Study On The Separation And Antioxidant Activity Of Dihydrogenistein From Polygonatum Odoratum

Polygonatun odoratum(POM)belongs to the Liliaceae,it was confirmed to be medicine and food raw materials by the State Health Development Planning Commission.POM contains the natural homoisoflavone,which has the function of antioxidant and anticancer.Take the power of POM as raw material,the operational approach of extracting homoisoflavone with eutectic mixture and depuration the homoisoflavone by HSCCC,apply the high performance liquid chromatography(HPLC)to separate the homoisoflavone,and identify the structure of homoisoflavone through spectroscopy.At end,the mechanism of antioxidant activity was discussed.The main conclusions were as follows:1.The eutectic solvent extract POM flavonoids,composition and ratio of eutectic solvent in extraction process,material liquid ratio,water content of extract,extraction temperature,extraction time and so on were studied,the best extraction process of POM flavonoids determined by single factor test and response surface analysis.Resu Lts show,choline chloride and ethylene glycol were used as the most suitable eutectic solvent by 1:1 ratio,the most suitable material liquid ratio was 1:15,the water content of the extract was 70%,the extraction temperature was 45?,extraction time was 60 min,under this condition,the extraction rate of flavonoids from POM was 0.615%.2.The optimal conditions for purification of POM flavonoids by HSCCC were as follows: trichloromethane methanol water(8:10:5)as solvent system,mobile phase flow rate of 3 m L / min,HSCCC column temperature of 25 ?,detection wavelength of 290 nm,single injection volume of 20 m L.According to this condition,a large number of impurities can be effectively removed from the flavonoid extract of POM,the purity of flavone can be improved(63.3%),and the operation time and reagent dosage can be significantly saved.3.Use U3000 preparative high performance liquid chromatography to separate the flavonoids from POM,the best condition were detection wavelength of 296 nm,the mobile phase of methanol-water(58:42),the suitable concentration of methanol when the sample taken in was 40%,the total flow rate was 3m L/min,column temperature of 20?,sample size was 200?L,the appropriate delay time for collecting adjacent target components is 4-8s.The five kinds of homoisoflavone were 5,7,6'-three hydroxyl-6,8-two methyl-4'-methoxydimethylchroman-4-one(PDCO-1)?5,7,4'-three hydroxyl-6,8-two methyl-dimethylchroman-4-one(PDCO-2)?5,7,4'-three hydroxyl-6-methyl-8-methoxy-dimethylchroman-4-one(PDCO-3)?5,7,4'-three hydroxyl-6-methyl-dimethylchroman-4-one(PDCO-4)?5,7-dihydroxy-6-methyl-8,4'-dimethoxy-dimethylchroman-4-one(PDCO-5).The purity of the flavone was high,which can meet the requirements of biological activity analysis and research.4.The five kinds of POM homoisoflavone were studied with monomer composition in vitro and zebrafish embryo in vivo antioxidant,we found the five kinds of POM homoisoflavone had good antioxidant ability.Compared with PDCO-1 and PDCO-5,PDCO-2,PDCO-3 and PDCO-4 had obvious advantages in antioxidant capacity.The antioxidant capacity of PDCO-4 was stronger than that of VC with the same concentration.In general,the relationship between the antioxidant capacity of the five isoflavones was PDCO-4 > PDCO-2 > PDCO-3 > PDCO-1 > PDCO-5.5.The difference of antioxidant activity of dihydrogenistein in POM was due to the influence of 4' position in the molecu Le on the position and quantity of active hydroxyl and oxymethyl.The antioxidant activity of high isoflavones with active hydroxyl group at 4' position was higher than that without hydroxyl group.The antioxidant activity of those with oxymethyl group was weak.Meanwhile,the position and quantity of oxymethyl group also had some influence on the antioxidant activity.6.After different processing,the antioxidant activity of total flavonoids in POM was decreased,the sample after yeast fermentation was decreased least,and the sample after extrusion and expansion were decreased most.The relationship between the antioxidant activities of the five processed POM flavonoids was as follows: the antioxidant activities of POM flavonoids after yeast fermentation,the antioxidant activities of POM flavonoids after lactic acid fermentation,the antioxidant activities of POM flavonoids after baking,the antioxidant activities of POM flavonoids after high pressure treatment,and the antioxidant activities of POM flavonoids after extrusion.In the process of food processing,baking,extrusion and high-pressure treatment shou Ld be avoided,and yeast fermentation shou Ld be carried out before food processing.7.The reason for the change of the antioxidant activity of the total flavonoids in POM after different processing was that the contents of PDCO-4,PDCO-2 and PDCO-3 decrease after baking treatment,and the contents of five dihydrohyperisoflavones decrease after extrusion and expansion treatment.The total amount of flavonoids decreased and the content of PDCO-1 increased after lactic acid fermentation.After high pressure treatment,the contents of PDCO-4,PDCO-2 and PDCO-3 decreased,while the contents of PDCO-5 increased relatively.After yeast fermentation,the content of PDCO-3 and PDCO-4 increased,the content of PDCO-1 and p PDCO-5 decreased,and the content of total flavonoids decreased slightly.The research resu Lts can provide convenience for related personnel to fu Lly understand the resources and separate the functional components of POM,and provide reference for POM processing enterprises to develop new products and improve its functional characteristics.