Isolation and Selection of Actinobacteria Against Pathogenic Bacteria From Shrimp Pond Water on Duyen Hai District, Tra Vinh Province, Vietnam

Abstract— In the shrimp-farming process at Vietnam has used antibiotic mostly, this leads status of antibiotic resistant bacteria and product do not qualified to the market. Bacteria, especially actinobacteria, had resistant ability to human pathogenic bacteria in water and they have an important role in sustainable aquaculture. This study aimed to isolate and select good actinobacterial strains against pathogenic bacteria, from 8 samples of shrimp-pond water at 3 sites Ngu Lac, Phuoc Tri and Long Toan of Duyen Hai district, Tra Vinh province on Gause-1 agar medium. Fifty-three actinobacterial isolates were isolated in which 23 isolates resistant to at least one of pathogenic bacteria by well-diffusion method. Among them, 15 isolates were identified as resistant to Bacillus cereus, 12 to Staphylococcus aureus, 11 to Escherichia coli and 18 to Vibrio parahaemolyticus. There were 7 isolates had good resistance to select for PCR technique and sequencing and the result were determined 7 these strains: NL1-1.9, NL1-18a, NL2-2.1b1, NL2-2.2, PT1-1.7a, PT2-2.8a, LT1-1.3 belonged to three genere: Streptomyces, Nocardioides, and Glutamicibacter.