We investigated the antiplasmodial properties of crude extracts from Carica papaya leaves to trace the activity through bioassay-guided fractionation. The greatest antiplasmodial activity was observed in the ethyl acetate crude extract. C. papaya showed a high selectivity for P. falciparum against CHO cells with a selectivity index of 249.25 and 185.37 in the chloroquine-sensitive D10 and chloroquine-resistant DD2 strains, respectively. Carica papaya ethyl acetate extract was subjected to bioassay-guided fractionation to ascertain the most active fraction, which was purified and identified using high-pressure liquid chromatography (HPLC) and GC-MS (Gas chromatography-Mass spectrometry) methods. Linoleic and linolenic acids identified from the ethyl acetate fraction showed IC50 of 6.88？μg/ml and 3.58？μg/ml, respectively. The study demonstrated greater antiplasmodial activity of the crude ethyl acetate extract of Carica papaya leaves with an IC50 of ？μg/ml when compared to the activity of the fractions and isolated compounds. 1. Introduction Carica papaya L. of the family Caricaceae is a soft-stemmed perennial plant. It is usually unbranched and can grow to a height of about 20？m [1]. It is believed to originate from the Caribbean coast of Central America and over the years has found its way into many tropical and subtropical climates [2]. C. papaya can grow in male, female, or hermaphrodite forms. It is found growing wild in many parts of the tropics and is cultivated because of its sweet juicy fruit which serves as a nutritious food with rich medicinal value and also because of the ease with which it is digested. It commonly features in breakfasts, cooked in diverse ways, and as ingredients in jellies beverage and juice [3]. The fruits, leaves, and latex of this species are traditionally used in different parts of the world to treat diverse disease conditions. It is used in various places in the treatment of asthma, rheumatism, fever, diarrhea, boils, and hypertension and to increase the production of milk in lactating individuals [4]. Previous studies have shown that this species has promising antifungal [5], antibacterial [6], and anthelminthic [7] properties. However, studies on the in vitro antiplasmodial and cytotoxic properties of crude extracts sequentially extracted from solvents of different polarities are nonexistent in the literature. In this study, Carica papaya leaves were sequentially extracted with petroleum ether, dichloromethane, ethyl acetate, methanol, and water in that order. The antiplasmodial and cytotoxic activities of the extract
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