In vitro effects of phytogenic feed additive on Piscirickettsia salmonis growth and biofilm formation
Natacha Santibáñez
Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
Interdisciplinary Center for Aquaculture Research (INCAR), Centro FONDAP, Concepción, Chile
Contribution: Methodology, Validation, Writing - original draft, Formal analysis
Search for more papers by this authorMatías Vega
Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
Interdisciplinary Center for Aquaculture Research (INCAR), Centro FONDAP, Concepción, Chile
Contribution: Methodology, Validation, Investigation
Search for more papers by this authorTatiana Pérez
Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
Interdisciplinary Center for Aquaculture Research (INCAR), Centro FONDAP, Concepción, Chile
Contribution: Investigation, Methodology, Validation
Search for more papers by this authorRicardo Enriquez
Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
Contribution: Conceptualization, Supervision
Search for more papers by this authorCarla Estefanía Escalona
Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
Interdisciplinary Center for Aquaculture Research (INCAR), Centro FONDAP, Concepción, Chile
Contribution: Investigation, Methodology, Validation
Search for more papers by this authorCristian Oliver
Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
Contribution: Writing - original draft, Writing - review & editing, Formal analysis, Validation, Conceptualization
Search for more papers by this authorCorresponding Author
Alex Romero
Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
Interdisciplinary Center for Aquaculture Research (INCAR), Centro FONDAP, Concepción, Chile
Correspondence
Alex Romero, Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Isla Teja s/n. Valdivia, Chile.
Email: [email protected]
Contribution: Conceptualization, Writing - original draft, Writing - review & editing, Validation, Methodology, Formal analysis
Search for more papers by this authorNatacha Santibáñez
Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
Interdisciplinary Center for Aquaculture Research (INCAR), Centro FONDAP, Concepción, Chile
Contribution: Methodology, Validation, Writing - original draft, Formal analysis
Search for more papers by this authorMatías Vega
Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
Interdisciplinary Center for Aquaculture Research (INCAR), Centro FONDAP, Concepción, Chile
Contribution: Methodology, Validation, Investigation
Search for more papers by this authorTatiana Pérez
Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
Interdisciplinary Center for Aquaculture Research (INCAR), Centro FONDAP, Concepción, Chile
Contribution: Investigation, Methodology, Validation
Search for more papers by this authorRicardo Enriquez
Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
Contribution: Conceptualization, Supervision
Search for more papers by this authorCarla Estefanía Escalona
Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
Interdisciplinary Center for Aquaculture Research (INCAR), Centro FONDAP, Concepción, Chile
Contribution: Investigation, Methodology, Validation
Search for more papers by this authorCristian Oliver
Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
Contribution: Writing - original draft, Writing - review & editing, Formal analysis, Validation, Conceptualization
Search for more papers by this authorCorresponding Author
Alex Romero
Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
Interdisciplinary Center for Aquaculture Research (INCAR), Centro FONDAP, Concepción, Chile
Correspondence
Alex Romero, Laboratorio de Inmunología y Estrés de Organismos Acuáticos, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Isla Teja s/n. Valdivia, Chile.
Email: [email protected]
Contribution: Conceptualization, Writing - original draft, Writing - review & editing, Validation, Methodology, Formal analysis
Search for more papers by this authorAbstract
Piscirickettsiosis is the main cause of mortality in salmonids of commercial importance in Chile, which is caused by Piscirickettsia salmonis, a Gram-negative, γ-proteobacteria that can produce biofilm as one of its virulence factors. The Chilean salmon industry uses large amounts of antibiotics to control piscirickettsiosis outbreaks, which has raised concern about its environmental impact and the potential to induce antibiotic resistance. Thus, the use of phytogenic feed additives (PFA) with antibacterial activity emerges as an interesting alternative to antimicrobials. Our study describes the antimicrobial action of an Andrographis paniculate-extracted PFA on P. salmonis planktonic growth and biofilm formation. We observed complete inhibition of planktonic and biofilm growth with 500 and 400 μg/mL of PFA for P. salmonis LF-89 and EM-90-like strains, respectively. Furthermore, 500 μg/mL of PFA was bactericidal for both evaluated bacterial strains. Sub-inhibitory doses of PFA increase the transcript levels of stress (groEL), biofilm (pslD), and efflux pump (acrB) genes for both P. salmonis strains in planktonic and sessile conditions. In conclusion, our results demonstrate the antibacterial effect of PFA against P. salmonis in vitro, highlighting the potential of PFA as an alternative to control Piscirickettsiosis.
CONFLICT OF INTEREST STATEMENT
The authors declare no conflict of interest.
Open Research
DATA AVAILABILITY STATEMENT
The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.
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