Author: Ali.A. Eltayeib and Nahla Agab

Abstract: The aim of this study was to identify chemical composition, antimicrobial and antioxidant activity of extracts of stems and roots (mixture 1:1) and seeds from mahareb plant. The seeds, stems and roots were collected from alshareef allged (north kordofan state), during March (2018), dried under shade, grinded and then extracted by maceration method using 99% methanol, petroleum ether and distilled water. Photochemical screening revealed the presence of flavonoids, terpenoids, saponins and tannins with high concentration except alkaloids with low concentration in extracts. Crude extracts and tetracycline with different concentrations (40, 60, 70 and 90 mg/ml) were applied against four bacterial strains (two Gram positive: Sterbeto cocai (S.c), Staphylococcus aureus (ATCC 25923); and two Gram negative: Escherichia Coli (E.c)(ATCC 25922), Pseudomonas aerruginosa (P.s.a) (ATCC 27853) and with 100 mg/ml against one type of fungus (candida albicans (ATCC 7596) using agar plate well-diffusion method. According to this method the inhibition zone less than 14 resistance, 14 to 18 medium and larger than 18 mm sensitive. Methanol seeds extract at 90mg/ml showed activity against P.s.a (22mm) and E.c (17mm). Methanol roots and stems extracts at 70mg/ml showed activity against P.s.a (17mm). Tetracycline at 90 and 60mg/ml showed activity against (E.c 20mm, S.c 16mm) and (E.c 16mm) respectively. The extracts showed no activity against candida albicans. The free radical scavenging activity of the crude extracts was evaluated using 2,2 -Di (4-tert-octylphenyl)-1-picryl hydrazyl stable free radical (DPPH). The extracts showed a DPPH scavenging activity of 16±0.08, 85±0.00, 46±0.08 (for seeds extracted by water, methanol and petroleum ether respectively) and 10±0.07, 56±0.08, 4±0.07 (for stems and roots mixture extracted by water, methanol and petroleum ether respectively). The standard propyl gallate showed 95±0.02 scavenging activity. Analysis of the crude extracts by GC-MS showed 56, 52, 5, 9, 54, 38 compounds for seeds, stems, and roots extracted by methanol, water, and petroleum ether respectively.  

Keywords: Symbopogon schoenanthus, stems, roots, chemical compounds.