Analysis And Antioxidant Activity Of Different Extracts From Wheat Bran

China is one of major wheat producing countries.Wheat production reached more than one hundred million tons.Wheat bran as a major processing mill by-products,annual production of more than 20 million tons.Wheat bran is rich in a variety of physiologically active substances,such as linoleic acid,vitamin E,polysaccharides, oligosaccharides,phytic acid and phenolic compounds etc.There are two major categories of substances in wheat bran,namely,phenolic compounds and polysaccharides.Studies have shown that extracts of wheat bran with anti-oxidation,free radical scavenging,anti-bacterial anti-inflammatory and other pharmacological activities.At present,the main of wheat bran used as feed with the lower economic value,just a little wheat bran were used to bread and bran protein extraction.The different parts were extracted with the solvents from weak to strong successively.Study on different extracts of anti-oxidation and free radical scavenging activity,and analysis the main active ingredients.Inclusion technology of wheat bran petroleum ether extract were researched which rich in unsaturated fatty acids on the activity and poor stability.And select the best conditions for inclusion.Its provide a basis for the comprehensive utilization of wheat bran and the wheat bran functional foods development.The main contents and results are as follows:To study the active ingredients of different wheat bran extract. Wheat bran(104℃for 4h to eliminate enzyme) as raw materials,by petroleum ether,ethanol and distilled water as the solvent step-by-step extract.Get three wheat bran extract(petroleum ether extract,ethanol extract and water extract).Their yield were 2.40±0.06(%),12.10±0.01(%) and 30.20±0.05(%).Petroleum ether extract was analyzed by GC-MS.The result showed that fatty acids were the main components in the petroleum ether extract.In particular,unsaturated fatty acid content of high-level maximum,accounted for 95.89%of total fatty acids.The total phenol and flavonoids contents of ethanol extract were determined by reagent Folin-Ciocalten and NaNO₂-AlCl₃ method under alkaline conditions.The total phenol and flavonoids yields of ethanol extract were 31.39±0.03(mg/g) and 14.96±0.04(mg/g).Ethanol extract was further analyzed by LC-DAD-ESI-MS.The result showed that the ethanol extract containning ferulic acid,p-coumaric acid,syringic acid,gentisic acid and caffeic acid.They were provide a theoretical basis for the activity test of wheat bran ethanol extract,of water extract of wheat bran in the The polysaccharide content of wheat bran water extract were determined by phenol-sulfuric acid method.The resulted showed that polyaccrid content of water extract was 42.40±0.05(%).To study of wheat bran extract(petroleum ether extract,ethanol extract,water extract) on the three common free radical(DPPH·,·OH,O₂^-) scavenging capacity by ultraviolet spectrophotometry,O-phenanthroline method and pyrogallol autoxidation method.The results show that three wheat bran extract have a clear capacity on free radical(DPPH·,·OH,O₂^-).For the DPPH·,the ethanol extract had the most removal competent.When the concentration of 1.9mg/mL,the clearance rate was 93.0%,and the semi-inhibition rate of radical scavenging capacity(IC₅₀) was 0.86mg/mL.The petroleum ether and water extract have the relatively weak capacity to remove DPPH·,and their IC₅₀ values were 1.44mg/mL and 1.90mg/mL.However,the removal of the three extracts were significantly less than the capacity of Vc(IC₅₀ was 0.009).For·OH,bothe petroleum ether extract and ethanol extract have better to remove capacity.When the concentration of 4.0mg/mL,the clearance rate was 89.74%to petroleum ether extract and 98.20%to ethanol extract,their IC₅₀ values were 1.94mg/mL and 1.88mg/mL,the scavenging capacity was closed to Vc(IC₅₀ values was 0.255).But the water extract less able to clear·OH,its highest clearance rate was only 30.08%.For O₂^-,the water extract's scavenging capacity better than the other two extracts.When the concentration of 4mg/mL,the clearance rate was 92.01%,IC₅₀ values closed to Vc(IC₅₀ was 0.190) was 1.12mg/mL.Both the petroleum ether extract and ethanol extract have a clear role to superoxide anion.Their IC₅₀ values were 2.72mg/mL and 3.26mg/mL.To study antioxidant activity of the extracts(petroluem ether extract,ethanol extract,water extract)to fresh lard and soybean oil by enhanced oxidation oven.The results showed that the petroluem ether extract and ethanol extract to lard were better antio-oxidant,and 0.2% petroluem ether extract had the best antioxidant to lard.The peroxide value(POV) was 0.1051 in the 12^th day,much lower than the blank POV value(0.5136).Three concentrations of ethanol extract's POV values were 0.2165,0.3277,0.1656 in the 12^th day.Their POV values were lower than the blank POV value(0.5136).The antioxidant effect of water extract to lard are poor.Both 0.10%and 0.20%water extract's POV values were 0.5435 and 0.5753 in the 12^th day.The POV values were higher than the blank POV value(0.5136).The antioxidant effect to soybean oil.Three different concentrations of extract have better anti-oxidation to soybean oil.0.02%petroluem ether extract,0.1%ethanol extract and 0.1%water extract's POV values were 0.0810,0.0835 and 0.0797 in the 12^th day,much lower than the blank POVvalue(0.2525),and closed to BHT POV value(0.0637).To study inclusion technology of petroluem ether extract toβ-cydodextrin(β-CD).Inclusion compound was got by saturation solution method.The test result of single factor and orthogonal test all indicated that the optimal inclusion condition was:the ratio ofβ-CD to PEEWB was 2:1,stirring for 3 hours at 40℃.The average recovery for the inclusion complex was 71.73%.The inclusion complex as massive crystal in the scanning electron microscopy.There were not only the emergence of new peaks(1339.88cm^-1,1155.68cm^-1,1026.65cm^-1),but also the lacation of peak movement in infrared spectra.β-CD hydroxyl(OH) streching vibration displacement from 3398.25cm^-1 to 3328.73cm^-1.Infrared spectra showed that between petroluem ether extract and the hydroxy-β-CD have the van der waals force which led hydroxy moving to the low wave number.All the results proved to the formation of inclusion complex and the technology was stable and feasible.The method saturation solution for preparation inclusion was simple and convenient with lower cost and the request to equipment was fewer.