Free Radical Scavenging, Antitumor and Anticarcinogenic Activity of Gossypin

Antioxidant, antitumor and anticarcinogenic activity of gossypin (3,5,8,3′,4′-pentahydroxy-7-O glucosyl flavone) was carried out. The compound needed for 50% inhibition of superoxide, hydroxyl and nitric oxide radicals was 3 μg/ml, 41 μg/ml and 12 μg/ml, respectively. Gossypin also impart 50% inhibition at concentrations 37 μg/ml and 43 μg/ml, respectively for in vitro lipid peroxidation. The compound shows IC ₅₀ of 30 μM, 42.5 μM and 45.1 μM concentrations in L 929, HT 29 and K 562 cell lines in 72 hrs MTT assay. The compound shows a zone of inhibition of 8 mm in topo I and topo II inhibition assay in Saccharomyces ceriviseae mutant cultures. It reduces the tumor burden in solid tumor harboring animals (p<0.001) and effectively inhibits the formation of new blood vessels on tumor mass. 20 mg/kg b.wt of gossypin increase the life span of ascites tumor harboring animals (100%) and (164.7%) respectively by oral and intraperitoneal administration of the drug. Gossypin reduced the incidence of papilloma formation and papilloma/mouse in DMBA/croton oil induced skin papilloma.