Phytochemical Analysis and Evaluation of Anticancer and Antimalarial Properties of Four Medicinal Plants

Abstract

Cancer and malaria are among the most life-threatening diseases globally. Cancer is responsible for about 125,000 annual deaths globally. In 2015, the World Health Organization report estimated that 236000-635000 people died of malaria. These diseases are complicated by the development of resistance to available chemotherapeutic agents. Natural products have been recognized for their major applications in the identification of drug leads in drug discovery. Viola philippica Car, Viola yedoensis Makino (Violaceae), Triclisia subcordata Oliv (Menispermeaceae) and Cyclicodiscus gabunensis Harms (Fabaceae) are medicinal plants traditionally used for the treatment of various diseases including malaria or cancer in China and West Africa. However, the bioactive compounds are unknown. Therefore, this study evaluated the in vitro anticancer and antimalarial activities of the four medicinal plants and searched their bioactive compounds. The in vitro anti-ovarian cancer and antimalarial assays were demonstrated respectively using sulforhodamine B dye and Syber green 1 fluorescence assay methods. Bioassay-guided fractionation and purification were performed. Structural elucidation was performed by nuclear magnetic resonance spectroscopy and mass spectrometry analysis. Results revealed the anticancer and antimalarial activities of T. subcordata; V. philippica, and V. yedoensis to be bisbenzylisoquinoline alkaloids (cycleanine, isochondodendrine and 2'-norcocsuline) and/or cyclotides. The cycleanine analogues were synthesized and found to be more potent than cycleanine. Induction of apoptosis by these alkaloids has also been determined. This study could serve as basis for the support of use of these plants in cancer and/or malaria treatment. The BBIQ alkaloids and analogues could serve as lead compounds in drug discovery. Future in vivo studies need to be carried out on these alkaloids to get drug approval.