# Antifungal Potential of Essential Oil Chemotypes of Eugenia uniflora Against Phytopathogens

## TL;DR

This study shows that essential oils from Eugenia uniflora can effectively inhibit plant-damaging fungi, offering a natural alternative to fungicides.

## Contribution

The study identifies specific chemotypes of E. uniflora with potent antifungal activity against phytopathogens.

## Key findings

- Essential oils from E. uniflora chemotypes inhibited Colletotrichum gloeosporioides and Pestalotia sp. with high efficacy.
- Chemical variability among chemotypes influences their antifungal potential.
- Inhibition rates were comparable to the fungicide tebuconazole with IC50 values between 0.01 and 0.09 mg mL−1.

## Abstract

This study investigated the chemical composition and antifungal activity of essential oils (EOs) from five chemotypes of Eugenia uniflora (E. uniflora) collected in the state of Rio de Janeiro, Brazil. GC–FID and GC–MS analyses revealed major compounds such as curzerene, selina‐1,3,7(11)‐trien‐8‐one, its epoxide, and spathulenol, indicating significant chemical variability. In vitro assays demonstrated that EOs from selected chemotypes exhibited strong inhibitory effects against the phytopathogens Colletotrichum gloeosporioides and Pestalotia sp., with inhibition rates comparable to the fungicide tebuconazole. IC50 values ranged from 0.01 to 0.09 mg mL−1. These findings reinforce the potential of E. uniflora as a natural source of bioactive compounds and support further exploration of its EOs for sustainable plant disease management. The observed intraspecific chemical diversity may influence biological effects and highlights the importance of chemotype selection in the development of botanical fungicides.

This study investigates the chemical profile and antifungal activity of Eugenia uniflora essential oils. The major constituents identified were selina‐1,3,7(11)‐trien‐8‐one and curzerene. The oils showed significant inhibitory effects against the phytopathogens Colletotrichum gloeosporioides and Pestalotia sp. These results emphasize the potential of E. uniflora metabolites as sustainable natural alternatives for fungal disease management in agriculture.