Antimicrobial activity of leaf extract of Ocimum sanctum on various clinical isolates

Abstract

Abstract:Medicinal properties are present in different parts of Ocimum sps. like leaves flowers, root, stem etc. and have been used by traditional medical practitioners. The aim of this study was to determine the antimicrobial activity of cold and hot water extract of leaves of Ocimum sanctum against clinical bacterial isolates by disc diffusion method. Cold and hot water extract of leaf of Ocimum sanctum were prepared at 250µg/ml, 500µg/ml, 1000µg/ml concentrations, impregnated into discs of 6mm diameter and tested on S.aureus, B.subtilis, E.coli, Proteus mirabilis, Shigella dysentriae, Salmonella typhimurium . There was no significant difference between the zone of inhibition of the test organisms to cold and hot water extracts. S. aureus and S. typhimurium had the zone size of 1.2 cm, 1.1 cm and 1.0 cm zone of inhibition for B. subtilis and Shigella dysentriae respectively. The inhibition was the greatest at concentration of 1000 µg/ml for both cold and hot water extracts against all test organisms. The antimicrobial activity was the maximum for E. coli i.e. 1.4 cm in both cold and hot water extracts. The antimicrobial susceptibility pattern of leaf extract of Ocimum sanctum was found to be more or less active against all tested pathogenic strains for both cold and hot water extracts; it may be due to the presence of tannins, essential oils, flavonoids, alkaloids and eugenol present in varying proportions. The plant contains important bio-active compounds and hence has found use as essential plant species in traditional medicine for treatment of various diseases.

Potential of Ocimum sanctum to Inhibit the Growth of Pseudomonas aeruginosa, a Disease-causing micro-organism

“…coli, Aggregatibacter actinomycetemcomitans, indicating that this plant contains a lot of active phytochemical components showing antimicrobial activities. 2,[23][24] The previous study also noted the antimicrobial activity of O. sanctum leaf extract against P. aeruginosa, 4 which supports the findings of the present study. However, there are only few studies available and therefore, the present study underlined the necessity for further study to explore the use of the available antimicrobial agent in O. sanctum against P. aeruginosa.…”

“…The antimicrobial action of phytochemicals is mediated by a variety of mechanisms. Alkaloids serve as a DNA intercalator and decrease DNA synthesis by inhibiting topoisomerase, 23 tannins' antimicrobial effect includes inhibition of oxidative phosphorylation, deprivation of substrates needed for microbial development and inhibition of extracellular enzymes. 25 Use of medicinal plants reveals various other benefits including the fact that they are readily available, inexpensive and safe to use.…”