Antioxidative, antibrowning and antibacterial activities of sixteen floral honeys.

Commonly consumed honeys from sixteen different single floral sources were analyzed for their in vitro antioxidant capacities by several methods including DPPH, ABTS, FRAP, SASR and MDA assays. The total polyphenol contents varied among the tested honeys and were highly correlated to their antioxidant capacity values. The antioxidant capacity of Chinese milk vetch flower honeys was significantly higher than those of other flower honeys. All honeys tested were active in inhibiting the browning of apple homogenate and linden honey displayed the highest inhibition rate as 85%. When the antimicrobial activity of the investigated honeys was screened using Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli), clover honey exhibited the strongest antibacterial activity as 2.2 mg mL(-1) kanamycin equivalent inhibition.