Antimicrobial and antioxidant activity of crude extracts of two medicinal plants **Pistacia integerrima** and **Debregeasia salicifolia**
Faculty of Pharmaceutical, Biomedical and Veterinary Sciences. Pharmacy
International journal of pharmaceutical sciences : review and research
, p. 13-17
University of Antwerp
The methanolic extracts of different parts of the two medicinal plants Pistacia integerrima Stewart Ex Brandis (Anacardiaceae) and Debregeasia salicifolia Rendle (Urticaceae) were studied for in vitro antimicrobial and antioxidant activity. The antimicrobial study was carried against various species of bacteria. Gram positive bacteria consisted of Staphylococcus aureus, Bacillus subtilis and Gram negative of Proteus mirabilis, Salmonella typhi, Escherichia coli and itrobacter. The antioxidant study was performed through DPPH (1, 1-diphenyl-2-picrylhydrazyl) radical scavenging activity using ascorbic acid as standard. Roots and bark showed high zones of inhibition at low concentrations while the leaves showed activity at high dose concentrations of the crude extracts. Debregeasia salicifolia was effective against Bacillus subtilis with zone of inhibition 17.50 mm and at a dose of 150 μg. The highest zone of inhibition was shown by Pistacia integerrima leaves up to 28.00 mm against Citrobacter at the highest test dose of the extract, while the bark of Pistacia integerrima was also very effective showing a zone of inhibition of 21.80 mm against Staphylococcus aureus even at a very small dose of 150 μg. The crude extracts were compared against two standard drugs neomycin and doxycyclin. Pistacia integerrima bark and leaves were highly effective as free radical scavengers and the results were comparable to the standard ascorbic acid, while the leaves and roots of Debregeasia salicifolia also showed a very potent anti-oxidant activity but still less effective then Pistacia integerrima.