Study On The Extraction And Purification Of Flavonoids From Garlic And Its Application

Garlic is the underground bulbs of Allium plants,and garlic has been used as condiments in our country.since ancient times.Garlic is rich in many substances that contribute to human health,such as protein,amino acids,vitamins,sulfide,flavonoids and so on.The unique medicinal health function of these chemicals make garlic become a famous edible and medicinal food.Our country has vast territory and abundant resources,and it is the main producing areas of garlic in the world today.China is not only rich in resources,good quality,but also the variety of garlic is more diverse.Output is a quarter of the world's.At present, China is the largest consumer and exporter in the word.The article took garlic as the research object.The major study context in this paper includes those:First of all,the flavonoids were extracted by using two kinds of methods of organic solvent extraction and ultrasonic assisted extraction separately and and select the optimal extraction process.Secondly,the crude flavonoids extracted from garlic was purified by macroporous resin.Taking the static and dynamic adsorption capacity,adsorption rate and desorption rate as the study object and choose the suitable purification conditions of garlic flavonoids.Thirdly,the antioxidant activity of flavonoids in garlic was studied through in vitro antioxidant experiment which includes the determination of O2-· scavenging rate,the determination of ·OH scavenging rate and the determination of DPPH· scavenging rate.Fourthly,using UV Vis Spectrum, infrared spectrum and high performance liquid chromatography to verify the structure and composition of the flavonoids in garlic.Finally, the flavonoids of garlic are used in the beverage process.Based on single factor experiments,the optimum formulation of the compound beverage of garlic flavonoids and green tea was determined by the orthogonal experiment.Based on single factor experiments.the extraction conditions were optimized and determined by response surface methodology.The optimal conditions of organic solvent extraction method are as follows:the ratio of liquid to material was 68:1g/mL.the concentration of ethanol was 56%.water bath time was 3.20h,the water bath temperature was 50?.The extraction amount of flavonoids from garlic was 0.96mg/g.The ultrasound-assisted extraction are as follows:the concentration of ethanol was 58%,the ratio of liquid to material was 45:1g/mL.ultrasonic power was 350W.ultrasonic time was 40min.The extraction amount of flavonoids from garlic was 2.132mg/g.Compared with the organic solvent extraction method,ultrasonic assisted extraction could save more time.more energy, and extract more flavonoids from garlic.Select AB-8 as the adsorbent.The results of static and dynamic adsorption experiments and desorption experiments showed that the suitable purification parameters were obtained by macroporous resin:Initial concentration was 0.05mg/mL,adsorption time was 2h,desorption time was 1.5h,the desorption solution was ethanol solution with pH2.0 concentration of 70%.The volume of the sample was 660mL,adsorption rate was 2BV/h,the eluting volume was 150mL,analytical flow rate was 2BV/h.Compared the antioxidant activity of Flavonoids from garlic with vitamin C,it was concluded that the scavenging rate of*OH and the removal rate of DPPH* were greater than vitamin C and the scavenging rate of garlic flavonoids to O2-# was less than vitamin C.It was concluded that the flavonoids had strong antioxidant activity.There is great value for development.as a natural antioxidant.Analysed and identified the structure and composition of flavonoids in garlic by using ultraviolet spectrum (UV), infrared spectroscopy (IR) and high performance liquid chromatography (HPLC) composition. By ultraviolet absorption spectrum analysis we knew that there are three major absorption peaks in the ultraviolet spectrum of the flavonoids.The 220nm peak showed the extraction containing double bond.The 270nm peak showed the extraction containing benzene ring The 365nm peak showed the extraction containing double bond structure of hetero atom.lt showed that the extraction of garlic had the C6-C3.C6 of flavonoid compounds,which may be the flavonol. Some characteristic absorption peaks of flavonoids were determined by infrared absorption spectroscopy,and to further determine it was flavonoids which was the extraction and purification in the experiment. The extraction and purification of flavonoids from the experiment were analyzed by High performance liquid chromatography.The flavonoids of garlic included five compounds of myricetrin, quercetin, luteolin, kaempferol and apigenin. The content of the quality of the celery was 44.83%..Based on these,The blending process of the compound beverage of garlic flavonoids and green tea was optimized.The sensory evaluation of the beverage was used as the index of investigation,by orthogonal experiment to determine the the five factors of amount of garlic flavonoids,sugar,honey, citric acid and vitamin C effecting the quality of the beverage.At the same time,get the optimal formula:The adding amount of garlic flavonoids was 0.5%,the amount of sugar was 5%,the amount of honey was 0.7%,the amount of citric acid was 0.15% and the vitamin C content was 0.015%.