Inhibition Zone Test of Chaetomorpha sp. Extract Against Aeromonas hydrophilla and Vibrio sp. Bacteria

Chaetomorpha sp. is a green algae that has anti-bacterial compounds and at certain times found very much. The purpose of this study was to see the inhibition zone produced from ethanol extract against A. hydrophilla Vibrio This research done in March 2022. Extraction sp., antibacterial effectiveness testing Biotechnology Laboratory, Faculty Fisheries Marine, Riau University. method used descriptive method. Sensitivity test performed using Kirby Bauer disc To reduce error rate, it repeated three times. doses macroalgae were, 100% (10,000 ppm), 90% (9,000 80% (8,000 70% (7000 60% (6000 50% (5000 40 % (4000 30% (3000 20% (2000 10% (1000 ppm) control (Oxytetracycline). Based on observations, use result able inhibit growth bacteria highest dose (10000 an range 13.5 -14.5 mm which classified as strong category, lowest 5000 ppm moderate category.