Harnessing Indonesian natural products against neglected tropical diseases: Malaria

The Indigenous peoples of Indonesia possess a long-standing tradition of combating tropical infectious diseases, particularly malaria. Over generations, extensive ethnobotanical knowledge on the use of tropical medicinal plants to alleviate Plasmodium-induced fever has been developed and transmitted.

This review aims to compile comprehensive information on Indonesian medicinal plants with antimalarial potential and to elucidate their bioactive constituents and pharmacological activities in response to the growing challenge of antimalarial drug resistance.

A comprehensive review of ethnopharmacological documentation on Indonesian antimalarial plants was conducted using four databases: (1) an ethnopharmacological survey resulting from a collaboration between Eisai Ltd. and the Ministry of Health of the Republic of Indonesia; (2) a recent ethnopharmacological report published by the Ministry of Health; and two scientific databases, (3) SciFinder and (4) Garuda, employing the keyword ethnopharmacology. Subsequent searches for phytochemical and antimalarial studies were performed using SciFinder and Garuda with the keywords antimalarial, antiplasmodial, and Indonesia, yielding a total of 126 relevant publications.

Among 208 medicinal plants with reported antimalarial activity, 99 crude extracts and fractions derived from 61 species were evaluated against various Plasmodium falciparum strains. Seventeen plant species have undergone detailed chromatographic isolation, yielding 146 structurally diverse compounds. Notably, several compounds exhibited potent anti-plasmodial activity at the nanomolar level, including samaradine X (94), norcaesalpinins E (119), methyl 15-acetoxylansiolate (88), and dehatrine (29), with IC₅₀ values of 14, 90, 170, and 170 nM, respectively (chloroquine IC₅₀ = 290 nM).

These results highlight the significant potential of Indonesian medicinal flora as sources of new antimalarial agents. Further in-depth phytochemical and pharmacological investigations are warranted to identify additional bioactive constituents from these underexplored plant species.