Isolation and Characterization of Anticancer, Radical Scavenging andAntimicrobial Natural Products Derived from Selected Medicinal Plants ofEthiopia”

Abstract

The increase in antibiotic resistance by microorganisms and the often lethal diseases caused byfree radicals is posing serious ramifications to the lives and health of humans. Thus, there is aneed to identify and process naturally occurring bioactive compounds which possess anticancer,antimicrobial and antioxidant activities. Based on the indigenous knowledge, literature reportsand survey of ethno-botanical use in traditional medicine; this study have been designed toinvestigate anticancer, antioxidant, antifungal and antibacterial properties of four indigenousmedicinal plants (Brucea antidysenterica, Erythrina abyssinica, Bersama abyssinica andEmbelia schimperi) and to further isolate and characterize bioactive compounds that relates tothe above biological properties. Sequential method of extraction with varying solvents polaritiesviz. n-hexane, dichloromethane: methanol (1:1) and methanol were used to extract the bioactivecompounds from the ground powdered plant materials. The isolation and purification ofbioactive compounds was done using chromatography techniques (CC and TLC). The root barksof Embelia schimperi, resulted in isolation and characterization of two flavans (1-2) whereasroots of Brucea antidysentrica, Bersama abyssinica and Erythrina abyssinia affordedcompounds indole alkaloids (3-6), steroids (7-9) and flavanoids (10-12), respectively. Details ofisolation, spectroscopic (UV-Vis, IR, NMR; 1D and 2D) characterization and antibacterialactivity of the isolated compounds is included in this report. The antibacterial activity the crudeextracts as well as isolated compounds were conducted using agar disk diffusion method.Molecular docking analysis was done for indole alkaloids (3-6) against DNA gyrase andaromatase enzymes in order to understand molecular mechanisms of antibacterial and anticanceractivity of these alkaloids.