The Dynamic Change Of Active Components And Mechanism Of Flos Lonicera Under Low Temperature Drying

Lonicera Japonica Thunb.is caprifoliaceae,is the dried flower buds or early flowers of Flos Lonicerae,as commonly used traditional C hinese medicines,possesses functions of antibacterial,anti-inflammatory,anti-oxidation,anti-virus,detoxification,Diuretic,hypolipidemic.In the early harvest,Lonicera Japonica with high moisture content,if can't be dried timely,the browning occurs easily,the appearance color and inner quality of products will be seriously affected.In this paper,the conditions of extracting active components by high-speed shearing extraction?HSSE?were optimized,and the antioxidant activity of extract was evaluated.In this paper,the fresh flower buds of Yate were used as experimental materials.The main extracting active components were extracted by HSSE,and determined by HPLC.Meanwhile the effects of different varieties,flowering phase and drying temperatures on the active compone nt content and physiological and biochemical indexes of flowers were studied.We choose 35°C as drying temperature to study the dynamic change of active components content and the activity of key enzymes in the drying process.This study provides important theoretical basis for establishing scientific and reasonable drying process,which is of important value for improving the quality of Flos Lonicerae,and has great significance to solve the problem of browning in the process of traditional C hinese medicines.The main results are as follows with analysis:1.The total extraction yield of 11 active components?neochlorogenic acid,chlorogenic acid,4-dicaffeoylquinic acid,caffeic acid,rutin,luteoloside,hyperoside,isochlorogenic acid B,isochlorogenic acid A,isochlorogenic acid C,and quercetin?were taken as index to optimize high-speed shearing extraction?HSSE?conditions for major active components from Lonicera japonica by orthogonal design.The optimal extraction conditions were 60% ethanol solution,1:25 g/m L solid: liquid ratio,10000 r/min of rotate speed,and 120 s of extraction time,the total extraction yield of the 11 active components was 35.86 mg/g.HSSE had advantages such as high yield and times saving by comparison with ultrasound assist extraction?UAE?and heating reflux extraction?HRE?.The antioxidant activity of extract was evaluated by the radical scavenging capacity of DPPH· and O₂^·,ferric reducing activity power,Vc was taken as positive control.Results showed that Lonicera japonica extracts had good antioxidant activity,radical scavenging capacity of O₂^·was higher than Vc.The correlation analysis indicated that most active components had significant correlation with antioxidant activity.2.The effects of different varieties,flower phases and drying temperature on the active components content and physiological and biochemical indexes of flowers were studied.The main extracting 11 active components,such as chlorogenic acid,isochlorogenic acid,luteoloside and so on,were extracted by HSSE,and determined by HPLC.The results showed that the total extraction ratio of of Flos Lonicerae which was dried under 35 °C was higher than that of 45°C and 55°C.The dynamic changes of physiological and biochemical indexes such as relative electric conductivity and malondialdehyde?MDA?were studied.The results showed that adversity stress of the Flos Lonicerae suffered under 35°C was less than 45°C and 55°C.Therefore,the appearance color and total active components,the co st,and the convenience were as comprehensive indicators to determine Yate Flos Lonicerae buds under 35°C for drying conditions as the best processing methods.3.The effect of drying condtion under 35°C on the appearance color and active components,physiological and biochemical indexes of Flos Lonicerae: We observed the apprance color,then active components content,dynamic changes of key enzymes and the correlation between the two in different drying stages were studied.The results demonstrated that Flos Lonicerae with bright green and low browning,and better appearance quality under low temperrature.The content of chlorogenic acid and luteoloside fluctuated and reduced as the drying time during the whole drying process.The activity of PAL,PPO,PO D follow the same trends as the content of phenolic acid compound and flavonoid.The content of chlorogenic acid,luteoloside and the activity of PAL had significant correlation,which was highly significant correlation with the activity of PPO.The results showed that 35°C as the drying temperatue play a key role in the dynamic changes of key enzyme activities,which reduce the occurrence of browning and maintain the active components content of Flos Lonicerae.