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1.
Int J Mol Sci ; 22(12)2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34203082

RESUMO

Ideal Plant Architecture 1 (IPA1) encodes SQUAMOSA PROMOTER BINDING PROTEIN-LIKE 14 (SPL14) with a pleiotropic effect on regulating rice development and biotic stress responses. To investigate the role of IPA1 in early seedling development, we developed a pair of IPA1/ipal-NILs and found that seed germination and early seedling growth were retarded in the ipa1-NIL. Analysis of the soluble sugar content, activity of amylase, and expression of the α-amylase genes revealed that the starch metabolism was weakened in the ipa1-NIL germinating seeds. Additionally, the content of bioactive gibberellin (GA) was significantly lower than that in the IPA1-NIL seeds at 48 h of imbibition. Meanwhile, the expression of GA synthesis-related gene OsGA20ox1 was downregulated, whereas the expression of GA inactivation-related genes was upregulated in ipa1-NIL seeds. In addition, the expression of OsWRKY51 and OsWRKY71 was significantly upregulated in ipa1-NIL seeds. Using transient dual-luciferase and yeast one-hybrid assays, IPA1 was found to directly activate the expression of OsWRKY51 and OsWRKY71, which would interfere with the binding affinity of GA-induced transcription factor OsGAMYB to inhibit the expression of α-amylase genes. In summary, our results suggest that IPA1 negatively regulates seed germination and early seedling growth by interfering with starch metabolism via the GA and WRKY pathways.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Giberelinas/metabolismo , Oryza/fisiologia , Desenvolvimento Vegetal , Plântula/crescimento & desenvolvimento , Transdução de Sinais , Amido/metabolismo , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas , Germinação/genética , Fenótipo , Ligação Proteica , alfa-Amilases/metabolismo
2.
J Ind Microbiol Biotechnol ; 48(5-6)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34124759

RESUMO

Ammonium hydroxide is conventionally used as an alkaline reagent and cost-effective nitrogen source in enzyme manufacturing processes. However, few ammonia-inducible enzyme expression systems have been described thus far. In this study, genomic-wide transcriptional changes in Bacillus licheniformis CBBD302 cultivated in media supplemented with ammonia were analyzed, resulting in identification of 1443 differently expressed genes, of which 859 genes were upregulated and 584 downregulated. Subsequently, the nucleotide sequences of ammonia-inducible promoters were analyzed and their functionally-mediated expression of amyL, encoding an α-amylase, was shown. TRNA_RS39005 (copA), TRNA_RS41250 (sacA), TRNA_RS23130 (pdpX), TRNA_RS42535 (ald), TRNA_RS31535 (plp), and TRNA_RS23240 (dfp) were selected out of the 859 upregulated genes and each showed higher transcription levels (FPKM values) in the presence of ammonia and glucose than that of the control. The promoters, PcopA from copA, PsacA from sacA, PpdpX from pdpX, Pald from ald, and Pplp from plp, except Pdfp from dfp, were able to mediate amyL expression and were significantly induced by ammonia. The highest enzyme expression level was mediated by Pplp and represented 23% more α-amylase activity after induction by ammonia in a 5-L fermenter. In conclusion, B. licheniformis possesses glucose-independent ammonia-inducible promoters, which can be used to mediate enzyme expression and therefore enhance the enzyme yield in fermentations conventionally fed with ammonia for pH adjustment and nitrogen supply.


Assuntos
Amônia/metabolismo , Bacillus licheniformis/metabolismo , Regiões Promotoras Genéticas , alfa-Amilases/metabolismo , Bacillus licheniformis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , DNA Bacteriano , Fermentação , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Concentração de Íons de Hidrogênio , Microbiologia Industrial , Nitrogênio/metabolismo , Estresse Fisiológico , alfa-Amilases/genética
3.
Braz J Biol ; 82: e239449, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34105678

RESUMO

Alpha amylase, catalyzing the hydrolysis of starch is a ubiquitous enzyme with tremendous industrial applications. A 1698 bp gene coding for 565 amino acid amylase was PCR amplified from Geobacillus thermodenitrificans DSM-465, cloned in pET21a (+) plasmid, expressed in BL21 (DE3) strain of E. coli and characterized. The recombinant enzyme exhibited molecular weight of 63 kDa, optimum pH 8, optimum temperature 70°C, and KM value of 157.7µM. On pilot scale, the purified enzyme efficiently removed up to 95% starch from the cotton fabric indicating its desizing ability at high temperature. 3D model of enzyme built by Raptor-X and validated by Ramachandran plot appeared as a monomer having 31% α-helices, 15% ß-sheets, and 52% loops. Docking studies have shown the best binding affinity of enzyme with amylopectin (∆G -10.59). According to our results, Asp 232, Glu274, Arg448, Glu385, Asp34, Asn276, and Arg175 constitute the potential active site of enzyme.


Assuntos
Escherichia coli , alfa-Amilases , Clonagem Molecular , Estabilidade Enzimática , Escherichia coli/genética , Geobacillus , Concentração de Íons de Hidrogênio , Temperatura , alfa-Amilases/genética , alfa-Amilases/metabolismo
4.
Int J Biol Macromol ; 183: 818-830, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33965481

RESUMO

Tartary buckwheat is one of the few pseudocereals with abundant flavonoids and starch. However, there are different views on the digestibility of Tartary buckwheat starch (TBS) because of its particle size and structure. In this study, fluorescence spectrum methods and enzymatic kinetics were used to investigate the interaction between TBS /two glycosidase (α-amylase and α-glucosidase) and quercetin to explore its digestive properties and provide a perspective regarding the application of TBS in functional starch products. The results showed that the interaction between TBS and quercetin was probably weak hydrophobic force and hydrogen bonding. The inhibitory effect of quercetin on α-amylase was better than that on α-glucosidase. The half inhibitory concentrations (IC50) of quercetin to α-amylase and α- glucosidase was (270 ±â€¯3.31) and (544 ±â€¯9.01) µg/mL, respectively. The intrinsic fluorescence of two enzymes was statically quenched by forming a complex with quercetin. Quercetin also increased the microenvironment hydrophilicity of tryptophan residues in glycosidase. In vitro digestion experiment demonstrated that quercetin and TBS co-gelatinized together was more effective to inhibit TBS hydrolysis than quercetin itself alone. In the first-order kinetic and LOS model, quercetin-starch gel structure and quercetin inhibitory activity against enzymes had synergistic effects of the TBS digestion.


Assuntos
Quercetina/farmacologia , Amido/química , alfa-Amilases/metabolismo , alfa-L-Fucosidase/metabolismo , Fagopyrum , Ligação de Hidrogênio , Hidrólise , Interações Hidrofóbicas e Hidrofílicas , Concentração Inibidora 50 , Cinética , Ligação Proteica , Quercetina/química , alfa-Amilases/química , alfa-L-Fucosidase/química
5.
Biomed Res Int ; 2021: 6652777, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33987444

RESUMO

Background: The leaves of Hagenia abyssinica have been used in the management of diabetes mellitus in Ethiopian folk medicine. Thus, this study is aimed at investigating the in vitro α-amylase and α-glucosidase inhibitory and antioxidant activities of the crude extract and solvent fractions of H. abyssinica leaves. Methods: The in vitro α-amylase and α-glucosidase inhibitory and antioxidant activities of the plant extract were assessed using 3,5-dinitrosalicylic acid (DNSA), p-nitro-phenyl-a-D glucopyranoside (p-NPG), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays, respectively. Each value of percent inhibition of α-amylase, α-glucosidase, and DPPH scavenging effect was presented as means ± SEM (n = 3). Results: The α-amylase inhibitory activity of the crude extract and solvent fractions was found to be concentration-dependent. The strongest activity was exhibited by the crude extract at the highest concentration with a percentage inhibition of 74.52% (IC50, 14.52 µg/ml) followed by water fraction 68.24% (IC50, 16.31 µg/ml), ethyl acetate fraction 61.57% (IC50, 18.73 µg/ml), and chloroform fraction 56.87% (IC50, 21.57 µg/ml) of H. abyssinica leaves. In the α-glucosidase inhibition assay, the maximum activity was exhibited by the aqueous fraction 62.54% (IC50, 11.67 µg/ml) followed by ethyl acetate fraction 54.97% (IC50, 15.89 µg/ml), crude extract 46.79% (IC50, >16.5 µg/ml), and chloroform fraction 36.44% (IC50, >16.5 µg/ml). In the antioxidant assay, the crude extract exhibited the highest antioxidant activity 86.36% (IC50, 10.25 µg/ml) followed by water fraction 78.59% (IC50, 13.86 µg/ml), ethyl acetate fraction 71.58% (IC50, 16.34 µg/ml), and chloroform fraction 63.65% (IC50, 18.83 µg/ml). Conclusion: This study has revealed that H. abyssinica leaves possess noticeable in vitro α-amylase and α-glucosidase inhibitory and antioxidant activities.


Assuntos
Antioxidantes/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Extratos Vegetais , Rosaceae/química , alfa-Amilases/antagonistas & inibidores , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Solventes/química , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo
6.
Food Chem ; 358: 129837, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33940299

RESUMO

There is evidence that moderate coffee consumption is beneficial in the prevention of type 2 diabetes, however, the underlying mechanism is not understood. In this study, the effects of an extract of ground coffee on the in vitro enzymatic digestion of starch were investigated. The coffee extract decreased the rate and extent of starch digestion, with kinetic analysis showing that the extract reduced the binding affinity of the enzymes for the substrate and their catalytic turnover. Fluorescence quenching indicated that the coffee extract formed complexes with the digestive enzymes through a static quenching mechanism. Ultraviolet absorption and circular dichroism spectra of the digestive enzymes confirmed that the coffee extract decreased the proportion of ß-sheet structures in the enzymes. Therefore, we conclude that compounds in the soluble coffee extract can interact with porcine pancreatic amylase and amyloglucosidase causing inhibition of the enzymes and decreasing in vitro starch digestion.


Assuntos
Café , Glucana 1,4-alfa-Glucosidase/antagonistas & inibidores , Extratos Vegetais/farmacologia , Amido/metabolismo , alfa-Amilases/antagonistas & inibidores , Animais , Digestão , Glucana 1,4-alfa-Glucosidase/metabolismo , Hidrólise , Cinética , Suínos/metabolismo , alfa-Amilases/metabolismo
7.
Molecules ; 26(7)2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33808152

RESUMO

Numerous scientific studies have confirmed the beneficial therapeutic effects of phenolic acids. Among them gentisic acid (GA), a phenolic acid extensively found in many fruit and vegetables has been associated with an enormous confirmed health benefit. The present study aims to evaluate the antidiabetic potential of gentisic acid and highlight its mechanisms of action following in silico and in vitro approaches. The in silico study was intended to predict the interaction of GA with eight different receptors highly involved in the management and complications of diabetes (dipeptidyl-peptidase 4 (DPP4), protein tyrosine phosphatase 1B (PTP1B), free fatty acid receptor 1 (FFAR1), aldose reductase (AldR), glycogen phosphorylase (GP), α-amylase, peroxisome proliferator-activated receptor gamma (PPAR-γ) and α-glucosidase), while the in vitro study studied the potential inhibitory effect of GA against α-amylase and α-glucosidase. The results indicate that GA interacted moderately with most of the receptors and had a moderate inhibitory activity during the in vitro tests. The study therefore encourages further in vivo studies to confirm the given results.


Assuntos
Frutas/química , Gentisatos/metabolismo , Inibidores de Glicosídeo Hidrolases/metabolismo , Hipoglicemiantes/metabolismo , alfa-Amilases , alfa-Glucosidases/metabolismo , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
8.
J Biosci Bioeng ; 131(6): 605-612, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33814275

RESUMO

The structures of Aspergillus oryzae α-amylase were determined in a tetragonal crystal, having one molecule as asymmetric unit, and a monoclinic crystal with two molecules as asymmetric unit. Both crystal forms were obtained from trace contaminants of an old commercial lipase preparation. Structures were determined and refined to 1.65 Å and 1.43 Å resolution respectively. The latter crystal has a non-crystallographic (NCS) twofold axis within the asymmetric unit. Glycosylation at Asn197 is evident, and in the tetragonal crystal can be seen to include three, partially disordered sugar residues following the initial N-acetyl glucosamine (NAG). Superposition of the tetragonal crystal model on the α-amylases from Bacillus subtilis (PDB:1BAG), pig pancreas (PDB:3L2L), and barley (PDB:1AMY), show a high degree of coincidence, particularly for the (ß/α)8-barrel domains, and especially within the active site. Using this structural agreement between amylases, we extrapolated the binding model of a six residue, limit dextrin found in pig pancreas α-amylase to the A. oryzae enzyme model, which predicts substrate interacting amino acid residues.


Assuntos
Aspergillus oryzae/enzimologia , alfa-Amilases/química , Amilases/metabolismo , Animais , Aspergillus oryzae/metabolismo , Bacillus subtilis/enzimologia , Sítios de Ligação , Cristalografia por Raios X , Hordeum/enzimologia , Isoenzimas/química , Isoenzimas/metabolismo , Modelos Moleculares , alfa-Amilases Pancreáticas/química , Conformação Proteica , Estrutura Terciária de Proteína , Suínos/metabolismo , alfa-Amilases/metabolismo
9.
J Food Sci ; 86(5): 1726-1736, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33844283

RESUMO

In this work, red quinoa was successively subjected to α-amylase steaming, complex enzyme Viscozyme (R) L hydrolysis, and lactic acid bacteria (LAB) fermentation. The total phenolic compound content (TPC), flavonoid content (TFC), and antioxidant capacities of the solvent-extractable (free) and bound fractions and the individual phenolic compounds released were determined. Compared to steaming with α-amylase, enzymatic hydrolysis and fermentation of quinoa resulted in approximately 82.6, 26.9, 36.3, and 45.2% increases in the TPC (the sum of free and bound fractions), TFC, DPPH, and ORAC values, respectively. HPLC-QqQ-MS/MS analysis showed that enzymolysis and fermentation increased the content of protocatechuic acid, catechin, procyanidin B2 , and quercetin by 126.3, 101.9, 524, and 296.3%, respectively. Moreover, a major proportion of individual phenolic compounds existed as bound form. The results indicated that complex enzymatic hydrolysis and LAB fermentation were practical and useful to release promising polyphenols. This research provides a basis for the processing of quinoa beverages rich in phenolic compounds. PRACTICAL APPLICATION: In this work, liquefying with α-amylase, hydrolyzing with cellulolytic enzyme mixture, and fermenting with Lactic acid bacteria (LAB), successively, were exploited to process quinoa. This is an innovative method of quinoa processing to produce beverage products. Complex enzymatic hydrolysis and fermentation with LAB can significantly enhance phenolic compound, especially protocatechuic acid, catechin, procyanidin B2 , and quercetin. In additional, LAB fermentation is very beneficial to improve the antioxidant activity of quinoa. We also found that a major proportion of phenolic compounds existed as bound forms in quinoa.


Assuntos
Antioxidantes/análise , Chenopodium quinoa/metabolismo , Manipulação de Alimentos/métodos , Lactobacillus/metabolismo , Complexos Multienzimáticos/metabolismo , Fenóis/análise , Chenopodium quinoa/química , Fermentação , Flavonoides/análise , Hidrólise , Hidroxibenzoatos/análise , Soluções , Vapor , Água , alfa-Amilases/metabolismo
10.
Molecules ; 26(9)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922645

RESUMO

Kinkor (Ferulago stellata) is Turkish medicinal plant species and used in folk medicine against some diseases. As far as we know, the data are not available on the biological activities and chemical composition of this medicinal plant. In this study, the phytochemical composition; some metabolic enzyme inhibition; and antidiabetic, anticholinergic, and antioxidant activities of this plant were assessed. In order to evaluate the antioxidant activity of evaporated ethanolic extract (EEFS) and lyophilized water extract (WEFS) of kinkor (Ferulago stellata), some putative antioxidant methods such as DPPH· scavenging activity, ABTS•+ scavenging activity, ferric ions (Fe3+) reduction method, cupric ions (Cu2+) reducing capacity, and ferrous ions (Fe2+)-binding activities were separately performed. Furthermore, ascorbic acid, BHT, and α-tocopherol were used as the standard compounds. Additionally, the main phenolic compounds that are responsible for antioxidant abilities of ethanol and water extracts of kinkor (Ferulago stellata) were determined by liquid chromatography-high-resolution mass spectrometry (LC-HRMS). Ethanol and water extracts of kinkor (Ferulago stellata) demonstrated effective antioxidant abilities when compared to standards. Moreover, ethanol extract of kinkor (Ferulago stellata) demonstrated IC50 values of 1.772 µg/mL against acetylcholinesterase (AChE), 33.56 ± 2.96 µg/mL against α-glycosidase, and 0.639 µg/mL against α-amylase enzyme respectively.


Assuntos
Antioxidantes/química , Apiaceae/química , Antagonistas Colinérgicos/química , Cromatografia Líquida/métodos , Hipoglicemiantes/química , Componentes Aéreos da Planta/química , Plantas Medicinais/química , alfa-Amilases/metabolismo
11.
Mar Drugs ; 19(3)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808933

RESUMO

In this work, a non-toxic chitosan-based carrier was constructed via genipin activation and applied for the immobilization of tannase. The immobilization carriers and immobilized tannase were characterized using Fourier transform infrared spectroscopy and thermogravimetric analysis. Activation conditions (genipin concentration, activation temperature, activation pH and activation time) and immobilizations conditions (enzyme amount, immobilization time, immobilization temperature, immobilization pH, and shaking speed) were optimized. The activity and activity recovery rate of the immobilized tannase prepared using optimal activation and immobilization conditions reached 29.2 U/g and 53.6%, respectively. The immobilized tannase exhibited better environmental adaptability and stability. The immobilized tannase retained 20.1% of the initial activity after 12 cycles and retained 81.12% of residual activity after 30 days storage. The catechins composition analysis of tea extract indicated that the concentration of non-ester-type catechins, EGC and EC, were increased by 1758% and 807% after enzymatic treatment. Biological activity studies of tea extract revealed that tea extract treated with the immobilized tannase possessed higher antioxidant activity, higher inhibitory effect on α-amylase, and lower inhibitory effect on α-glucosidase. Our results demonstrate that chitosan activated with genipin could be an effective non-toxic carrier for tannase immobilization and enhancing biological activities of tea extract.


Assuntos
Antioxidantes/farmacologia , Camellia sinensis , Hidrolases de Éster Carboxílico/metabolismo , Quitosana/química , Portadores de Fármacos , Inibidores de Glicosídeo Hidrolases/farmacologia , Iridoides/química , Extratos Vegetais/farmacologia , alfa-Amilases/antagonistas & inibidores , Antioxidantes/isolamento & purificação , Antioxidantes/metabolismo , Camellia sinensis/metabolismo , Hidrolases de Éster Carboxílico/química , Composição de Medicamentos , Estabilidade Enzimática , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Temperatura , Fatores de Tempo , alfa-Amilases/metabolismo
12.
Molecules ; 26(8)2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33918091

RESUMO

The aim of the study was to investigate the micromorphology of Mentha pulegium leaves and flowers harvested in three different Sicilian (Italy) areas with peculiar pedo-climatic conditions, and to characterize the phytochemical profile, the phytotoxic activity, and the eco-compatibility of their essential oils (EOs) for potential use as safe bioherbicides. Light microscopy (LM) and scanning electron microscopy (SEM) highlighted that M. pulegium indumentum consists of non-glandular and glandular trichomes of different types. Peltate trichomes of plants from the different sites showed few significant differences in dimension and abundance, but they were characterized by a surprisingly high number of secretory cells both in leaves and flowers. Phytochemical analyses showed that oxygenated monoterpenes were the most abundant class in all the EOs investigated (92.2-97.7%), but two different chemotypes, pulegone/isomenthone and piperitone/isomenthone, were found. The complex of morphological and phytochemical data indicates that soil salinity strongly affects the expression of the toxic metabolite pulegone, rather than the EO yield. Phytotoxicity tests showed a moderate activity of EOs against the selected species as confirmed by α-amylase assay. Moreover, the low toxicity on brine shrimp provided a rationale for the possible use of investigated EOs as eco-friendly herbicides.


Assuntos
Economia , Mentha pulegium/química , Animais , Artemia , Flores/anatomia & histologia , Flores/ultraestrutura , Geografia , Itália , Mentha pulegium/anatomia & histologia , Mentha pulegium/ultraestrutura , Óleos Voláteis/análise , Óleos Voláteis/economia , Compostos Fitoquímicos/toxicidade , Folhas de Planta/anatomia & histologia , Folhas de Planta/ultraestrutura , Sus scrofa , Testes de Toxicidade , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
13.
Molecules ; 26(7)2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33918380

RESUMO

Silk proteins have many advantageous components including proteins and pigments. The proteins-sericin and fibroin-have been widely studied for medical applications due to their good physiochemical properties and biological activities. Various strains of cocoon display different compositions such as amino-acid profiles and levels of antioxidant activity. Therefore, the objectives of this study were to find a suitable silk protein extraction method to obtain products with chemical and biological properties suitable as functional foods in two strains of Bombyx mori silk cocoon (Nangsew strains; yellow cocoon) and Samia ricini silk cocoon (Eri strains; white cocoon) extracted by water at 100 °C for 2, 4, 6 and 8 h. The results showed that Nangsew strains extracted for 6 h contained the highest amounts of protein, amino acids, total phenolics (TPC) and total flavonoids (TFC), plus DPPH radical-scavenging activity, ABTS radical scavenging capacity, and ferric reducing antioxidant power (FRAP), anti-glycation, α-amylase and α-glucosidase inhibition. The longer extraction time produced higher concentrations of amino acids, contributing to sweet and umami tastes in both silk strains. It seemed that the bitterness decreased as the extraction time increased, resulting in improvements in the sweetness and umami of silk-protein extracts.


Assuntos
Aminoácidos/análise , Seda/química , Água/química , Benzotiazóis/química , Compostos de Bifenilo/química , Flavonoides/análise , Sequestradores de Radicais Livres/química , Produtos Finais de Glicação Avançada/metabolismo , Inibidores de Glicosídeo Hidrolases/farmacologia , Oxirredução , Fenóis/análise , Picratos/química , Ácidos Sulfônicos/química , Tailândia , Fatores de Tempo , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
14.
Chem Biodivers ; 18(4): e2000999, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33738900

RESUMO

Toddalia asiatica (L.) Lam. is extensively used in traditional medicinal systems by various cultures. Despite its frequent use in traditional medicine, there is still a paucity of scientific information on T. asiatica growing on the tropical island of Mauritius. Therefore, the present study was designed to appraise the pharmacological and phytochemical profile of extracts (methanol, ethyl acetate and water) and essential oil obtained from aerial parts of T. asiatica. Biological investigation involved the evaluation of in vitro antioxidant and enzyme inhibitory potentials. The chemical profile of the EO was determined using gas chromatography coupled to mass spectrometry (GC/MS) analysis, while for the extracts, the total phenolic (TPC) and flavonoid content were quantified as well as their individual phenolic compounds by LC/MS/MS. Quinic acid, fumaric acid, chlorogenic acid, quercitrin and isoquercitrin were the main compounds in the extracts. Highest total phenolic (82.5±0.94 mg gallic acid equivalent (GAE/g)) and flavonoid (43.8±0.31 mg rutin equivalent (RE/g)) content were observed for the methanol extract. The GC/MS analysis has shown the presence of 26 compounds with linalool (30.9 %), linalyl acetate (20.9 %) and ß-phellandrene (7.9 %) being most abundant components in the EO. The extracts and EO showed notable antioxidant properties, with the methanol extract proved to be superior source of antioxidant compounds. Noteworthy anti-acetylcholinesterase (AChE) and anti-butyrylcholinesterase (BChE) effects were recorded for the tested samples, while only the methanol and ethyl acetate extracts were active against tyrosinase. With respect to antidiabetic effects, the extracts and EO were potent inhibitors of α-glucosidase, while modest activity was recorded against α-amylase. Docking results showed that linalyl acetate has the highest affinity to interact with the active site of BChE with docking score of -6.25 kcal/mol. The findings amassed herein act as a stimulus for further investigations of this plant as a potential source of bioactive compounds which can be exploited as phyto-therapeutics.


Assuntos
Antioxidantes/farmacologia , Inibidores Enzimáticos/farmacologia , Óleos Voláteis/farmacologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Rutaceae/química , Acetilcolinesterase/metabolismo , Animais , Antioxidantes/química , Antioxidantes/isolamento & purificação , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Butirilcolinesterase/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Humanos , Medicina Tradicional , Modelos Moleculares , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Estresse Oxidativo/efeitos dos fármacos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Picratos/antagonistas & inibidores , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais/química , Espécies Reativas de Oxigênio/metabolismo , Ácidos Sulfônicos/antagonistas & inibidores , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo
15.
Carbohydr Polym ; 260: 117801, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33712149

RESUMO

Slowly digestible starches have received interest due to their lower increase of postprandial blood glucose and insulin levels and, hence, modification of starches towards slower digestibility has commercial interest. However, chemical characteristics driving enzymatic (digestive) degradation are not fully unraveled. The digestion properties of starches have been linked to their crystalline type, chain length distribution, amylose content or degree of branching, but content and length of relatively long side-chains in amylopectin has not been paid attention to. Therefore, this research focusses on the unique content and length of amylopectin side-chains from conventional and new starch sources (potato, corn, pea, and tulip) correlated to the enzymatic digestion. The rate of hydrolysis was found to be correlated with the crystalline type of starch, as previously suggested, however, the complete hydrolysis of all starches, independent of the crystalline type and source, was shown to be governed by the content of longer amylopectin chains.


Assuntos
Gelatina/química , Glucana 1,4-alfa-Glucosidase/metabolismo , Amido/metabolismo , alfa-Amilases/metabolismo , Cristalização , Digestão , Hidrólise , Espectroscopia de Ressonância Magnética , Ervilhas/metabolismo , Solanum tuberosum/metabolismo , Amido/química , Zea mays/metabolismo
16.
Food Chem ; 353: 129374, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33740505

RESUMO

Camel milk proteins are an important substrate for bioactive peptides generation. This study investigates in-vitro antidiabetic effect (via inhibition of α-amylase (AA), α-glucosidase (AG) and dipeptidyl peptidase IV (DPP-IV)) of bovine (BC) and camel casein (CC) hydrolysates. Further, effect of simulated gastrointestinal digestion (SGID) on inhibitory potential of generated hydrolysates was also explored. Both BC and CC hydrolysates displayed potent inhibitory properties against AA (IC50 value- 0.58 & 0.59 mg/mL), AG (IC50 value- 1.04 & 0.59 mg/mL) and DPP-IV (IC50 value- 0.62 & 0.66 mg/mL), respectively. Among different peptides identified in BC and CC hydrolysates, it was observed that FLWPEYGAL was predicted to be most potent inhibitory peptide against AA. While LPTGWLM, MFE and GPAHCLL as most active inhibitor of AG and HLPGRG, QNVLPLH and PLMLP were predicted to be active against DPP-IV. Overall, BC and CC hydrolysates can be proposed to be used in different food formulations as functional antidiabetic agents.


Assuntos
Caseínas/metabolismo , Digestão/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Sequência de Aminoácidos , Animais , Camelus , Caseínas/química , Bovinos , Inibidores da Dipeptidil Peptidase IV/farmacologia , Proteínas do Leite/química , Peptídeos/química , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo
17.
Carbohydr Polym ; 259: 117738, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33674022

RESUMO

Starch is present in many prepared 'ready-meals' that have undergone processing and/or storage in frozen or chilled state. Hydrothermal processing greatly increases starch digestibility and postprandial glycaemia. Effects of different heating/drying and cooling regimes on amylolysis have received little attention. Hence, we examined the effects of different processing treatments on in vitro digestibility of starch in chickpea flour. Solid-state 13C NMR was used to estimate ordered double-helical structure in the starch. Native starch with 25 % double-helical content was the most resistant to digestion but hydrothermal processing (gelatinisation) resulted in >95 % loss of order and a large increase in starch digestibility. Air-drying of pre-treated flour produced slowly-digestible starch (C∞, 55.9 %). Refrigeration of gelatinised samples decreased ease of amylolysis coincident with increase in double-helical content. Freezing maintained the same degree of digestibility as freshly gelatinised material and produced negligible retrogradation. Chilling may be exploited to produce ready-meals with a lower glycaemic response.


Assuntos
Cicer/metabolismo , Farinha/análise , Amido/metabolismo , alfa-Amilases/metabolismo , Dessecação , Digestão , Armazenamento de Alimentos , Cinética , Espectroscopia de Ressonância Magnética , Amido/química
18.
Food Chem ; 355: 129414, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33773461

RESUMO

A screening of inhibitory activity of α-amylase, as well as pancreatic lipase (PL), under the influence of aqueous and ethanolic preparations from 12 plant materials was performed. The most active aqueous extracts from the fruits of Chaenomeles japonica (CJ) and Hippophaë rhamnoides (HR) were selected for artificial gastrointestinal digestion (GID). The aim of this study was to evaluate the inhibitory effect of the fractions obtained after GID on PL and α-amylase activities using a fluorescence assay. The changes in the composition of crude extracts in GID aliquots were followed by analysis with HPLC-DAD-MSn method in order to indicate active constituents. The main constituents of CJ and HR extracts were procyanidins and isorhamnetin derivatives, respectively. The most abundant compounds of extracts were found in all compartments of the digestion model correlated with relevant lipase/α-amylase inhibitory activity. What is more, the gastric and intestinal fractions inhibited enzymatic activity by at least 40%.


Assuntos
Hippophae/química , Lipase/antagonistas & inibidores , Extratos Vegetais/química , Rosaceae/química , alfa-Amilases/antagonistas & inibidores , Cromatografia Líquida de Alta Pressão , Digestão , Frutas/química , Frutas/metabolismo , Hippophae/metabolismo , Humanos , Lipase/metabolismo , Espectrometria de Massas , Extratos Vegetais/análise , Extratos Vegetais/metabolismo , Proantocianidinas/análise , Proantocianidinas/química , Proantocianidinas/metabolismo , Rosaceae/metabolismo , alfa-Amilases/metabolismo
19.
Molecules ; 26(4)2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33669312

RESUMO

Diabetes mellitus is a chronic disease and one of the fastest-growing health challenges of the last decades. Studies have shown that chronic low-grade inflammation and activation of the innate immune system are intimately involved in type 2 diabetes pathogenesis. Momordica charantia L. fruits are used in traditional medicine to manage diabetes. Herein, we report the purification of a new 23-O-ß-d-allopyranosyl-5ß,19-epoxycucurbitane-6,24-diene triterpene (charantoside XV, 6) along with 25ξ-isopropenylchole-5(6)-ene-3-O-ß-d-glucopyranoside (1), karaviloside VI (2), karaviloside VIII (3), momordicoside L (4), momordicoside A (5) and kuguaglycoside C (7) from an Indian cultivar of Momordica charantia. At 50 µM compounds, 2-6 differentially affected the expression of pro-inflammatory markers IL-6, TNF-α, and iNOS, and mitochondrial marker COX-2. Compounds tested for the inhibition of α-amylase and α-glucosidase enzymes at 0.87 mM and 1.33 mM, respectively. Compounds showed similar α-amylase inhibitory activity than acarbose (0.13 mM) of control (68.0-76.6%). Karaviloside VIII (56.5%) was the most active compound in the α-glucosidase assay, followed by karaviloside VI (40.3%), while momordicoside L (23.7%), A (33.5%), and charantoside XV (23.9%) were the least active compounds. To better understand the mode of binding of cucurbitane-triterpenes to these enzymes, in silico docking of the isolated compounds was evaluated with α-amylase and α-glucosidase.


Assuntos
Anti-Inflamatórios/farmacologia , Simulação por Computador , Frutas/química , Glicosídeos/química , Glicosídeos/farmacologia , Hipoglicemiantes/farmacologia , Momordica charantia/química , Triterpenos/química , Triterpenos/farmacologia , Animais , Anti-Inflamatórios/química , Bioensaio , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Glicosídeos/isolamento & purificação , Hipoglicemiantes/química , Ligantes , Camundongos , Conformação Molecular , Simulação de Acoplamento Molecular , Espectroscopia de Prótons por Ressonância Magnética , Células RAW 264.7 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Triterpenos/isolamento & purificação , alfa-Amilases/química , alfa-Amilases/metabolismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
20.
Food Chem ; 352: 129307, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33691209

RESUMO

Development of gluten-free products is important due to their role in gluten related disorders and health improvement. α-Amylase enzymes have shown to have a positive effect on wheat bread quality. This study aimed to screen in-silico a novel acidic-thermostable α-amylase (PersiAmy2) from the sheep rumen metagenome to increase the quality of gluten-free bread. The PersiAmy2 was cloned, expressed, purified and characterized. The enzyme was highly stable at a wide range of pH, temperature and storage conditions. The PersiAmy2 had excellent activity in the presence of ions, inhibitors, and surfactants. Utilization of the acidic thermostable PersiAmy2 in gluten-free bread resulted in a softer crumb, higher specific volume, porosity, moisture content and caused a darker crust color. The rheological measurement showed a solid-elastic behavior in batters. Also the addition of this enzyme reduced the firmness. From the results of this study it can be concluded that the PersiAmy2 can be used to improve the quality of gluten-free bread.


Assuntos
Pão/análise , Dieta Livre de Glúten , Metagenômica , Temperatura , alfa-Amilases/metabolismo , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Reologia , Triticum/química , Triticum/metabolismo
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