Optimization of culture conditions for enrichment of Campylobacter jejuni phages by host bacteria

Abstract:

[Background] The development of a bacteriophage-based product for the control of Campylobacter jejuni is a promising biocontrol strategy. However, bacteriophage isolation is a complicated challenge. [Objective] Response surface methodology was used to optimize the enrichment conditions of Campylobacter jejuni phages. [Methods] The effects of culture medium, culture temperature, shaking and ion additive on phage enrichment were analyzed through the single factor test. Based on response surface methodology (RSM), the recovery efficiency of phage was selected to evaluate enrichment culture conditions. [Results] The optimal culture conditions for enrichment were 37℃ and 0 r/min, recovery efficiency was 354.12%. The main procedures of bacteriophage isolation include sampling and sample preparation, incubation of sample filtrated with indicator strains, bacteriophage isolation and identification. Compared to the single spot method without enrichment, this enrichment method could increase the phage isolation rate by 269.23% from chicken fecal samples. [Conclusion] The optimized enrichment conditions of Campylobacter jejuni phages could improve the isolation efficiency of phages. It provides a new idea for phage isolation.

Key words:phage;Campylobacter jejuni;isolation;enrichment