An antibacterial activity of selected brown, green and red seaweeds from Manapad, Thoothukudi, Tamil Nadu, India

Abstract

Antibacterial activity of three seaweeds, namely Padina tetrastromatica, Caulerpa sertularioides and Kappaphycus alvarezii were screened against six bacterial pathogens (Bacillus subtilis, Staphylococcus aureus, Lactobacillus acidophilus, Escherichia coli, Pseudomonas aeruginosa and Proteus mirabilis). Extracts of selected seaweeds were prepared in Acetone, Chloroform, Ethanol, Ethyl acetate and Methanol. The antibacterial activity was carried out by the agar well diffusion method. Ethanol extracts showed effective inhibition against all the bacterial pathogens used. But the highest activity (18mm) was observed by the extract of Caulerpa sertularioides against Proteus mirabilis by using Ethyl acetate as a solvent. The lowest activity was reported for the ethyl acetate extracted Kappaphycus alvarezii (3mm) against bacterium E. coli. The entire six pathogens were resistant to the chloroform extracts of Caulerpa sertularioides and Kappaphycus alvarezii.