Differences In Anti-lipid Peroxidation Activity Of L-,D- And Racemic Astaxanthin

Astaxanthin is a highly active antioxidant carotenoids, with a variety of biological functions. Because of the unique molecular structure of astaxanthin, there are many isomers. Wherein the antioxidant activity differences in the degree of esterification and different geometries of astaxanthin has been a lot of research. There only some inference about difference in antioxidation activity of three kinds of astaxanthin stereoisomers.Previously, our laboratory used chemical and caenorhabditis elegans models to study antioxidant and anti-aging activities of three kinds of astaxanthin stereoisomers, results showed that different astaxanthin stereoisomers exist differences, but need more models validation and further study. In this study, linoleic acid model, rat liver mitochondria and red blood cell model were used to investigate anti-lipid peroxidation activity of 3S,3?S(S)?3R,3?R(R) and mixture astaxanthin. The main contents and results are as follows.(1) Preparation of S, R and mixture astaxanthin and the purity and structural identification. Homogenate grinding technology and ultrasonic extraction technology to extract pluvialis algae and yeast Phaffia astaxanthin, the use of saponification, column chromatography, thin layer chromatography, recrystallization, vacuum concentration, freeze drying method to prepare purity of about 95% of left-handed and right-handed astaxanthin monomer. By CHIRALPAK? IC chiral immobilized fiber column high performance liquid chromatography(HPLC) analysis, the rain pluvialis, Phaffia yeast extract astaxanthin and synthetic astaxanthin, respectively L(3S,3?S), D(3R,3?R) and mixed(3S,3?S: 3S,3?R: 3R,3?R?1:2:1) forms.(2) Use linoleic acid model to study anti-lipid peroxidation activity differences of three kinds of astaxanthin stereoisomers. Iron thiocyanate method and thiobarbituric acid method linoleic acid lipid peroxidation, results showed that three kinds of three-dimensional configuration of astaxanthin could significantly delay the auto-oxidation of linoleic acid, and can significantly reduce Fe2+ under the action of linoleic acid oxidation product malondialdehyde(MDA) content. IC50 value of auto-oxidation of linoleic acid of S, R and mixed astaxanthin were 142.02 ?M, 138.51 ?M and 208.17 ?M, IC50 value of MDA were 33.22 ?M, 34.96 ?M, 39.76 ?M. S, R were no significant difference(p> 0.05) in both the inhibition, but significantly stronger than the mixed astaxanthin(p<0.05).(3) Influence effects of three kinds of astaxanthin stereoisomers on rat liver mitochondrial lipid peroxidation under AAPH action. In AAPH oxidative stress, the degree of mitochondria swelling increases over time, the oxidation product MDA and protein carbonyl content increased significantly, while superoxide dismutase(SOD), Na+ K+-ATPase, Ca2+ Mg2+-ATPase, glutathione peroxidase(GSH-Px) activity was significantly decreased, indicating a successful model building. After protected by 40?M S, R and mixed astaxanthin, mitochondrial swelling inhibition rates were 74.55%, 62.93%, 58.08%, and therefore its inhibition ability order was: S> R> Mixed. After S, R and mixed astaxanthin pretreatment, IC50 values of MDA were 30.16 ?M, 34.43 ?M, 36.75 ?M, wherein S inhibition was significantly stronger than mixed astaxanthin(p<0.05), R and S and mixed were not significantly different(p>0.05). After S, R and mixed astaxanthin pretreatment, protein carbonyl IC50 values were 27.29 ?M, 26.36 ?M, 34.69 ?M, S and R inhibition there was no significant difference(p>0.05), but were significantly stronger than mixed astaxanthin(p<0.05). After three kinds of astaxanthin stereoisomers pretreatment, significantly increase the role of various liver mitochondria under AAPH enzyme activity(SOD, Na+ K+-ATPase, Ca2+ Mg2+-ATPase and GSH-Px), there was no significant difference(p> 0.05) between the three stereoisomers.(4) Influence effects of three kinds of astaxanthin stereoisomers on erythrocyte lipid peroxidation on the role of H2O2. In H2O2 oxidative stress, a significant increase in the rate of hemolysis, red blood cell membrane oxidation product MDA, NO generation amount also increased significantly, significantly reduced glutathione(GSH) content and SOD enzyme activity. After S, R and mixed astaxanthin pretreatment, significantly inhibited hemolysis, in which S and R was no significant difference(p>0.05), but were significantly higher than mixed astaxanthin(p<0.05). Three kinds of astaxanthin stereoisomers could significantly increase the GSH content, and its protection ability order was S> R> mixed astaxanthin, and there were significant differences(p<0.05) among the three. After S, R and mixed astaxanthin pretreatment, can significantly reduce erythrocyte membrane MDA and NO content under the role of H2O2, and improve SOD enzyme activity, but there was no significant difference(p>0.05) between the three.