Study On The Complex Antioxidants Of Galleria Japonica And Prickly Pear Natural Extracts

Both Galla chinensis and Rosa roxburghii belong to the characteristic natural resources of Guizhou Province.The main active ingredient in Galla chinensis is tannic acid,and Rosa roxburghii is rich in a variety of biologically active substances and rich in nutrients.The extracts of both plants have multiple functions such as scavenging free radicals and anti-oxidation.In this paper,we used high-purty tannic acid from Galla chinensis and Vitamin C(V_C)and Superoxide dismutase(SOD)in Rosa roxburghii freeze-dried powder extracted by ultrasound(dehydrated from Rosa roxburghii fruit)to study the complex antioxidation.The experiment uses single factor research and response surface analysis to determine the best extraction process for V_C.At the same time,the thermal denaturation method and the acetone graded precipitation method were used to extract SOD to determine the best extraction process for SOD.In order to explore the anti-oxidant activity of single-component and compound substances in the non-oil system of tannic acid from Galla chinensis extract and V_Cand SOD from Rosa roxburghii extract,established by DPPH(1,1-diphenyl-2-picrylhydrazyl)model,ABTS(2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)model,FRAP model(Ferric reducing antioxidant potential).Using FTC(Ferric thiocyanate)method to determine the ability of three antioxidants to inhibit the peroxidation of linoleic acid in the oil system.At the same time,the synergistic antioxidant effect of tannic acid with V_Cand SOD was evaluated by isobologram,and the optimal combination in oil system and non oil system was determined.The results of this test provide a theoretical reference for the research on the synergistic antioxidant activity of Galla chinensis and Rosa roxburghii series and the development of compound antioxidants.The specific research results were as follows:1)In this experiment,through single factor experiment and response surface analysis,the best extraction process for V_Cwas determined as follows:2%metaphosphoric acid extraction solvent,extraction time 20 min,liquid-to-material ratio 28:1 m L/g.The extracted content of V_Cobtained under these conditions was125.76±1.58 mg/g.In the experiment of extracting SOD by thermal denaturation,the best treatment conditions are extraction temperature 60?,extraction time 15min,and SOD enzyme activity was 2708±70 U/g.2)In the non-oil system,the IC₅₀values of tannic acid,V_C,SOD in scavenging DPPH free radicals were 11.68±0.07 mg/L,38.21±0.39 mg/L,73.56±1.16 mg/L;tannic acid,V_C,SOD The IC₅₀values for removing ABTS free radicals are 3.18±0.11mg/L,21.30±0.43 mg/L,23.40±0.37 mg/L,respectively.When the sample reached the maximum concentration set in the test,the FRAP values of tannic acid,V_Cand SOD were 3413±31.03?mol/L?1502±35.88?mol/L and 1003±33.03?mol/L respectively.In the oil system,the inhibition rates of linoleic acid oxidation of tannic acid,V_Cand SOD were 90.19%±0.84%,11.84%±1.15%and 3.17%±0.18%respectively.3)Using isobologram analysis method,free radical scavenging test was carried out in non lipid system.The results showed that the effect points of tannic acid and V_C,tannic acid and SOD in DPPH free radical scavenging test were below the additive line and 95%confidence limit,and the interaction index(?)was less than 1.The order of synergism of tannic acid-V_Ccomplex was 1:3>1:6>9:1>1:1=1:9>6:1>3:1,and the orderofsynergismoftannicacid-SODcomplexwas1:12>1:6>1:3>8:3>2:3=4:3>16:3.The results showed that the effect points of tannic acid-V_C,tannic acid-SOD in ABTS free radical scavenging test were below the additive line and 95%confidence limit,and the interaction index(?)was less than 1.The order of synergism of tannic acid-V_Ccomplex was 1:9>9:1>6:1=1:3>1:6>3:1>1:1,and the order of synergism of tannic acid-SOD complex was1:12>16:3>8:3>1:6>4:3>1:3>2:3.The results showed that tannic acid,V_Cand SOD had synergistic antioxidant effect in non oil system.4)The results showed that the inhibition rates of linoleic acid oxidation were60.23%±1.55%,60.47%±1.02%,53.06%±0.65%,34.73%±0.66%,19.58%±1.19%,7.58%±0.26%and 4.17%±0.55%when the ratio of tannic acid and V_Cwas 9:1,6:1,3:1,1:1,1:3,1:6 and 1:9,respectively.The inhibition rates of linoleic acid oxidation were 94.58%±2.21%,82.66%±4.95%,55.81%±2.37%,39.93%±0.69%,21.47%±0.72%,17.58%±3.11%,7.54%±0.55%at 16:3,8:3,4:3,2:3,1:3,1:6 and1:12,respectively.The results showed that there was no synergistic effect between tannic acid and V_Cin the oil system,but tannic acid and SOD had synergistic anti lipid oxidation effect.