Separation, Purification And Microbial Transformation Of Cichoric Acid From Pterocarpus Multilobata

Pterocypsela laciniata was an herbaceous plant of Compositae with aboudant resource and great value.It had antioxidant,anti-neoplastic and anti-cardiovascular and cerebrovascular diseases and other functions.However,few scholars researched on it at home and abroad.In this paper,the optimum for extraction,separation and purification,antioxidant activity of cichoric acid-the main component in P.laciniata was carried out.And microbial conversion of cichoric acid extract was investigated.Polyphenol components of P.laciniata extract were identified.Cichoric acid,scutellarin,caftaric acid,chlorogenic acid and 3,5-O-dicaffeoylquinic acid were first identified in this plant by LC-MSn.Furthermore,cichoric acid was recognised as the main component.The polyphenol contents of 20 species plants including P.laciniata were compared.The results showed that the cichoric acid content in P.laciniata was highest(26.1 mg/g),which was 2.2 times higher than Echinacea purpurea(11.8 mg/g),the traditional source for extracting cichoric acid.Moreover,it had an advantage in the biomass.Thus,P.laciniata was a new kind of promising materials for cichoric acid extraction and it was superior to E.purpurea.And it was significant to expand the source of 5 kinds of natural medicine-cichoric acid,scutellarin,caflaric acid,chlorogenic acid and 3,5-O-dicaffeoylquinic acid.The optimum extraction condition of cichoric acid was obtained by single factor experiment and orthogonal test.The extraction efficiency of cichoric acid was ultimately up to 92.57%at the condition of that the raw material was extracted for 70 min at 45 ℃ with 80%ethanol and the so lid-to-liquid ratio of 1:100.The separation and purification process of cichoric acid in the P.laciniata extract was investigated.ADC 201 macroporous resin and polyamide were determined to be suitable separation materials by static adsorption and desorption experiments.The purity of cichoric acid was 49.41%and the recovery was 73.72%after primary purification of ADC 201 macroporous resin.A column packed with polyamide was used to perform a secondary purification.The purity of cichoric acid was reached to 72.03%and the recovery was 81.40%.The antioxidant activities of cichoric acid in P.laciniata were explored.It was shown that the purified cichoric acid was comparabale to Vc with the same concentration in scavenging hydroxyl radical and superoxide radical,which implied cichoric acid was a powerful antioxidant.And the purified cichoric acid(cichoric acid content 72%)was stronger in scavenging DPPH radical,hydroxyl radical and superoxide radical than cichoric acid extract(cichoric acid content 2%),which suggested that the content of cichoric acid was proportional to the scavenging rates of the free radicals.And they were both strongest in scavenging superoxide radical,followed by DPPH radical and hydroxyl radical.Microbial conversion of cichoric acid extract of P.laciniata was carried out.It was indicated that Rhizopus nigricans was an effective microorganism to convert cichoric acid to other valuable products.Cichoric acid was converted 97.3%,whereas caftaric acid was increased by 1.22 times within 77 h.And there were two products-caffeic acid and 3,4-dimethoxycinnamic acid identified,which was increased by 8.34 times and 10.65 times,respectively.Therefore,this work could provide a new approach to prepare caffeic acid,3,4-dimethoxycinnamic acid and caftaric acid.