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HERDIN Record #: CAR-UCBCF-12101211371693 Submitted: 12 October 2012 Modified: 12 October 2012

Suppression of Growth of Some Medically Important Bacterial Pathogens (Escherichia Coli, Staphylococcus Aureus, Pseudomonas Aeruginosa, and Salmonella Typhimurium) with Plant Extracts of Selected Indigenous Semi-Temperate Medicinal Plants in the Philippines.

The suppression of growth of bacterial pathogens (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella typhimurium) employing the standard Modified Kirby-Bauer Disc Diffusion Assay was evaluated. In addition, the different plant extracts were also subjected to phytochemical screening to determine the presence of natural products (secondary metabolites), i.e., alkaloids, steroids, anthraquinones,flavonoids, saponins, tannins and polyphenols, and cyanogenic glycosides which may be responsible for the antibacterial property of the plants.

Extracts from the following plants were utilized: Persea americana (avocado), Chrysophyllum cainito (caimito), Anona muricata (guyabano), Artocarpus heterophyllus (langka), Carica papaya (papaya), and Sandoricum koetjape (santol). For the phytochemical screening, the presence of alkaloids, steroids, anthraquinones, flavovoids, saponins, tannins, and polyphenols in the leaf extracts were proven. In the test for antimicrobial activity, bacterial species treated with the plants extracts and the different antibacterial agents showed significant differences in terms of the zones of inhibition, while no change in the zones of inhibition of the microorganisms treated with methanol. The highest antimicrobial potential was observed in P. americana extract with the highest activity against S. aureus. However, C. cainito and A. teterophyllus extracts did not present any antimicrobial activity against S. typhimurium. The results of the present study suggest synergistic antibacterial activity between the antibiotics and plant extracts against the pathogenic bacteria. The results obtained with E. coli, P. aeruginosa, and S. typhimurium were particularly interesting since they were inhibited by most of the plant extracts.

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Publication Sub Type
Journal Article, Original
Tangkoyob: A Multidisciplinary Research Journal
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In this study, locally identified medicinal plants were analyzed for their phytochemical composition and their antibacterial property against common
clinical pathogens was also evaluated. This baseline information will provide the basis for developing potential drugs from these plants.