Showing papers on "Amylase published in 2018"
TL;DR: These molecules can be elective inhibitors of GST, α-glycosidase and α-amylase enzymes as antidiabetic and antiparasitic agents and demonstrate effective inhibitor compounds with Ki values in the range of 8.34-40.78 μM against GST, and 120.53-892.36 nM against α- Glycosid enzyme.
158 citations
TL;DR: In this study, aldose reductase was purified from purified from cow liver, and compounds were tested for their inhibition effects against of α-glycosidase enzyme and demonstrated efficient inhibition profiles with Ki values in the range of 14.44 ± 0.06 nM, and IC50 values inThe range of 11.72-46.61’nM.
153 citations
TL;DR: The results indicated that UIOPS-1 still exhibited antioxidant and antihyperglycemic potential after gastrointestinal digestion, which could be considered as a promising candidate for functional foods.
113 citations
TL;DR: The mechanisms whereby interactions of protein and starch in barley flour affect the kinetics of enzymatic hydrolysis of starch in an in vitro system are explored, using digestion rate data and structural analysis by confocal microscopy.
109 citations
TL;DR: It was considered that Lactobacillus sp G3_4_1TO2 was a potential probiotic bacteria producing maximum amylase enzyme.
108 citations
TL;DR: Germinated soybean protein showed a promising potential to be used as a nutraceutical or functional ingredient for diabetes prevention and the analysis of structural features of peptides in F1–F3 allowed the tentative identification of potential antidiabetic peptides.
Abstract: Functional foods containing peptides offer the possibility to modulate the absorption of sugars and insulin levels to prevent diabetes. This study investigates the potential of germinated soybean peptides to modulate postprandial glycaemic response through inhibition of dipeptidyl peptidase IV (DPP-IV), salivary α-amylase, and intestinal α-glucosidases. A protein isolate from soybean sprouts was digested by pepsin and pancreatin. Protein digest and peptide fractions obtained by ultrafiltration ( 10 kDa) and subsequent semipreparative reverse phase liquid chromatography (F1, F2, F3, and F4) were screened for in vitro inhibition of DPP-IV, α-amylase, maltase, and sucrase activities. Protein digest inhibited DPP-IV (IC50 = 1.49 mg/mL), α-amylase (IC50 = 1.70 mg/mL), maltase, and sucrase activities of α-glucosidases (IC50 = 3.73 and 2.90 mg/mL, respectively). Peptides of 5–10 and >10 kDa were more effective at inhibiting DPP-IV (IC50 = 0.91 and 1.18 mg/mL, respectively), while peptides of 5–10 and <5 kDa showed a higher potency to inhibit α-amylase and α-glucosidases. Peptides in F1, F2, and F3 were mainly fragments from β-conglycinin, glycinin, and P34 thiol protease. The analysis of structural features of peptides in F1–F3 allowed the tentative identification of potential antidiabetic peptides. Germinated soybean protein showed a promising potential to be used as a nutraceutical or functional ingredient for diabetes prevention.
94 citations
TL;DR: α-amylase inhibitory peptides were identified from proteolytic enzymes hydrolysates of red seaweed laver using consecutive chromatographic techniques and revealed that these peptides exhibited noncompetitive binding mode, suggesting laver can be a potential source of novel ingredients in food and pharmaceuticals in diabetes mellitus management.
Abstract: Inhibition of α-amylase enzyme is one therapeutic approach in lowering glucose level in the blood to manage diabetes mellitus. In this study α-amylase inhibitory peptides were identified from proteolytic enzymes hydrolysates of red seaweed laver (Porphyra species) using consecutive chromatographic techniques. In the resultant fractions from RP-HPLC (D1-10), D2 inhibited α-amylase activity (88.67 ± 1.05%) significantly (p ≤ 0.5) at 1 mg/mL protein concentration. A mass spectrometry (ESI-Q-TOF- MS) analysis was used to identify peptides from this fraction. Two novel peptides were identified as Gly-Gly-Ser-Lys and Glu-Leu-Ser. To validate their α-amylase inhibitory activity, these peptides were synthesized chemically. The peptides were demonstrated inhibitory activity at IC50 value: 2.58 ± 0.08 mM (Gly-Gly-Ser-Lys) and 2.62 ± 0.05 mM (Glu-Leu-Ser). The inhibitory kinetics revealed that these peptides exhibited noncompetitive binding mode. Thus, laver can be a potential source of novel ingredients in food and...
89 citations
TL;DR: It is observed that the amylolytic activity of saliva plays a preponderant role hydrolysing up to 80% of bread starch in the first 30 min of gastric digestion, revealing its high efficiency.
Abstract: The role of salivary α-amylase (HSA) in starch digestion is often overlooked in favour of that of pancreatic α-amylase due to the short duration of the oral phase. Although it is generally accepted that the amylase of salivary origin can continue to be active in the stomach, studies ascertaining its contribution are lacking. This study aimed to address this issue by coupling in vitro oral processing with an in vitro dynamic system that mimicked different postprandial gastric pH reduction kinetics observed in vivo following a snack- or lunch-type meal. The digestion of both starch and protein from wheat bread as well as the interplay between the two processes were studied. We have observed that the amylolytic activity of saliva plays a preponderant role hydrolysing up to 80% of bread starch in the first 30 min of gastric digestion. Amylolysis evolved exponentially and nearly superimposing curves were obtained regardless of the acidification profiles, revealing its high efficiency.
85 citations
TL;DR: Starch hydrolytic activity of combi-MOF was tested for different sources of starch which exhibited higher rate of hydrolysis than mixture of free enzymes due to spatially co-localized multi-enzymatic systems.
83 citations
TL;DR: This review mainly deals with the inhibition of α-amylase activity by flavonoids suggesting the mechanisms of the inhibition, suppression of starch digestion by Flavonoids by forming starch-flavonoid complexes by hydrophobic interactions, and formation of starch not easily digested by α- amylase by the formation of covalent bonds between flavonoid and starch during cooking and in the stomach.
Abstract: Starch is digested to glucose in the intestine and absorbed into the body. If the increased blood concentrations of sugar after meals decrease slowly or are maintained for a long time, various adverse effects are induced. Therefore, it is important to decrease the rate of the digestibility of starch in the intestine in the patients of hyperglycemia. One of the ways to effect a decrease is the inhibition of α-amylase secreted from the pancreas. Flavonoids are a group of compounds that can inhibit this enzyme's activity, and many investigators have studied the flavonoid-dependent inhibition of this enzyme and presented mechanisms for the inhibition of its activity. Starch containing foods, however, cooked or ingested with flavonoid containing foods are mixed with saliva and gastric juice in the stomach. Thus, flavonoids in the foods can interact with starch and can react with nitrous acid derived from the oral cavity in the stomach before being transported to the intestine. This review mainly deals with: (i) the inhibition of α-amylase activity by flavonoids suggesting the mechanisms of the inhibition, (ii) suppression of starch digestion by flavonoids by forming starch-flavonoid complexes by hydrophobic interactions, and (iii) formation of starch not easily digested by α-amylase by the formation of covalent bonds between flavonoids and starch during cooking and in the stomach. In addition, the cooperation of flavonoids with fatty acids are discussed taking their binding to amylose into account.
80 citations
TL;DR: It was proven that cell structural changes, if any, occurring during digestion had no effect on starch hydrolysis and it was concluded that cell wall serves as a permeable barrier limiting the access of digestive enzymes.
TL;DR: Results indicated that 1:1 ratio of pre and post consumed food wastes (FWs) were helpful to facilitate the degradation employing bacterial consortium, and organic matter decomposition and chemical parameters of the end product quality indicated that bacterial consortium was very effective for 1: 1 ratio of FWs degradation as compared to the other treatments.
TL;DR: It is suggested that persimmon tannin may alleviate postprandial hyperglycemia through limiting the digestion of starch as well as inhibiting the uptake and transport of glucose.
Abstract: Regulation of postprandial blood glucose levels is an effective therapeutic proposal for type 2 diabetes treatment In this study, the effect of persimmon tannin on starch digestion with different amylose levels was investigated both in vitro and in vivo Oral administration of persimmon tannin–starch complexes significantly suppressed the increase of blood glucose levels and the area under the curve (AUC) in a dose-dependent manner compared with starch treatment alone in an in vivo rat model Further study proved that persimmon tannin could not only interact with starch directly but also inhibit α-amylase and α-glucosidase strongly, with IC50 values of 035 and 024 mg/mL, separately In addition, 20 μg/mL of persimmon tannin significantly decreased glucose uptake and transport in Caco-2 cells model Overall, our data suggested that persimmon tannin may alleviate postprandial hyperglycemia through limiting the digestion of starch as well as inhibiting the uptake and transport of glucose
TL;DR: In this article, intact cells were isolated from dry milled flour obtained using three grinding rolls coupled with a wet sieving technique using selected sieves having varying apertures to investigate the effect of intactness of cell walls on enzymic hydrolysis of entrapped starch.
TL;DR: High thermostability, Ca2+-independency, broad temperature and pH profiles, organic-solvent tolerance as well as excellent stability with detergents, and the α-amylase will be a suitable candidate in industrial fields are presented.
TL;DR: The present study suggests the applicability of palm oil addition during the rice cooking to enhance its nutritional functionality, by reducing the in vitro starch digestibility and enhancing the resistance starch content whilst decreasing the rapid and slow digestion fractions of non-waxy varieties.
TL;DR: These three probiotic Bacillus strains showed beneficial effects on chickens with minor strain specificity and markedly improved final body weight, daily weight gain, and the activities of trypsin, amylase, lipase and total protease.
Abstract: This study was conducted to evaluate the effects of three Bacillus strains on growth performance, digestive enzyme activities, antioxidative capacity, serum immunity, and biochemical parameters in broilers A total of 360 one-day-old Ross 308 chicks were randomly allocated into four groups with three replicates per group (n = 30) The control group was fed a basal diet, whereas the other groups fed basal diet supplemented with either Bacillus subtilis natto or Bacillus licheniformis or Bacillus cereus (108 cfu/kg) for 42 days, respectively The results revealed that the probiotic-treated groups markedly improved final body weight, daily weight gain, and the activities of trypsin, amylase, lipase and total protease (p < 005) Moreover, chicks fed probiotics had higher serum glutathione peroxidase activity and O2 - level, as well as hepatic catalase and superoxide dismutase activities, whereas malondialdehyde levels in serum and liver were reduced (p < 005) The significant increased IgA (p < 005) was observed in the probiotics groups as compared to the control group In addition, dietary administration of probiotic strain markedly reduced the levels of serum ammonia, uric acid, total cholesterol, and triglyceride Taken together, these three probiotic Bacillus showed beneficial effects on chickens with minor strain specificity
TL;DR: This study investigated the influence of spherical and polygonal starch nanoparticles (SNPs) on α-amylase activity and revealed the reaction mechanisms by ultraviolet-visible spectrophotometry, fluorescence spectroscopy, and circular dichroism (CD) spectroscopic.
Abstract: Nanoparticles are novel and fascinating materials for tuning the activities of enzymes. In this study, we investigated the influence of spherical and polygonal starch nanoparticles (SNPs) on α-amylase activity and revealed the reaction mechanisms by ultraviolet-visible spectrophotometry, fluorescence spectroscopy, and circular dichroism (CD) spectroscopy. We discovered that both spherical and polygonal SNPs could inhibit the α-amylase activity, with half-inhibitory concentration values of 0.304 and 0.019 mg mL-1, respectively. Furthermore, spherical and polygonal SNPs followed competitive and mixed competitive inhibition mechanisms, respectively. The fluorescence data indicated that static quenching was dominant in the interaction between SNPs and α-amylase. The CD results demonstrated that the inhibition of α-amylase by SNPs was accompanied by the decreased intensity of the CD spectra of α-amylase. Our findings provide a novel strategy to inhibit α-amylase to reduce the digestion of starch, thus managing blood glucose levels.
TL;DR: By incorporating CNCs into maize, potato and pea starches, the contents of rapid digestible starch and slowly digestable starch of the cooked starches decreased while resistant starch content increased.
TL;DR: Wash performance analysis revealed that the SA crude enzymes exhibited a remarkable efficiency in the removal of a variety of stains, such as blood, chocolate, coffee and oil, and could be used in several biotechnological bioprocesses.
TL;DR: Findings suggested that marine bacterial derived amylase enzyme could be developed as potential antibiofilm agent.
TL;DR: It is demonstrated that the cell wall anchored starch‐degrading α‐amylase, Amy13K of E. rectale harbors five CBMs that all target starch with differing specificities, which provides a molecular rationale for why the organism is able to only use certain starch types without the aid of other organisms.
Abstract: Gut bacteria recognize accessible glycan substrates within a complex environment. Carbohydrate binding modules (CBMs) of cell-surface glycoside hydrolases often drive binding to the target substrate. Eubacterium rectale, an important butyrate-producing organism in the gut, consumes a limited rangeof substrates, including starch. Host consumption of resistant starch increases the abundance of E. rectale in the intestine, likely because it successfully captures the products of resistant starch degradation by other bacteria. Here we demonstrate that the cell wall anchored starch-degrading α-amylase, Amy13K of E. rectale harbors five CBMs that all target starch with differing specificities. Intriguingly these CBMs efficiently bind to both regular and high amylose corn starch (a type of resistant starch), but have almost no affinity for potato starch (another type of resistant starch). Removal of these CBMs from Amy13K reduces the activity level of the enzyme towards corn starches by ~40-fold, down to the level of activity towards potato starch, suggesting that the CBMs facilitate activity on corn starch and allowing its utilization in vivo. The specificity of the Amy13K CBMs provides a molecular rationale for why E. rectale is able to only use certain starch types without the aid of other organisms.
TL;DR: Tea products, such as tea polyphenols (TP), epigallocatechin gallate (EGCG), matcha, and instant tea, were chosen as constituents of tea-flour food, aimed at regulating the release of glucose from starchy foods in the postprandial period to get a desired formulation of dietary product for patients with hyperglycemia.
TL;DR: This research presents a concept for oral release food emulsions with destabilisation via salivary amylase digestion of the stabilising starch emulsifier, providing the food industry with exciting results for the formulation of clean label emulsion.
TL;DR: The purified α-amylase was stable in the presence of detergents, organic solvents and Proteinase K, and exhibited the ability to hydrolyze raw starches efficiently; thus this enzyme has the potential to be used for industrial applications.
TL;DR: The effects of tea polyphenols on binding of porcine pancreatic α-amylase (PPA) with normal maize starch granules were studied through solution depletion assays, fluorescence spectroscopy and initial rate kinetics and results are consistent with a binding equilibrium betweenpolyphenols, starch and PPA.
TL;DR: In this paper, a combination of branching enzymes (BE), β-amylase (BA), and transglucosidase (TG) was used to modify the branching structure of sweet potato starch.
TL;DR: In this paper, starches were isolated from six rice seeds with the same genetic background but different activities of granule-bound starch synthase I. The starch components and enzyme hydrolysis were measured and analyzed to reveal their relationships.
TL;DR: A comparison between structural, morphological, functional and digestibility studies of starches from cereals, tubers and legumes revealed that KB starch showed the highest amylose content while RS showed the lowest, and Tuber starches showed greater paste viscosities followed by legume starches.
Abstract: A comparison between structural, morphological, functional and digestibility studies of starches from cereals i.e. wheat (WS), corn (CS), low amylose corn (LACS) and rice (RS), tubers i.e. potato (PS) and sweet potato (SP), and legumes i.e. kidney bean (KB) were investigated. The shape of granules varied from oval to elliptical or spherical according to the source. Distribution of iso- amylase debranched materials revealed that long and short side chains fractions of amylopectin ranged from 12.6 to 33.1% and 40.5 to 52.5% respectively. KB starch showed the highest amylose content (49.50%) while RS showed the lowest (8.51%). Starches with greater granule size (PS, SP and KB) showed higher proportion of long side chains of amylopectin (AP) (Fr.II) than short side chains of AP (Fr.III). Peak viscosity (PV), breakdown viscosity (BV) and final viscosity (FV) showed significant positive relationship with Fr. II and negative with apparent amylose content (AAC) and Fr.III. Tuber starches showed greater paste viscosities followed by legume starches. Tuber and legume starches with higher apparent amylose content and Fr. II showed greater crystallinity. Gel hardness and gelatinization temperatures showed inverse relationship with RS starch having higher proportion of smaller granules (0–10 µm). KB with higher amylose content showed maximum rapidly digestible starch (RDS) content while SP showed the highest resistant starch. Above observations would be utilized in modifying properties of native starches and help in improving texture, moisture retention capacity and gel firmness of starch and its products.
TL;DR: These unique features of Clostridium sp.