Separation And Purification Of Caffeyl Quinic Acid From Stevia

Stevia rebaudinan Betroni is perennial herbaceous plants of Compositae Stevia,is a new sugar source plant,which active component with a high content.The research is mainly on the separation and purification process of total caffeoylquinic acid in stevia with producting the stevioside at the same time.It can not only widen the caffeoylquinic acids(CQA)sources of raw materials,but also to avoid the waste and pollution.It has a good application prospect.The work was carried out to study the separation and purification of stevioside and the total caffeoylquinic acid.(1)The extraction of caffeoylquinic acid in stevia was investigated.Single factor test on the major influencing factors such as extraction solvent concentration,Liquid to material ratio,extraction time was studied.The extractions were as follows:ethanol-water(0-100%,pH3.0-4.0)used as extraction solvent,at 50?,the ratio of solid to liquid 1:20,extraction for 0.5 hour.The caffeoylquinic acid and stevioside completely from the materials extracted.LC-MS was used to identify caffeoylquinic acids in stevia.The results showed that it has six caffeoylquinic acids in stevia.There are 3-O-CQA,4-O-CQA,5-O-CQA,3,5-di-O-CQA,3,4-di-O-CQA,4,5-di-O-CQA.(2)The separation of dicaffeoylquinic acid in stevia was mainly investigated.Dicaffeoylquinic acid,using ethyl acetate extraction 5 times,each time the extraction of 10min.Combined the extraction liquid,steaming to ethyl acetate,the purity of which was 30%was obtained.(3)The extracted dicaffeoylquinic acid were purification by CN206 and CN205 resin.Using pH3.0-4 water,ethanol-water(0-100v/v)as eluent,flow rate of 2 BV/h.The purity of dicaffeoylquinic acid sample was 47.6%and 43.75%.The separation used the polyamide for the second purification.The purity of dicaffeoylquinic acid sample was 72.0%.(4)The separation of monocaffeoylquinic acid and stevioside used NKA-?,CN310 and AB-8 resin.The results showed that CN310 had the highest degree of separation.The monocaffeoylquinic acid concentration was 5.53mg/ml,the stevioside concentration was 90.12mg/ml,the adsorption resin for monocaffeoylquinic acid was 91.7%.The adsorption of stevioside rate was only 5.9%.NKA-? and AB-8 resin can not be good to separate the single monocaffeoylquinic acid and stevioside,it had elution overlapped phenomenon.Resin regeneration after repeated use.(5)The flavonoids and some elements in stevia were detected.The advantages and disadvantages were compared with other plant materials extracted.