Anthocyanins in different types of black rice are different and their in vivo antioxidant activity is poorly
studied. In this study, nine anthocyanins were detected by high performance liquid chromatography
(HPLC) and eight of them were identified by ultra performance liquid chromatography/time-of-flight
mass spectrometry (UPLC/Q-TOF-MS) in black rice. The in vivo antioxidant activity of the black rice
extract containing 41.69% of anthocyanins was determined by the model of KBrO3-induced renal injury in
mice. KBrO3 caused serious renal injury, with a significant increase in serum creatinine (14.37 ± 0.27 mg/
mL versus 8.80 ± 0.38 mg/mL) and blood urea nitrogen (BUN, 625.56 ± 42.62 mg/L versus
348.49 ± 14.90 mg/L) levels. KBrO3 could also cause oxidative stress in the kidney, with a significant
increase in renal xanthine oxidase (XOD), malondialdehyde (MDA) and nitric oxide (NO) levels. Pretreatment
with the anthocyanin-rich black rice extract remarkably reduced the levels of serum creatinine
and BUN and the levels of renal XOD, MDA and NO. The protective effects were due to the free radical
scavenging capacity of the anthocyanins.