Isolation And Identification Of Flavonoids From Zanthoxylum Armatum DC Ethanol Extract And Taste Research

In this paper,Zanthoxylum armatum DC peel was used as raw material,and ethanol was used as extraction solvent and ultrasonic to assist in extracting total flavonoids from Zanthoxylum armatum DC peel,which was isolated,purified and identified,and then analyzed by electronic tongue.At the same time,the antioxidant capacity of the extract of Zanthoxylum armatum DC.under different drying methods was studied,which provided theoretical support for the extraction of flavonoids and the choice of post-harvest treatment.The main contents and conclusions of the study are as follows:(1)Comparative study on the antioxidant activity of the ethanol extract of Zanthoxylum armatum DC.under different drying methods,the results showed that the antioxidant activity of Zanthoxylum armatum DC extract increased first from May 30 to July 18,on July 4,reached the maximum for ABTS.+,DPPH.,hydroxyl radical scavenging rate and total reducing power.The antioxidant activity and total reducing power of the extract of Zanthoxylum armatum DC under two drying modes are strong.When the volume concentration is 250uL/mL,the natural dried and constant-temperature dried extract of Zanthoxylum armatum DC.ABTS.+,DPPH.The scavenging rates of hydroxyl radicals were: 77%,98%,63% and 72%,96%,50%,respectively.(2)Ultrasonic extraction of total flavonoids from the peel of Zanthoxylum armatum DC,the effects of ethanol concentration,extraction time,ratio of material to liquid and extraction temperature on the extraction yield of total flavonoids in the peel of Zanthoxylum armatum DC,respectively,were optimized by orthogonal experiment.The flavonoids content of Zanthoxylum armatum DC.under different drying methods were determined.The results showed that the order of the four factors on the yield of total flavonoids in Zanthoxylum armatum DC peel was: material-liquid ratio> extraction temperature> extraction time> ethanol concentration.The optimal extraction combination of total flavonoids in Zanthoxylum armatum DC peel was determined as: material-liquid ratio 1:40;extraction temperature 70 °C;extraction time 60 min;ethanol concentration 60%.Under this combination condition,the total flavonoid yield in Zanthoxylum armatum DC peel was 1.29%..The effect of different drying methods on the yield of total flavonoids in Zanthoxylum armatum DC peel was: constant temperature drying>natural drying,and From May 30 to July 18,with the extension of the picking period,the content of total flavonoids in the peel of Zanthoxylum armatum DC increased first and then decreased.On June 27,the content of flavonoids was the highest.(3)The flavonoids in the peel of Zanthoxylum armatum DC were purified by silica gel column chromatography and preparative chromatography.Two kinds of flavonoids with 98% purity were isolated from the peel and identified by infrared,mass spectrometry and nuclear magnetic resonance.It is: Compound A: 3,5,7-trihydroxy-8,4'-dimethoxyflavone,which is isolated for the first time in Zanthoxylum armatum DC;Compound B: rutin.(4)Using the extracts of 22 commonly used traditional Chinese medicines with different tastes as experimental materials,using the principal component analysis and discriminant factor analysis of electronic tongue to establish the discrimination model of Chinese herbal medicines,and judging the taste of the flavonoids,the results show that The electronic tongue can distinguish and distinguish different medicinal materials and different medicinal materials with the same taste.The recognition index is above 93.The main contribution factors are the first principal component and the second principal component.The sum of the contribution rates is More than 97%.The discriminant model established by selecting sourness,bitterness and salty taste has a cross-validation score higher than 75 and a correct rate of 100%.The model is accurate and reliable.The bitterness analysis of the extracted rutin and 3,5,7-trihydroxy-8,4'-dimethoxyflavone proved that rutin has a bitter taste and its discriminant index is 85,3,5,7-trihydroxy-8,4'-dimethoxyflavone does not have acid,bitter,sweet taste.