Study On Enzymatic Hydrolysis Of Taraxacum Mongolicum Hand.-Mazz Peptide

T.mongolicum has the medicinal effects of clearing away heat and detoxifying,reducing swelling and dispersing,diuresis cholagogue,and eliminating inflammation and dispersing.Modern pharmacological studies have shown that T.mongolicum has the effects of anti-fungal,anti-inflammatory,anti-oxidation,anti-tumor,immune regulation and Etc.The main active ingredients are flavonoids,polysaccharides,proteins and so on.To expand the T.mongolicum protein peptide in antibacterial peptide,antioxidant peptide drug and health food development in the field of application of vacancies on the T.mongolicum oligopeptide research direction,this topic with T.mongolicum root as a raw material for the whole activity analysis,protein extraction technology,enzyme peptide and protein components of different molecular weight active analysis,enzyme hydrolysis,LC-MS analysis several aspects are studied,the specific results are as follows:In this paper,the dry root of T.mongolicum was used as the research object.The system was used to screen the different polar components of T.mongolicum.The antibacterial method was used to investigate the different polar components against Escherichia coli,Staphylococcus aureus and Bacillus subtilis.At the same time,the antioxidant activities of the components with different polarity were investigated by hydroxyl radical scavenging rate.The results showed that the water layer had a significant effect on the activity of Escherichia coli and Staphylococcus aureus,and the water layer was slightly stronger than other components,and each component had no inhibitory effect on Bacillus subtilis.The antioxidant activities of the ethanol layer and the water layer were 63.14%and 61.21%,respectively.The T.mongolicum root protein was extracted with water by extraction temperature,extraction time and extraction ratio.The orthogonal experiment was established on the basis of single factor experiment and the optimal process parameters were obtained.The extraction time was 120 min and the extraction temperature was 30°C.The extraction ratio was 1:30.It has been proved by experiments that the protein content of the aqueous extract under this condition is 13.88%.Ultrafiltration grading of T.mongolicum water extract using ultrafiltration technology.Using 1KDa,3KDa,10KDa ultrafiltration membrane,the T.mongolicum protein in the extract is classified into four groups,namely more than 10KDa,3-10KDa,1-3KDa,less than 1KDa components.After enzymatic hydrolysis of more than 10KDa component,the enzymatic hydrolysis solution was passed through the 1KDa ultrafiltration membrane to obtain the enzymatic oligopeptide fraction.The comparative experiment of the antibacterial activity and antioxidant activity of each component showed that the components were against Escherichia coli.And Staphylococcus aureus inhibitory activity sequence is enzymatic oligopeptide>less than 1 KDa>1-3 KDa>3-10 KDa>greater than 10 KDa>blank control,enzymatic oligopeptide fraction,less than 1 KDa component sample The bacterial circle was significant?P<0.05?,and the sequence of hydroxyl radical scavenging was enzymatic oligopeptide>less than 1 KDa>3-10 KDa>1-3 KDa>greater than 10 KDa.Considering that T.mongolicum was less than1KDa component oligopeptide content,and total extract and protein content greater than 10KDa is relatively more,so the subject used enzymatic hydrolysis to prepare enzymatic peptides and screen out the optimal enzymatic hydrolysis process,with the enzymatic hydrolysis temperature,enzyme bottom ratio,pH value,and time as the basic factors.On the basis of single factor experiment,the optimal enzymatic hydrolysis parameters were obtained by response surface methodology:enzymatic hydrolysis temperature 37°C,enzymatic hydrolysis time 4 h,pH value1.8.The enzyme bottom ratio was 5%,the predicted polypeptide response was 6.68%,and the predicted hydrolysis response was 47.09%.The degree of influence of the four enzymatic factors on the enzymatic hydrolysis effect was selected as follows:temperature>enzyme bottom ratio>pH value>time.Further determination of the active constituents of T.mongolicum aqueous extracts,separation and purification of T.mongolicum natural oligopeptides using a gel column,identification of amino acid-containing fractions by thin layer chromatography,combined with liquid chromatography-mass spectrometry for T.mongolicum natural oligopeptides and enzymes The structure of the oligopeptide was analyzed and six oligopeptides were analyzed.It was speculated that the structure of the natural oligopeptide may be:the structure of the oligopeptide PGYGT-T1 was NH₂-Asp-Val-COOH,and the structure of the oligopeptide PGYGT-T2 was NH₂-Asn-Glu-COOH,the structure of the oligopeptide PGYGT-T3 was NH₂-Val-Arg-COOH.The enzymatic oligopeptide structure may be:the structure of the oligopeptide PGYGT-M1 was NH₂-PHe-Lys-COOH or NH₂-PHe-Gln-COOH,and the structure of PGYGT-M2 was NH₂-His-Cys-COOH,PGYGT-M3 The structure is NH₂-Val-Arg-COOH.