Antioxidant, free radical scavenging and liver protective effects of friedelin isolated from Azima tetracantha Lam. leaves

► In vitro and in vivo antioxidant and free radical scavenging activities of friedelin. ► Friedelin scavenged the DPPH, hydroxyl, nitric oxide and superoxide radicals. ► Friedelin restored the levels of antioxidant enzymes in CCl4 treated rats. ► Friedelin showed good antioxidant, free radical scavenging and liver protective effects.