Hydrolysis Of Total Saponins Of Ginseng Stem And Leaves And Purification Of Ginsenoside

Ginsenoside is an important active ingredient in ginseng.Among them,protopanaxadiol type and protopanaxatriol type ginsenoside are hydrolyzed to protopanaxadiol and protopanaxatriol during processing and metabolism in vivo,because of the significantly improved bioavailability,they are considered to be the final substance that ginseng exerts pharmacological effects in body.In this paper,the total saponins of ginseng stems and leaves were set as raw materials.Firstly,the hydrolysis process of total saponins of ginseng stems and leaves was screened and optimized to improve the production yield of protopanaxadiol and protopanaxatriol.Then,adopting molecularly imprinted polymer technology to make highly specific adsorption materials,the enrichment and purification process of protopanaxadiol and protopanaxatriol was constructed.The main research results of the paper are as follows:(1)The effects of acid hydrolysis,alkaline hydrolysis and enzymatic hydrolysis on the yield of protopanaxadiol and protopanaxatriol produced by the hydrolysis of total saponins from ginseng stem and leaves were compared,and the hydrolysis process was optimized.The results show that in the acid hydrolysis process,the average yield of protopanaxadiol is 0.21% when the amount of hydrochloric acid is 0.5 m L,the reaction temperature is 90℃,and the reaction time is 4 h;At 4 h,the average yield of protopanaxatriol was 1.84%.In the enzymatic hydrolysis process,when the substrate concentration was 4 mg/m L,60 μL 50 U/m L β-glucosidase concentration was added,the reaction temperature was 70℃,and the reaction time was 8 h,the average yield of protopanaxadiol and protopanaxatriol were 0.07% and 0.15%.In the alkaline hydrolysis process,when the amount of Na OH added was 0.75 g,the reaction temperature was 180°C,and the reaction time was 12 h,the average yields of protopanaxadiol and protopanaxatriol were 2.44% and 10.08%,respectively.Furthermore,a single factor test was designed based on the amount of alkali addition.reaction temperature and reaction time.The best alkaline hydrolysis process conditions were obtained as follows: the amount of Na OH added is 0.75 g,the reaction temperature is 180°C,and the reaction time is 12 h.So,the content of protopanaxatriol and protopanaxadiol are 40.60 ± 0.80 mg/g and 141.89 ± 1.41 mg/g,the average yields are 4.06% and 14.19%,respectively.(2)Using protopanaxadiol and protopanaxatriol as monomolecular and bimolecular templates,respectively,and β-sitosterol as a virtual template to prepare molecularly imprinted polymers using bulk polymerization,and compared the adsorption characteristics of different polymers.The results showed that the saturated adsorption capacity of the protopanaxadiol monomolecular template polymer and the protopanaxatriol monomolecular template polymer to their respective template molecules was 14.82 ± 0.31 mg/g and 12.31 ± 0.44 mg/g,respectively;the saturated adsorption capacity of the bimolecular template imprinting polymer forprotopanaxadiol and protopanaxatriol was 10.70 ± 0.50 mg/g and 11.20 ± 0.24 mg/g,respectively.The saturation adsorption capacity of β-sitosterol virtual template polymer for the protopanaxadiol and protopanaxatriol was 5.11 ± 0.55 mg/g and 6.66 ± 0.38 mg/g,respectively.(3)Solid phase extraction column prepared by using four imprinted polymers as fillers was used for purify protopanaxadiol and protopanaxatriol.The adsorption rates of protopanaxadiol imprinted polymer,protopanaxatriol imprinted polymer,bimolecular templates imprinted polymer and virtual template imprinted polymer to protopanaxadiol and protopanaxatriol was 80.7 ± 2.23% and 40.6 ± 1.36%,82.1 ± 1.54% and 41.2 ± 0.70%,73.7 ± 1.00% and 35.4 ± 1.40%,26.3 ± 1.34% and 10.4 ± 2.10%,respectively.In summary,by comparing the effects of different hydrolysis methods on the conversion from ginseng stems and leaves saponin extracts to protopanaxadiol and protopanaxatriol,the methods with high yields of protopanaxadiol and protopanaxatriol were screened out.The process does not require the addition of organic solvents,which is an environmentally friendly hydrolysis method.By comparing the adsorption effects of molecularly imprinted polymers prepared by different templates on protopanaxadiol and protopanaxatriol,a simple and efficient purification method was constructed.