oa In-vitro Cytotoxicity Of Selected Sudanese Medicinal Plants With Potential Antitumor Activity

1.Introduction: According to unique position and varied climate, terrain, and flora and fauna, the Sudanese have developed a unique traditional culture. Their unique indigenous knowledge of herbs led to the development of numerous general health and preventative remedies. Some are useful and some, although widely accepted due to custom and tradition, proved harmful. Identification of medicinal plants with significant cytotoxic potential useful for the development of cancer therapeutics has gained increasing importance in the last decade and research in this field is expanding. Twenty five extracts of fourteen Sudanese plants, used traditionally as medicines, were previously screened for their safe use by the authors. Preliminary cytotoxicity and antioxidant activity investigations of these plants were carried out using Brine Shrimp Lethality Test (BSL), DPPH (1, 1-diphenyl-2-picrylhidrazil) radical scavenging and Iron Chelating Assays. Thirteen extracts showed significant cytotoxicity on BSL assay with different antioxidant capacities. Therefore, this study was conducted to evaluate the in-vitro cytotoxicity of these thirteen extracts in RAW 264.7 normal cell cultures to verify their traditional safe use and their potential antitumor capacity. Ethanol and aqueous extracts of Sesamum indicum, Acacia senegal, Moringa oleifera, Ambrosia maritima, the ethanol extracts of Nigella sativa and Foeniculum vulgare , the fixed oil of Riccinus communis and the essential oils of Piper nigrum and Coriandrum sativum were investigated. 2.Materials & Methodology: Three concentrations of the tested plants crude extracts were studied for their cytoxicity in normal cell cultures Raw 264.7 (125, 250 and 500 μg/mL), using Microculture Tetrazolium (MTT) cell viability assay to determine 50% inhibitory concentration. Cell inhibition percentages were also investigated using linear regression equation. 3.Results & Discussion: Traditionally, the tested plants have been used for the treatment of several diseases. In our study, two of the tested plant extracts showed significant cytotoxicity in normal cell cultures Raw 264.7. These were the ethanol extract of F. vulgarae which showed 67.86 % ± 0.03 cell inhibition at 125 μg/mL with IC50 1.3 μg/mL, while the aqueous extract of A. senegal showed 57.59 %± 0.09 cell inhibition at 125 μg/mL with IC50 23.5 μg/mL. The toxicity may be due to metabolic activation of chemical compounds of these two plant extracts. 4.Conclusions & Recommendations: The ethanol extract of F. vulgarae and the aqueous extract of A. senegal possessed cytotoxic activity to RAW 264.7 normal cell line at 125 μg/mL. Therefore, the data provide evidence that these extracts could potentially contain selective cytotoxic agents. The antitumor potential of these extracts for therapeutic attempts is considered. Further cytotoxic studied on different tumor cell lines must be carried out to verify the importance of these extracts for tumor therapeutics. The results agree with the ethno botanical use of the other tested plants extracts that had no activity to RAW 264.7 normal cell line. Investigation of active constituents of all extracts under study will provide useful comparative information before justifying their safe use.