An Examination of the Antibacterial Effect of the Ink of Persian Gulf’s Sea Hare Aplysia dactylomela on Some Aquatic Pathogens

,Different variations of Aplysia have been appealing options in medical and pharmaceutical researches for years. Persian Gulf’s sea hare—Aplysia dactylomela—is a species native to Persian Gulf and can be evaluated in various areas. In this research, carried out in 2019 in Persian Gulf University’s Research Centre, the antibacterial potential of the ink of this species has been measured against three pathogenic bacteria in aquatics, namely Yersinia rukeri, Streptococcus iniae, and Vibrio Harvey. The purple ink was extracted out of ten sea hares of Aplysia dactylomela species, the ink has then been applied in raw form against the above-mentioned bacteria in an anti-bacterial test. The measurement of the antibacterial properties has been done through disc diffusion method and the minimum inhibitory concentration(MIC) and the minimum bacterial concentration(MBC) have been determined with serial dilution. Gentamicin and Tetracycline antimicrobial discs have been used as positive evidence. The average inhibitory zone for V.harvey turned out to be 19/24 millimetres, the MIC  was 200 milligrams in millilitre and the MBC was 400 milligrams  in millilitre. The inhibitory zone for S.iniae turned out to be 21/72 millimetres; the MIC was 50 milligrams in millilitre and the MBC was 200 milligrams in millilitre. Accordingly, the inhibitory zone for Y.rukeri turned out to be 22/36 millimetres; the MIC was 50 milligrams in millilitre and the MBC was 100 milligrams in millilitre.The ink of Persian gulf’s sea hare  in this research revealed antibacterial effect in reaction to all the three bacteria.