Electronic Theses and Dissertation

Penggunaan antibiotik dalam budidaya masih banyak dilakukan untuk mengendalikan infeksi bakteri, namun pemakaian yang tidak tepat dapat memicu resistensi antimikroba dan menimbulkan risiko keamanan lingkungan. probiotik indigenous menjadi salah satu alternatif untuk mendukung kesehatan ikan dan mengurangi ketergantungan terhadap antibiotik. penelitian ini bertujuan mengevaluasi profil resistensi antibiotik dan aktivitas hemolitik delapan isolat bakteri asam laktat (bal) dari saluran pencernaan ikan naleh (barbonymus sp.) sebagai tahapan seleksi kandidat probiotik. uji resistensi antibiotik dilakukan dengan metode kirby–bauer, sedangkan uji hemolitik menggunakan media blood agar. hasil menunjukkan bahwa terhadap ampisilin, 50% isolat bersifat resisten, 37,50% intermediet, dan 12,50% sensitif. sebanyak 50% isolat bal menunjukkan resistensi terhadap tetrasiklin, sedangkan 50% lainnya bersifat sensitif. seluruh isolat bal juga resisten terhadap gentamisin, kanamisin, dan streptomisin. isolat nb12 menunjukkan profil resistensi antibiotik yang potensial, sedangkan nj27 merupakan satu-satunya isolat γ-hemolitik. hasil ini menunjukkan bahwa evaluasi resistensi antibiotik dan hemolisis penting dilakukan untuk memastikan keamanan bal indigenous ikan naleh sebagai kandidat probiotik dalam budidaya. kata kunci: ikan naleh (barbonymus sp.), uji resistensi antibiotik, aktivitas hemolitik, bakteri asam laktat (bal), probiotik

The use of antibiotics in aquaculture is still commonly applied to control bacterial infections however, inappropriate use may promote antimicrobial resistance and pose environmental safety risks. Indigenous probiotics represent an alternative approach to support fish health and reduce dependence on antibiotics. This study aimed to evaluate the antibiotic resistance profile and hemolytic activity of eight lactic acid bacteria (LAB) isolates from the digestive tract of naleh fish (Barbonymus sp.) as an initial selection step for probiotic candidates. Antibiotic resistance testing was performed using the Kirby–Bauer method, while hemolytic activity was assessed on Blood Agar medium. The results showed that, against ampicillin, 50% of the isolates were resistant, 37.50% were intermediate, and 12.50% were sensitive. A total of 50% of the LAB isolates showed resistance to tetracycline, while the remaining 50% were sensitive. All LAB isolates were also resistant to gentamicin, kanamycin, and streptomycin. Isolates NB12 showed potential antibiotic resistance profiles, while NJ27 was the only γ-hemolytic isolate. These findings indicate that antibiotic resistance and hemolysis evaluations are important to ensure the safety of indigenous LAB from naleh fish as probiotic candidates for aquaculture. Keywords: Naleh Fish (Barbonymus sp.), Antibiotic Resistance, Hemolytic Activity, Lactic Acid Bacteria (LAB), Probiotic