Antioxidant effects of Phyllanthus niruri tea on healthy subjects.

Objective: To investigate the potential antioxidant effects of Phyllanthus niruri (P. niruri, Euphorbiaceae) tea on healthy subjects.

Methods: Five non-smoking, male healthy volunteers, 20 to 31 years old, were enrolled. Each subject was treated twice, following a randomized crossover fashion regarding the ingestion of P. niruri infusion (5 g/750 mL) (tea group) or 750 mL of water (control group). Fasting venous blood samples were collected prior to and at 1, 2 and 4 h after infusion drinking. Samples were tested for plasmatic gallic acid and ascorbic acid levels, erythrocytic catalase and superoxide dismutase activities, and intracellular DCFH fluorescence in granulocytes, monocytes and lymphocytes.

Results: Catalase and superoxide dismutase activities were not altered by tea ingestion. Plasma levels of gallic acid were significantly increased at 1, 2 and 4 h after P. niruri ingestion and plasma ascorbic acid at 1 h after P. niruri ingestion.

Conclusions: Ingestion of P. niruri tea is associated with a slight increase in antioxidant markers in human blood (ascorbic acid and gallic acid), which may contribute to its pharmacological effects.