| The purpose of this study was to analyze the components and evaluate the quality of alfalfa and oat grass from different varieties from the point of view of flavonoids as the nutritional active substances,so as to lay a foundation for the application of "healthy breeding" and "precision nutrition" for livestock and poultry.Test to select the 19 different varieties of alfalfa and 18 different species of oat grass,first of all,to carry on the quantitative analysis of the flavonoids content of,using the single factor analysis of variance ethanol concentration,extraction time and solid-liquid ratio on the flavonoids content,on the basis of the application of the Design-Expert.8.0.6.1 response surface optimization,determine the best extracting flavonoids to add,to evaluate different alfalfa varieties and oats,respectively;High performance liquid chromatography was used to characterize the characteristic peaks of the components in the extract,and modern analysis techniques such as cluster analysis and principal component analysis were used to classify the samples of different varieties.The results showed that:(1)Optimization of the extraction process of flavonoids from alfalfa: the final extraction conditions were ethanol concentration of 80.45 %,solid-liquid ratio of 1:32,ultrasonic time of 33.49 min,and the content of flavonoids in alfalfa was 10.351 mg/g under these conditions.By comparing the content of total flavonoids in 19 different varieties of alfalfa,it was found that the content of total flavonoids in different varieties of alfalfa was significantly different(P < 0.001),the average content was 9.101±0.790 mg/g;Establishment of chromatographic fingerprint detection method of alfalfa trophic active substances: the final chromatographic condition was Luna C18 column(250mm*4.6mm,5 μm);Acetonitrile(A)-0.5 % phosphoric acid solution(B)was selected as mobile phase.Gradient elution;The flow rate was 1.0 m L/min.The detection wavelength was 350 nm.Column temperature25 ℃;The separation of each peak is good when the sample volume is 10 μL;Quality evaluation of 19 batches of alfalfa: The composition similarity of 19 batches of alfalfa ranged from 0.475 to 0.062,indicating that the composition difference between different varieties of alfalfa was great,indicating that the growing environment of alfalfa had great influence on the composition content.Cluster results showed that the alfalfa samples were divided into two categories,S1,S3-S6,S8-S11,S13-S16 were classified into one category,S2,S7,S12,S18,S19(WL168HQ,WL366 HQ,WL363HQ,American alfalfa,domestic alfalfa,etc.)were classified into one category.Three principal components were labeled in PCA analysis,of which the contribution rate of principal component 1 was 50.379 %.(2)Optimization of extraction conditions of flavonoids from Oat grass: the maximum extraction rate of flavonoids was determined as ethanol concentration of 81.23 %,solid-liquid ratio of 1:38 and extraction time of 26.76 minutes.At the same time,under the optimal extraction conditions,the contents of total flavonoids in oats from 18 different varieties were significantly different.The highest flavonoids content in oats from Leader was 10.151 mg/g,and the lowest flavonoids content in oats from old China was only 5.503 mg/g;Quality evaluation of 18 batches of oats: the conventional nutrients of 18 different varieties of oats were classified into super grade,first grade,second grade and third grade;Combining the feature of fingerprint technology to build tall oat grass fingerprint,combined with modern analytical technology,18 kinds of tall oat grass can be divided into 3 groups,including the first category(S15,S17,S5,S3,S16)oat the flavonoids content is low,the second category(S1,S11,S8,S18,S6,S10,S2,S4,integrated,S14)and the third class(speed 12,S13,S7)oat the flavonoids content is relatively high,the peak area of main ingredients(2)peak value is relative content is more. |
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