Phytochemical profiling and in vivo antiplasmodium activity of fractionated Theobroma cacao bark extracts in Plasmodium berghei infected mice

Malaria remains a major public health concern, particularly in sub-Saharan Africa, owing to the emergence and spread of antimalarial drug resistance. This study investigated the phytochemical profile and in vivo antimalarial activity of Theobroma cacao bark extracts. Dried bark was successively extracted with n-hexane, ethyl acetate, and ethanol. The resulting extracts were fractionated by column chromatography and analysed using gas chromatography–mass spectrometry (GC–MS) and high-performance liquid chromatography (HPLC) to characterize their chemical profiles. Antimalarial activity was evaluated in Swiss albino mice infected with Plasmodium berghei using Rane’s test. Extracts were administered at doses of 100 and 500 mg/kg, with chloroquine (10 mg/kg) used as the positive control. Parasitaemia, percentage chemosuppression, parasite clearance time, packed cell volume (PCV), body weight, and survival time were assessed using standard procedures. The ethanol extract at 100 mg/kg demonstrated marked antimalarial activity, achieving 100% chemosuppression by Day 3 and complete parasite clearance by Day 5. The parasite clearance time differed significantly from that of the chloroquine-treated group (P < 0.05). However, the treatment did not result in prolonged survival compared with the control. GC–MS analysis identified fatty acid esters, phenolic compounds, and terpenoids, while HPLC profiling identified several flavonoids, with kaempferol constituting 62.87% of the extract. Treatment also improved PCV and reduced body weight loss compared with the control. These findings demonstrate the in vivo antimalarial activity of T. cacao bark extracts and their diverse phytochemical composition, supporting further investigation of their potential as sources of antimalarial compounds.