Impact of High-Pressure Processing on Phenolic Compound Accumulation and Expression of Key Biosynthetic Genes in Harvested Strawberries

Abstract

Phytochemical accumulation plays a vital role in plant defense. This study examines the effect of high-pressure (HP) treatment on phenolic biosynthesis and gene expression in harvested strawberries, evaluating HP as a potential enhancer of phenolic biosynthesis through environmental stress responses. Strawberries were subjected to HP treatment at pressures ranging from 10 to 40 MPa in two or three cycles. This treatment led to significant increases in total phenolic content, up to 1.59 times higher than untreated controls. Gene expression analysis showed upregulation of key biosynthetic genes—phenylalanine ammonia-lyase, chalcone synthase, and UDP-glucose flavonoid 3-O-glucosyl transferase—with peak expression observed after three cycles of treatment at 40 MPa. HP treatment effectively enhances phenolic compound synthesis by activating biosynthetic gene expression pathways. This method presents a practical, non-genetic strategy for improving the nutritional profiles of fruits.