Abstract

In this study, the antibacterial activities of medicinal plant extracts [of Rehumpalmatum (R), Cassia angustifolia (C), Glycyrrhiza glabra (G), Chichorium intybus(Ch), and Matricaria chamomilla (M)], on antibiotic- resistant isolates (Staphylococcus aureus and Alcaligenes xylosoxidans) collected from clinical samples, pharmaceutical products, and different hospital water drains was detected (single, combined extract). This investigation shows that the extracts of G. glabra, R. palmatum and C. angustifolia and their combination with the selected antibiotic, variously inhibited the growth of the bacterial isolates. The methanol extraction ingredients recorded the maximum Inhibition Zone Diameter (mm IZD); 18.8/R, 12.6/C and 12.8/G plants. Prominent synergism occurred between plants extract mixture and Gentamycin, Ceftasidine, Tobramycin, Cefoperazone and Spictinomycin (GD) antibiotics. Rehum plant extract was the most potent antibacterial agent against S. aureus and A. xylosoxidans, especially when extracted with methanol solvent.

Key words: Synergism, antagonism, Glycyrrhiza glabra, Rehum palmatum, Cassia angustifolia, antibiotic-resistant bacteria, Staphylococcus aureus, Alcaligenesxylosoxidans, hospitals drain, clinical samples, volatile oils, total flavonoids.

Abbreviation

Abbreviation: R, Rehum palmatum; C, Cassia angustifolia; G, Glycyrrhiza glabra; C, S1, S2, S3 and S4, Staphylococcus aureus isolates; A, Alcaligenes xylosoxidansisolate.