Kehinde Ajayi

Nigeria

Oil of Azadirachta indica Seed inhibited Plasmodium falciparum dihydroorotate dehydrogenase (PfDHODH) in vivo and in silico studies

Kehinde Oluyemi Ajayi 1, Olumide Oluyele2
1. Department of Natural Science (Microbiology), Precious Cornerstone University, Ibadan, Nigeria
2. Department of Microbiology, Adekunle Ajasin University, Akungba-Akoko, Nigeria

Abstract

Background

Malaria remains the oldest human enemy in sub-Sahara Africa and has been a human disease of major importance throughout history. This study investigates the chemical composition and antiplasmodial potential of Azadirachta indica (A. Juss) seed essential oil using in vivo and in silico approaches.

Methods

The extraction of the essential oil was carried out using hydro-distillation
Soxhlet extraction method and bioactive components were examined using Gas
Chromatography – Mas Spectrophotometry (GC-MS). The identified bioactive compounds
was docked against Plasmodium falciparum dihydroorotate dehydrogenase (PfDHODH) and
validated using in vivo prophylactic and curative effects in Plasmodium berghei (NK65)
infected Swiss albino mice.

Results

Gas Chromatography-Mass Spectrometry (GC-MS) analysis
revealed fifteen compounds, with Eugenol (18.64%), Thymol (15.72%), and Bornyl acetate
(13.17%) as the most abundant. In silico docking studies identified Thymol as having the
strongest binding affinity PfDHODH (-7.364 kcal/mol) compared to the standard drug
Malarone (-5.854 kcal/mol). During in vivo prophylactic and curative assays, the oil
demonstrated 100% chemosuppression at 3 mL/kg of oil.

Conclusions

The bioactives in essential oil of A. indica, particularly Thymol, shows promise as an alternative antimalarial agent.