Lycopene Regulates Gut Fungi through Bacterial Vitamin B6-Mediated <i>Trichocladium</i> Suppression

Fungal dysbiosis is increasingly recognized as a critical factor in gut-related diseases, yet natural antifungal agents remain scarce. Lycopene is known to influence gut health, but its effects on fungi also remain unclear. This study investigated the impact of lycopene on the gut microbiota, particularly gut fungi. <i>In vivo</i>, lycopene significantly promoted the growth of beneficial species such as <i>Lactobacillus johnsonii</i> and altered microbial vitamin B6 metabolism. Metabolomics analysis further confirmed that lycopene enhanced vitamin B6 metabolism. <i>In vitro</i> fermentation using human gut microbiota confirmed similar effects. Then, inhibition of bacteria and fungi, along with the antagonism of vitamin B6, confirmed significant changes in the abundance of <i>L. johnsonii</i> and <i>Trichocladium</i>, mediated through vitamin B6 metabolism. Further monoculture experiments with <i>Trichocladium</i> demonstrated that vitamin B6, rather than lycopene itself, significantly reduced the abundance of <i>Trichocladium</i>. Structural equation modeling revealed lycopene's potential in modulating fungi within the gut ecosystem.