Hesperidin (CAS: 520-26-3) is a natural flavonoid compound extracted from the dried immature fruits of Citrus aurantium L. and Citrus sinensis Osbeck. As the primary bioactive component in citrus fruits, it exhibits remarkable pharmacological properties including antioxidant (ORAC value ≥5000 μmol TE/g), anti-inflammatory (inhibiting COX-2 and iNOS expression), and capillary-strengthening effects (reducing vascular permeability by approximately 40%). Clinical studies have confirmed its efficacy in improving microcirculation disorders (daily dose 500-1000mg) and alleviating symptoms of venous insufficiency, with recognition as a safe dietary supplement by the EU (EFSA) and U.S. FDA (GRAS certification). Modern formulation technologies such as nanocrystallization or phospholipid complexation can enhance its bioavailability by 3-5 times, making it widely applicable in cardiovascular health, adjunctive therapy for chronic venous diseases, and functional food products.