Abstract: Water extract of Clerodendranthus spicatus was successively fractionated using 3 different solvents to provide petroleum ether extract (PE),chloroform extract (CE),ethyl acetate extract (EAE) and water extract (WE).Different antioxidant assays including OH·,O₂^-·,DPPH· scavenging activity,reducing power,metal chelating activity,anti-reactive oxygen species (anti-ROS) activity and effects on FeSO₄ and H₂O₂ -induced MDA and GSH-Px production increase were employed to evaluate the antioxidant activities of four extracts.The inhibition rate of mitochondrial swelling induced by Fe²⁺-L-Cys in vitro was employed to evaluate the protective effects on mitochondrion.The results showed that all the 4 different extracts had the ability of scavenging DPPH·,O₂^-·,,·OH and chelating Fe²⁺,anti-ROS in vitro, significantly lower the levels of MDA,rised the levels of GSH-Px in renal homogenate and inhibited the renal mitochondria swelling,in concentration dependent manner.The results provided a basis for C.spicatus to be used in the treatment of renal disease.

Key words: Clerodendranthus spicatus, antioxidant activity, metal chelating activity, reactive oxygen species, mitochondrial swelling