Antiplasmodial and cytotoxicity evaluation of Artocarpus sericicarpus leaves extracts and fractions as a potential source of antimalarial substances

Malaria is one of the tropical diseases that become a health problem worldwide. The elimination of this disease faced various burdens, leading to the need for new antimalarial drugs. Based on the previously reported antimalarial activity of Artocarpus genus, Artocarpus sericicarpus has been selected as one of the candidates which are potential to be explored as a source of antimalarial substances. This study aimed to obtain active antimalarial fractions from A. sericicarpus leaves. Extraction of A. sericicarpus leaves was conducted by ultrasonic-assisted extraction using n-hexane, dichloromethane, and methanol as solvents. All extracts were tested for their antimalarial activity by Lactate Dehydrogenase (LDH) assay. The most active extract was fractionated by Vacuum Liquid Chromatography (VLC) and fractions were further tested by LDH assay as well. Cytotoxicity test conducted by resazurin assay on several cell lines to determine the active and nontoxic fractions which have the potential to be further purified and identified the active substances. The n-hexane, dichloromethane, and methanol extract showed antimalarial activity with IC₅₀ values of 23.96±0.06 µg/mL, 2.72±0.08 µg/mL, and 23.39±0.05 µg/mL, respectively. Dichloromethane extract was chosen for further separation due to its highest antimalarial activity. The separation was obtained in nine fractions. Fractions 2-9 had an IC₅₀ value of less than 10 µg/mL, indicating an active antimalarial substance. Meanwhile, fraction 1 has moderate antimalarial activity. Cytotoxicity test results considered all fractions to be non-toxic. The TLC profile of dichloromethane extract identified polyphenolic compounds, suggesting the active polyphenolic compounds can be further isolated from the active fractions (F2-F9).