Studies On The Antioxidant And Blood Lipid Regulating Effects Of Betacyanin Extract From Portulaca Grandiflora HOOK

Portulaca grandiflora Hook, also called as sunflower, is an annual succulent herb belonging to purslane family portulaca. As a typical of Betalains synthesis plant, Portulaca grandiflora Hook is widely cultivated in China. Betalains includes betacyanin and betaxanthin. Betacyanin mainly exists in the form of beta-lain glycosides. Red pigment in Portulaca grandiflora Hook extract was identified by the methods of solubility properties, TLC and spectral scanning, and quantitative determination was done by HPLC. The preparation conditions of of Portulaca grandiflora Hook betacyanin extract were determined through single factor and orthogonal design. The in vitro free radical scavenging effect, anti- plasma lipid peroxidation and anti-lard oxidation activities of Portulaca grandiflora Hook betacyanin extract were studied by colorimetry, chemiluminescence and iodometry. Activities of regulating blood lipid and antioxidant in vivo were studied by using the high fat diet-induced hyperlipidemia rat model. The results were as follows:1. The red pigment in Portulaca grandiflora Hook extract was identified as betacyanin by analyzing solubility properties and TLC and UV-Vis Scanning spectroscopy analysis, however the structure type needs further identification.2. The optimal preparation conditions of betacyanin from young trail of Portulaca grandiflora Hook were determined through orthogonal design as: ratio of solid to double distilled water 1:10, pH 7.0, and extraction temperature 45℃. The extracting rate of Portulaca grandiflora Hook betacyanin was 7.44% under these conditions.3. Portulaca grandiflora Hook betacyanin extract showed stronger scavenging effects on superoxide anion free radical (O₂^-·), hydroxyl free radical (OH) and 1,1-diphenyl-2-picrylhyrazyl free radical (DPPH·), and its activities were stronger than vitamin C. The anti-lipoperoxidation ability of betacyanin in plasma was sig- nificantly higher than that of vitamin C, and and the effects increased with the increase of concentration. Betacyanin possessed effective inhibition effecs on lard oxidation corruption, but compared to vitamin C of the same concentration (0.005mg/mL) , it had no obvious difference. The free radical scavenging effects and antioxidation ability of betacyanin extract were related to its betacyanin content.4. Portulaca grandiflora Hook betacyanin extract could significantly reduce total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol(LDL-C), apolipoprotein B(ApoB), markedly increased high density lipoprotein cholesterol (HDL-C) and apolipoprotein A (ApoA) in the serum of hypercholes-terolaemic ratst. Portulaca grandiflora Hook betacyanin extract decreased significantly atherosclerosis index (AI₁, AI₂), indicating it has atherosclerosis preventive effect.5. Portulaca grandiflora Hook betacyanin extract effectively reduced lipid peroxidate malony dialdehyde (MDA) content in the serum and liver of hyper-cholesterolaemic rats, markedly increased the superoxide dismutase (SOD) activity and glutathione peroxidase (GSH-Px) activity in serum and liver of hy-percholesterolaemic rats. It shows that Portulaca grandiflora Hook betacyanin extract had significant antioxidation effects in vivo, and its effects compared to inosi-tol nicotinate were equivalent.Conclusion: Portulaca grandiflora Hook betacyanin extract has strong free radical scavenging, anti- plasma lipid peroxidation and anti-lard oxidation abilities in vitro. It can also significantly regulate lipids through decreasing atherosclerosis index, reducing the rat plasma lipid peroxidation and enhancing antioxidant capacity in vivo.