Elucidation of Antibacterial and Antioxidant Activities of Sesuvium portulacastrum leaf extracts

Abstract

Mangroves have evolved several physiological and morphological changes over the course of time to withstand the harsh environmental conditions of the coastal regions. They provide a safe niche for a uniquely diverse flora and fauna. The evolutionary adaptation to harsh climate has provided mangroves with novel secondary metabolites and bioactive compounds which have found to be beneficial for human consumption. These bioactive compounds found in the Mangroves can also curb the growth of bacteria. Sesuvium portulacastrum, is a Mangrove, commonly called as the “sea purslane” which has been found to contain Antioxidant and Antibacterial properties. In the present study, crude extracts of S. portulacastrum have been made from Acetone, Diethyl ether, Petroleum ether and water. Acetone crude extract was found to exhibit phytochemicals such as alkaloids, saponins, flavonoids, proteins and Anthraquinones. Diethyl ether crude extract has shown the presence of Tannins, Saponins, Phenols and Proteins. Aqueous extract of S. portulacastrum has shown the presence of most of the phytochemicals such as alkaloids, tannins, saponins, glycosides, steroids, phenols, anthraquinones and reducing sugars, on the other hand, petroleum ether crude extract had shown the presence of only two phytochemicals viz., glycosides and steroids. Based on the phytochemical screening, the Antibacterial test was assayed through agar well diffusion method using the aqueous extract of S. portulacastrum against Bacillus thuringiensis, Pseudomonas aeruginosa, Staphylococcus aureus and Klebsiella pneumoniae. It can be observed from the experiment that the maximum Zone of Inhibition was noted against Klebsiella pneumoniae (1.2±0.4 mm) and the minimum Zone of Inhibition was observed against Bacillus thuringiensis (0.5±0.02 mm). Similarly assays like DPPH and FRAP of the aqueous leaf extract have shown that S. portulacastrum has significant Antioxidant properties as well. The IC₅₀ values of DPPH were noted to be 289.92 µl/ml and the FRAP assay has shown an increase in the reduction power with a range between 9.33 ± 0.11 µg/ml at 15.62 µg/ml concentration and 44.16 ±0.21 µg/ml at 250 µg/ml concentration.