Antioxidant and neuroprotective activities of Mogami-benibana (safflower, Carthamus tinctorius Linne)

Free radical scavenging activity of the extracts of petals (bud, early stage, full blooming and ending stage), leaf, stem, root and seeds of Mogami-benibana (safflower, Carthamus tinctorius Linne), the contents of the major active components of carthamin and polyphenols, and neuroprotective effect of the petal extracts and carthamin in the brain of mice and rats were examined. Water extracts of Mogami-benibana petals scavenged superoxide, hydroxyl and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and singlet oxygen. The scavenging activities of the extract of safflower petals with various colors showed the order of orange, yellow and white from high to low. This order is consistent with the contents of carthamin, which is a pigment of orange color and is found highest in orange petals and lowest in white petals. There was also a relationship between DPPH radical scavenging activity and carthamin content in the petal extracts of safflower. The neuroprotective effects were examined in cellular and animal models. Mogami-benibana petal extract inhibited glutamate-induced C6 glia cell death, significantly decreased the formation of malondialdehyde in mouse cerebrum, and inhibited the increase in thiobarbituric acid reactive substances and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in the cerebral cortex of rats subjected to an injection of FeCl(3) solution into the sensory motor cortex. Carthamin showed similar effects in inhibiting 8-OHdG by the petal extract in rats. These results suggest that the petal extract of Mogami-benibana has free radical scavenging activity and neuroprotective effect and carthamin is one of the major active components.