Paper Title
Isolation of Antibiotic Compounds from Seaweeds, Collected from Kootapuly Coastal Waters, Tamil Nadu, India and Tested Against Selected Pathogens

The objective of the present study was focused on to investigate the bioactive potential of seaweeds against fish pathogens. The extracts of seaweeds,Sargassum tennerimum and Halimeda tuna were obtained from three different solvents, such as Methanol, Acetone and Petroleum ether. Petroleum ether and acetone crude extracts of both seaweeds have shown promising activity against allfish pathogens. Petroleum ether extract of Sargassum tennerimumshowed wide spectrum of inhibitory activity and the highestactivity was observedagainst Pseudomonas aeroginosa (9mm) and followed byAeromonashyddophila (8 mm) and Vibrio sp. (7 mm). A highest-level activity was exhibited by acetone extract of Halimeda tuna with maximum zone of range of 6 mm and 5 mm against Flavobacterium sp. and Pseudomonas aeroginosarespectively. Observed results revealed that both seaweeds possess biomedically active compounds which may pave the way for the discovery of novel chemical compounds, which can be used in the field of aquaculture to treat fish diseases. Hence, seaweeds could be utilized as a potential source of natural products from marine environment. Further studies have to be carried out to be identified and purified the individual compounds by subsequent techniques, TLC, HPTLC, HPLC, GC, NMR, GCMS, IR etc. Keywords - Seaweeds, bioactive compounds, Fish pathogens, Marine drugs.