Studies On The Antioxidant Stability And Radio-protective Effect Of Betalain

The antioxidant stability of betalain was researched systematically and the radioprotective activity of betalain in mice irradiated by ⁶⁰Co gamma ray(6.0 Gy,at a dose of 1.5 Gy.min^-1) in vivo was conducted in this paper.Betalain was evaluated under different pH,temperature.This study was also conducted to the changes of the anti-oxidative stabilities of betalain when the environment had changed simultaneously.The results showed that the stabilities of betalain were good.It is worth to develop in food industry.The results suggested that different pH had no significant influence on the anti-oxidative stabilities of betalain.But boiling water had significant influence on the anti-oxidative stabilities of betalain.Betalain were transferred to Sephadex LH-20 column and separated by elution ultrafiltered wanter adjusted to pH 5-6 with formic acid.Different fractions(red-violet betacyanins and yellow betaxanthins) were collected and then freeze-dryed,the result shows that the main antioxidant composition of betalain were the red-violet betachyanins.To investigate the irradiated by ⁶⁰Co gamma ray in vivo,We established the irradiation damage model of ICR mice by ⁶⁰Co gamma ray(6.0 Gy,at a dose of 0.6Gy/min) in vivo. The mice were randomly divided into five groups,including the control group(â… ) and four ⁶⁰Co groups:model groupâ…¡,high dose groupâ…¢(80mg/kg),middle dose groupâ…£(20 mg/kg),low dose groupâ…¤(5mg/kg)).We counted the white cells,calculated the spleen and thymus indices of the mice,measured the formation of micronuclei,Then we measured the activities of superoxide dismutase(SOD),glutathione peroxidase(GSH-px) and the amount of malondialdehyde(MDA) and total antioxidative capacity(T-AOC) of the mice.So the antioxidant activity of betalain was highly resistant to the pH and temperature factors tested.The results indicated that at the dose of 6.0 Gy,the betalain could increase the spleen and thymus indices,inhibit the decrease of SOD,activities of GSH-px and CAT,T-AOC and the increase of the amount of MDA of several organs in mice with dose dependent manner.Betalain could reverse partially the irradiation-induced reduction in white blood cells,and have effect on the formation of micronuclei.But betalain has no influence on the clearance rate of charcoal particle and lymphocyte transformation test,The betalain has protective effects on mice irradiated by ⁶⁰Co in vivo.The mechanism might to its antioxidative capability.