Antibacterial activity of Bacillus licheniformis isolated from marine sediments and its effect in treating Aeromonas hydrophila infection in freshwater prawn, Macrobrachium rosenbergii

• Published in: Aquaculture international 2023-12, Vol.31 (6), p.3071-3093
• Main Authors: Mondal, Haimanti, Chandrasekaran, Natarajan, Mukherjee, Amitava, Thomas, John
• Format: Article
• Language: English
• Subjects: Aeromonas hydrophila; Antibiotics; Aquaculture; Aquatic habitats; Bacillus licheniformis; Bacteria; Bioactive compounds; Biomedical and Life Sciences; Disease resistance; Drugs; Fourier transforms; Freshwater; Freshwater & Marine Ecology; Freshwater crustaceans; Histopathology; Infections; Infectious diseases; Inland water environment; Life Sciences; Macrobrachium rosenbergii; Marine crustaceans; Marine sediments; Microbiological strains; Microorganisms; Pathogens; Pesticides; Phenols; Sediments; Shellfish; Survival; Zoology
• ISSN: 0967-6120; 1573-143X
• DOI: 10.1007/s10499-023-01121-8

Actinomycetes from marine habitats are relatively unexplored. They are reported as potential sources of novel bacterial species. In this current study, 16 strains of bacteria were isolated using Actinomycetes Isolation Agar medium. Two strains showed antibacterial activity against the shrimp pathogens, Aeromonas hydrophila and Vibrio parahaemolyticus. Among them, only 1 strain was found to have potent antibacterial properties. This strain was designated as Bacillus licheniformis VIT02. The crude bioactive compounds obtained from Bacillus licheniformis were extracted and identified using FTIR and GC–MS analyses. The data revealed that the phenolic bioactive compound, phenol,2,4-bis(1,1-dimethylethyl), and ester compound, propanoic acid, 2-Hydroxy-, Ethyl Ester, (S) have antimicrobial properties, and hence, can be used as potent antimicrobial drugs after performing further studies. The in vivo pathogenicity in Macrobrachium rosenbergii was investigated against A. hydrophila for 120 h. After 120 h of exposure, 34% of mortality was observed at the highest concentration of 10 6 A. hydrophila . The in vivo treatment using the bioactive compound from the isolated strain B. licheniformis was performed against A. hydrophila in M. rosenbergii . The shrimp challenged with A. hydrophila when treated with 25 µL of bioactive compounds extracted from B. licheniformis showed 90% of survival up to 15 days of exposure. A survey of literature revealed that this could be the first study reporting the treatment of A. hydrophila infection in M. rosenbergii using the bioactive compounds from marine Actinomycete , Bacillus licheniformis VIT02. The histopathological analysis revealed that there was difference between the infected and the treated groups when compared with the control. The results indicated that the crude bioactive compound revealed potent disease resistance capacity against A. hydrophila in M. rosenbergii .