Phenolic Profiles and Antioxidant Capacities of Chinese Unifloral Honeys from Different Botanical and Geographical Sources

Abstract

Honey has been acknowledged worldwide as a good source of natural antioxidants. Chemical properties of total phenolics and flavonoids of 33 Chinese unifloral honeys from nine different floral sources were investigated. Antioxidant activities including 1, 1-diphenyl-2- picrylhydrazyl radical (DPPH·) scavenging, superoxide anion radical (O2−·) scavenging, hydroxyl radical (·OH)-scavenging activities, and reducing powers were evaluated. The results indicated that total phenolic content (TPC) ranged from 10.43 to 149.6 mg of PCE/100 g, while total flavonoid content (TFC) ranged from 9.41 to 102.1 mg QE/100 g. Positive correlations between radical-scavenging activities and, respectively, TPC values and TFC values were found. Remarkable variations in antioxidant properties, TPC, and TFC values were demonstrated in hydrophilic extracts of honeys from different botanic and/or geographic sources. The current findings will provide useful information for evaluating the food quality of Chinese honey and for educating consumers to choose specific honey lines for their specific health-promoting effects.