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佛手多糖的化学组成及体外抗氧化活性研究 总被引:8,自引:0,他引:8
佛手经热水提取和乙醇沉淀,得佛手多糖粗品(BP).BP经Servag法除蛋白,用DEAE离子交换柱梯度洗脱分离得到BP1和BP2两个组分,经凝胶色谱和SDS-聚丙烯酰胺凝胶电泳检验为均一组分.用凝胶渗透色谱法测得BP1和BP2的重均分子量分别为17773和65589.薄层色谱和高效液相色谱分析表明,BP1和BP2均由鼠李糖、甘露糖、葡萄糖、半乳糖和木糖组成.采用化学发光法在多种化学模拟体系中研究了佛手多糖清除活性氧的作用,观察了佛手多糖对HO.导致DNA链损伤的抑制作用.结果表明,佛手多糖能有效地清除O2-.和HO.等活性氧,对DNA链具有良好的保护作用. 相似文献
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合欢皮中两个新八糖苷的分离鉴定和活性研究 总被引:2,自引:0,他引:2
从合欢皮95%乙醇提取物中分离得到2个新的八糖苷(1, 2), 经化学方法与光谱分析将其结构鉴定为3-O-[β-D-吡喃木糖基-(1→2)-α-L-吡喃阿拉伯糖基-(1→6)-β-D-吡喃葡萄糖基]-21-O-[(6S)-2-反式-2-羟甲基-6-甲基-6-O-β-D-吡喃鸡纳糖基-2,7-辛二烯酸基]-金合欢酸-28-O-β-D-吡喃葡萄糖基-(1→3)-[α-L-呋喃阿拉伯糖基-(1→4)]-α-L-吡喃鼠李糖基-
(1→2)-β-D-吡喃葡萄糖基酯(1)和3-O-[β-D-吡喃木糖基-(1→2)-α-L-吡喃阿拉伯糖基-(1→6)-β-D-2-去氧-2-乙酰氨基吡喃葡萄糖基]-21-O-[(6S)-2-反式-2-羟甲基-6-甲基-6-O-β-D-吡喃鸡纳糖基-2,7-辛二烯酸基]-金合欢酸-28-O-β-D-吡喃葡萄糖基-(1→3)-[α-L-呋喃阿拉伯糖基-(1→4)]-α-L-吡喃鼠李糖基-(1→2)-β-D-吡喃葡萄糖基酯(2), 分别命名为合欢皂苷J25 (1, Julibroside J25)和合欢皂苷J22 (2, Julibroside J22). 1和2在体外对4种人癌细胞增殖有明显的抑制作用. 相似文献
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珠兰花香味成份的分离和鉴定 总被引:1,自引:0,他引:1
用石油醚回流蒸馏法抽取新鲜珠兰花的挥发性香味成份,经旋转蒸发器浓缩,通过气相色谱质谱联用仪鉴定出60余种组份,包括脂肪烃,芳香烃,醚,醇,醛酮,羧酸和脂等,主要组分是4-羟基-β-紫罗酮(20%)表茉莉酮酸甲脂(6%)和茉莉酮酸甲脂(4%)。 相似文献
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A new tetradecapeptide, ranamargarin, has been isolated by Sep-Pak C_(18) and HPLC from methanol extracts of the skin of the Chinese frogRana margaratae. The sequence of the peptide is: Asp-Asp-Ala-Ser-Asp-Arg-Ala-Lys-Lys-Phe-Tyr-Gly-Leu-Met-NH_2. This structure has been confirmed by synthesis. The peptide is the largest among the amphibian tachykinins and its N-terminal amino acids are quite different from those of the other tachykinins. The formation of the sulfoxide and peak-splitting of ranamargarin during purification procedures are briefly discussed. 相似文献
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《合成通讯》2013,43(1):155-158
The synthesis of novel LB film materials 2-(4-hexadecyloxyphenylazo)anthraquinone and 2-(4-dodecyloxyphenylazo) anthraquinone is described. These materials were obtained from 2-amino-anthraquinone by azo-coupling with phenol and follwed by Williamson etherification of phenolic hydroxyl group with alkyl bromide. The structures were confirmed by NMR, MS, FT-IR techniques and elemental analysis. 相似文献
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神府煤新法干馏焦油的性质及组成的研究 总被引:6,自引:0,他引:6
本文对神府煤固体热载体新法干馏焦的性质和组成进行了研究。实验结果表明,干馏温度对焦油的产率和性质影响很大,获得焦油的最佳温度为500-550℃。随着干馏温度的增加,焦油的平均分子变大,重组分含量增加。对500℃焦油〈420℃馏分的精细分析结果表明,该馏分主要由酸性组分和中性油组成,碱性组分含量较少。酸性组分主要由苯酚、甲酚和二甲酚组成。中性油主要由脂肪族和芳香族组成,脂肪族中正构烷烃C13-C25 相似文献
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研究了在0.1—2.4MPa条件下三种不同的铁、钴催化剂对Kolbel-Engelhardt反应的催化活性。对于Fe-Co/SiO_2催化剂,在300℃下,CO转化率可从0.1MPa时的64%提高到2.4MPa时的71%,出口气中混合烃的浓度则从1%提高到8.1%,烃产率达160mmol/g-cat·h。烃类产物符合链增长的Schulz-Flory分布,烃类产物中烷烯烃比例及支、直链比例也随压力而变化。实验结果还表明,由一氧化碳歧化引起的结碳现象不严重(<5%)。 相似文献
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将2-甲氧基-5-氯-1,3-亚苯基二甲醛和邻氨基苯酚缩合制得了两种不同熔点和晶型的双Schiff碱C_(21)H_(17)ClN_2O_3(A和B),它们具有相同的UV、IR、NMR及MS。对其中结晶良好的块状单晶B进行了X射线衍射法结构分析。对于2610个1>2σ(I)的独立衍射点,最后偏离因子为R_1(F)=0.044,R_2F=0.057。空间群为P2_1/c。单胞参数:a=10.499(?),b=14.965(?),c=12.178(?),β=108.44°,V=1815(?)~3,Z=4,D_(计算)=1.39g/cm~3。分子呈伸展式结构。 相似文献
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A new neurotensin (NT)-related peptide, margaratensin, was obtained by Sep-Pak C_(18) and RP-HPLC from methanol extracts of the skin of Chinese frog Rana margaratae. The structure of the peptide has been determined to be Asp-Lys-Arg-Pro-Tyr-lle-Leu-His-Glu, which is found to be homologous to the COOH-terminal sequence of NT, but has an extra His-Glu at the COOH-terminus. The synthetic preparation was shown to be indistinguishable from the native peptide during HPLC, amino acid analysis and bioassay. Margaratensin exhibited a hypotensive effect in the rat but the response was weaker than NT. The peptide could induce a potent and reproducible contractile activity on GPI which was different from xenopsin, another NT-related peptide from amphibian skin. 相似文献
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STUDIES ON THE ISOLATION PURIFICATION AND CHARACTERIZATION OF THE FUCOIDAN-GALACTOSAN SULFATE (FGS) FROM LAMINARIA JAPONICA 总被引:3,自引:0,他引:3
TANG Zhihong LI Fuchuan XU Zhongping WANG Hairen** ZHANG Guozhi College of Life Science Shandong University Jinan Yantai Kangtai Medicine Product Corp. Shandong province 《Chinese Journal of Reactive Polymers》2000,(2)
1INTRODUCTIONFGSanditsderivationpossessremarkablemedicinalvalues:antitumouseffect,antiviralactivity,immunomodulation,bloodfatregulation,andhypoglycemia.Studiesonthepolysaccharidefromlaminariajaponicastartedatthebeginningof20thcentury.Thoughalginicacidfromlaminariajaponicahasalreadybeenindustrialized[1],peopledonotknownclearlyaboutlaminarinandfucoidan[2]becauseofrestrictionintheisolationandpurificationmethods[3].Weusedenzymolysistechnique,modernchromatographymethods,andspectralanalysistos… 相似文献