Research Of Anthocyanins And Polysaccharides In Platycodon Grandiflorum

In China, Platycodon Grandiflorum have long been used as traditional foods and medicines. The Platycodon Grandiflorum contains an abundance of resources that possess a multitude of biological activities, such as the anthocyanins, polysaccharides and saponins, thus the study is valuable for economic benefit and social value. Anthocyanins in Platycodon Grandiflorum (platyconins) and polysaccharides in Platycodon Grandiflorum (PGPs) were studied in this paper. The extraction process, purification process, stability and anti-free radical capacity in vitro of platyconins were studied, while the isolated process, purified process and its basic nature were also determined.Firstly, microwave-assisted extraction(MAE) was identified to be best way to extract platyconins by optimization experiment and observed with the scanning electron microscopy (SEM). The results showed that the highest extraction rate of polysaccharides was reached 93.2% at the microwave power 400W, extraction time 91.0s and ratio of liquid to solid 24.5mL·g-1. Meanwhile, HPD700, a kind of macroporous resin was selected to purify the platyconins whose color value could be increased by 8.2-fold.Secondly, the stability of platyconins was studied. The results showed that platyconins were stable in the most conditions, and food addiitive, ascorbic acid and sucrose had less effect on the stability of platyconins. The platyconins was instability in alkalescence and oxidant circumstances. Moreover, Fe3+ and Al3+can affect the stability of platyconins. Also the results showed that the anti-free radical capacity for platyconins in vitro were powerful. And the ability of anti-free radicals in vitro depends on the concentration of platyconins.Finally, three single-compoent polysaccharides PGPsⅠ, PGPsⅡand PGPsⅢwere obtained after hot water extraction, alcohol precipitation and DEAE-cellulose chromatography experiments. The three single-compoent polysaccharides don't contain nucleic acid, protein and starch by the purity test. And the molecular weight of PGPsⅠ, PGPsⅡand PGPsⅢwere respectively 2640,89759 and 63453, respectively. The infrared spectroscopy analysis was used to confirm the structure of PGPsⅠ, PGPsⅡand PGPsⅢ. The results showed that PGPs I contained furan glycosidic bond and PGPs II containedβ-pyran-glycosidic bond, while the PGPsIII had furan-glycosidic-bond and D-pyran-glycosidic bond. By the atomic force microscope observing, the polysaccharide molecules had clear spiral structure, and presented in a certain concertration of the different dispersion.