Evaluación de la producción y conservación de bacteriófagos líticos de Salmonella enterica con medios de cultivo económicos y sustancias crioprotectoras alternativas

Abstract

Bacteriophages represent an alternative for the elimination of potentially pathogenic microorganisms. However, their use involves numerous stages that include selection, generation of high phage titers, preservation, characterization, and assessments of their effectiveness. These processes require a significant financial investment in culture media and preservation methods, which could limit their applicability in scaling up.

Therefore, in this study, cost-effective culture media were generated and alternative cryoprotective substances were used to improve the efficiency in obtaining and preserving high phage titers, thus facilitating their future industrial use. The formulation of culture media was carried out, using the avian-origin strain S. enterica serovar Infantis S11V23 as the host, and the bacteriophage Berlinvirus sp. F6_melonhead. Initially, the behavior of the bacteria and the phage against each formulation was analyzed. Finally, alternative cryoprotective substances were employed to evaluate the preservation of the titer over a period of 56 days at temperatures of 4, 20, and -70 degrees Celsius. The feasibility of obtaining bacterial and phage biomass using cost-effective culture media based on malt extract and brewer's yeast extract was proven, being effective for generating high phage titers. Furthermore, the stability of the bacteriophages at -70 Degrees Celsius was achieved using de-lactosed milk as a cryoprotective substance. The results highlight the possibility of scaling up bacteriophage production with limited resources and greater efficiency in generating bioproducts for the control of S. enterica useful for the poultry industry.