Interaction mechanism between green tea extract and human α-amylase for reducing starch digestion

Miao, Ming; Jiang, Bo; Jiang, Huan; Zou, Tao; Li, Xingfeng

doi:10.1016/j.foodchem.2015.02.049

Cited by 128 publications

(77 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Catechin (C), epicatechin (EC), epigallocatechin (EGC), epigallocatechin gallate (EGCG), epicatechin gallate (ECG), theaflavin, theaflavin-3'-gallate (TF1), theaflavin-3, 3'-digallate (TF2) are the prominent polyphenols in aqueous green, oolong or black tea extracts (Serpen, Pelvan, Alasalvar, Mogol, Yavuz, Gokmen, et al, 2012). The inhibitory activities of the tea polyphenols against α-amylase have been studied, and the results showed that polyphenols with a galloyl moiety in the molecular structures showed greater enzyme inhibition than those without galloyl moiety, indicated by IC 50 values (Hara & Honda, 1990) (Miao, Jiang, Jiang, Li, Cui, & Jin, 2013;Miao, Jiang, Jiang, Zhang, & Li, 2015). Therefore, 3 or 3'-galloyl groups on the C or C' ring ( Fig.…”

Section: Galloyl Moietymentioning

confidence: 99%

“…As there are fluorophores in amylase, like tryptophan and tyrosine, α-amylase can emit fluorescence at certain excitation wavelengths, and the fluorescence intensity is directly related with the amount of active enzyme in solution (Soares, Mateus, & de Freitas, 2007 (Soares, Mateus, & de Freitas, 2007). Therefore, in recent studies, EGCG was shown to quench the fluorescence of α-amylase in a dynamic mechanism because its Stern-Volmer plot was linear and its k q was determined to be lower than 1×10 10 M -1 s -1 (Fei, et al, 2014;Miao, Jiang, Jiang, Zhang, & Li, 2015), while sorghum procyanidins was shown to apparently statically quench the α-amylase fluorescence with an upward Stern-Volmer plot and a k q that was much higher than 1×10 10 M -1 s -1 (Cai, Yu, Xu, Liu, & Yang, 2015).…”

Section: Fluorescence Quenchingmentioning

confidence: 99%

“…Through the docking study, hydrogen bonding between the hydroxyl groups of polyphenols and the amino acids residues (Asp 197 , Glu 233 and Asp 300 ) at the active sites of α-amylase was suggested, as well as hydrophobic interactions between the aromatic groups of polyphenols (benzene rings) and the enzyme (Trp 59 ) (Lo Piparo, Scheib, Frei, Williamson, Grigorov, & Chou, 2008;Miao, Jiang, Jiang, Zhang, & Li, 2015). The total binding energy (kJ/mol) of polyphenol with α-amylase can be obtained from the docking study as well.…”

Section: Molecular Dockingmentioning

confidence: 99%

“…It was found that theaflavins had a higher inhibitory activity than catechins, and only catechins with a galloyl substituent at the 3-position exhibited measurable inhibition of α-amylase (Hara & Honda, 1990). A 3 and/or 3'-galloyl moiety in catechin and related structures was consistently found to increase α-amylase inhibition presumably through enhanced association with the active site of the enzyme (Miao, Jiang, Jiang, Li, Cui, & Jin, 2013;Miao, Jiang, Jiang, Zhang, & Li, 2015).…”

Section: Teamentioning

confidence: 99%

“…From an estimate based on typical compositions, there is about 0.75 mg/mL GTE in one cup of green tea (one tea bag in 200 mL hot water). Therefore, after ingestion of one cup of green tea, more than 0.3 mg/mL of effective GTE may reach the small intestine, which would approach the IC 50 values for α-amylase inhibition (Miao, Jiang, Jiang, Zhang, & Li, 2015). Even so, in practice, the interactions of tea extracts with complex digestive juices, tissues and food components (like protein, plant fibre, etc.)…”

Section: Teamentioning

confidence: 99%

See 4 more Smart Citations

Studying the interactions between tea polyphenols and α-amylase

Sun¹

View full text Add to dashboard Cite

Dixon, Cornish-Bowden and Lineweaver-Burk plot analyses were applied to study the detailed kinetics of inhibition of porcine pancreatic α-amylase (PPA) by tea polyphenols.Fluorescence quenching (FQ), differential scanning calorimetry (DSC) and isothermal titration calorimetry (ITC) were combined with the kinetics of inhibition to elucidate the mechanism of binding interactions of tea polyphenols and PPA. Then, the reciprocal of competitive inhibition constant (1/K ic ), fluorescence quenching constant (K FQ ) and binding constant (K itc ) obtained from these measurements were compared and correlated to analyse the relations between PPA inhibition and binding behaviour. The role of the galloyl moiety in binding of catechins and theaflavins with PPA was highlighted as well. In addition, the effects of three soluble polysaccharides (citrus pectin (CP), wheat arabinoxylan (WAX) and oat β-glucan (OBG)) on the inhibition of PPA by tea polyphenols were studied through PPA inhibition, IC 50 value, inhibition kinetics and fluorescence quenching methods. Furthermore, the effects of tea polyphenols on binding of PPA with normal maize starch granules were studied in terms of binding ratio, dissociation constant (K d ) and binding rate. Then, the association constant (1/K d ), 1/K ic and K FQ of tea polyphenols were correlated to analyse the effects of PPA inhibition on the binding of the enzyme with starch.The results show that green, oolong and black tea extracts, epigallocatechin gallate, theaflavin-3, 3'-digallate and tannic acid were competitive inhibitors of PPA, whereas epicatechin gallate, theaflavin-3'-gallate and theaflavin were mixed-type inhibitors with both competitive and uncompetitive inhibitory characteristics. Only catechins with a galloyl substituent at the 3-position showed measurable inhibition. K ic values were lower for theaflavins than catechins, with the lowest value for theaflavin-3, 3'-digallate. The lower K ic than the uncompetitive inhibition constant for the mixed-type inhibitors suggests that they bind more tightly with free PPA than with the PPA-starch complex. A 3 and/or 3'-galloyl moiety in catechin and theaflavin structures was consistently found to increase inhibition of PPA through enhanced association with the enzyme active site. A higher quenching effect of polyphenols corresponded to a stronger inhibitory activity against PPA. The red-shift of maximum emission wavelength of PPA bound with some polyphenols indicated a potential IV

show abstract

Section: Galloyl Moietymentioning

confidence: 99%

Section: Fluorescence Quenchingmentioning

confidence: 99%

Section: Molecular Dockingmentioning

confidence: 99%

Section: Teamentioning

confidence: 99%

Section: Teamentioning

confidence: 99%

See 3 more Smart Citations

Studying the interactions between tea polyphenols and α-amylase

Sun¹

View full text Add to dashboard Cite

show abstract

Elucidation of alpha‐amylase inhibition by natural shikimic acid derivates regarding the infrequent uncompetitive inhibition mode and structure–activity relationship

et al. 2023

View full text Add to dashboard Cite

The α‐amylase inhibition and binding behaviors of shikimic acid and its structural analogues were studied. Uncompetitive inhibition characteristic of shikimic acid was identified through several linear transformation equations of enzymatic data considering the good linearity. Interestingly, the change in concentrations of starch would not decrease the inhibitory effects of shikimic acid with various concentrations used in present study. The inhibitory effect reduced greatly after the ethyl esterification of shikimic acid. Gallic acid was distinguished from shikimic acid by a benzene ring and exhibited lower inhibition than shikimic acid. Shikimic acid affected the α‐amylase structure by binding to the non‐active site but did not quench the α‐amylase fluorescent intensity. However, gallic acid anchored with a subsite containing some fluorescent residues at the entrance of active pocket, quenching the fluorescence intensity of α‐amylase strongly. The difference in shikimic acid and gallic acid made the changes in their binding sites as well as the binding behavior. Conclusively, the carboxyl and hexatomic ring with one double‐bond played an important role in binding of shikimic acid with the non‐active sites of α‐amylase. Shikimic acid has potentials as a functional‐factor in α‐amylase inhibition for controlling the postprandial blood sugar level.

show abstract

Structure and in vitro digestibility on complex of corn starch with soy isoflavone

Wang

Cui

et al. 2020

Food Science & Nutrition

View full text Add to dashboard Cite

Corn starch, one of the important components of corn, accounts for about 70% of the total mass usually. Starch has a positive effect on maintaining human life and movement, which play a key role obtaining energy from the diet for human. However, long-term consumption of high glycemic index food was positively associated with obesity, hyperglycemia, diabetes typeⅡ, and other metabolic complications (Brand-Miller et al., 2007), prompted researches to reduce digestibility and glycemic index of starch. The protein and phenolic compounds are regarded as safe, eco-friendly, and effective substance that modified digestion and glycemic index of starch, effectively, by

show abstract

Interaction mechanism between green tea extract and human α-amylase for reducing starch digestion

Cited by 128 publications

References 35 publications

Studying the interactions between tea polyphenols and α-amylase

Studying the interactions between tea polyphenols and α-amylase

Elucidation of alpha‐amylase inhibition by natural shikimic acid derivates regarding the infrequent uncompetitive inhibition mode and structure–activity relationship

Structure and in vitro digestibility on complex of corn starch with soy isoflavone

Contact Info

Product

Resources

About