In-vitro antisickling and sickling-reversal activities of Carica papaya fruit at different stages of ripening

Objective: Sickle cell disease (SCD) is a haemoglobinopathy that causes several clinical complications. Unripe Carica papaya has been shown to possess antisickling activity that could reduce these complications. This study aimed to examine the presence of antisickling and sickling-reversal activities of aqueous extracts and ethyl acetate fractions of C. papaya fruit at different stages of ripening. Methods: Unripe, partly ripe, and fully ripe fruits were quantitatively screened for some phytochemicals using standard methods. Blood samples from sickle cell patients were used to investigate antisickling and sickling reversal activities of aqueous extracts and ethyl acetate fractions of the fruits. Data were analysed using one-way ANOVA. The p-value was set at 0.05. Results: Phytochemicals such as alkaloids, saponins, tannins, flavonoids and polyphenols were found in varying concentrations in C. papaya fruit at the different stages of ripening. All extracts and fractions showed antisickling and sickling-reversal activities with the ethyl acetate fraction of partly ripe C. papaya being most effective.  Conclusion: The study showed that C. papaya fruit at different stages of ripening contains antisickling and sickling-reversal activities which may help reduce the associated complications of SCD when consumed by affected individuals.