Oligodeoxynucleotide from SARS virus was selected and synthesized. Its complexes with alkaloid compounds were investigated by electrospray mass spectrometry. We found that three alkaloid compounds could interact with ...Oligodeoxynucleotide from SARS virus was selected and synthesized. Its complexes with alkaloid compounds were investigated by electrospray mass spectrometry. We found that three alkaloid compounds could interact with the DNA target molecule in five alkaloids analyzed. With increasing molar ratio of the three alkaloid compounds, the complexes between alkaloids and DNA with different stoichiometric ratios were found in their MS spectra. The order of the alkalinity of their gas phase corresponds to that of liquid phase, that is: Palmatine>Jatrorrhizine>Berberin. The relative abundance of these complexes in mass spectra can assess the relative affinities of above three alkaloid compounds with the DNA target molecule. In this paper, the binding sites between jatrorrhizine and DNA was deduced from the interaction experiments of jatrorrhizine with three nucleosides.展开更多
文摘Oligodeoxynucleotide from SARS virus was selected and synthesized. Its complexes with alkaloid compounds were investigated by electrospray mass spectrometry. We found that three alkaloid compounds could interact with the DNA target molecule in five alkaloids analyzed. With increasing molar ratio of the three alkaloid compounds, the complexes between alkaloids and DNA with different stoichiometric ratios were found in their MS spectra. The order of the alkalinity of their gas phase corresponds to that of liquid phase, that is: Palmatine>Jatrorrhizine>Berberin. The relative abundance of these complexes in mass spectra can assess the relative affinities of above three alkaloid compounds with the DNA target molecule. In this paper, the binding sites between jatrorrhizine and DNA was deduced from the interaction experiments of jatrorrhizine with three nucleosides.
文摘为了改善乳清蛋白可食膜的机械性能,采用干法糖基化改性乳清蛋白,制备乳清蛋白(WPC)-海藻酸钠(SA)共价复合物及其共价复合物膜。分析反应时间、乳化体系的p H值、底物配比(海藻酸钠/乳清蛋白)、相对湿度对WPC-SA共价复合物膜拉伸强度和断裂伸长率的影响;在单因素试验的基础上,采用Box-Behnken设计,对WPC-SA共价复合物膜的拉伸强度进行响应面分析。结果表明,WPC-SA共价复合物膜的最优工艺条件为反应时间60 h,乳化体系p H 8,底物配比3∶1(质量比)。经试验验证,此条件下的拉伸强度为(678.76±0.38)g,与预测值接近。采用十二烷基磺酸钠-聚丙烯酰胺凝胶电泳技术证明WPC和SA发生了共价结合反应;采用傅里叶红外光谱分析也表明乳清蛋白以共价键的结合形式接入了海藻酸钠分子。
