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Introduction: Plants from Kenyan flora are traditionally used to manage a number of ailments including; chronic and infectious disease, to bolster the body immunity and for general health protections. The current investigation was designed to validate the quality with respect to the pharmacological significance of 156 fresh plant materials resulting from 27 ethno-medicinal plants, from Ngong forest, Kenya. Materials and Methods: Pharmacological screening was carried out using the field deployable GIBEX Screens- To-Nature (STN) validated assays. The plant extracts were screened for antifungal; general protozoal lethality; round worm lethality and antioxidant potential. Results: Different plant parts exhibited a range of activities; related to their traditional uses; with eleven out of twenty-seven extracts exhibiting highest activities in only one out of four categories of assays studied. All plant parts of only one plant C. axillaris exhibited high activities in all (4/4) the categories of assays evaluated. The other plants that exhibited high activities in three out of four (3/4) categories of assays studied included; A. oppositifolia, B. huillensis and T. trichocarpa. Conclusion: The current investigation provided additional data in relation to the usefulness of the studied ethno-medicinal plants, mostly of the following plants; C. axillaris, A. oppositifolia, B. huillensis and T. trichocarpa in the management of diseases that are infectious and to bolster the immunity. The reported data will contribute towards authenticating the claimed traditional use of these plants. The extracts that exhibited high activities should be investigated further to determine their effective concentrations. [ABSTRACT FROM AUTHOR]

Background: While incidences of cancer are continuously increasing, drug resistance of malignant cells is observed towards almost all pharmaceuticals. Several isoflavonoids and flavonoids are known for their cytotoxicity towards various cancer cells., Purpose: The aim of this study was to determine the cytotoxicity of isoflavones: osajin (1), 5,7-dihydroxy-4'-methoxy-6,8-diprenylisoflavone (2) and biflavonoids: chamaejasmin (3), 7,7″-di-O-methylchamaejasmin (4) and campylospermone A (5), a dimeric chromene [diphysin(6)] and an ester of ferullic acid with long alkyl chain [erythrinasinate (7)] isolated from the stem bark and roots of the Kenyan medicinal plant, Ormocarpum kirkii. The mode of action of compounds 2 and 4 was further investigated., Methods: The cytotoxicity of compounds was determined based on the resazurin reduction assay. Caspases activation was evaluated using the caspase-Glo assay. Flow cytometry was used to analyze the cell cycle (propodium iodide (PI) staining), apoptosis (annexin V/PI staining), mitochondrial membrane potential (MMP) (JC-1) and reactive oxygen species (ROS) (H 2 DCFH-DA). CCRF-CEM leukemia cells were used as model cells for mechanistic studies., Results: Compounds 1, 2 and 4 displayed IC 50 values below 20 µM towards CCRF-CEM and CEM/ADR5000 leukemia cells, and were further tested towards a panel of 7 carcinoma cells. The IC 50 values of the compounds against carcinoma cells varied from 16.90 µM (in resistant U87MG.ΔEGFR glioblastoma cells) to 48.67 µM (against HepG2 hepatocarcinoma cells) for 1, from 7.85 µM (in U87MG.ΔEGFR cells) to 14.44 µM (in resistant MDA-MB231/BCRP breast adenocarcinoma cells) for 2, from 4.96 µM (towards U87MG.ΔEGFRcells) to 7.76 µM (against MDA-MB231/BCRP cells) for 4, and from 0.07 µM (against MDA-MB231 cells) to 2.15 µM (against HepG2 cells) for doxorubicin. Compounds 2 and 4 induced apoptosis in CCRF-CEM cells mediated by MMP alteration and increased ROS production., Conclusion: The present report indicates that isoflavones and biflavonoids from Ormocarpum kirkii are cytotoxic compounds with the potential of being exploited in cancer chemotherapy. Compounds 2 and 4 deserve further studies to develop new anticancer drugs to fight sensitive and resistant cancer cell lines., (Copyright © 2019 Elsevier GmbH. All rights reserved.)