Phytochemical Evaluations, In-vitro Anti-sickling and Polymerization Inhibition Potentials of the Crude Methanol Leaf Extracts of Carica papaya LINN. and Psidum guajava LINN.

Abstract

Abstract 
The plants Carica papaya (Caricaceae) and Psidum guajava (Myrtaceae) are widely deployed in the management of sickle cell disease and the prevention of crisis by most care givers in north- eastern part of Nigeria. Other applications of the plants are in the management and treatment of diseases such as trauma, allergies, injuries, diabetic, cardiovascular diseases, strokes, colon cancer and in the treatment of malaria and typhoid fever. Due to their numerous medicinal applications, this paper focuses on the exploration of their qualitative and quantitative phytochemical constituents, antisickling and polymerization inhibition potentials of its leaf extract in an in-vitro system. The result of its qualitative evaluation revealed the presence of alkaloids, cardiac glycosides, flavonoids, tannins, terpenoids, phenolics, and saponins in Carica papaya while P. guajava extract tested positive for cardiac glycosides, flavonoids, tannins, terpenoids, phenolics, and Saponins both extracts are devoid of phlabotannins. Similarly, the metabolites are as follows; alkaloids (5.60), flavonoids (0.54), tannins (5.40), phenolics (1.56), and Saponins (2.80) in the methanol crude extract of C. papaya while P. guajava extract yielded the following percentage of constituents flavonoids (1.92), tannins (6.00), phenolics (8.25), and Saponins (4.00) respectively. Moreover, the in-vitro sickling inhibition studies revealed that the C. papaya 
extract most significantly inhibited sickling of the cells by up to 93.00% while, P. guajava crude extract acted in dose dependent manner with the highest inhibition of 77.89%. Likewise, the sickling reversal assay results revealed that C. papaya extract reversed the sickling by up to 97.14%while the crude extract of P. guajava acted in dose dependent manner with the highest reversal activity 
85.40%.Furthermore, the polymerization inhibition activity of 67.30% was revealed by C. papaya crude extract, while P. guajava crude extract revealed the most remarkable polymerization inhibition of up to 94.28% respectively. Hence, this study shows that the crude methanol leaf extract contained valuable phyto-constituents capable of inhibiting and reversing sickling ofHbSS cells in vitro, thus could be developed into prophylactic in the management of crisis in sickle cell patients.