Fisetin is a flavonol phytochemical found in strawberries, apples, persimmons, onions, grapes, cucumbers, and additional fruits and vegetables. It contributes to the antioxidant polyphenol profile of many plant foods.
Fisetin functions mainly as a polyphenolic antioxidant involved in oxidative stress modulation, inflammatory pathway interactions, mitochondrial responses, and cellular redox regulation. Research has explored its effects on reactive oxygen species pathways, antioxidant enzyme systems, inflammatory mediators, and stress-responsive signaling systems.
Within plants, fisetin contributes to defense against environmental oxidative stress and ultraviolet exposure.
Plants synthesize fisetin through flavonoid biosynthesis pathways derived from phenylalanine metabolism. Environmental stress, sunlight exposure, plant maturity, and cultivar influence concentrations.
Strawberries are among the best recognized dietary sources. Processing and storage conditions can alter flavonol stability and availability.
After ingestion, fisetin undergoes absorption, conjugation, microbial metabolism, and circulation through detoxification pathways.
Fisetin activity is regulated by food matrix interactions, intestinal absorption, microbiome metabolism, hepatic conjugation, and oxidative environment. Flavonoid metabolism strongly influences tissue exposure.
Research suggests fisetin may interact with oxidative stress pathways, inflammatory mediators, mitochondrial systems, and cellular stress responses. Biological effects depend on concentration, metabolism, and tissue localization.
Consumption from fruits and vegetables provides fisetin together with fiber, vitamin C, minerals, and additional flavonoids that collectively contribute to antioxidant and vascular signaling diversity.
| Inhibitor / Factor | Effect on Activity / Absorption |
|---|---|
| Phase II conjugation; low aqueous solubility; matrix effects. |
