Study On The Antioxidant Activity Of ?-carotene From Blakeslea Trispora

?-carotene is a kind of carotenoids,which has good antioxidant activity because of its olefin structure.The Blakeslea trispora is receiving increasing attention since its higher industrial production of carotenoids.In this paper,we evaluated the antioxidant activity of of?-carotene,which has practical significance for its further application as antioxidants and drugs.1.The kinetics of antioxidant activity of?-carotene:We evaluated the scavenging free radical ability of?-carotene by DPPH method to study the antioxidant activity with different concentrations at different temperatures.What's more,the related kinetic data,such as EC₅₀,Ea,and K,were calculated.The results showed that the antioxidant activity of?-carotene at 37?was higher than at 25?at the same concentration.And the antioxidant activity increases with increasing concentration at the same temperature.In addition,The reaction temperature had a great influence on the antioxidant activity,but the initial concentration had no effect on the activity by calculation.2.The antioxidant activity of?-carotene in vitro:The?-carotene had well scavenging activity to DPPH·,·OH and O₂^-·at the concentration from 20 to 100?g/mL,and follow the relationship of dose-response.The highest scavenging rate was reached to 71.22%,29.81%and 65.28%respectively.The reducing power of?-carotene was lower than vitamin c.3.The antioxidant activity of?-carotene in vivo:The?-carotene group improved the antioxidant activity of transgenic zebrafish.The three relative concentration?25,50,100?g/mL?of the antioxidant capacity were reached to 30.43%,53.62%and 73.91%,Adding the right amount of?-carotene could help the growth of zebrafish with fluorescent skin.4.Protective effect of?-carotene on oxidative damage of liver induced by hydrogen peroxide in zebrafish:The liver injury model was induced by proper concentration of H₂O₂,and?-carotene of 10,20,and 40?g/mL were used to protect it.The levels of alanine aminotransferase?ALT?,aspartate aminotransferase?AST?,superoxide dismutase?SOD?and malondialdelyde?MDA?were measured by the spectrophotometric method.The pathological changes of the liver tissues were observed by HE staining.The relative mRNA expression levels of SOD,CAT,GSTP2 and Nrf2 were assessed by real time quantitative PCR.The results showed that H₂O₂ elevated the levels of ALT,AST and MDA,while reduced the level of SOD after 48 hours.Compared with model group,?-carotene decreased the levels of ALT,AST,and MDA,improved the activity of SOD.?-carotene ameliorated the hepatic pathological changes.?-carotene could significantly increase the relative expression level of SOD,CAT,GSTP2 and Nrf2.?-carotene had protective effects on liver injury induced by H₂O₂ in zebrafish.