Corn silk-derived bioactives as polyphenol oxidase inhibitors: Mechanisms and applications in food preservation

Enzymatic browning, primarily driven by polyphenol oxidase (PPO), poses a significant challenge in maintaining food quality and consumer acceptance across various sectors. This review critically examines available data on corn silk (Stigma maydis), an agro-industrial byproduct rich in antioxidant flavonoids (such as luteolin, apigenin, and formononetin), phenolic acids, and active carbohydrates. The gathered evidence indicates that corn silk compounds could effectively reduce PPO activity in both plant-derived and bacterial systems, suggesting they can mitigate browning through mechanisms that include direct enzyme inhibition and structural modulation of PPO's biophysical properties. In vitro studies further reveal that corn silk extracts enhance radical-scavenging activity and may offer antimicrobial benefits, thus contributing to improved food stability. Although promising applications range from fresh-cut produce treatments to incorporation into edible coatings and functional beverages, further research is required to optimize extraction methods, achieve formulation stability, and comprehensively assess sensory impacts and consumer acceptance. Overall, the reviewed research positions corn silk as a promising candidate for developing effective, safe, and environmentally friendly preservation strategies, while also highlighting the need for a multidisciplinary approach to fully integrate this natural resource into modern food systems.