الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
 |  | from | 108 |  |  |
| | | from | 108 | | |
Abstract
Nine Egyptian medicinal plants including; Chenopodium album, C. murale, C. ambrosioides, Lantana camara, Conyza dioscoridis, C. linifolia, Phlomis floccosa, Withania somnifera and Tribulus terrestris were screened for their antibacterial, antifungal and antioxidant activities. The active constituents were extracted using each of chloroform, methanol and hot water, in addition to the preparation of the two essential oils from C. ambrosioides and L. camara. Five microbial indicators were used in this study including; Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella pneumonia and Candida albicans. The chloroformic extracts of most plants showed higher antimicrobial activity than the methanolic extracts, while the water extracts of most plants were inactive. The essential oil of C. ambrosioides showed the best antibacterial results against S. aureus (AU=26.13±O.98), E. coli (AU=20.77±O.89), K. pneumonia (AU= 17 .36±O.OO) and E. faecalis (AU=6.8l±O.50), which were even higher than that exhibited by Cefradine as a reference antibiotic (AU=7.72±O.54, 3.57±0.37, 8.35±0.56 and 6.53±O.50, respectively). The chloroformic extract of C. linifolia exhibited the best antifungal activity among the investigated plant extracts against C. albicans (AU=10.39±O.62). Concerning the antioxidant activity, the methanolic extracts showed higher activity than that exhibited by the chloroformic extracts. The methanolic extract of 1. camara exhibited the best antioxidant activity (95.81±O.31 % at 600f.lg/ml), followed by the methanolic extracts of C. dioscoridis (94.33±O.20% at 800f.lg/ml), P. floccosa (95.63±O.1 % at 1000f.lg/ml) and W. somnifera (89.58±2.94% at lOOOf.lg/ml), while the remaining plant extracts showed results that ranged from moderate to weak antioxidant activities.