Study On The Extraction And Biological Activity Of Ursolic Acid From Hanfu Apple Pomace

Malus(scientific name: Malus Mill.)Is a genus with higher economic value in Rosaceae.Apple is one of the most famous fruits in the world,and China is the country with the highest apple production.The number of "Han Fu" apples planted and processed in Liaoning Province ranks first in the country.In recent years,with the substantial increase in the area of "Han Fu" apples,the processing industry has also developed rapidly.At present,a variety of products such as crisps,fruit vinegar,fruit wine,and fruit juices are on the market.Enterprises produce a large amount of peel and pomace waste during processing.Due to the large production and sales volume of "Han Fu" apples,and the inability to produce additional products,the problems of environmental pollution and waste of resources have been caused.These problems are not consistent with the sustainable development of today’s society Claim.Therefore,in view of the above situation,this paper uses "Han Fu" apple pomace as raw material to extract the highly active component Ursolic Acid in "Han Fu" apple pomace,and adopts the method of dynamic adsorption of macroporous resin to Fruit acid was purified.And because Ursolic Acid is not easily soluble in water,it is not easily absorbed by the human body.Therefore,nano-treatment of Ursolic Acid is beneficial to human body absorption,and the in vitro availability and in vitro activity have been studied.It has laid a theoretical foundation for the in-depth research and development and utilization of Ursolic Acid in the future.The findings are as follows:(1)In this paper,microwave-assisted extraction solvent method was used to extract Ursolic Acid from "Hanfu" apple pomace.The extraction rate was used as the extraction process target.Single factor experiments were performed on the main influencing factors affecting the extraction rate.The single-factor conditions are: extractant liquid concentration,material-liquid ratio,and extraction time.Based on single-factor experiments,the extraction process was optimized by response surface methodology.The optimal extraction process for Ursolic Acid was: extraction time 118 s,material-liquid ratio 1:31,and ethanol concentration fraction of the extractant was Under this condition,the extraction rate of ursolic acid was89.92%,and the extraction amount was 82.57 g / kg.The obtained Ursolic Acid was purified by dynamic resin adsorption.The optimized conditions for the analysis of dynamic resin adsorption were: loading flow rate 4BV / h,loading volume 225 m L,elution flow rate 4BV / h,Pure water is 12 BV.(2)In this paper,β-cyclodextrin-ursolic acid-chitosan nanoparticles were prepared by the emulsifier evaporation method and vacuum freeze-drying method.Β-cyclodextrin is used asthe encapsulating agent and chitosan is used as the stabilizer.This process can reduce the particle size of ursolic acid nanocomposites based on previous studies.Taking drug loading as the characteristics of investigation,the single-factor experimental method was used to screen the preparation process of β-cyclodextrin-ursolic acid-chitosan nanoparticles,and then the orthogonal experimental method was used to test the β-cyclodextrin-bear Fruit acid-chitosan for process optimization.Characterize the ursolic acid nanoparticles with the optimal process,and then observe the physical and chemical properties and structural changes of the ursolic acid nano-embeddings.The optimal conditions obtained by orthogonal experiments are: the ratio of β-cyclodextrin-ursolic acid-chitosan is 1: 5,the homogenization time is 8 min,the homogenization speed is 6000 r.pm,and the number of homogenization times is 4 Times.The drug loading of the ursolic acid nanoparticles prepared under the optimal conditions was19.8% ± 0.45%.The particle size of β-cyclodextrin-ursolic acid-chitosan nanoparticles measured by laser particle size analyzer and zeta potential analyzer was 119.23 ± 7.51 nm,and the potential was 25.96 ± 0.41.The shape of the nanoparticles was observed by scanning electron microscope(SEM).From the observation of scanning electron microscope,it was found that the morphology of the ursolic acid nano-particles was granular.By observing Fourier transform infrared spectroscopy(FT-IR),it can be confirmed that the chemical structure of ursolic acid nanoparticles has not changed.Thermogravimetric differential thermal analysis(TG-DSC)detection can be concluded that ursolic acid nanoparticles have good thermal stability.(3)This article adopts a method of simulating in vitro digestion.By measuring the amount of ursolic acid before and after in vitro digestion,it simulates and compares the absorption of ursolic acid and ursolic acid nanoparticles into the body.And the2,2’-hydrazine-bis(3-ethylbenzothiazole-6-sulfonic acid)diammonium salt radical(ABTS + ·)method was used to determine the antioxidant capacity of ursolic acid,and α-glucoside was used Enzyme inhibitor screening method was used to determine the inhibitory effect of ursolic acid on α-glucosidase and its hypoglycemic activity.It was determined by enzyme kinetic experiments,and then the Lineweaver-Burk diagram was drawn to determine the type of inhibition of α-glucosidase by ursolic acid.The experimental results show that the ursolic acid obtained by the nano-embedding technology has a three-fold improvement in the digestibility of ursolic acid compared to the non-embedded ursolic acid.And played a slow-release role.In terms of antioxidant capacity,the anti-oxidation capacity of ursolic acid after embedding is 3 times higher than that of un-embedded ursolic acid.In terms ofhypoglycemic activity,the inhibition rate of α-glucosidase by the ursolic acid nanoparticles after embedding can reach 88.96%,and the Ic50 value is 94 μM.Compared with the positive drug acarbose,the inhibition rate of α-glucosidase can be comparable.Through enzyme kinetic experiments,it was found that the inhibition type of ursolic acid nano-embedding is competitive inhibition.In order to achieve the development of ursolic acid into health products provides an important theoretical basis.So as to achieve the purpose of preventing and treating diseases such as diabetes and obesity.