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

## TL;DR

This study explores hop compounds as natural alternatives to antibiotics in poultry farming, finding some are effective against bacteria without harming chicken cells.

## Contribution

The study identifies xanthohumol and lupulone as promising hop-derived compounds with high selectivity against specific bacteria.

## Key findings

- Xanthohumol showed a selectivity index of 5.5 ± 0.36 against Micrococcus luteus.
- Lupulone had a higher selectivity index of 15 ± 0.77 against Bacillus subtilis.
- Hop compounds are promising natural antimicrobial agents for poultry.

## Abstract

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.

Phytogenic feed additives (PFAs) like hop (Humulus lupulus) offer a sustainable alternative to antibiotics in the expanding global poultry market. This study tested five hop‐derived compounds for antibacterial activity against Micrococcus luteus and Bacillus subtilis, and for their cytotoxicity in chicken cells. Xanthohumol showed the highest selectivity index (5.5 ± 0.36) for M. luteus, while lupulone had an even higher index (15 ± 0.77) for B. subtilis. Hop compounds are therefore promising candidates for sustainable PFAs in poultry farming.