Selective Antimicrobial and Cytotoxic Effects of Hop Compounds to Combat Poultry Antimicrobial Resistance.

The rising global population has led to an increased demand for poultry meat, necessitating the development of sustainable and safe alternatives to antibiotic growth promoters, which have been banned or restricted due to concerns about antibiotic resistance. Phytogenic feed additives (PFAs), particularly hop-derived compounds, have shown promise as natural antimicrobial agents. This study investigates the antibacterial and cytotoxic properties of five major hop-derived compounds -isoxanthohumol, xanthohumol, humulone, lupulone, and isohumulone -to assess their potential as PFAs in poultry farming. Using broth dilution and metabolic activity assays, minimum inhibitory concentrations (MIC50) and cytotoxic concentrations (IC50) were determined against Micrococcus luteus, Bacillus subtilis, and a chicken fibroblast cell line (UMNSAH/DF-1). Among the compounds tested, xanthohumol demonstrated the most favorable selective index against M. luteus (5.5 ± 0.36), while for B. subtilis, lupulone had an even higher index (15 ± 0.77). These findings highlight the novel potential of specific hop-derived compounds as selective and safe PFAs, contributing valuable insights into natural alternatives to conventional antibiotic growth promoters.