Phytochemical Screening and Synergistic Anti-proliferative Activity against Selected Cancer Cell Lines of Moringa oleifera and Indigofera arrecta Leaf Extracts
Jecinta Wanjiru Ndung’u
Department of Biochemistry, Rongo University, P.O.Box 103-40404, Rongo, Kenya and Centre for Traditional Medicine and Drug Research, Kenya Medical Research Institute, P.O.Box 54840-00200, Nairobi, Kenya
Edward Anino
Department of Biochemistry, Rongo University, P.O.Box 103-40404, Rongo, Kenya
Douglas Kahura Njuguna
Department of Biochemistry and Molecular Biology, Egerton University, P.O.Box 536, Egerton, Kenya
Reginah Mwangangi
Department of Biochemistry and Biotechnology, Kenyatta University, P.O.Box 43844-00100, Nairobi, Kenya
Mercy Jepkorir
Department of Chemistry and Biochemistry, Laikipia University, P.O.Box 1100, Nyahururu, Kenya
Regina Wachuka Mbugua
Centre for Traditional Medicine and Drug Research, Kenya Medical Research Institute, P.O.Box 54840-00200, Nairobi, Kenya and Department of Biochemistry and Biotechnology, Kenyatta University, P.O.Box 43844-00100, Nairobi, Kenya
Jean Chepng’etich
Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, P.O.Box 62000-00200, Nairobi, Kenya
Chrispus Mutuku Ngule
Centre for Traditional Medicine and Drug Research, Kenya Medical Research Institute, P.O.Box 54840-00200, Nairobi, Kenya and Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, P.O.Box 62000-00200, Nairobi, Kenya
Peter Mwitari *
Centre for Traditional Medicine and Drug Research, Kenya Medical Research Institute, P.O.Box 54840-00200, Nairobi, Kenya
*Author to whom correspondence should be addressed.
Abstract
Medicinal plants present a plausible source for anticancer agents. Combination of plant extracts and plant-derived compounds with the currently used cancer drugs has shown a marked improvement of the conventional drugs' efficacy and reduced toxicity. This study evaluated; phytochemical screening, antiproliferative activity and drug interaction potentials of Moringa oleifera and Indigofera arrecta leaf extracts with 5-fluoro uracil against selected cancer cell lines. Phytochemical screening was done using standard procedures. The common 3– (4, 5-dimethylthiazol-2-yr) -2, 5-diphenyltetrazolium (MTT) assay was used to determine the growth inhibitory potential of the extracts towards cancer cells. Drug interaction assays were done using constant ratio combination method. Alkaloids, terpenoids, tannins, flavonoids, glycosides, phenols and saponins were found to be present in the plant's extracts. M. oleifera and I. arrecta methanol-dichloromethane extracts had the highest activity compared to water extracts. All the extracts showed antiproliferative activities towards; HCC 1395 (breast), DU145 (prostate) and Hela (cervical) cancer cell lines. The extracts were not cytotoxic towards Vero cells (IC50>1000 µg/ml). I. arrecta and M. oleifera inhibited DU145 the most with IC50 values of 111.110 µg/ml and 66.290 µg/ml respectively. The plant extracts synergistically inhibited the growth of cancer cells (CI<1). Combination of the plant extracts and 5-Fluorouracil depicted that the concentration of the conventional drug could be reduced and yet achieve the same desired effect against cancerous cells (Dose reduction index (DRI) >1). Further studies to isolate the bioactive compounds and deduce the probable mechanisms of action are recommended.
Keywords: Anti-proliferation, cytotoxicity, phytochemical, Moringa oleifera, Indigofera arrecta