate haematopoiesis.. In addition, the extract had no effect on blood thrombocytes suggesting a certain specificity of action on the erythrocyte line. Psorospermum febrifugum Spach root bark had an excellent therapeutic efficacy and could be a good candidate for transformation into improved traditional medicines (ITM) for anaemia treatment, after acute and chronic toxicity tests and appropriate clinical trials.Keywords: Psorospermum febrifugum Spach, anaemia, osmotic resistanc