摘要Objective: To evaluate the antimicrobial capacity of fucoidan from the brown seaweed Turbinaria ornata against the marine ornamental fish bacterial pathogens. Methods: Fucoidan was isolated by the ethanol extraction method and the were identified by Fourier Transform Infrared Spectroscopy analysis. Subseq fuuenncttliyo,n satlr ugcrtouurpasl pcherafroarcmteerdi zbayt itohne wagaasr dpolantee bdyif f1uHsi oNnM mR eatnhoadly asinsd. MIni nviimtruom a nIntihbiabcittoerryia Cl oanccteivnittrya toiof nf.ucoidan was Results: The characteristic C-O-S bending vibration of sulfate substituent the axial C-4 was observed at 839 cm-1. Characterisitic signal of the fucoidan was detected in a different ppm of 1H NMR analysis. The maximum antibacterial activity (16.23±0.11) mm was obtained for Vibrio parahaemolyticus and the minimum activity (5.1±0.24) mm was recorded for Yersinia enterocolitica. Trehsep eMctiinviem puamth oIgnehnibs.itory Concentration value was recorded between 2.5 to 10 mg/mL to the Conclusions: The present study proved that fucoidan possessed the significant antibacterial ainc taivni tayq augaaciunlsttu trhee s ytesstetemd tfois hco bnatcrotel rtihael pbaatchtoegrieanl sd. iIste caosuelsd. Hbeo wfuervtehre,r t huese pdr easse an tn asttuudrayl saungtgibeisotteidc ftuhacto itdhaen f.urther