Two new β-hydroxy amino acid-coupled secoiridoids, named serinosecologanin （1） and threoninose- cologanin （2）, were isolated from an aqueous extract of the flower buds of Lonicera japonica. Their uncommon structu...Two new β-hydroxy amino acid-coupled secoiridoids, named serinosecologanin （1） and threoninose- cologanin （2）, were isolated from an aqueous extract of the flower buds of Lonicera japonica. Their uncommon structures including absolute configurations were determined by spectroscopic data analysis, and confirmed by semisynthesis from the co-occurring secologanin （3） and secologanic acid （4）. Compounds 1 and 2 exhibited resistant activity against β-glucosidase from almonds and hesperidinase from Aspergillus niger, they also showed activity against the release of glucuronidase in rat polymorphonuclear leukocytes induced by the platelet-activating factor with inhibition rates of （34.9 ±3.1 ）% and （53.6 ± 2.6）%, respectively.展开更多
The aims of this study were to investigate the effect of precise phosphorylation of Ser in GL-Hyp-GPSGEEGKR on its Fe^(2+)chelating capacity,and the effects and mechanisms of folic acid coupling to GL-Hyp-GPS_((PO4))G...The aims of this study were to investigate the effect of precise phosphorylation of Ser in GL-Hyp-GPSGEEGKR on its Fe^(2+)chelating capacity,and the effects and mechanisms of folic acid coupling to GL-Hyp-GPS_((PO4))GEEGKR on its resistance against degradation by gastrointestinal enzymes.The results demonstrated that GL-Hyp-GPS_((PO4))GEEGKR exhibited significantly enhanced Fe^(2+)chelating capability compared to GL-Hyp-GPSGEEGKR.This was attributed to the phosphorylation of Ser introducing more Fe^(2+)chelating sites.Furthermore,the results of UV-Vis,FTIR,and ^(1)H NMR showed that folic acid has successfully coupled with GL-Hyp-GPS_((PO4))GEEGKR to generate folic acid-GL-Hyp-GPS_((PO4))GEEGKR.Folic acid-GL-Hyp-GPS_((PO4))GEEGKR demonstrated superior resistance against degradation by gastrointestinal enzymes.This may be attributed to the coupling of folic acid altering the original zeta potential of the peptide and the steric hindrance effect of folic acid hindering the interaction between enzymes and peptide.These findings can provide valuable insights for the production of high Fe^(2+)chelating peptides that resist gastrointestinal enzyme degradation.展开更多
基金Financial support from the National Natural Science Foundation of China (NNSFC Nos.20772156 and 30825044)+1 种基金the Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT,No.IRT1007)the National Science and Technology Project of China (Nos.2012ZX09301002-002 and 2011ZX0 9307002-01)
文摘Two new β-hydroxy amino acid-coupled secoiridoids, named serinosecologanin （1） and threoninose- cologanin （2）, were isolated from an aqueous extract of the flower buds of Lonicera japonica. Their uncommon structures including absolute configurations were determined by spectroscopic data analysis, and confirmed by semisynthesis from the co-occurring secologanin （3） and secologanic acid （4）. Compounds 1 and 2 exhibited resistant activity against β-glucosidase from almonds and hesperidinase from Aspergillus niger, they also showed activity against the release of glucuronidase in rat polymorphonuclear leukocytes induced by the platelet-activating factor with inhibition rates of （34.9 ±3.1 ）% and （53.6 ± 2.6）%, respectively.
基金the financial support from the National Key R&D Program of China(2022YFD2100905)the earmarked fund for CARS(CARS-46)+2 种基金the National Natural Science Foundation of China(32372250)the Hainan Provincial Natural Science Foundation(323MS12)the Central Public-interest Scientific Institution Basal Research Fund,CAFS(2023TD74).
文摘The aims of this study were to investigate the effect of precise phosphorylation of Ser in GL-Hyp-GPSGEEGKR on its Fe^(2+)chelating capacity,and the effects and mechanisms of folic acid coupling to GL-Hyp-GPS_((PO4))GEEGKR on its resistance against degradation by gastrointestinal enzymes.The results demonstrated that GL-Hyp-GPS_((PO4))GEEGKR exhibited significantly enhanced Fe^(2+)chelating capability compared to GL-Hyp-GPSGEEGKR.This was attributed to the phosphorylation of Ser introducing more Fe^(2+)chelating sites.Furthermore,the results of UV-Vis,FTIR,and ^(1)H NMR showed that folic acid has successfully coupled with GL-Hyp-GPS_((PO4))GEEGKR to generate folic acid-GL-Hyp-GPS_((PO4))GEEGKR.Folic acid-GL-Hyp-GPS_((PO4))GEEGKR demonstrated superior resistance against degradation by gastrointestinal enzymes.This may be attributed to the coupling of folic acid altering the original zeta potential of the peptide and the steric hindrance effect of folic acid hindering the interaction between enzymes and peptide.These findings can provide valuable insights for the production of high Fe^(2+)chelating peptides that resist gastrointestinal enzyme degradation.
