Antimicrobial Effects of Three Plant-Derived Phenolic Compounds and Their Potential Role in Strawberry Preservation

Microbial spoilage of nutrient-rich strawberries leads to considerable food waste and economic losses. Plant-derived phenolic compounds, including resveratrol (RES), epigallocatechin gallate (EGCG), and tea polyphenols (TP), have gained attention for their multi-target antimicrobial efficacy and potential applications in fruit preservation. This study evaluated the individual and combined effects of these three compounds on strawberries infected with <i>Escherichia coli</i> (<i>E. coli</i>) and <i>Botrytis cinerea</i> (<i>B. cinerea</i>). The minimum inhibitory concentration (MIC) values for RES (analytical grade, ≥99% purity) and EGCG (analytical grade, ≥98% purity) against <i>E. coli</i> were 1.56 g/L and 25 g/L, with an additive effect against <i>E. coli</i> growth (FICI = 0.625). 5 g/L TP (analytical grade, ≥98% purity) completely inhibited the mycelial growth of <i>B. cinerea</i>. The in vivo application of RES and EGCG significantly reduced spoilage and improved texture, color, weight retention, and flavor quality in strawberries infected by <i>E. coli</i> individually or in combination. Similarly, the combined use of TP and chitosan saved the quality of strawberries infected by <i>B. cinerea</i> compared to single treatments. This study provided new effective and eco-friendly strategies for the preservation of strawberries.