Total Alkaloid Content and β-hematin Inhibitory Potential of a Hepta-herbal Agboiba Antimalarial Decoction

Abstract Malaria, one of the deadliest diseases in the world is most prevalent in tropical and sub-tropical regions where medicinal plants are frequently used for its management. Given that medicinal plants play a significant role in the treatment of malaria, mechanistic studies are needed in order to validate their efficacy as well as for their optimization. In the current study, the total alkaloid in a hepta-herbal Agbo-iba (HHA) extract used as traditional decoction for managing malaria in Benin City, Nigeria was quantified. Furthermore, its ability to inhibit β-hematin formation was conducted in vitro. The alkaloidal content and β-hematin inhibitory potential of Annickia affinis; one of HHA’s constituent plants was also investigated alongside. HHA with a β-hematin inhibitory potential of IC50 = 88 µg/ml, possessed an alkaloidal content of 5.9 %w/w whereas, A. affinis decoction inhibited β-hematin formation by IC50= 60 µg/ml and possessed an alkaloidal content of 81 %w/w. A. affinis with an ~14-fold higher alkaloidal content is thus only ~1.5-fold better at inhibiting β-hematin formation than HHA. These results suggest that other plants aside from A. affinis may be contributing to HHA’s β-hematin inhibitory ability. Future mechanistic studies should investigate all HHA’s constituent plants alongside the hepta-herbal so as to reveal their contributions. Keywords: Alkaloids, β-hematin, Hepta-herbal Agbo-iba, Synergy, Malaria