FOOD CHEMISTRY
·
2020
·
IF 6.306
Dingmin Zhang,Xiaoyun Jiang,Liubang Xiao,Yongling Lu,Shengmin Sang,Lishuang Lv,Wenjiang Dong
Acrolein (ACR) is an unsaturated aldehyde with high activity and toxicity and is produced in vivo and in food. This study investigated the impact of B-ring structure on the trapping of ACR by flavonols and the trapping mechanism and efficacy of ACR by myricetin. Galangin, kaempferol, quercetin, and myricetin, which possess the same A- and C-ring but different numbers of –OH groups on the B-ring, were selected for this study. Our results suggested that increasing the number of –OH groups on the B-ring can enhance the ACR trapping efficacy of flavonol and myrectin was identified as the most active flavonol. The adducts of myricetin with ACR under different ratios and incubation times were analyzed using LC-MS/MS. We also purified and identified the major mono- and di-ACR-myricetin adducts. Furthermore, myricetin could dose-dependently inhibit the formation of ACR in cookies through the formation of mono- and di-ACR adducts.
研究领域:
食品科学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2023
·
IF 3.8
Xiangrong Li,Ruonan Xu,Tianjun Ni
Flavonols are studied extensively because of their interesting biological activities. Galangin, kaempferol, quercetin, and myricetin are structurally related flavonols that differ only in the number of B-ring hydroxyl substituents. In this work, we have carried out a detailed study on the interaction of these structurally related flavonols and γ-globulin/fibrinogen/trypsin/pepsin by using experimental as well as molecular docking approaches. Studies show that the flavonol-protein complex is formed after the interaction of flavonols with the four proteins, which has moderate quenching and binding ability. The effects of the number and position of the hydroxyl groups in flavonols B-ring on the quenching constant, binding constant, number of binding sites, thermodynamic parameters as well as the changes of the secondary structure of proteins are elucidated. The interaction between flavonols and γ-globulin/fibrinogen/trypsin/pepsin is a spontaneous exothermic process driven by enthalpy and entropy, and the main force types are hydrophobic and hydrogen bonds. For some systems, electrostatic forces are also involved. The interaction of flavonols with the four proteins results in loosening and unfolding of backbone of proteins. Moreover, galangin and quercetin also reduce the hydrophobicity of the tryptophan (Trp) microenvironment. The secondary structure of γ-globulin/fibrinogen/trypsin is affected by the number of hydroxyl groups on the B-ring. Except that myricetin does not bind to the catalytic active center of pepsin and seems to have no inhibitory effect on the activity of pepsin, for other flavonol-fibrinogen/trypsin/pepsin systems, flavonols are bound to the active center of the three proteins, and have certain influence on the activity of them.
研究领域:
生物化学
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药理学
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产品关联
DOI
高影响因子
MOLECULES
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2018
·Vol. 23
·期 12
·3083
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IF 3.098
Xiaojian Ouyang,Xican Li,Wenbiao Lu,Xiaojun Zhao,Dongfeng Chen
To clarify the role of theB-ring in antioxidant flavonols, we performed a comparative study between galangin with a nullB-ring and 3,5,7-trihydroxychromone without aB-ring using five spectrophotometric assays, namely,•O2−-scavenging, 1,1-diphenyl-2-picrylhydrazyl radical (DPPH•)-scavenging, 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide radical-scavenging, 2,2′-azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid) radical-scavenging, and Fe3+-reducing activity. The DPPH•-scavenging reaction products of these assays were further analyzed by ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UPLC-ESI-Q-TOF-MS/MS) technology. In the five spectrophotometric assays, galangin and 3,5,7-trihydroxychromone dose-dependently increased their radical-scavenging (or Fe3+-reducing) percentages. However, galangin always gave lower IC50values than those of 3,5,7-trihydroxychromone. In the UPLC-ESI-Q-TOF-MS/MS analysis, galangin yielded galangin-DPPH adduct MS peaks (m/z662, 434, 301, 227,196, and 151) and galangin-galangin dimer MS peaks (m/z538, 385, 268, 239, 211, 195, and 151). 3,5,7-Trihydroxychromone, however, only generatedm/z3,5,7-trihydroxychromone-DPPH adduct MS peaks (m/z586, 539, 227, 196, and 136). In conclusion, both galangin and 3,5,7-trihydroxychromone could similarly undergo multiple antioxidant pathways, including redox-dependent pathways (such as electron transfer (ET) and ETplusproton transfer (PT)) and a non-redox-dependent radical adduct formation (RAF) pathway; thus, the nullB-ring could hardly change their antioxidant pathways. However, it did improve their antioxidant levels in these pathways. Such improvement of theB-ring toward an antioxidant flavonol is associated with its π-π conjugation, which can provide more resonance forms and bonding sites.Keywords:antioxidant;galangin;3,5,7-trihydroxychromone;flavonol;structure–activity;B-ring
研究领域:
生物化学
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药理学
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Haolin Zhang,Shiye Lin,Ruiwei Xie,Weizhi Zhong,Hui Wang,Mohamed A. Farag,Hidayat Hussain,Randolph R.J. Arroo,Xiaojia Chen,Jianbo Xiao
In the field of thermal degradation of flavonoids, current studies mainly focused on flavonols. However, the thermal degradation of dihydroflavonols in aqueous solution has received limited attention compared to flavonols. The single C2-C3 bonds of dihydroflavonols, which differs from the C2-C3 double bond in flavonols, may cause different degradation mechanisms. Dihydromyricetin (DMY) is a typical dihydroflavonol with six hydroxyl groups, and possesses various health effects. We explored the thermal degradation of DMY in neutral aqueous solution (pH 7) at 100 ℃. Ultra-performance liquid chromatography combined with photodiode array and electrospray ionization quadrupole-time-of-flight tandem mass spectrometric detection (UPLC-PDA-ESI-QTOF–MS/MS) provided suitable platform for exploring DMY degradation pathways, and negative ion mode was applied. Thermal treatment led to a decline in DMY level with time, accompanied by the appearance of various degradation products of DMY. Degradation mechanisms of DMY included isomerization, oxidation, hydroxylation, dimerization and ring cleavage. The pyrogallol-type ring B of DMY might be initially oxidized into ortho -quinone, which could further attack another DMY to form dimers. In addition, hydroxylation is likely to occur at C-2, C-3 of DMY or DMY dimers, which then further yields ring-cleavage products via breakage of the O1-C2 bond, C2-C3 bond, or C3-C4 bond. The 3-hydroxy-5-(3,3,5,7-tetrahydroxy-4-oxochroman-2-yl) cyclohexa-3,5-diene-1, 2-dione ( m / z 333.0244) and unknown compound m / z 435.0925 were annotated as key intermediates in DMY degradation. Four phenolic acids, including 3,4,5-trihydroxybenzoic acid ( m / z 169.0136, RT 1.4 min), 2,4,6-trihydroxyphenylglyoxylic acid ( m / z 197.0084, RT 1.7 min), 2-oxo-2-(2,4,6-trihydroxyphenyl) acetaldehyde ( m / z 181.0132, RT 2.4 min), and 2,4,6-trihydroxybenzoic acid ( m / z 169.0139, RT 2.5 min) were identified as the major end products of DMY degradation. In addition, 5-((3,5dihydroxyphenoxy) methyl)-3-hydroxycyclohexa-3,5-diene-1,2-dione (m / z 261.0399, RT 11.7 min) and unidentified compound with m / z 329.0507 (RT 1.0 min) were also suggested to be end products of DMY degradation. These results provide novel insights on DMY stability and degradation products. Moreover, the heat treatment of DMY aqueous solution was found to gradually reduce the antioxidant activities of DMY, and even destroy the beneficial effect of DMY on the gut microbiota composition.
研究领域:
药学化学
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分析化学
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食品科学
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药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）