-
Stress (Amsterdam, Netherlands) Jan 2024Compared to the in-person Trier Social Stress Test (TSST), virtual reality (VR) variants reduce resource-intensity and improve standardization but induce stress with...
Compared to the in-person Trier Social Stress Test (TSST), virtual reality (VR) variants reduce resource-intensity and improve standardization but induce stress with smaller effect sizes. However, higher cortisol reactivity is given for more immersive TSST-VRs. Immersivity depends on the VR-system, but perceived immersion may be targeted by exposure to, or interaction with the VR. We investigated whether stress reactivity towards the openly accessible OpenTSST VR can be enhanced by prior exposure to a sensorimotor game completed in VR as mediated by increased immersion. Therefore, = 58 healthy participants underwent the OpenTSST VR or its inbuilt control condition (placebo TSST-VR, pTSST-VR). Beforehand, participants completed a sensorimotor game either in VR or in real life. Stress was measured by means of self-reports, salivary cortisol concentrations, and salivary alpha-amylase (sAA) activity. Perceived immersion was assessed with the Igroup Presence Questionnaire (IPQ). The TSST-VR-group showed higher subjective stress than the pTSST-VR-group. Even though area under the curve measures indicated significant differences in cortisol levels between TSST-VR and pTSST-VR, this effect was not replicated in omnibus-analyses. Likewise, sAA was not responsive to stress. Our data suggests the OpenTSST VR does not reliably trigger physiological stress reactivity. Likewise, participants playing the VR-game before exposure to the TSST-VR did not show enhanced stress reactivity. Importantly, playing the VR-game did not lead to increased immersion (indicated by the IPQ), either. The key question resulting from our study is which manipulation may be fruitful to obtain a comparable stress response toward the TSST-VR compared to the in-person TSST.
Topics: Humans; Stress, Psychological; Hydrocortisone; Male; Virtual Reality; Female; Adult; Saliva; Young Adult; Video Games; Salivary alpha-Amylases
PubMed: 38946453
DOI: 10.1080/10253890.2024.2361237 -
Genes Jun 2024Starch degradation provides energy and signaling molecules for plant growth, development, defense, and stress response. α-amylase () is one of the most important...
Starch degradation provides energy and signaling molecules for plant growth, development, defense, and stress response. α-amylase () is one of the most important enzymes in this process. Potato tubers are rich in starch, and the hydrolysis of starch into sugar negatively impacts the frying quality of potato. Despite its importance, the gene family has not been fully explored in potatoes. Here, we performed a detailed analysis of the gene family to determine its role in potato. Twenty genes were identified across the potato genome and were divided into three subgroups. The promoters of genes contained an array of -acting elements involved in growth and development, phytohormone signaling, and stress and defense responses. , , , and were specifically expressed in mature tubers. Different gene family members tended to be upregulated in response to β-aminobutyric acid (BABA), (), benzothiadiazole (BTH), heat, salt, and drought stress. In addition, different gene family members tended to be responsive to abscisic acid (ABA), indole-3-acetic acid (IAA), gibberellic acid (GA3), and 6-benzylaminopurine (BAP) treatment. These results suggest that gene family members may be involved in starch and sugar metabolism, defense, stress response, and phytohormone signaling. The results of this study may be applicable to other starchy crops and lay a foundation for further research on the functions and regulatory mechanisms of genes.
Topics: Solanum tuberosum; Gene Expression Regulation, Plant; Plant Proteins; alpha-Amylases; Multigene Family; Stress, Physiological; Plant Growth Regulators; Gene Expression Profiling; Genome, Plant; Plant Tubers; Promoter Regions, Genetic
PubMed: 38927729
DOI: 10.3390/genes15060793 -
World Journal of Microbiology &... Jun 2024Thermophilic actinomycetes are commonly found in extreme environments and can thrive and adapt to extreme conditions. These organisms exhibit substantial variation and...
Thermophilic actinomycetes are commonly found in extreme environments and can thrive and adapt to extreme conditions. These organisms exhibit substantial variation and garnered significant interest due to their remarkable enzymatic activities. This study evaluated the potential of Streptomyces griseorubens NBR14 and Nocardiopsis synnemataformans NBRM9 strains to produce thermo-stable amylase via submerged fermentation using wheat and bean straw. The Box-Behnken design was utilized to determine the optimum parameters for amylase biosynthesis. Subsequently, amylase underwent partial purification and characterization. Furthermore, the obtained hydrolysate was applied for ethanol fermentation using Saccharomyces cerevisiae. The optimal parameters for obtaining the highest amylase activity by NBR14 (7.72 U/mL) and NBRM9 (26.54 U/mL) strains were found to be 40 and 30 °C, pH values of 7, incubation time of 7 days, and substrate concentration (3 and 2 g/100 mL), respectively. The NBR14 and NBRM9 amylase were partially purified, resulting in specific activities of 251.15 and 144.84 U/mg, as well as purification factors of 3.91 and 2.69-fold, respectively. After partial purification, the amylase extracted from NBR14 and NBRM9 showed the highest activity level at pH values of 9 and 7 and temperatures of 50 and 60 °C, respectively. The findings also indicated that the maximum velocity (V) for NBR14 and NBRM9 amylase were 57.80 and 59.88 U/mL, respectively, with K constants of 1.39 and 1.479 mM. After 48 h, bioethanol was produced at concentrations of 5.95 mg/mL and 9.29 mg/mL from hydrolyzed wheat and bean straw, respectively, through fermentation with S. cerevisiae. Thermophilic actinomycetes and their α-amylase yield demonstrated promising potential for sustainable bio-ethanol production from agro-byproducts.
Topics: Ethanol; Fermentation; Amylases; Hydrogen-Ion Concentration; Kinetics; Actinobacteria; Temperature; Triticum; Saccharomyces cerevisiae; Hydrolysis; Streptomyces; Enzyme Stability
PubMed: 38926189
DOI: 10.1007/s11274-024-04009-8 -
Marine Drugs May 2024In this research, the chemical compositions of various extracts obtained from , a type of green seaweed collected from the Nador lagoon in the northern region of...
In this research, the chemical compositions of various extracts obtained from , a type of green seaweed collected from the Nador lagoon in the northern region of Morocco, were compared. Their antioxidant and anti-diabetic properties were also studied. Using GC-MS technology, the fatty acid content of the samples was analyzed, revealing that palmitic acid, eicosenoic acid, and linoleic acid were the most abundant unsaturated fatty acids present in all samples. The HPLC analysis indicated that sinapic acid, naringin, rutin, quercetin, cinnamic acid, salicylic acid, apigenin, flavone, and flavanone were the most prevalent phenolic compounds. The aqueous extract obtained by maceration showed high levels of polyphenols and flavonoids, with values of 379.67 ± 0.09 mg GAE/g and 212.11 ± 0.11 mg QE/g, respectively. This extract also exhibited an impressive ability to scavenge DPPH radicals, as indicated by its IC value of 0.095 ± 0.12 mg/mL. Additionally, the methanolic extract obtained using the Soxhlet method demonstrated antioxidant properties by preventing β-carotene discoloration, with an IC of 0.087 ± 0.14 mg/mL. Results from in-vitro studies showed that extracts from were able to significantly inhibit the enzymatic activity of α-amylase and α-glucosidase. Among the various extracts, methanolic extract (S) has been identified as the most potent inhibitor, exhibiting a statistically similar effect to that of acarbose. Furthermore, molecular docking models were used to evaluate the interaction between the primary phytochemicals found in these extracts and the human pancreatic α-amylase and α-glucosidase enzymes. These findings suggest that extracts contain bioactive substances that are capable of reducing enzyme activity more effectively than the commercially available drug, acarbose.
Topics: Hypoglycemic Agents; Antioxidants; Ulva; Phytochemicals; Plant Extracts; Glycoside Hydrolase Inhibitors; alpha-Amylases; alpha-Glucosidases; Molecular Docking Simulation; Morocco; Humans; Chromatography, High Pressure Liquid; Polyphenols; Flavonoids; Edible Seaweeds
PubMed: 38921551
DOI: 10.3390/md22060240 -
Journal of Enzyme Inhibition and... Dec 2024Inhibition of α-glucosidase and -amylase are key tactics for managing blood glucose levels. Currently, stronger, and more accessible inhibitors are needed to treat...
Inhibition of α-glucosidase and -amylase are key tactics for managing blood glucose levels. Currently, stronger, and more accessible inhibitors are needed to treat diabetes. Indeno[1,2-] quinoxalines-carrying thiazole hybrids were created and described using NMR. All analogues were tested for hypoglycaemic effect against STZ-induced diabetes in mice. Compounds , , , and were the most potent among the synthesised analogues. These hybrids were examined for their effects on plasma insulin, urea, creatinine, GSH, MDA, ALT, AST, and total cholesterol. Moreover, these compounds were tested against -glucosidase and -amylase enzymes . The four hybrids , , , and represented moderate to potent activity with IC values 0.982 ± 0.04, to 10.19 ± 0.21 for -glucosidase inhibition and 17.58 ± 0.74 to 121.6 ± 5.14 μM for -amylase inhibition when compared to the standard medication acarbose with IC=0.316 ± 0.02 μM for -glucosidase inhibition and 31.56 ± 1.33 μM for -amylase inhibition. Docking studies as well as ADMT were done.
Topics: Quinoxalines; alpha-Amylases; alpha-Glucosidases; Molecular Docking Simulation; Hypoglycemic Agents; Animals; Mice; Structure-Activity Relationship; Glycoside Hydrolase Inhibitors; Molecular Structure; Thiazoles; Dose-Response Relationship, Drug; Diabetes Mellitus, Experimental; Streptozocin; Halogenation; Male; Enzyme Inhibitors
PubMed: 38913598
DOI: 10.1080/14756366.2024.2367128 -
Future Medicinal Chemistry 2024The objective of the present investigation was to design and synthesize new heterocyclic hybrids comprising benzothiazole and indenopyrazolone pharmacophoric units in a...
The objective of the present investigation was to design and synthesize new heterocyclic hybrids comprising benzothiazole and indenopyrazolone pharmacophoric units in a single molecular framework targeting α-amylase and α-glucosidase enzymatic inhibition. 20 new benzothiazole-appended indenopyrazoles, , were synthesized in good yields under environment-friendly conditions via cycloaddition reaction, and assessed for antidiabetic activity against α-amylase and α-glucosidase, using acarbose as the standard reference. Among all the hydroxypyrazolones, and showed the best inhibition against α-amylase and α-glucosidase, which finds support from molecular docking and dynamic studies. Compounds and have been identified as promising antidiabetic agents against α-amylase and α-glucosidase and could be considered valuable leads for further optimization of antidiabetic agents.
Topics: alpha-Glucosidases; Benzothiazoles; alpha-Amylases; Molecular Docking Simulation; Glycoside Hydrolase Inhibitors; Hypoglycemic Agents; Humans; Pyrazoles; Structure-Activity Relationship; Molecular Structure; Enzyme Inhibitors
PubMed: 38910576
DOI: 10.4155/fmc-2023-0384 -
Anais Da Academia Brasileira de Ciencias 2024In this study, the Box-Behnken experimental planning was used to optimize the extraction of polysaccharides from the cell wall of Rhizopus microspore var. oligosporus,...
In this study, the Box-Behnken experimental planning was used to optimize the extraction of polysaccharides from the cell wall of Rhizopus microspore var. oligosporus, with analysis of the quantitative effects of parameters pH, temperature and extraction time for polysaccharide yield. The optimal conditions for extraction were determined by the regression equation and evaluation of the response surface graphs, which indicated: pH 13, temperature of 120ºC and time of 60 min, with maximum yield around 18.5%. Fourier transform infrared spectroscopy analysis indicated typical polysaccharide signals. Nuclear magnetic resonance spectroscopy and monosaccharide analysis indicated a β(1,3) β(1,6) glucogalactan. The polysaccharide exhibited an average molecular weight of 120 kDa and a polymerization degree of 741. Antioxidant assays in vitro revealed the potential of polysaccharide in elimination of ABTS+ radical and hydroxyl radicals. EC50 values for free radical elimination were 7.69 and 17.8 mg/mL, for ABTS+ and hydroxyls, respectively. The polysaccharides showed potential for α-amylase inhibition with an EC50 of 1.66 mg/mL. The results suggest that β(1,3) β(1,6) glucogalactan from Rhizopus microsporus var. oligosporus can be used in biotechnological applications.
Topics: Antioxidants; Rhizopus; alpha-Amylases; Spectroscopy, Fourier Transform Infrared; Galactans; Magnetic Resonance Spectroscopy; Enzyme Inhibitors; Hydrogen-Ion Concentration
PubMed: 38896737
DOI: 10.1590/0001-3765202420230073 -
Molecules (Basel, Switzerland) May 2024Alzheimer's disease (AD) and diabetes are non-communicable diseases with global impacts. Inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are...
Alzheimer's disease (AD) and diabetes are non-communicable diseases with global impacts. Inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are suitable therapies for AD, while α-amylase and α-glucosidase inhibitors are employed as antidiabetic agents. Compounds were isolated from the medicinal plant and evaluated for their AChE, BChE, α-amylase, and α-glucosidase inhibitions. From H and C NMR data, the compounds were identified as 3,3'-di-O-methyl ellagic acid (), 3,3',4'-tri-O-methyl ellagic acid-4-O-β-D-xylopyranoside (), 3,3',4'-tri-O-methyl ellagic acid-4-O-β-D-glucopyranoside (), 3,3'-di-O-methyl ellagic acid-4-O-β-D-glucopyranoside (), myricetin-3-O-rhamnoside (), shikimic acid (), arjungenin (), terminolic acid (), 24-deoxysericoside (), arjunglucoside I (), and chebuloside II (). The derivatives of ellagic acid (-) showed moderate to good inhibition of cholinesterases, with the most potent being 3,3'-di-O-methyl ellagic acid, with IC values of 46.77 ± 0.90 µg/mL and 50.48 ± 1.10 µg/mL against AChE and BChE, respectively. The compounds exhibited potential inhibition of α-amylase and α-glucosidase, especially the phenolic compounds (-). Myricetin-3-O-rhamnoside had the highest α-amylase inhibition with an IC value of 65.17 ± 0.43 µg/mL compared to acarbose with an IC value of 32.25 ± 0.36 µg/mL. Two compounds, 3,3'-di-O-methyl ellagic acid (IC = 74.18 ± 0.29 µg/mL) and myricetin-3-O-rhamnoside (IC = 69.02 ± 0.65 µg/mL), were more active than the standard acarbose (IC = 87.70 ± 0.68 µg/mL) in the α-glucosidase assay. For α-glucosidase and α-amylase, the molecular docking results for reveal that these compounds may fit well into the binding sites of the target enzymes, establishing stable complexes with negative binding energies in the range of -4.03 to -10.20 kcalmol. Though not all the compounds showed binding affinities with cholinesterases, some had negative binding energies, indicating that the inhibition was thermodynamically favorable.
Topics: Molecular Docking Simulation; Cholinesterase Inhibitors; Hypoglycemic Agents; Plant Extracts; alpha-Amylases; Acetylcholinesterase; Terminalia; Humans; Butyrylcholinesterase; alpha-Glucosidases; Glycoside Hydrolase Inhibitors; Molecular Structure
PubMed: 38893333
DOI: 10.3390/molecules29112456 -
Plants (Basel, Switzerland) Jun 2024Alpha-amylases are crucial hydrolase enzymes which have been widely used in food, feed, fermentation, and pharmaceutical industries. Methods for low-cost production of...
Alpha-amylases are crucial hydrolase enzymes which have been widely used in food, feed, fermentation, and pharmaceutical industries. Methods for low-cost production of α-amylases are highly desirable. Soybean seed, functioning as a bioreactor, offers an excellent platform for the mass production of recombinant proteins for its ability to synthesize substantial quantities of proteins. In this study, we generated and characterized transgenic soybeans expressing the α-amylase AmyS from . The α-amylase expression cassettes were constructed for seed specific expression by utilizing the promoters of three different soybean storage peptides and transformed into soybean via -mediated transformation. The event with the highest amylase activity reached 601 U/mg of seed flour (one unit is defined as the amount of enzyme that generates 1 micromole reducing ends per min from starch at 65 °C in pH 5.5 sodium acetate buffer). The optimum pH, optimum temperature, and the enzymatic kinetics of the soybean expressed enzyme are similar to that of the expressed enzyme. However, the soybean expressed α-amylase is glycosylated, exhibiting enhanced thermostability and storage stability. Soybean AmyS retains over 80% activity after 100 min at 75 °C, and the transgenic seeds exhibit no significant activity loss after one year of storage at room temperature. The accumulated AmyS in the transgenic seeds represents approximately 15% of the total seed protein, or about 4% of the dry seed weight. The specific activity of the transgenic soybean seed flour is comparable to many commercial α-amylase enzyme products in current markets, suggesting that the soybean flour may be directly used for various applications without the need for extraction and purification.
PubMed: 38891347
DOI: 10.3390/plants13111539 -
Inhibition of human starch digesting enzymes and intestinal glucose transport by walnut polyphenols.Food Research International (Ottawa,... Aug 2024One approach to controlling type 2 diabetes (T2D) is to lower postprandialglucose spikesby slowing down the digestion of carbohydrates and the absorption of glucose in...
One approach to controlling type 2 diabetes (T2D) is to lower postprandialglucose spikesby slowing down the digestion of carbohydrates and the absorption of glucose in the small intestine. The consumption of walnuts is associated with a reduced risk of chronic diseases such as T2D, suggested to be partly due to the high content of (poly)phenols. This study evaluated, for the first time, the inhibitory effect of a (poly)phenol-rich walnut extract on human carbohydrate digesting enzymes (salivary and pancreatic α-amylases, brush border sucrase-isomaltase) and on glucose transport across fully differentiated human intestinal Caco-2/TC7 monolayers. The walnut extract was rich in multiple (poly)phenols (70 % w/w) as analysed by Folin-Ciocalteau and by LCMS. It exhibited potent inhibition of both human salivary (IC: 32.2 ± 2.5 µg walnut (poly)phenols (WP)/mL) and pancreatic (IC: 56.7 ± 1.7 µg WP/mL) α-amylases, with weaker effects on human sucrase (IC: 990 ± 20 µg WP/mL), maltase (IC: 1300 ± 80 µg WP/mL), and isomaltase (IC: 830 ± 60 µg WP/mL) activities. Selected individual walnut (poly)phenols inhibited human salivary α-amylase in the order: 1,3,4,6-tetragalloylglucose > ellagic acid pentoside > 1,2,6-tri-O-galloyl-β-D-glucopyranose, with no inhibition by ellagic acid, gallic acid and 4-O-methylgallic acid. The (poly)phenol-rich walnut extract also attenuated (up to 59 %) the transfer of 2-deoxy-D-glucose across differentiated Caco-2/TC7 cell monolayers. This is the first report on the effect of (poly)phenol-rich extracts from any commonly-consumed nut kernel on any human starch-digesting enzyme, and suggests a mechanism through which walnut consumption may lower postprandial glucose spikes and contribute to their proposed health benefits.
Topics: Humans; Polyphenols; Juglans; Caco-2 Cells; Glucose; Plant Extracts; Digestion; Nuts; Starch; alpha-Amylases; Biological Transport; Sucrase-Isomaltase Complex
PubMed: 38876610
DOI: 10.1016/j.foodres.2024.114572