From the root of Salvia przewalskii Maxim.a new phenolic acid, przewalskinic acid A was isolated and the structure was established by the analysis of^(13)C-NMR,~1H-NMR and two-dimensional COSY experiments.
This study aimed to compare the total phenolic content (TPC) and antioxidant activities of A. rigidula extracts. It also aimed to identify phenolic acids present in the extracts. The 2,2-azinobis-(3-ethylbenzothiazoli...This study aimed to compare the total phenolic content (TPC) and antioxidant activities of A. rigidula extracts. It also aimed to identify phenolic acids present in the extracts. The 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and ferric thiocyanate lipid peroxidation antioxidant assays were performed. High performance liquid chromatography was used to identify phenolic acids. There was no solvent effect on TPC nor on scavenging activities, and inhibition of lipid peroxidation (p > 0.05) among solvent extracts. On the other hand, 1:1:3 water: acetone: methanol extract (10.22 mg GAE/g sample) had significantly higher reducing potential than 50% ethanol extract (EE) (9.259 mg GAE/g sample) (p < 0.05);but EE was not significantly different from 80% methanol extract (9.781 mg GAE/g sample) (p > 0.05). Phenolic fraction designated as fraction 4 had the highest antioxidant activity (p < 0.05) with 69.49% ABTS scavenging activity and FRAP reducing potential, 22.26 mg of GAE/g sample. DPPH scavenging activities of fractions 4 (55.59%) and 5 (55.64%) were significantly higher than the other fractions (p A. rigidula extracts contain gallic, caffeic, vanillic, p-coumaric, salicylic acids and vanillin.展开更多
目的确定实验室超声波提取连翘叶总黄酮、总酚酸的最佳处理条件。方法采用正交设计法对甲醇浓度(A)、超声时间(B)、提取次数(C)和提取温度(D)4个因素进行考察,确定最优超声提取条件。结果因素D和C对测定指标均有显著性影响,因素A、B为...目的确定实验室超声波提取连翘叶总黄酮、总酚酸的最佳处理条件。方法采用正交设计法对甲醇浓度(A)、超声时间(B)、提取次数(C)和提取温度(D)4个因素进行考察,确定最优超声提取条件。结果因素D和C对测定指标均有显著性影响,因素A、B为不显著因素。结论以60%甲醇,超声时间10 m in/次,提取3次,提取温度45℃为最佳超声提取条件。展开更多
文摘From the root of Salvia przewalskii Maxim.a new phenolic acid, przewalskinic acid A was isolated and the structure was established by the analysis of^(13)C-NMR,~1H-NMR and two-dimensional COSY experiments.
文摘This study aimed to compare the total phenolic content (TPC) and antioxidant activities of A. rigidula extracts. It also aimed to identify phenolic acids present in the extracts. The 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and ferric thiocyanate lipid peroxidation antioxidant assays were performed. High performance liquid chromatography was used to identify phenolic acids. There was no solvent effect on TPC nor on scavenging activities, and inhibition of lipid peroxidation (p > 0.05) among solvent extracts. On the other hand, 1:1:3 water: acetone: methanol extract (10.22 mg GAE/g sample) had significantly higher reducing potential than 50% ethanol extract (EE) (9.259 mg GAE/g sample) (p < 0.05);but EE was not significantly different from 80% methanol extract (9.781 mg GAE/g sample) (p > 0.05). Phenolic fraction designated as fraction 4 had the highest antioxidant activity (p < 0.05) with 69.49% ABTS scavenging activity and FRAP reducing potential, 22.26 mg of GAE/g sample. DPPH scavenging activities of fractions 4 (55.59%) and 5 (55.64%) were significantly higher than the other fractions (p A. rigidula extracts contain gallic, caffeic, vanillic, p-coumaric, salicylic acids and vanillin.
文摘目的确定实验室超声波提取连翘叶总黄酮、总酚酸的最佳处理条件。方法采用正交设计法对甲醇浓度(A)、超声时间(B)、提取次数(C)和提取温度(D)4个因素进行考察,确定最优超声提取条件。结果因素D和C对测定指标均有显著性影响,因素A、B为不显著因素。结论以60%甲醇,超声时间10 m in/次,提取3次,提取温度45℃为最佳超声提取条件。