Studies On Extraction And Antioxidant Activity Properties Of Five-flower Tea

Five-flower Tea,a kind of Cantonese herbal tea,is mainly made from chrysanthemum,honeysuckle,Sophora japonica L.,seville orange flower and flos lablab albus.The quality of materials,the compatibility of different materials and the extraction of main functional ingredients affect the production cost and the product's quality directly;while the efficacy of the product is the most important concern for the consumers.To this end,the study has carried out the following research:1.The content of the total flavonoids was used as the main evaluation criterion for the quality of the materials,and materials of“Five-flower Tea”from different sources was evaluated.The results showed that the honeysuckles from Xiangtan,Hunan and Xiushan,Chongqing contained a higher content of total flavonoids,and their total flavonoids were 99.15±3.44 mg RE/g and 98.40±8.32 mg RE/g,respectively.The varieties with higher total flavonoids of chrysanthemum were Coreopsis tinctoria Nutt.and chrysanthemum bud,and their total flavonoids were124.36±5.55 mg RE/g and 112.34±7.23 mg RE/g,respectively.Wild chrysanthemum had the lowest flavonoid content,which was only 35.73±2.52 mg RE/g.The Sophora japonica L.from Quanzhou,Guangxi contained highest content of total flavonoid,which was 291.80±11.87 mg RE/g.While the lowest content of flavonoid of Sophora japonica L.was found in Dalian,Liaoning with only 89.49±1.38 mg RE/g.The flos lablab albus from Bozhou,Anhui had highest content of total flavonoid?19.91±1.53mg RE/g?,while the lowest content of of flavonoid of flos lablab albus was found in Yulin,Guangxi?11.36±1.22 mg RE/g?.The seville orange flower from Jiaxing,Zhejiang had highest content of total flavonoid,which was 13.17±0.98 mg RE/g.2.The effect of pulverization on the extraction of“Five-flower Tea”was studied.The results showed that the crushed materials of“Five-flower Tea”were conducive to the extraction of flavonoids.Under the same conditions,the extraction rates of flavonoids from different materials were significantly increased.The extraction rates of flavonoids from Sophora japonica L.,honeysuckle,seville orange flower,Chrysanthemum and flos lablab albus were increased by 115.57%,46.64%,28.01%,22.89%and 16.29%,respectively.The extraction rate of flavonoids increased by35.04%after five kinds of tea materials were mixed and crushed.3.Taking the extraction rate of flavonoids as the index,three extraction methods of“Five-flower Tea”were optimized by orthogonal design.The optimum extraction conditions for the atmospheric water extraction were as follows:ratio of material to liquid was 1:100?g/mL?,extraction temperature was 100?,extraction time was 120min.Under this optimized condition,the extraction rate of flavonoids was 62.63%.The optimum extraction conditions for the reflux extraction were as follows:extraction temperature was 100?,extraction time was 100 min,ratio of material to liquid was 1:100?g/mL?.Under this optimized condition,the extraction rate of flavonoids was 74.73%.The optimum extraction conditions for the pressurized extraction were as follows:extraction temperature was 113?,extraction time was 22min,ratio of material to liquid was 1:120?g/mL?.Under this optimum condition,the extraction rate of flavonoids for“Five-flower Tea”was 90.33%.The extraction rate of flavonoids by the pressurized extraction was the highest among the three extraction methods.4.The DPPH radical scavenging assay and the AAPH-induced erythrocyte hemolysis assay were conducted to evaluate the antioxidant properties of the five kinds of flower extracts and the compound?chrysanthemum 50%,Sophora japonica L.18%,flos lablab albus 15%,seville orange flower 12%,honeysuckle 5%?in a certain proportion.The synergistic antioxidant activity of the materials of“Five-flower Tea”was also studied.The results showed that both the extracts and the compound had a certain degree of antioxidant capacity.According to the half clearance rate of free radicals(IC₅₀),the order of antioxidant capacity in DPPH system was as follows:Compound(IC₅₀=97.83?g/mL)>Sophora japonica L.(IC₅₀=98.63?g/mL)>chrysanthemum(IC₅₀=140.79?g/mL)>honeysuckle(IC₅₀=146.35?g/mL)>seville orange flower(IC₅₀=692.24?g/mL)>flos lablab albus(IC₅₀=701.51?g/mL).Based on the“Direct Comparison Methodology”,the compound showed the strongest antioxidant capacity,indicating that the compound had a certain synergistic antioxidant effect.According to the“Addition Methodology”,the scavenging rate of the compound reached 84.54%at the concentration of 300?g/mL,which was less than the actual measured value?87.54%±0.85%?,indicating that there was a certain synergistic antioxidant effect between the five raw materials of“Five-flower Tea”.In AAPH-induced red blood cell hemolysis assay,the extracts of Sophora japonica L.and formulations showed strong inhibitory effects on hemolysis,while the extracts of honeysuckle,chrysanthemum,seville orange flower,and flos lablab albus exhibited slightly inhibitory effects,indicating that there was synergistic effect between the five kinds of flowers.When the dose was between 50and 300?g/mL,the hemolytic inhibition rate of Sophora japonica L.extract on erythrocytes was less than that of the compound.When the dose reached 300?g/mL?,the inhibition rate for Sophora japonica L.extract and the compound was77.83%±1.85%and 80.94%±1.46%,respectively.The results showed that there was a synergistic antioxidant effect between the five kinds of herb extracts.