运用反相高效液相色谱(RP-HPLC)对酶解螺蛳腹足肌得到的血管紧张素转换酶(ACE)抑制肽进行两步分离提纯,第一步主要得到8个组分;选取其中活性最高的组分进一步分离,得到2个组分,其中活性较高组分的ACE半抑制浓度为43.5μm o l/L,基本为...运用反相高效液相色谱(RP-HPLC)对酶解螺蛳腹足肌得到的血管紧张素转换酶(ACE)抑制肽进行两步分离提纯,第一步主要得到8个组分;选取其中活性最高的组分进一步分离,得到2个组分,其中活性较高组分的ACE半抑制浓度为43.5μm o l/L,基本为单一肽组分。对提纯的组分分别使用高效液相色谱/电喷雾离子质谱法(HPLC/E S I-M S)和基质辅助激光解吸电离飞行时间质谱法(MALD I-TO F M S)进行分析,同时结合氨基酸组成分析结果,最终得到的肽链一级结构为Lys-G lu-Ile-Trp(KE IW),符合已知的高活性ACE抑制肽的结构规律。经过对两种方法分析过程的比较,认为E S I-M S可以得到多方面的信息,但无法确定肽的序列;MALD I-TO F M S可以得到精确的二级质谱图(m/z精确至0.000 1),从而可以得到确定的肽的序列。展开更多
Chitosans were successfully characterized by matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS). By the use of 2,5-dihydroxybenzoic acid as matrix and second-crystallized method...Chitosans were successfully characterized by matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS). By the use of 2,5-dihydroxybenzoic acid as matrix and second-crystallized method for sample preparation, both the molecular weight and the degradation degrees of acetyl group of chitosan were obtained ,which were valuable for the preparation and quality control of chitosan.展开更多
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used successfully to determine three kinds of bisphthalazinone phenyl ether aromatic polymers with 1,8,9-trihydroxyanthranene as matrix....Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used successfully to determine three kinds of bisphthalazinone phenyl ether aromatic polymers with 1,8,9-trihydroxyanthranene as matrix. The polymerization degree of the polymers were determined to be 1 to 17. The influence of deflection value used in MALDI-TOF MS method was discussed.展开更多
文摘运用反相高效液相色谱(RP-HPLC)对酶解螺蛳腹足肌得到的血管紧张素转换酶(ACE)抑制肽进行两步分离提纯,第一步主要得到8个组分;选取其中活性最高的组分进一步分离,得到2个组分,其中活性较高组分的ACE半抑制浓度为43.5μm o l/L,基本为单一肽组分。对提纯的组分分别使用高效液相色谱/电喷雾离子质谱法(HPLC/E S I-M S)和基质辅助激光解吸电离飞行时间质谱法(MALD I-TO F M S)进行分析,同时结合氨基酸组成分析结果,最终得到的肽链一级结构为Lys-G lu-Ile-Trp(KE IW),符合已知的高活性ACE抑制肽的结构规律。经过对两种方法分析过程的比较,认为E S I-M S可以得到多方面的信息,但无法确定肽的序列;MALD I-TO F M S可以得到精确的二级质谱图(m/z精确至0.000 1),从而可以得到确定的肽的序列。
文摘Chitosans were successfully characterized by matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS). By the use of 2,5-dihydroxybenzoic acid as matrix and second-crystallized method for sample preparation, both the molecular weight and the degradation degrees of acetyl group of chitosan were obtained ,which were valuable for the preparation and quality control of chitosan.
文摘Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used successfully to determine three kinds of bisphthalazinone phenyl ether aromatic polymers with 1,8,9-trihydroxyanthranene as matrix. The polymerization degree of the polymers were determined to be 1 to 17. The influence of deflection value used in MALDI-TOF MS method was discussed.
