Study On The Efficient Separation And Antioxidant Capacity Of Rosemary Antioxidants

The major objectives of this study were to investigate the high efficient seperation of rosemary antioxidants carnosic acid(CA) and rosmarinic acid(RA).and the antioxidant capacity of CA and RA were also studied in the in vivo or in vitro assay.Estabilished the high efficient separation and purification process of carnosic acid.the extraction conditions of carnosic acid from rosemary leaves and stems were studied with the pH controlled homogenate extraction technology firstly.Different technological parameter was studied during the extraction and obtained optimum extraction process.The content of carnosic acid was 24.9%(CA25) the recover yield was 93.9%under the optimum process condition. After the next two steps purification,content of carnosic acid could reach 60.5%(CA60) and 98.3%(CA98),the recover yield was 80.5%and 62.2%,respectively.These technology conditions of the carnosic acid production were simply,efficient,and suitable for the mass production.Antioxidant capacities of CA with different content of carnosic acid were studied for the first time.The determination of CA antioxidant capcity showed that all of the reducing power, and the ability to scavenge DPPH radicals and ABTS radicals were positively related with carnosic acid content.The reducing power of CA98 was greater than the artificial synthesized antioxidants(TBHQ,BHA and BHT).The scavenging DPPH radical capacity was weaker than TBHQ,but greater than BHA and BHT.The results also showed that the ability to scavenge ABTS radicals was very low,even the result of CA98 was lower than the three artificial synthesized antioxidants.And in FRAP test,the acivity of the different antioxidants sequence was TBHQ＞BHA＞CA98＞CA60＞BHT＞CA25,also indicated that CA has a strong antioxidant activity.Oxidative stability of CA on sunflower oil with different content of carnosic acid were studied campared with artifical synthesized antioxidants were studied by determination the index of primary oxidation products and secondary oxidation products,such as peroxide value, TBA,anisidine value and free fatty acid.Results showed that the antioxidant capacity of CA was lower than TBHQ,but it was greater than BHA and BHT.That is,we could substitute CA for BHT and BHA to prevent the lipid oxidation in edible oil,even with a low content of carnosic acid.Estabilished the high efficient separation and purification process of rosmarinic acid(RA), RA was purified by silica column chromatography.The optimum conditions:160-280mesh chromatographic silica gel were packed in the column,the eluent was methyl acetate,the flow rate of the eluent was 30mL/min,loading of the antioxidants were 35g/kg silica gel.The purity of rosmarinic acid was 98.1%and the recover yield was 90.5%,which obtained under the optimum.This technics was proved high efficient,low expenditure of solvent,low cost and easy to perform short-term and helped rosmarinic acid to realize green industrialization manufacture.The relative antioxidant capacity of RA campared with VE and VC were determined in four model systems including of scavenging hydroxyl radical,superoxide anion radical,DPPH radical and ABTS radical.Results also indicated the dose-dependent relation.The SC50 value of scavenging hydroxyl radical,superoxide anion radical and DPPH radical were 0.634μg/mL, 0.1073mg/mL and 0.1371mg/mL,respectively.The value of scavenging ABTS radical was 9644.and RA had more advantages over VE and VC in antioxidant capacity.RA was also evaluated for its in vivo antioxidant activity using aging mice.This study demonstrated that high-dose RA could significantly enhanced activity of SOD and CAT in serum,liver and kidney.High-dose RA could improve the acitity of GSH-Px in kidney,but had no effect on liver(P＞0.05).Results also showed that high-dose RA could decrease the content of MDA in serum,liver and kidney.These results demonstrated that RA could enhance the antioxidant enzyme activity,and derease the content of lipid peroxidation products in vivo.The effect of RA on the ultramicrostructural changes in liver and kidney were studied. Results showed that RA couled decrease the content of fat droplet in liver,and promotes the mild merging of nephric tubule microvillus.These results indicated that RA could hasten the metabolism of fat in liver,and had no side effects on kidney in mice.These results are important for better understanding about the antioxidant activities of rosemary antoxidants.This study provided useful evidence that rosemary antioxidants would have even broader prospect.