Antioxidant activity of Citrus fruits

• The antioxidant compounds of Citrus fruits were reviewed.
• The classical and new methods for antioxidant activity evaluation were summarized.
• The underlying mechanisms of antioxidant compounds were revealed.
• The factors influencing the antioxidant activity of Citrus fruits were discussed.
• The suggestions for future study about Citrus fruits were presented.

Citrus is well-known for its nutrition and health-promotion values. This reputation is derived from the studies on the biological functions of phytochemicals in Citrus fruits and their derived products in the past decades. In recent years, the antioxidant activity of Citrus fruits and their roles in the prevention and treatment of various human chronic and degenerative diseases have attracted more and more attention. Citrus fruits are suggested to be a good source of dietary antioxidants. To have a better understanding of the mechanism underlying the antioxidant activity of Citrus fruits, we reviewed a study on the antioxidant activity of the phytochemicals in Citrus fruits, introduced methods for antioxidant activity evaluation, discussed the factors which influence the antioxidant activity of Citrus fruits, and summarized the underlying mechanism of action. Some suggestions for future study were also presented.