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Phytochemistry Dec 2023Eleven previously undescribed lignan constituents, including five 8-O-4' type neolignans, viburnurcosides A-E (1-5), three benzofuran type neolignans, viburnurcosides...
Eleven previously undescribed lignan constituents, including five 8-O-4' type neolignans, viburnurcosides A-E (1-5), three benzofuran type neolignans, viburnurcosides F-H (6-8), and three tetrahydrofuran type lignans, viburnurcosides I-K (9-11), were isolated from the fruits of Viburnum urceolatum. The structures of all isolates were elucidated by an extensive analysis of the NMR and HRESIMS data. The absolute configurations of these compounds were determined by quantum-chemical electronic circular dichroism calculation and comparison. The sugar units of viburnurcosides A-K were identified by acid hydrolysis and HPLC analysis of the chiral derivatives of monosaccharides. The in vitro enzyme inhibition assay exhibited that viburnurcoside J (10) had the most potent inhibitory activity against α-amylase and α-glucosidase with the IC values of 19.75 and 9.14 μM, respectively, which were stronger than those of the positive control acarbose (37.31 and 26.75 μM, respectively). The potential binding modes of viburnurcoside J (10) with α-amylase and α-glucosidase were also analyzed by molecular modeling.
Topics: alpha-Glucosidases; alpha-Amylases; Viburnum; Fruit; Molecular Structure; Glycoside Hydrolase Inhibitors; Lignans
PubMed: 37827226
DOI: 10.1016/j.phytochem.2023.113895 -
World Journal of Microbiology &... Sep 2023Glucoamylases (GAs) are one of the principal groups of enzymes involved in starch hydrolysis and belong to the glycosylhydrolase family. They are classified as... (Review)
Review
Glucoamylases (GAs) are one of the principal groups of enzymes involved in starch hydrolysis and belong to the glycosylhydrolase family. They are classified as exo-amylases due to their ability to hydrolyze α-1,4 glycosidic bonds from the non-reducing end of starch, maltooligosaccharides, and related substrates, releasing β-D-glucose. Structurally, GAs possess a characteristic catalytic domain (CD) with an (α/α) fold and exhibit five conserved regions within this domain. The CD may or may not be linked to a non-catalytic domain with variable functions depending on its origin. GAs are versatile enzymes with diverse applications in food, biofuel, bioplastic and other chemical industries. Although fungal GAs are commonly employed for these purposes, they have limitations such as their low thermostability and an acidic pH requirement. Alternatively, GAs derived from prokaryotic organisms are a good option to save costs as they exhibit greater thermostability compared to fungal GAs. Moreover, a group of cold-adapted GAs from psychrophilic organisms demonstrates intriguing properties that make them suitable for application in various industries. This review provides a comprehensive overview of the structural and sequential properties as well as biotechnological applications of GAs in different industrial processes.
Topics: Glucan 1,4-alpha-Glucosidase; Amylases; Biofuels; Biotechnology; Starch
PubMed: 37653355
DOI: 10.1007/s11274-023-03731-z -
Journal of Applied Glycoscience 2023In this study, we investigated the changes in composition, microstructure, and starch molecular structure of shochu koji during preparation. We observed that the...
In this study, we investigated the changes in composition, microstructure, and starch molecular structure of shochu koji during preparation. We observed that the gelatinized and outer part of starch was decomposed in priority during the early and middle preparation stages. The gap between the starch granules increased with the delayed time. Finally, the koji microstructure became spongy. Shochu koji mold produced two α-amylases in different expression manners. Acid-labile α-amylase was produced in the early and middle preparation stages. Acid-stable α-amylase and saccharification power were produced in the middle and late stages. Throughout the koji preparation, reducing sugars content reached approximately 13-20 % of the total sugar content, with glucose representing over 70 % of the reducing sugars. α-Glucan fragments with C chains of degree of polymerization (DP) 4-73 were observed in the early and middle stages (<23 h), indicating the degradation of amylopectin at long B chains. In the latter stage, the amount of C chains of DP 6-30 decreased, while the longer C chains (DP 30<) did not change. These results showed that acid-labile α-amylase, acid-stable α-amylase, and saccharification enzymes including glucoamylase and α-glucosidase work preferentially on the amorphous regions of starch granules, and cooperative action of these enzymes during koji preparation contributes to the formation of the observed microstructure. Our study is the first report on the decomposition schemes of starch and the microstructure forming process in shochu koji.
PubMed: 38239766
DOI: 10.5458/jag.jag.JAG-2023_0006 -
Food Microbiology Sep 2023Hop creep continues to present an unresolved issue for the brewing industry, specifically stemming from those hops added to beer during fermentation. Hops have been... (Review)
Review
BACKGROUND
Hop creep continues to present an unresolved issue for the brewing industry, specifically stemming from those hops added to beer during fermentation. Hops have been found to contain four dextrin-degrading enzymes: alpha amylase, beta amylase, limit dextrinase, and an amyloglucosidase. One recent hypothesis predicts that these dextrin-degrading enzymes could originate from microbes rather than the hop plant itself.
SCOPE AND APPROACH
This review begins by describing how hops are processed and used in the brewing industry. It will then discuss hop creep's origins with a new beer style, antimicrobial factors from hops and resistance mechanisms that bacteria use to counter them, and finally microbial communities that inhabit hops, focusing on whether they can produce the starch degrading enzymes which drive hop creep. After initial identification, microbes with possible links to hop creep were then run through several databases to search the genomes (if available) and for those specific enzymes.
KEY FINDINGS AND CONCLUSIONS
Several bacteria and fungi contain alpha amylase as well as unspecified glycosyl hydrolases, but only one contains beta amylase. Finally, this paper closes with a short summary of how abundant these organisms typically are in other flowers.
Topics: Humulus; beta-Amylase; Dextrins; alpha-Amylases; Beer
PubMed: 37290874
DOI: 10.1016/j.fm.2023.104298 -
Bioorganic Chemistry Jun 2024Diabetes mellitus is a metabolic disease characterized by hyperglycemia, which can be counteracted by the inhibition of α-glucosidase (α-Glu) and α-amylase (α-Amy),...
Diabetes mellitus is a metabolic disease characterized by hyperglycemia, which can be counteracted by the inhibition of α-glucosidase (α-Glu) and α-amylase (α-Amy), enzymes responsible for the hydrolysis of carbohydrates. In recent decades, many natural compounds and their bioinspired analogues have been studied as α-Glu and α-Amy inhibitors. However, no studies have been devoted to the evaluation of α-Glu and α-Amy inhibition by the neolignan obovatol (1). In this work, we report the synthesis of 1 and a library of new analogues. The synthesis of these compounds was achieved by implementing methodologies based on: phenol allylation, Claisen/Cope rearrangements, methylation, Ullmann coupling, demethylation, phenol oxidation and Michael-type addition. Obovatol (1) and ten analogues were evaluated for their in vitro inhibitory activity towards α-Glu and α-Amy. Our investigation highlighted that the naturally occurring 1 and four neolignan analogues (11, 22, 26 and 27) were more effective inhibitors than the hypoglycemic drug acarbose (α-Amy: 34.6 µM; α-Glu: 248.3 µM) with IC value of 6.2-23.6 µM toward α-Amy and 39.8-124.6 µM toward α-Glu. Docking investigations validated the inhibition outcomes, highlighting optimal compatibility between synthesized neolignans and both the enzymes. Concurrently circular dichroism spectroscopy detected the conformational changes in α-Glu induced by its interaction with the studied neolignans. Detailed studies through fluorescence measurements and kinetics of α-Glu and α-Amy inhibition also indicated that 1, 11, 22, 26 and 27 have the greatest affinity for α-Glu and 1, 11 and 27 for α-Amy. Surface plasmon resonance imaging (SPRI) measurements confirmed that among the compounds studied, the neolignan 27 has the greater affinity for both enzymes, thus corroborating the results obtained by kinetics and fluorescence quenching. Finally, in vitro cytotoxicity of the investigated compounds was tested on human colon cancer cell line (HCT-116). All these results demonstrate that these obovatol-based neolignan analogues constitute promising candidates in the pursuit of developing novel hypoglycemic drugs.
Topics: alpha-Amylases; alpha-Glucosidases; Glycoside Hydrolase Inhibitors; Lignans; Structure-Activity Relationship; Humans; Molecular Structure; Dose-Response Relationship, Drug; Molecular Docking Simulation; Hypoglycemic Agents; Enzyme Inhibitors
PubMed: 38723423
DOI: 10.1016/j.bioorg.2024.107392 -
International Journal of Biological... Sep 2023The best amylolytic activity production by Aspergillus clavatus UEM 04 occurred in submersed culture, with starch, for 72 h, at 25 °C, and 100 rpm. Exclusion...
The best amylolytic activity production by Aspergillus clavatus UEM 04 occurred in submersed culture, with starch, for 72 h, at 25 °C, and 100 rpm. Exclusion chromatography partially purified two enzymes, which ran as unique bands in SDS-PAGE with approximately 84 kDa. LC-MS/MS identified a glucoamylase (GH15) and an α-amylase (GH13_1) as the predominant proteins and other co-purified proteins. Zn, Cu, and Mn activated the glucoamylase, and SDS, Zn, Fe, and Cu inhibited the α-amylase. The α-amylase optimum pH was 6.5. The optimal temperatures for the glucoamylase and α-amylase were 50 °C and 40 °C, and the T was 53.1 °C and 56.3 °C, respectively. Both enzymes remained almost fully active for 28-32 h at 40 °C, but the α-amylase thermal stability was calcium-dependent. Furthermore, the glucoamylase and α-amylase K for starch were 2.95 and 1.0 mg/mL, respectively. Still, the V was 0.28 μmol/min of released glucose for glucoamylase and 0.1 mg/min of consumed starch for α-amylase. Moreover, the glucoamylase showed greater affinity for amylopectin and α-amylase for maltodextrin. Additionally, both enzymes efficiently degraded raw starch. At last, glucose was the main product of glucoamylase, and α-amylase produced mainly maltose from gelatinized soluble starch hydrolysis.
Topics: alpha-Amylases; Glucan 1,4-alpha-Glucosidase; Starch; Chromatography, Liquid; Tandem Mass Spectrometry; Glucose; Hydrogen-Ion Concentration
PubMed: 37479205
DOI: 10.1016/j.ijbiomac.2023.125890 -
Journal of the Science of Food and... Aug 2023Dipeptidyl peptidase-IV (DPP-IV), α-glucosidase, and α-amylase play a prominent role in regulating postprandial blood sugar levels, which are regarded as key targets... (Review)
Review
BACKGROUND
Dipeptidyl peptidase-IV (DPP-IV), α-glucosidase, and α-amylase play a prominent role in regulating postprandial blood sugar levels, which are regarded as key targets for the treatment of type 2 diabetes mellitus (T2DM). The present study aimed to characterize bioactive compounds as potent crucial sugar metabolism enzyme inhibitors from sugarcane leaves by virtual screening. In total, 41 sugarcane leaf-derived compounds were used for the screening of multiple targets. Subsequently, the molecular mechanism and activity validation in vitro of the interaction between enzymes and compound were carried out.
RESULTS
Flavonoid compound schaftoside was identified by molecular simulation and showed significant DPP-IV (0.1050 ± 1.22 mmol L ), α-glucosidase (0.078 ± 0.06 mmol L ), and α-amylase (0.3067 ± 0.35 mmol L ) inhibitory effects. The residues ARG125 and TYR662 of DPP-IV may play crucial roles in inhibiting the activity of DPP-IV. Multiple hydrogen bonds and electrostatic interactions were exhibited between schaftoside and α-glucosidase. Molecular modeling revealed that schaftoside displays strong binding with the catalytic triad (ASP197, ASP300, and GLU233) of α-amylase.
CONCLUSION
Our findings demonstrate that schaftoside from sugarcane leaves might be an edible for T2DM treatment." © 2023 Society of Chemical Industry.
Topics: Humans; Hypoglycemic Agents; alpha-Glucosidases; Dipeptidyl-Peptidase IV Inhibitors; Molecular Docking Simulation; Diabetes Mellitus, Type 2; Saccharum; Dipeptidyl Peptidase 4; alpha-Amylases; Plant Leaves; Glycoside Hydrolase Inhibitors
PubMed: 37038045
DOI: 10.1002/jsfa.12613 -
Essays in Biochemistry Aug 2023(Hyper)thermophilic archaeal glycosidases are enzymes that catalyze the hydrolysis of glycosidic bonds to break down complex sugars and polysaccharides at high... (Review)
Review
(Hyper)thermophilic archaeal glycosidases are enzymes that catalyze the hydrolysis of glycosidic bonds to break down complex sugars and polysaccharides at high temperatures. These enzymes have an unique structure that allows them to remain stable and functional in extreme environments such as hot springs and hydrothermal vents. This review provides an overview of the current knowledge and milestones on the structures and functions of (hyper)thermophilic archaeal glycosidases and their potential applications in various fields. In particular, this review focuses on the structural characteristics of these enzymes and how these features relate to their catalytic activity by discussing different types of (hyper)thermophilic archaeal glycosidases, including β-glucosidases, chitinase, cellulases and α-amylases, describing their molecular structures, active sites, and mechanisms of action, including their role in the hydrolysis of carbohydrates. By providing a comprehensive overview of (hyper)thermophilic archaeal glycosidases, this review aims to stimulate further research into these fascinating enzymes.
Topics: Glycoside Hydrolases; Archaea; Hot Temperature; Hydrolysis
PubMed: 37341134
DOI: 10.1042/EBC20220196 -
International Journal of... Dec 2023Psychologically aggressive parenting (PAP) exposure negatively affects children's development of aggression. Nevertheless, not all children exposed to PAP display...
Psychologically aggressive parenting (PAP) exposure negatively affects children's development of aggression. Nevertheless, not all children exposed to PAP display aggressive behaviors. Sympathetic nervous system (SNS) activity may influence the impact of early adversity on aggression. This study examines whether SNS reactivity and sex moderate the link between psychologically aggressive parenting (PAP) during childhood and later aggression. Emerging adults (N = 182, mean age = 19.03 years, 53 % female) retrospectively reported on their childhood PAP and current aggression. Salivary alpha-amylase (sAA) collected from a social stress task indexed SNS reactivity to stress. Childhood PAP was associated with emerging adulthood anger, hostility, physical, and verbal aggression. Moreover, males were more likely to exhibit anger, verbal, and physical aggression and had higher levels of sAA reactivity than females. A significant three-way interaction between childhood PAP, sAA reactivity, and sex accounted for participants' current verbal aggression. The link between childhood PAP and later verbal aggression was stronger for males at higher levels of sAA reactivity. Females with higher levels of sAA reactivity displayed lower levels of verbal aggression regardless of PAP exposure. Males and females with lower levels of sAA reactivity were at elevated risk for verbal aggression regardless of PAP exposure. Moreover, we found a significant two-way interaction between PAP and sex on anger, such that higher levels of PAP exposure were associated with more anger among males, but not females. These findings highlight the importance of examining interactions between biological and environmental factors and sex in accounting for later aggression.
Topics: Male; Child; Adult; Humans; Female; Young Adult; Salivary alpha-Amylases; Parenting; Retrospective Studies; Aggression; Anger
PubMed: 37939902
DOI: 10.1016/j.ijpsycho.2023.112260 -
Computational Biology and Chemistry Oct 2023In our effort to develop potent anti-hyperglycemic compounds with inhibitory activity against α-amylase and α-glucosidase, a series of novel quinoxaline-isoxazole...
In our effort to develop potent anti-hyperglycemic compounds with inhibitory activity against α-amylase and α-glucosidase, a series of novel quinoxaline-isoxazole moieties were synthesized. The novel quinoxaline-isoxazole derivatives were assessed in vitro for their anti-hyperglycemic activities on α-amylase and α-glucosidase inhibitions. The results revealed promising IC values compared to acarbose as a positive control for α-amylase and α-glucosidase. Among them, N-Ethyl-7-chloro-3-((3-phenylisoxazol-5-yl)methoxy)quinoxalin-2-amine 5b showed dual inhibitory with IC of 24.0 µM for α-amylase and 41.7 µM for α-glucosidase. In addition, N-Ethyl-7-methoxy-3-((3-(2-chlorophenyl)isoxazol-5-yl)methoxy)quinoxalin-2-amine 5j also had dual bioactivities against α-amylase and α-glucosidase with IC of 17.0 and 40.1 µM, respectively. Nevertheless, two more compounds N-Ethyl-7-cyano-3-((3-phenylisoxazol-5-yl)methoxy)quinoxaline-2-amine 5e showed strong mono-inhibition for α-glucosidase with IC of 16.6 µM followed by N-Ethyl-7-methoxy-3-((3-phenylisoxazol-5-yl)methoxy)quinoxalin-2-amine 5 f with IC of 18.6 µM. The molecular docking study for α-glucosidase inhibitor provided the binding energy ranging from 8.3 to 9.1 kcal/mol and α-amylase inhibitor showed the binding energy score at 8.4 and 8.5 kcal/mol. The dual inhibitions nature of 5b and 5j were further analyzed and confirmed via molecular dynamics including the stability of the compound, interaction energy, binding free energy, and the interaction residue analysis using the MM-GBSA approach. The results showed that compound 5j was the most potent compound. Lastly, the drug-likeness properties were also evaluated with all synthesized compounds 5a-5j and the results reveal that all potent compounds meet Lipinski's rules of five.
Topics: Molecular Docking Simulation; alpha-Glucosidases; Quinoxalines; Glycoside Hydrolase Inhibitors; alpha-Amylases; Molecular Structure; Structure-Activity Relationship
PubMed: 37542847
DOI: 10.1016/j.compbiolchem.2023.107938