Antihypertensive effect of lemon juice squeezed residue on spontaneously hypertensive rats

To determine the effective use of 'lemon juice squeezed residue' (LJSR), which contains many functional ingredients, we administered a diet containing 5% LJSR to spontaneously hypertensive rats (SHR) and investigated its hypotensive and oxidative stress-reducing effects. The flavonoid and coumarin contents of LJSR were measured : hesperidin, eriocitrin, and auraptene were detected. Increased systolic blood pressure was gradually reduced in the LJSR-treated group (LJSR group) and was significantly lower when compared with the control group at 4, 6, 8, 10, and 12 weeks. The urinary levels of 8-hydroxy-2'-deoxyguanosine and isoprostane were significantly lower in the LJSR group compared with the control group. The antioxidant activities of LJSR are associated with the actions of flavonoids and coumarin, which act as radical scavengers. These results suggest that LJSR could be used commercially as an antihypertensive food.