The in vitro antisickling effect of purified alkaloids of Cremaspora triflora (Thonn.) K. Schum. (Rubiaceae) and Macaranga schweinfurthii Pax. (Euphorbiaceae)

Abstract

Introduction and objective: Sickle cell disease is an inherited pathology to an abnormality of hemoglobin precisely hemoglobin S for which there is no curative therapy. It mainly affects sub-Saharan African and Caribbean populations. Thus, this study aims to make the phytochemical screening of Cremaspora triflora and Macaranga schweinfurthii as well as to evaluate the antisickling activity of their purified alkaloids. Methodology: Chemical screening was performed using color and precipitation tests as well as the foam index method. The extraction of the alkaloids was carried out with organic solvents in a basic medium while the purification by open column chromatography. The evaluation of the antisickling activity was carried out by Emmel’s test. Results: The chemical screening highlighted alkaloids, steroids, saponins, tannins, and terpenoids in the species studied. Flavonoids and anthocyanins were present in organs of Macaranga schweinfurthii, but absent in Cremaspora triflora. The extraction showed that Macaranga schweinfurthii leaves contained 0.59% alkaloids and 0.73% alkaloids in Cremaspora triflora leaves. The alkaloids purification allowed to obtain an alkaloidal fraction MS1 (1.24 g, 70.05%) from Macaranga schweinfurthii and two fractions [CT2 (0.934 g, 63.97%) and CT3 (0.006 g, 0.41 %)] from Cremaspora triflora which tested positive with Dragendorff and Wagner reagents. The antisickling activity evaluation showed that the SIR varied between 36.00% (0.25 mg/ml) and 90.66% (1 mg/ml) for the alkaloid solutions of Cremaspora triflora (IC50 of 0.51 mg/ml) as well as between 4.00% (0.25 mg/ml) and 33.33% (1 mg/ml) for the alkaloid solutions of Macaranga schweinfurthii (IC50 of 1.40 mg/ml). Conclusion: This study showed that the purified alkaloids of the studied plant species have an inhibitory power on sickling.