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枸杞子中红色素的提取及稳定性 总被引:10,自引:0,他引:10
枸杞子中红色素的提取及稳定性伍明,王杰,闪春霞,任仲皎,宋锡瑾,詹国庆(中南民族学院化学系武汉430074)关键词枸杞,色素,液泛提取法枸杞子为茄科枸杞属植物的果实,具有补肾养肝,润肺明目以及调节机体免疫力,抑制肿瘤生长和细胞突变,延缓衰老及抗脂肪肝... 相似文献
95.
玉米芯酸提水溶性多糖CCCP的分离纯化和结构研究 总被引:2,自引:0,他引:2
玉米芯用PH=3的HCl煮提得到酸提水溶性粗多糖.该粗多糖组成为Glc,Xyl,Gal,经乙醇分级和Sepharose CL-6B柱层析纯化,得到多糖CCCP.经Sephadex A-25柱层析、比旋光度测定、醋酸纤维薄膜电泳等方法鉴定CCCP为均一多糖.经唾液淀粉酶解、纤维素酶解、部分酸水解、高碘酸氧化、Smith降解、甲基化分析及IR,GC和GC/MS等方法分析表明:CCCP为少分枝结构;主链由吡喃型(1→3)Xyl构成,在O(4)处有分枝;支链主要由(1→4)Glc构成,在O(6)处有分枝,支链还存在1→3,1→6键型连接的Glc,Gal;末端基为Xyl,Glc,Gal. 相似文献
96.
Lingyun Chen Yumin Du Zhigang Tian Liping Sun 《Journal of Polymer Science.Polymer Physics》2005,43(3):296-305
The aggregation behavior of carboxymethyl chitosan (CM‐chitosan) with various degrees of deacetylation (DD) and substitution (DS) was characterized with viscometry, gel permeation chromatography (GPC), and GPC coupled with laser light scattering (GPC‐LLS). The results indicate that CM‐chitosan has a strong tendency to form aggregates in aqueous solution and the aggregation behavior depends on DD and DS values. The apparent aggregation number (Nap), the gyration radius (Rg), and the weight fraction of the aggregates (Fa) reached maximum at a DD value of 50%, then decreased, with the DD value deviating from 50%. A higher DS value helped to form aggregates; when the DS value increased from 0.65 to above 1.0, Nap and Rg increased sharply. The dependence of the refractive index increment (dn/dc) on the DD and DS values was related to variation of the charge density and the hydrophobic interaction along the molecular chains. The conformations of CM‐chitosan aggregates were studied by the LLS method. The aggregates showed a spherical shape, and the chain stiffness increased with introduction of the acetyl groups. The DS value had no clear influence on the chain conformation that was observed. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 296–305, 2005 相似文献
97.
Maria I. Krevvata Nikos Afratis Anastasia Spiliopoulou Christina J. Malavaki Fevronia Kolonitsiou Evangelos Anastassiou Nikos K. Karamanos 《Biomedical chromatography : BMC》2011,25(5):531-534
The extracellular slime of Staphylococcus epidermidis contains, amongst various macromolecules, an acidic polysaccharide (PS) of a molecular mass of 20 kDa with significant antigenic and biological properties. The isolation procedure used so far includes multiple fractionations in anion‐exchange chromatographic columns before its final purification by gel filtration chromatography. This protocol is laborious, time‐consuming and includes the risk of unnecessary loss of PS quantities. Because of the significance of this PS, a modified protocol resulting in an easier and quicker isolation procedure was developed. Furthermore, identification, purity, charge density and molecular integity of the isolated polysaccharide were evaluated by a reverse‐polarity capillary electrophoresis method. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
98.
Yuhao Sun Xiaolin Chen Hong Liu Song Liu Huahua Yu Xueqin Wang Yukun Qin Pengcheng Li 《Molecules (Basel, Switzerland)》2021,26(11)
Avian leukosis virus subgroup J (ALV-J) is an immunosuppressive virus which has caused heavy losses to the poultry breeding industry. Currently, there is no effective medicine to treat this virus. In our previous experiments, the low-molecular-weight Sargassum fusiforme polysaccharide (SFP) was proven to possess antiviral activity against ALV-J, but its function was limited to the virus adsorption stage. In order to improve the antiviral activity of the SFP, in this study, three new SFP long-chain alkyl group nanomicelles (SFP-C12M, SFP-C14M and SFP-C16M) were prepared. The nanomicelles were characterized according to their physical and chemical properties. The nanomicelles were characterized by particle size, zeta potential, polydispersity index, critical micelle concentration and morphology. The results showed the particle sizes of the three nanomicelles were all approximately 200 nm and SFP-C14M and SFP-C16M were more stable than SFP-C12M. The newly prepared nanomicelles exhibited a better anti-ALV-J activity than the SFP, with SFP-C16M exhibiting the best antiviral effects in both the virus adsorption stage and the replication stage. The results of the giant unilamellar vesicle exposure experiment demonstrated that the new virucidal effect of the nanomicelles might be caused by damage to the phospholipid membrane of ALV-J. This study provides a potential idea for ALV-J prevention and development of other antiviral drugs. 相似文献
99.
Embedding magnetic nanoparticles into polysaccharide-based hydrogels for magnetically assisted bioseparation. 总被引:1,自引:0,他引:1
Based on the preparation of biocompatible polysaccharide-based hydrogels with stimuli-responsive properties by the copolymerization of maleilated carboxymethyl chitosan with N-isopropylacrylamide, novel magnetic hybrid hydrogels were fabricated by the in situ embedding of magnetic iron oxide nanoparticles into the porous hydrogel networks. Scanning electron microscopy (SEM) and thermogravimetric (TG) analyses showed that the size, morphology, and content of the iron oxide nanoparticles formed could be modulated by controlling the amount of maleilated carboxymethyl chitosan. As confirmed by X-ray diffractometry (XRD), equilibrium swelling ratio, and differential scanning calorimetry (DSC) measurements, the embedding process did not induce a phase change of the magnetic iron oxide nanoparticles, and the resultant hybrid hydrogels could retain the pH- and temperature-responsive characteristics of their hydrogel precursors. By investigating the partition coefficients of bovine serum albumin as a model protein, this magnetic hydrogel material was found to hold a potential application in magnetically assisted bioseparation. 相似文献
100.
A polysaccharide named PNP was extracted and purified from Pholiota nameko. The total sugar content of PNP was 95.29% and the molecular weight was 1.89 × 103 kDa. The structural features of PNP were investigated by the combination of chemical and instrumental analysis such as UV spectrophotometer, specific rotation determination, FT-IR, methylisation analysis and Congo red. The results showed that the optical rotation of PNP was +120° and that it had a triple-helical structure. Besides, PNP was mainly composed of glucose and mannose at the molar ratio of 4.24:1.00. The backbone of PNP was composed of (1→3)-linked-Glc and (1→3)-linked-Man whereas the branches of (1→3,6)-linked- Glc, (1→3,6)-linked-Man and T- Glc. Consistenting with the results of UV–Vis spectra, FT-IR spectroscopy and 1H NMR, indicated that PNP was a complex of polysaccharides and polyphenols. In vitro antioxidant results suggested that PNP was processed with certain scavenging capacity. 相似文献