Analysis Of Effective Composition And Optimization Of Flavonoids Extraction Technology Of Glycyrrhiza Uralensis

Glycyrrhiza uralensis is a perennial herb of leguminous family.It is an important Mongolian medicinal material with homology of medicine and food.It is rich in flavonoids,saponins,sugars and other effective components.The active components of flavonoids include schaftoside,isoschaftoside,nobiletin,isovitexin,etc.,which can regulate immunity,prevent and cure viruses,treat non-alcoholic fatty liver,inhibit inflammation,and fight cancer.It was found that the highly efficient nitrogen-fixing nodules formed in the root of Glycyrrhiza uralensis had a great effect on the growth and development of licorice plants and the accumulation of active components in the root.The highly efficient nitrogen-fixing rhizobium could improve the contents of total flavonoids,sugars,saponins and other substances in the root of Licorice.However,the root of Glycyrrhiza uralensis planted in Naiman area of Inner Mongolia usually formed relatively small and light colored inefficient or ineffective nodules.The effect of these nodules on the accumulation of active components in Glycyrrhiza uralensis should be further studied.In this paper,the root of Glycyrrhiza uralensis was inoculated with rhizobium with low nitrogen fixing efficiency and formed invalid root nodules,so as to further explore the effect of invalid root nodules on active components of Uralcyrrhiza.Liquid chromatoc-mass spectrometry(LC-MS)was used to conduct high-throughput non-targeted metabolomics analysis to determine root tissues of Glycyrrhiza uralensis,and the detected metabolites were analyzed by multivariate analysis method.To explore the effect of ineffective nodules on the accumulation of effective components of Glycyrrhiza uralensis,the metabolites with significant differences were selected,and ultrasonic assisted extraction method was used to optimize the extraction conditions of flavonoids from glycyrrhiza uralensis.The results showed that after inoculation and formation of ineffective root nodules,the growth and development of licorice plants were inhibited.A total of 1171 metabolites were detected in the root tissues of Glycyrrhiza uralensis,and 90 metabolites were screened out,including 28 flavonoids,20 carbohydrates,30 amino acids and 12 organic acids.The metabolism of 12 kinds of flavonoids was upregulated in the root tissues of the Glycyrrhiza uralensis that formed the inactive root nodules,including schaftoside,isoschaftoside,c-hexosyl-apigenin c-pentoside,isovitexin,etc.,and the metabolism of 16 kinds of flavonoids was down-regulated,including glabrene and liquiritigenin.The metabolism of 16 carbohydrate compounds was up-regulated,including nystosa and maltotetraose,and the metabolism of 4carbohydrate compounds was down-regulated,including D-galacturonic acid and maltose.The metabolism of 7 organic acids was up-regulated,including D-ribose-5-phophate and D-myo-inositol-4-monophosohate,and the metabolism of 5 organic acids was down-regulated,including D-threo-isocitric acid and 2-furanoic acid.The metabolism of 17 amino acids was up-regulated,including L-tryptophan and Ldihydroorotic acid,and the metabolism of 13 amino acids was down-regulated,including N-hydroxyl-tryptamine and homoserine.Among them,after the interference of flavonoids by ineffective root nodules,the content of schaftoside increased to 1.53 times of the original,and the content of isoschaftoside increased to 1.74 times of the original,the content of rhoifolin increased to 3.23 times,and the content of 8-omethylretusin increased to 3.08 times.Therefore,inefficient or ineffective rhizobia can also be used to interfere with the anabolic process of active components in Glycyrrhiza uralensis,so as to improve some special medicinal components,such as schaftoside and rhoifolin.Ultrasonic assisted extraction of flavonoids from Glycyrrhiza uralensis,rutin as the standard,HPLC was used to determine the content of flavonoids in the extract,and calculate the extraction rate of flavonoids.On the basis of single factor test,response surface method was used to optimize the ultrasonic extraction process of glycyrrhiza flavone.The optimal extraction conditions were as follows: The material size was 40 mesh,ultrasonic power was 100 w,solid-liquid ratio was 1:15(g/m L),ethanol concentration was 39%,ultrasonic treatment temperature was 59℃,ultrasonic treatment time was 61 min,the flavonoid content was 96.75 μg/g under these conditions.In summary,ineffective root nodules of Glycyrrhiza uralensis will affect plant growth and development,leading to significant differences in the content of metabolites of active components such as flavonoids,sugars,amino acids and organic acids in root tissues,among which the content of flavonoids such as schaftoside and rhoifolin increased significantly.The ultrasonic assisted method can effectively extract flavonoids from Glycyrrhiza uralensis.It laid the foundation for the development and research of licorice functional food.