European Journal of Medicinal Plants

Aims: “This work was to increase the production of secondary metabolites of P. odontadenius M2 using sodium azide (SA) in order to amplify those with in vitro antimalarial activity using Plasmodium falciparum strain K1”.

Study Design: Laboratory experiment tests; Immersion of seeds in SA concentrations; In situ culturing seeds, Harvesting plants M1; seeds M2 collected; Sowing of M2 seeds in to fields; Extraction of P. odontadenius aerial parts; Phytochemical screening, In vitro antiplasmodial testes to determine the inhibition of concentrations killing 50% of Plasmodium falciparum strain K1.

Place and Duration of Study: Department of Biology and Molecular Biology; General Atomic Energy Commission, Regional Center of Nuclear Studies, P. O. Box.: 868 Kinshasa XI, Democratic Republic of the Congo (DRC). The in vitro antiplasmodial activities conducted at the Faculty of Pharmacy, UMR-MD3, Aix-Marseille University, Marseille, France. The experiments were conducted firstly during August and December 2011; secondarily during May and September 2012 until July 2014.

Methodology: Seeds M2 from of Phyllanthus odontadenius M1 plants were obtained after oven drying at 45°C and they were immersed in SA at concentrations ranging between 0 to 20 mM. They sow in two fields (M2.1 and M2.2) and plants harvested after four months. In addition, some parameters such as height, collar diameter, number of branches and biomass from second generation (M2) were analysed. Phytochemical screening was released. The in vitro antiplasmodial activities assays on Plasmodium falciparum strain K1 was determined by ELISA HRP2.

Results: Results obtained showed that SA generally reduced the growth parameters such as heigth and colar diameter that reduce directly fresh biomass with the lowest reduction being -11.42% (10 mM SA) and the higher -22.37% (17.5 mM SA). Alkaloids were absents in the all samples. Tannins were present only in the extracts treated with 10 mM SA and anthocyanins, flavonoids and steroids/terpenoids were observed in all samples. For the in vitro antimalarial activities, better activities were observed for M2 extracts obtained from plants treated with 7.5 mM (3.26±0.05 µg/ml and 4.87±1.57 µg/ml) and 10 mM (4.52±0.12 µg/ml and 2.73±1.67 µg/ml) SA.

Conclusion: In conclusion, SA has, in general, negative effects on growth parameters of               P. odontadenius and enhances the in vitro antimalarial activity of P. odontadeius extracts.