| Pomegranate has been recognized as a verstaile nurtaceutical species with great economic and environmental potential in China,which is wideiy cultivated with an increasing production in recent ysars. Pomegranate can be divided into three parts, pomegranate peel, seed and septum, each several part are 55%,40%和5% respectively. Pomegranate seed include pulp, seed-case and kernel, pomegranate pulp 62%, pomegranate seed-case 35%, and kernel 3%. The weight of pomegranate kernels is about 25% of pomegranate seed. The main application of pomegranate seed is to extract oil. While the rest be researched lessly, in which has a lot of proanthocyanids. Poranthocyandins displays various types of physiological function including antioxidant activity, anti-tumor activity and anti-hypertensive activity. In this paper pomegranate planted in Lintong of Shanxi province was took as experimental material. This paper studied the technology for extracting proanthocyanids from pomegranate seed, extraction technology from pomegranate seed with chelon and the effect of chelon to proanthocyanids stability, the different technical methods of extraction, separation, purification of proanthocyanids and its antioxidant activity were studied. Proanthocyanids of pomegranate seed were purified by macroporous resin and Sephadex LH-20. Moreover, in the last chapters, the purity and structure of proanthocyanids were analyzed by means of UV spetrum, IR spetrum, high performance liquid chromatography, ESI-MS and other technologies. The main results were as follows:(1) The yield can be raised with chelon to extract pomegranate phenol and proanthocyanids from pomegranate seed. The effect of SH to proanthocyanids with ions, such as Fe2+, Sn2+, Pb2+, Mg2+, Cu2+, Zn2+, was studied. The results show the contents of proanthocyanids improving 8.00%, 13.97%,57.37%,25.59%,59.29%,34.50%,contrast with control. The effect of SH to Fe2+ is the worst, to Cu2+, Pb2+is obvious. Extracting phenol and proanthocyanids from pomegranate seed can be promoted with SH obviously.(2) Evaluation of vanillin assay proved that it has good repeatability and high recovery, and is also more sensitive and stable compared with normal butanol method. Proanthocyanids of pomegranate seeds can be quantified and compared by this method. Results showed that the proanthocyanids content of pomegranate seed was affected by storeage time. Proanthocyanids should be extracted from pomegranate seeds in short storage time. And the proanthocyanids content of pomegranate seed was affected by extracting times too, it shows we can obtain 85.4% proanthocyanids from pomegranate seed by extracted three times, obtain 97.2% by extracted four times.(3) The extraction technology of proanthocyanids in pomegranate seed was optimized by quadric regression orthogonal rotary tests. The mathematics formula was: Y= 7.496+ 0.0797X1+ 0.2203X2+ 0.2111X3- 0.2345X12+ 0.05722X22- 0.00465X32+ 0.2838X1X2+ 0.0613X1X3- 0.3138X2X3, the optimum parameters of extraction were: ethanol concentration 60%, time 87min, SH concentration 0.13%, which content is 8.58%.(4) Molecular composition and its construction unit of proanthocyanids from pomegranate seed after purification were characterized by UV spetrum, FT-IR spectroscopy, and electron paramagnetic resonance (EPR). The results show that aliphatic admixtures were removed by washing with organic solvents, and the saccharide and solubility saline content was reduced by macroporous resin, other phenolic compound was removed by Sephadex LH-20. HPLC- MS was used to purify and identify the proanthocyanids of pomegranate seed. The primary construction unit of proanthocyanids of pomegranate seed is cyanidin.(5) Among these antioxidation indices, besides scavenging rate of DPPH? and reducing power and scavenging rate of ?OH show significant correlation both, there is no significant correlation each other. Proanthocyanids of pomegranate seed shows good antioxidant activity. Reducing power and scavenging rate of ?OH, O2-?, DPPH? of PSP increase with the increase of the concentration, and there are significant dose-effect relationship between them. The IC50 of ?OH, O2-?, DPPH? are 11.10μg/L, 26.78μg/mL, 102.32μg/L. PSP could also enhance the activity of GSH-Px, inhibit the production of MAD and hemolytic of red blood cell in mice, and the inhibition increase with the increase of the concentration.(6) The stability of proanthocyanidins of pomegranate seed was studied in the simulate food systems. The results showed that proanthocyanidins of pomegranate seed were likely stable at low temperature. Among different metallic ions, Sn2+,Fe2+ and Cu2+ have significant influence on the stability of proanthocyanidins,adding SH makes it more stable. The amount would dcrease under the sun light,VC and NaHSO3 could improve the stability of proanthocyanidins, and their effects were related to their concentrations. Furthermoer, proanthocyanidins of pomegranate seed could be protected by sugars and common salt, the order of protect effect was: fructose> glucose > common salt > sucrose. The degradation of proanthocyanids of pomegranate seed is followed first-order reaction kinetics, and the thermal degradation activation energy of proanthocyanids of pomegranate seed is 35.29 kJ/mol, and the rate constant (k0) is 4682.6. The theoretical value and experimental value are propinquity, which indicate that the model is appropriate. |
PDF Full Text Request