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 Escherichia coli (E. coli) and Botrytis cinerea (B. cinerea). The minimum inhibitory concentration (MIC) values for RES (analytical grade, ≥99% purity) and EGCG (analytical grade, ≥98% purity) against E. coli were 1.56 g/L and 25 g/L, with an additive effect against E. coli growth (FICI = 0.625). 5 g/L TP (analytical grade, ≥98% purity) completely inhibited the mycelial growth of B. cinerea. The in vivo application of RES and EGCG significantly reduced spoilage and improved texture, color, weight retention, and flavor quality in strawberries infected by E. coli individually or in combination. Similarly, the combined use of TP and chitosan saved the quality of strawberries infected by B. cinerea compared to single treatments. This study provided new effective and eco-friendly strategies for the preservation of strawberries.