In Vitro and In Vivo Antiplasmodial Activities, Phytochemical Characterization, and Acute Oral Toxicity of Leaf Extracts of Blumea balsamifera

Abstract

Blumea balsamifera is traditionally used in Thai herbal remedies for fever management; however, its antiplasmodial potential has not been comprehensively investigated. In this study, we evaluated the in vitro and in vivo antiplasmodial activities, phytochemical profile, and acute oral toxicity of B. balsamifera leaf extracts. Antiplasmodial activity against Plasmodium falciparum K1 and cytotoxicity against Vero cells were determined using the parasite lactate dehydrogenase (pLDH) assay and an MTT assay, respectively. Phytochemical constituents of the ethanolic extract were characterized by liquid chromatography–quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). In vivo antiplasmodial assessment was investigated in Plasmodium berghei ANKA-infected mice using Peters’ four-day suppressive test at oral doses of 200, 400, and 600 mg/kg. Acute oral toxicity was evaluated following a single oral dose of 2000 mg/kg. The ethanolic extract exhibited promising in vitro antiplasmodial activity, with an IC50 value of 2.65 µg/mL and a selectivity index (SI) of 23.03, whereas the aqueous extract was inactive (IC50 > 40 µg/mL). LC-QTOF-MS analysis of the ethanolic leaf extract tentatively identified 16 compounds in the negative ionization mode and 30 compounds in the positive ionization mode. In the four-day suppressive test, the ethanolic extract demonstrated dose-dependent antiplasmodial activity, with parasitemia suppression of 42.29%, 70.74%, and 76.54% at doses of 200, 400, and 600 mg/kg, respectively. In the acute toxicity study, no mortality, abnormal clinical signs, or significant changes in body weight, food consumption, or water intake were observed. Furthermore, no evidence of hepatotoxicity or nephrotoxicity was detected. The ethanolic leaf extract of B. balsamifera demonstrated antiplasmodial activity in both in vitro and in vivo models, with favorable selectivity and no apparent acute toxicity at the tested dose. These findings support the potential of B. balsamifera as a source of antiplasmodial compounds and provide a basis for further phytochemical isolation and mechanistic studies.