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1.
Food Chem ; 336: 127539, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32763730

RESUMO

Hesperidin hydrolysates (HHS) was produced by the hydrolysis of hesperidin (HDN) in previous studies. The potential components in HHS were identified by LC-MS, and minor components (MCS) in HHS were isolated. Antioxidant activities by radical-scavenging capacities, reducing capacity and ß-carotene-linoleate assay, anti-inflammatory effects by inhibiting NO production of RAW 264.7 cells, and α-glucosidase inhibitory effects of HDN, HHS, MCS and henperetin (HTN) were investigated in present study. HHS showed higher radical scavenging activities, higher reducing capacity, and higher inhibitory activity in the ß-carotene-linoleate assay than HDN. HHS inhibited the production of NO and pro-inflammatory cytokines of RAW 264.7 cells more strongly than HDN. HHS also intensively inhibited α-glucosidase activity whereas HDN showed little activity. In addition, the effects of MCS on above activities showed it play a synergistic part with HTN. This work suggested that hydrolyzation of HDN enhance the activities, and provided valuable information on effective utilization of HDN.


Assuntos
Anti-Inflamatórios/química , Antioxidantes/química , Citrus/química , Inibidores Enzimáticos/química , Hesperidina/análise , Animais , Anti-Inflamatórios/farmacologia , Catálise , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Citrus/metabolismo , Inibidores Enzimáticos/metabolismo , Hesperidina/metabolismo , Hesperidina/farmacologia , Hidrólise , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Espectrometria de Massas , Camundongos , Óxido Nítrico/metabolismo , Células RAW 264.7 , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
2.
J Food Sci ; 85(7): 2177-2185, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32672871

RESUMO

Phenolic profiles, antioxidant, antiproliferative, and hypoglycemic activities of the whole Ehretia macrophylla Wall. (EMW) fruit were investigated in the present study. Catechin (CE), o-methoxy benzoic acid (o-MBA), and rosmarinic acid (RA) were the predominant phenolics in free extract, while CE, vanillic acid (VA), and o-MBA were for bound extract. These extracts exhibited potential antioxidant capacity measured by peroxyl radical scavenging capacity (PSC), oxygen radical absorbance capacity (ORAC), and cellular antioxidant activity (CAA) assays. This fruit also possessed dose-dependently antiproliferative activity, and this may be due to the synergistic and additive effects of individual phenolics. Furthermore, EMW fruit showed favorable hypoglycemic activity via inhibition of activities of α-glucosidase and α-amylase, enhancement of glucose consumption, glycogen accumulation, and glycogen synthase 2 (GYS2) activity, and downregulation of activities of glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK). Therefore, EMW fruit has the potential as an ingredient of functional foods to improve human health and shows promising applications with additional health and economical benefits. PRACTICAL APPLICATION: EMW fruit is a plant-based food rich in natural phenolic compounds, which suggesting its potential bioactivities for humans such as antioxidant, antiproliferative, and hypoglycemic activities. Our findings would provide a logical strategy to promote the comprehensive utilization of phenolics in EMW fruit with both health and economical benefits.


Assuntos
Antioxidantes/química , Boraginaceae/química , Hipoglicemiantes/química , Fenóis/química , Extratos Vegetais/química , Antioxidantes/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Frutas/química , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Humanos , Hipoglicemiantes/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/química , alfa-Glucosidases/química
3.
Food Chem ; 331: 127240, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32585546

RESUMO

The present study focused on the phytochemical profiling along with evaluation of in vitro antioxidant, α-glucosidase and α-amylase inhibitory activities of various crudes and fractions obtained from Lepisanthes fruticosa (Roxb) Leenh fruit. Ethanolic seed crude extract exhibited the strongest radical scavenging, ß-carotene bleaching activity, α-glucosidase inhibition and the highest total phenolic content (TPC). Column chromatography afforded various fractions with fraction M4 being the most potent due to the strongest radical scavenging, ß-carotene bleaching, α-glucosidase inhibition and greatest amount of TPC. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of ethanolic seed crude extract and fraction M4 showed the presence of various phytochemicals with antioxidant and antidiabetic properties, which include mostly flavonoids and tannins. The results may suggest that the ethanolic crude seed extract and its fraction could be an excellent source of bioactive phytochemicals with antioxidant and antidiabetic potential.


Assuntos
Antioxidantes/química , Inibidores Enzimáticos/análise , Fenóis/análise , Extratos Vegetais/química , Sapindaceae/química , Cromatografia Líquida de Alta Pressão , Inibidores Enzimáticos/química , Flavonoides/análise , Flavonoides/química , Frutas/química , Frutas/metabolismo , Fenóis/química , Sapindaceae/metabolismo , Espectrometria de Massas em Tandem , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
4.
Food Chem ; 324: 126847, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32344340

RESUMO

This study aimed to investigate the inhibitory effect of chestnut inner skin extract (CISE) on the activity of postprandial blood sugar-related enzymes. In total, 12 flavonoids were identified by HPLC-TOF-MS. CISE showed strong and weak inhibition on α-amylase and α-glucosidase, with the IC50 of 27.2 and 2.3 µg/mL, respectively. The inhibition modes of CISE against α-amylase and α-glucosidase were mixed-type and non-competitive type, respectively. Epicatechin gallate noncompetitively inhibited α-amylase, α-glucosidase and dipeptidyl peptidase IV (DPP-IV). Analysis by ultraviolet-visible spectroscopy, fluorescence spectroscopy and circular dichroism suggested that flavonoids altered the hydrophobicity and microenvironment of these enzymes. CISE decreased the starch bioavailability by reducing the enzymatic hydrolysis rate and increasing the fraction of undigested starch. The extract reduced the rapidly digestible starch and increased the resistant starch after incorporation into A-, B- or C- crystallinity starch. Thus, the chestnut inner skin is a useful resource for regulating postprandial blood sugar level.


Assuntos
Inibidores da Dipeptidil Peptidase IV/farmacologia , Fagaceae/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Extratos Vegetais/farmacologia , Disponibilidade Biológica , Catequina/análogos & derivados , Catequina/farmacologia , Dipeptidil Peptidase 4/química , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/química , Flavonoides/análise , Inibidores de Glicosídeo Hidrolases/química , Nozes/química , Extratos Vegetais/química , Amido/farmacocinética , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/química , alfa-Glucosidases/química
5.
J Food Sci ; 85(4): 1060-1069, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32147838

RESUMO

Inonotus obliquus is a traditional mushroom well known for its therapeutic value. In this study, various solvent fractions of I. obliquus were preliminarily screened for their antioxidant, α-amylase and α-glucosidase inhibition properties. To improve the drug delivery, the active fraction (ethyl acetate fraction) of I. obliquus was synthesized into fungisome (ethyl acetate phophotidyl choline complex, EAPC) and its physical parameters were assessed using Fourier transform infrared spectroscopy (FTIR), High performance liquid chromatography (HPLC), Scanning electron microscope (SEM), and ς potential analysis. Then normal human hepatic L02 cells was used to evaluate the cytotoxicity of EAPC. The results showed that EA fraction possesses significant free radical scavenging, α-amylase and α-glucosidase inhibition properties. FTIR, SEM, and HPLC analysis confirmed the fungisome formation. The particle size of EAPC was 102.80 ± 0.42 nm and the ς potential was -54.30 ± 0.61 mV. The percentage of drug entrapment efficiency was 97.13% and the drug release rates of EAPC in simulated gastric fluid and simulated intestinal fluid were 75.04 ± 0.29% and 93.03 ± 0.36%, respectively. EAPC was nontoxic to L02 cells, however it could selectively fight against the H2 O2 induced oxidative damage in L02 cells. This is the first study to provide scientific information to utilize the active fraction of I. obliquus as fungisome. PRACTICAL APPLICATIONS: Inonotus obliquus (IO) is a traditional medicinal fungus. The extracts of IO have obvious antioxidant and hypoglycemic activities. Ethyl acetate (EA) fraction of IO was encapsulated in liposomes to form EAPC. EAPC has a sustained-release effect. It has nontoxic to L02 cells and could protect L02 cells from oxidative damage caused by hydrogen peroxide. This study could provide new ideas for the treatment of diabetes.


Assuntos
Agaricales/química , Antioxidantes/farmacologia , Basidiomycota/química , Inibidores Enzimáticos/farmacologia , Peróxido de Hidrogênio/toxicidade , Extratos Vegetais/farmacologia , alfa-Amilases/antagonistas & inibidores , Antioxidantes/química , Antioxidantes/isolamento & purificação , Linhagem Celular , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , alfa-Amilases/química , alfa-Glucosidases/química
6.
Food Chem ; 317: 126346, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32070843

RESUMO

The inhibitory mechanisms of ferulic acid against α-amylase and α-glucosidase were investigated by enzyme kinetic analysis, circular dichroism (CD), Fourier-transform infrared (FT-IR) spectroscopy, fluorescence quenching and molecular docking. Results indicated that ferulic acid strongly inhibited α-amylase (IC50: 0.622 mg ml-1) and α-glucosidase (IC50: 0.866 mg ml-1) by mixed and non-competitive mechanisms, respectively. CD spectra and fluorescence intensity measurements confirmed that the secondary structure of α-amylase and α-glucosidase were changed and the microenvironments of certain amino acid residues were modulated by the binding of ferulic acid. FT-IR spectra indicated that the interaction between ferulic acid and α-amylase/α-glucosidase mainly involved in non-covalent bonds. Molecular docking further demonstrated that the interaction forces between ferulic acid and α-amylase/α-glucosidase were hydrogen bonds, with the binding energy of -5.30 to -5.10 and -5.70 kcal mol-1, respectively. This study might provide a theoretical basis for the designing of novel functional foods with ferulic acid.


Assuntos
Ácidos Cumáricos/metabolismo , Inibidores de Glicosídeo Hidrolases/metabolismo , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo , Sítios de Ligação , Ácidos Cumáricos/química , Inibidores de Glicosídeo Hidrolases/química , Ligação de Hidrogênio , Cinética , Simulação de Acoplamento Molecular , Estrutura Secundária de Proteína , Termodinâmica , alfa-Amilases/química , alfa-Glucosidases/química
7.
Sci Rep ; 10(1): 3530, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32103043

RESUMO

Butea monosperma is one of the extensively used plants in traditional system of medicines for many therapeutic purposes. In this study, the antioxidant activity, α-glucosidase and α-amylase inhibition properties of freeze drying assisted ultrasonicated leaf extracts (hydro-ethanolic) of B. monosperma have been investigated. The findings revealed that 60% ethanolic fraction exhibited high phenolic contents, total flavonoid contents, highest antioxidant activity, and promising α-glucosidase and α-amylase inhibitions. The UHPLC-QTOF-MS/MS analysis indicated the presence of notable metabolites of significant medicinal potential including apigenin, apigenin C-hexoside C-pentoside, apigenin C-hexoside C-hexoside, apigenin-6,8-di-C-pentoside and genistin etc., in B. monosperma leave extract. Docking studies were carried out to determine the possible role of each phytochemical present in leaf extract. Binding affinity data and interaction pattern of all the possible phytochemicals in leaf extract of B. monosperma revealed that they can inhibit α-amylase and α-glucosidase synergistically to prevent hyperglycemia.


Assuntos
Butea/química , Inibidores de Glicosídeo Hidrolases/química , Hipoglicemiantes/química , Compostos Fitoquímicos/química , Extratos Vegetais/química , Folhas de Planta/química , Etanol/química , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/química , alfa-Glucosidases/química
8.
Food Chem ; 313: 126099, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31927321

RESUMO

Diabetes mellitus is a metabolic disorder characterized by hyperglycemia, which can be counteracted by inhibition of α-glucosidase and α-amylase, both involved in the carbohydrate metabolism. Fourteen C-glucosidic ellagitannins and three galloylated glucoses were studied as potential α-glucosidase and α-amylase inhibitors. Most of the compounds were found to be moderate inhibitors of α-amylase, but potent inhibitors of α-glucosidase, showing low-micromolar IC50 values, far lower than that of the antidiabetic drug acarbose. This selectivity can be an advantage for their possible application as functional food ingredients with anti-diabetic properties because strong α-amylase inhibition generally causes undesired side effects. The best inhibitors were selected for further studies. Intrinsic fluorescence measurements confirmed their high affinity towards α-glucosidase, highlighting a static quenching mechanism. Circular dichroism measurements and kinetics of inhibition indicated that the most active C-glucosidic ellagitannin roburin D (RobD) is a competitive inhibitor, whereas α-pentagalloylglucose (α-PGG) acts as a mixed-type inhibitor.


Assuntos
Taninos Hidrolisáveis/química , Hipoglicemiantes/química , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo , Dicroísmo Circular , Glucosídeos/química , Taninos Hidrolisáveis/metabolismo , Hipoglicemiantes/metabolismo , Concentração Inibidora 50 , Cinética , Espectrometria de Fluorescência , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases/química
9.
J Agric Food Chem ; 68(6): 1555-1562, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31986026

RESUMO

Passiflora edulis Sims (passion fruit) seeds are often discarded as byproducts during juice processing. In fact, the seeds are of considerable commercial value in the food and cosmetics industry because of their rich polyphenols, especially piceatannol. In this study, high-speed countercurrent chromatography (HSCCC) was applied for the separation of stilbene polyphenols from passion fruit seeds. The n-hexane-ethyl acetate-methanol-water (1:2:1:2.8, v/v) was found to be the optimum two-phase solvent for the preparation of two major stilbenes, scirpusin B (8) and piceatannol (9) with purities of 90.2% and 94.8%, respectively. In addition, a continuous semipreparative HPLC was applied to further purify the HSCCC fractions containing minor stilbenes and obtain four new piceatannol derivatives (1-4) along with three known ones (5-7). The structures of these new compounds were determined using spectroscopic methods, including NMR, high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), and circular dichroism (CD). The isolated compounds were evaluated for α-glucosidase inhibitory activities in vitro. The result suggested that all of them exhibited more significant activity than acarbose, and passiflorinol B (2) had the strongest activity, with a IC50 value of 1.7 µM.


Assuntos
Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Passiflora/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Estilbenos/química , Estilbenos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente , Frutas/química , Sementes/química , alfa-Glucosidases/química
10.
Carbohydr Polym ; 230: 115586, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887942

RESUMO

α-Glycosidase is an essential target for the management of postprandial serum glucose in diabetic patients. Therefore, the interest has been growing in the screening of α-glycosidase inhibitor from natural resource. In the present study, the structure and α-glycosidase inhibitory activity of a polysaccharide (named as ACPP-1) from Aconitum coreanum were investigated. Based on the results from high performance gel permeation chromatography, GC-MS and 1D/2D nuclear magnetic resonance spectroscopy, ACPP-1 was a highly-linear polysaccharide with a molecular weight of 34.0 kD and containing over 90 % of glucose. It was composed of (1→4)-α-d-Glcp and α-Araf. ACPP-1 exhibited a dose-dependent inhibitory eff ;ect against α-glycosidase activity in vitro and the IC50 value was ∼0.8 mg/mL. In oral starch tolerance test, treatment with ACPP-1 (800 mg/kg) significantly improved the starch tolerance in mice. Taken together, this study provided a potential intervention and management for postprandial hyperglycemia by the polysaccharide fraction from A. coreanum.


Assuntos
Aconitum/química , Inibidores de Glicosídeo Hidrolases/química , Polissacarídeos/química , alfa-Glucosidases/química , Animais , Cromatografia em Gel , Inibidores de Glicosídeo Hidrolases/farmacologia , Humanos , Camundongos , Peso Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Polissacarídeos/ultraestrutura , alfa-Glucosidases/farmacologia , alfa-Glucosidases/ultraestrutura
11.
Sci Rep ; 10(1): 47, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31913341

RESUMO

Nucleos(t)ide analog (NA) therapy has proven effective in treating chronic hepatitis B. However, NAs frequently result in viral relapse after the cessation of therapy. This is because NAs cannot fully eliminate the viral episomal covalently closed circular DNA (cccDNA) in the nucleus. In this study, we identified small molecular compounds that control host factors related to viral replication using in silico screening with simulated annealing based on bioinformatics for protein-ligand flexible docking. Twelve chemical compound candidates for alpha-glucosidase (AG) inhibitors were identified from a library of chemical compounds and used to treat fresh human hepatocytes infected with HBV. They were then monitored for their anti-viral effects. HBV replication was inhibited by one candidate (1-[3-(4-tert-butylcyclohexyl)oxy-2-hydroxypropyl]-2,2,6,6-tetramethylpiperidin-4-ol) in a dose-dependent manner. This compound significantly reduced ccc DNA production, compared to Entecavir (p < 0.05), and had a lower anti-AG effect. Gene expression analysis and structural analysis of this compound showed that its inhibitive effect on HBV was via interaction with Sp1. The nuclear transcription factor Sp1 acts on multiple regions of HBV to suppress HBV replication. Identifying candidates that control nuclear transcription factors facilitate the development of novel therapies. Drugs with a mechanism different from NA are promising for the elimination of HBV.


Assuntos
Antivirais/farmacologia , Desenvolvimento de Medicamentos , Inibidores de Glicosídeo Hidrolases/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/tratamento farmacológico , Fator de Transcrição Sp1/metabolismo , Replicação Viral/efeitos dos fármacos , Antivirais/química , DNA Circular/genética , DNA Viral/genética , Inibidores de Glicosídeo Hidrolases/química , Hepatite B/virologia , Vírus da Hepatite B/isolamento & purificação , Hepatócitos/efeitos dos fármacos , Hepatócitos/virologia , Ensaios de Triagem em Larga Escala , Humanos , alfa-Glucosidases/química
12.
Eur J Med Chem ; 189: 112013, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31972390

RESUMO

In this study, two series of coumarin derivatives 5a∼i and 6a∼i were synthesized, and their inhibitory activity against α-glucosidase was determined. The results indicated that most of the synthesized derivatives exhibited prominent inhibitory activities against α-glucosidase. Among them, compounds 5a and 5b showed the strongest inhibition with the IC50 values of 19.64 µM and 12.98 µM, respectively. Enzyme kinetic studies of compounds 5a and 5b proved that their inhibition was reversible and a mixed type. The KI and KIS values of compound 5a were calculated to be 27.39 µM and 13.02 µM, respectively, and the corresponding values for compound 5b being 27.02 µM and 13.65 µM, respectively. The docking studies showed that compound 5b could be inserted into the active pocket of α-glucosidase and form hydrogen bonds with LYS293 to enhance the binding affinity.


Assuntos
Cumarínicos/química , Inibidores de Glicosídeo Hidrolases/síntese química , Inibidores de Glicosídeo Hidrolases/farmacologia , alfa-Glucosidases/química , Ligação de Hidrogênio , Cinética , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
13.
J Sci Food Agric ; 100(5): 1998-2006, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31849067

RESUMO

BACKGROUND: In this investigation, the chemical and biological profiles of three Turkish Crataegus species (Crataegus orientalis, Crataegus szovitsii and Crataegus tanacetifolia) were studied in order to provide the first comprehensive characterization and their health-promoting potential. In this respect, polyphenolic profiles were evaluated using ultrahigh-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. The in vitro antioxidant activities of the Crataegus samples were evaluated by using free-radical scavenging, phosphomolybdenum, ferrous-ion chelating, and reducing power assays. The inhibitory activities against α-glucosidase, amylase, cholinesterases (acetylcholinesterase (AChE) and butyrylcholinesterase (BChE)), and tyrosinase were also established. RESULTS: The untargeted metabolomic approach highlighted the effect of both extraction types and species on the phenolic profiles of different Crateagus tissues (i.e. leaves and twigs). The methanolic extracts showed the maximum radical scavenging and reducing activity in all test systems, whereas for ferrous-ion chelating assays the decocted and infused extracts showed the highest activity. Only the methanolic extracts were effective against AChE and BChE. The extract tested showed remarkable inhibitory effects against tyrosinase and α-glucosidase, whereas all the extracts exhibited modest inhibition against α-amylase. Overall, the twig extracts of the three species studied showed superior antioxidant and enzyme inhibitory activities. CONCLUSION: On the basis of these results, the three Crataegus species can be classified as potent bioresources for high-value phytochemicals, which warrant further investigations for developing novel nutraceuticals. © 2019 Society of Chemical Industry.


Assuntos
Crataegus/química , Inibidores Enzimáticos/química , Extratos Vegetais/química , Antioxidantes/metabolismo , Butirilcolinesterase/química , Crataegus/metabolismo , Inibidores Enzimáticos/metabolismo , Metabolômica , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/química , Fenóis/química , Fenóis/metabolismo , Extratos Vegetais/metabolismo , Turquia , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/química , alfa-Glucosidases/química
14.
J Sci Food Agric ; 100(2): 509-516, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31487036

RESUMO

BACKGROUND: Emblica officinalis, known as amla in Ayurveda, has been used as a folk medicine to treat numerous pathological conditions, including diabetes. However, the novel extract of E. officinalis fruit extract (amla fruit extract, AFE, Saberry®) containing 100 g kg-1 ß-glucogallin along with hydrolyzable tannins has not yet been extensively studied for its antidiabetic potential. OBJECTIVE: The aim of this study was to investigate the antidiabetic and antioxidant activities of AFE and its stability during gastric stress as well as its thermostability. METHODS: The effect of AFE on the inhibition of pancreatic α-amylase and salivary α-amylase enzymes was studied using starch and yeast α-glucosidase enzyme using 4-nitrophenyl α-d-glucopyranoside as substrate. Further, 2,2-diphenyl-1-picrylhydrazyl radical scavenging and reactive oxygen species inhibition assay was performed against AFE. RESULTS: AFE potently inhibited the activities of α-amylase and α-glucosidase in a concentration-dependent manner with half maximal inhibitory concentration (IC50 ) values of 135.70 µg mL-1 and 106.70 µg mL-1 respectively. Furthermore, it also showed inhibition of α-glucosidase (IC50 562.9 µg mL-1 ) and dipeptidyl peptidase-4 (DPP-4; IC50 3770 µg mL-1 ) enzyme activities. AFE is a potent antioxidant showing a free radical scavenging activity (IC50 2.37 µg mL-1 ) and protecting against cellular reactive oxygen species (IC50 1.77 µg mL-1 ), and the effects elicited could be attributed to its phytoconstituents. CONCLUSION: AFE showed significant gastric acid resistance and was also found to be thermostable against wet heat. Excellent α-amylase, α-glucosidase, and DPP-4 inhibitory activities of AFE, as well as antioxidant activities, strongly recommend its use for the management of type 2 diabetes mellitus. © 2019 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Antioxidantes/química , Inibidores da Dipeptidil Peptidase IV/química , Frutas/química , Inibidores de Glicosídeo Hidrolases/química , Phyllanthus emblica/química , Extratos Vegetais/química , Antioxidantes/isolamento & purificação , Diabetes Mellitus Tipo 2/enzimologia , Dipeptidil Peptidase 4/química , Inibidores da Dipeptidil Peptidase IV/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Extratos Vegetais/isolamento & purificação , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/química , alfa-Glucosidases/química
15.
Molecules ; 24(23)2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31783621

RESUMO

Twenty-one natural and unnatural phenolic compounds containing a carbohydrate moiety were synthesized and their structure-activity relationship (SAR) was evaluated for α-glucosidase inhibition and antioxidative activity. Varying the position of the galloyl unit on the 1,5-anhydro-d-glucitol (1,5-AG) core resulted in changes in the α-glucosidase inhibitory activity and notably, particularly strong activity was demonstrated when the galloyl unit was present at the C-2 position. Furthermore, increasing the number of the galloyl units significantly affected the α-glucosidase inhibition, and 2,3,4,6-tetra-galloyl-1,5-AG (54) and 2,3,4,6-tetra-galloyl-d-glucopyranose (61) exhibited excellent activities, which were more than 13-fold higher than the α-glucosidase inhibitory activity of acertannin (37). Moreover, a comparative structure-activity study suggested that a hemiacetal hydroxyl functionality in the carbohydrate core and a biaryl bond of the 4,6-O-hexahydroxydiphenoyl (HHDP) group, which are components of ellagitannins including tellimagrandin I, are not necessary for the α-glucosidase inhibitory activity. Lastly, the antioxidant activity increased proportionally with the number of galloyl units.


Assuntos
Antioxidantes/química , Inibidores de Glicosídeo Hidrolases/química , Polifenóis/química , alfa-Glucosidases , Antioxidantes/síntese química , Antioxidantes/farmacologia , Carboidratos/química , Desoxiglucose/química , Ácido Gálico/análogos & derivados , Ácido Gálico/síntese química , Ácido Gálico/química , Glucosídeos/síntese química , Glucosídeos/química , Inibidores de Glicosídeo Hidrolases/síntese química , Inibidores de Glicosídeo Hidrolases/farmacologia , Estrutura Molecular , Extratos Vegetais/química , Polifenóis/síntese química , Polifenóis/farmacologia , Relação Estrutura-Atividade , alfa-Glucosidases/química
16.
Mikrochim Acta ; 186(12): 818, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31748845

RESUMO

A turn-on ratiometric fluorescent assay is described for the determination of the activity of enzymes participating in ascorbic acid-forming reactions. Blue-emitting carbon dots (bCDs; with excitation/emission wavelength at 380/450 nm) serve as fluorescent indicator. Their fluorescence is reduced by Fe3+ ions via an inner filter effect. Yellow-emitting CDs (yCDs; with excitation/emission wavelength at 380/550 nm) serve as internal reference because their fluorescence is insensitive to Fe3+. Upon exposure to ascorbic acid (AA), Fe3+ is reduced to Fe2+. Hence, the fluorescence of the bCDs is restored. Thus, enzymes participating in AA-related reactions such as α-glucosidase (α-Glu) and alkaline phosphatase (ALP) can be determined. α-Glu activity was quantified in the range from 0.13 to 6.70 U mL-1, and ALP activity was determined between 2.0 and 130 U L-1. Endowed with excellent sensitivity, selectivity and low background signals, the method may also be used to screen the inhibitors of α-Glu and ALP. Graphical abstractSchematic representation of a redox modulated ratiometric fluorometric method based on the use of dual-color carbon dots for determination of the activity of enzymes participating in ascorbic acid-related reactions. Blue-emitting carbon dots (bCDs) serve as fluorescent indicator while yellow-emitting CDs (yCDs) serve as internal reference.


Assuntos
Fosfatase Alcalina/metabolismo , Ácido Ascórbico/metabolismo , Carbono/química , Cor , Fluorometria , Pontos Quânticos/química , alfa-Glucosidases/metabolismo , Fosfatase Alcalina/antagonistas & inibidores , Fosfatase Alcalina/sangue , Ácido Ascórbico/química , Humanos , Oxirredução , Tamanho da Partícula , Propriedades de Superfície , alfa-Glucosidases/sangue , alfa-Glucosidases/química
17.
Molecules ; 24(22)2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31717689

RESUMO

Enzymatic inhibitions of crude extracts and their constituents from Zingiberaceae against both rat intestinal α-glucosidase and porcine pancreatic lipase were investigated. Structure-activity relationships using their derivatives were also investigated. The rhizomes extract of mango ginger, Curcuma amada showed remarkable inhibitory activity in the screening test. Two natural labdane diterpenes 1 and 2 and a drimane sesquiterpene 3 were major constituents isolated from this hexane extract. Among them, (E)-labda-8(17),12-diene-15,16-dial (1) was the most prominent compound and showed inhibitory activity against both α-glucosidase and lipase. Derivatives 4-10 from compound 1 were prepared and evaluated using inhibitory assays with these enzymes. The reduced derivative 4 maintained α-glucosidase inhibitory activity, but had decreased pancreatic lipase inhibitory activity compared with parent compound 1. Other tested derivatives of compound 1, including acetates 5-7 and oxidative derivatives 8-10, had very weak α-glucosidase inhibitory activity. Most of these compounds showed moderate pancreatic lipase inhibitory activity. However, only sesquiterpene albicanal (3) showed drastically decreased pancreatic lipase activity compared with 1. These findings suggested that molecular size was essential for enzymatic inhibitory activities of these compounds. These results demonstrated that mango ginger may be useful for the prevention of obesity and being overweight.


Assuntos
Diterpenos/farmacologia , Inibidores Enzimáticos/farmacologia , Gengibre/química , Pancrelipase/química , Extratos Vegetais/farmacologia , alfa-Glucosidases/química , Animais , Diterpenos/química , Diterpenos/isolamento & purificação , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Ratos
18.
Molecules ; 24(22)2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31698833

RESUMO

Twelve terpenoids were evaluated in the treatment of type 2 diabetes mellitus: seven monoterpenes (geranyl acetate (1), geranic acid (2), citral (3), geraniol (4), methyl geranate (5), nerol (6), and citronellic acid (7)), three sesquiterpenes (farnesal (8), farnesol (9), and farnesyl acetate (10)), one diterpene (geranylgeraniol (11)), and one triterpene (squalene (12)) were selected to carry out a study on normoglycemic and streptozotocin-induced diabetic mice. Among these, 2, 3, 7, 8, 9, and 10 showed antihyperglycemic activity in streptozotocin-induced diabetic mice. They were then selected for evaluation in oral sucrose and lactose tolerance tests (OSTT and OLTT) as well as in an oral glucose tolerance test (OGTT). In the OSTT and OLTT, compounds 3, 7, 8, 9, and 10 showed a reduction in postprandial glucose peaks 2 h after a sucrose or lactose load (comparable to acarbose). In the case of the OGTT, 2, 7, 8, 9, and 10 showed a reduction in postprandial glucose peaks 2 h after a glucose load (comparable to canagliflozin). Our results suggest that the control of postprandial hyperglycemia may be mediated by the inhibition of disaccharide digestion, such as sucrose and lactose, and the regulation of the absorption of glucose. The first case could be associated with an ∝ -glucosidase inhibitory effect and the second with an inhibition of the sodium-glucose type 1 (SGLT-1) cotransporter. Finally, five acyclic terpenes may be candidates for the development and search for new α-glucosidase and SGLT-1 cotransporter inhibitors.


Assuntos
Glicemia , Terpenos/química , Terpenos/farmacologia , Animais , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Masculino , Camundongos , Estrutura Molecular , Transportador 1 de Glucose-Sódio/antagonistas & inibidores , Transportador 1 de Glucose-Sódio/química , Relação Estrutura-Atividade , Terpenos/sangue , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
19.
J Food Sci ; 84(12): 3473-3482, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31721214

RESUMO

This work aimed to investigate the phytochemical composition, nutritional value, antioxidant, antihemolytic, antihyperglycemic, and antiproliferative activities of flaxleaf fleabane (Conyza bonariensis) leaves. Different concentrations of water and ethanol (0:100, 25:75, 50:50, 75:25, and 100:0 v/v) were used in the extraction process and results showed that the hydroalcoholic extract (50:50 v/v) presented the highest total phenolics, ortho-diphenolics, Folin-Ciocalteu reducing capacity, FRAP, and Fe2+ chelating ability values. Flaxleaf fleabane leaves (FFL) contained 19.6 g/100 g of fibers and 26 g/100 g of proteins. Ellagic acid, procyanidin A2, caffeic, rosmarinic, gallic, and 2,5-dihydroxybenzoic acids were the main phenolics. This phenolic-rich extract inhibited the lipid oxidation of Wistar rat brain (IC50 = 863.0 mg GAE/L), inhibited α-glucosidase activity (IC50 = 435.4 µg/mL), protected human erythrocytes against mechanical hemolysis at different osmolarity conditions, and showed cytotoxic/antiproliferative effects against human ileocecal adenocarcinoma cells (HCT8; IC50 = 552.6 µg/mL) but no cytotoxicity toward noncancerous human lung fibroblast (IMR90). Overall, FFL showed potential to be explored by food companies to be a source of proteins, natural color substances, and phenolic compounds. PRACTICAL APPLICATION: Flaxleaf fleabane leaves (FFL) are usually burnt or partially given to cattle, without a proper utilization as a source of nutrients for human nutrition. Here, we studied the nutritional composition, phenolic composition, and toxicological aspects of FFL using different biological protocols. FFL was proven to be a rich source of proteins and dietary fibers and showed antioxidant activity measured by chemical and in vitro biological assays. Additionally, as it did protected human red cells and did not show cytotoxicity, we assume FFL has relative safety to be consumed as a nonconventional edible plant.


Assuntos
Conyza/química , Compostos Fitoquímicos/análise , Animais , Antioxidantes/análise , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Conyza/metabolismo , Alimento Funcional/análise , Inibidores de Glicosídeo Hidrolases/análise , Inibidores de Glicosídeo Hidrolases/metabolismo , Inibidores de Glicosídeo Hidrolases/farmacologia , Humanos , Valor Nutritivo , Fenóis/análise , Fenóis/metabolismo , Fenóis/farmacologia , Compostos Fitoquímicos/metabolismo , Compostos Fitoquímicos/farmacologia , Folhas de Planta/química , Folhas de Planta/metabolismo , Plantas Comestíveis/química , Plantas Comestíveis/metabolismo , Ratos , Ratos Wistar , alfa-Glucosidases/química
20.
Molecules ; 24(21)2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31652777

RESUMO

A new class of triazinoindole-bearing thiosemicarbazides (1-25) was synthesized and evaluated for α-glucosidase inhibitory potential. All synthesized analogs exhibited excellent inhibitory potential, with IC50 values ranging from 1.30 ± 0.01 to 35.80 ± 0.80 µM when compared to standard acarbose (an IC50 value of 38.60 ± 0.20 µM). Among the series, analogs 1 and 23 were found to be the most potent, with IC50 values of 1.30 ± 0.05 and 1.30 ± 0.01 µM, respectively. The structure-activity relationship (SAR) was mainly based upon bringing about different substituents on the phenyl rings. To confirm the binding interactions, a molecular docking study was performed.


Assuntos
Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/síntese química , Simulação de Acoplamento Molecular , Tioureia , alfa-Glucosidases/química , Relação Estrutura-Atividade , Tioureia/análogos & derivados , Tioureia/síntese química , Tioureia/química
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