Impact of L-theanine and L-tyrosine on markers of stress and cognitive performance in response to a virtual reality based active shooter training drill.

Ingestion of L-theanine and L-tyrosine has been shown to reduce salivary stress biomarkers and improve aspects of cognitive performance in response to stress. However, there have been no studies to concurrently examine the impact of both L-theanine and L-tyrosine ingestion during a mental stress challenge (MSC) involving a brief cognitive challenge and a virtual reality based active shooter training drill. Thus, the purpose of this study was to determine the impact of ingestion of L-theanine and L-tyrosine on markers of stress and cognitive performance in response to a virtual reality active shooter drill and cognitive challenge. The cognitive challenge involved a Stroop challenge and mental arithmetic. Eighty subjects (age = 21 ± 2.6 yrs; male = 46; female = 34) were randomly assigned L-tyrosine (n = 28; 2000 mg), L-theanine (n = 25; 200 mg), or placebo (n = 27) prior to MSC exposure. Saliva samples, state-anxiety inventory (SAI) scales, and heart rate (HR) were collected before and after exposure to the MSC. Saliva was analyzed for stress markers α-amylase (sAA) and secretory immunoglobulin A (SIgA). The MSC resulted in significant increases in sAA, SIgA, HR, and SAI. Ingestion of L-theanine and L-tyrosine did not impact markers of stress. However, the L-tyrosine treatment demonstrated significantly lower missed responses compared to the placebo treatment group during the Stroop challenge. These data demonstrate that ingestion of L-theanine or L-tyrosine does not impact markers of stress in response to a MSC but may impact cognitive performance. This study was pre-registered as a clinical trial ("Impact of supplements on stress markers": NCT05592561).

Genome-Wide Identification and Expression Profiling of the α-Amylase (AMY) Gene Family in Potato.

Starch degradation provides energy and signaling molecules for plant growth, development, defense, and stress response. α-amylase (AMY) 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 AMY gene family has not been fully explored in potatoes. Here, we performed a detailed analysis of the StAMY gene family to determine its role in potato. Twenty StAMY genes were identified across the potato genome and were divided into three subgroups. The promoters of StAMY genes contained an array of cis-acting elements involved in growth and development, phytohormone signaling, and stress and defense responses. StAMY8, StAMY9, StAMY12, and StAMY20 were specifically expressed in mature tubers. Different StAMY gene family members tended to be upregulated in response to ß-aminobutyric acid (BABA), Phytophthora infestans (P. infestans), benzothiadiazole (BTH), heat, salt, and drought stress. In addition, different StAMY 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 StAMY 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 AMY genes.

Fluorinated indeno-quinoxaline bearing thiazole moieties as hypoglycaemic agents targeting α-amylase, and α-glucosidase: synthesis, molecular docking, and ADMET studies.

Inhibition of α-glucosidase and α-amylase are key tactics for managing blood glucose levels. Currently, stronger, and more accessible inhibitors are needed to treat diabetes. Indeno[1,2-b] quinoxalines-carrying thiazole hybrids 1-17 were created and described using NMR. All analogues were tested for hypoglycaemic effect against STZ-induced diabetes in mice. Compounds 4, 6, 8, and 16 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 α-glucosidase and α-amylase enzymes in vitro. The four hybrids 4, 6, 8, and 16 represented moderate to potent activity with IC50 values 0.982 ± 0.04, to 10.19 ± 0.21 for α-glucosidase inhibition and 17.58 ± 0.74 to 121.6 ± 5.14 µM for α-amylase inhibition when compared to the standard medication acarbose with IC50=0.316 ± 0.02 µM for α-glucosidase inhibition and 31.56 ± 1.33 µM for α-amylase inhibition. Docking studies as well as in silico ADMT were done.

Proteomic Analysis of Differences in the Freezability of Porcine Sperm Identifies α-Amylase As a Key Protein.

To investigate the mechanisms underlying the differences in the freezability of boar semen, Yorkshire boars with freezing-tolerant semen (YT, n = 3), Yorkshire boars with freezing-sensitive semen (YS, n = 3), Landrace boars with freezing-tolerant semen (LT, n = 3), and Landrace boars with freezing-sensitive semen (LS, n = 3) were selected for this study. Their sperm was subjected to protein extraction, followed by data-independent acquisition proteomics and functional bioinformatics analysis. A total of 3042 proteins were identified, of which 2810 were quantified. Some key KEGG pathways were enriched, such as starch and sucrose metabolism, carbohydrate digestion and absorption, mineral absorption, the HIF-1 signaling pathway, and the necroptosis pathways. Through PRM verification, we found that several proteins, such as α-amylase and epididymal sperm-binding protein 1, can be used as molecular markers of the freezing resistance of boar semen. Furthermore, we found that the addition of α-amylase to cryoprotective extender could significantly improve the post-thaw motility and quality of boar semen. In summary, this study revealed some molecular markers and potential molecular pathways contributing to the high or low freezability of boar sperm, identifying α-amylase as a key protein. This study is valuable for optimizing boar semen cryopreservation technology.

Facile synthesis and in silico studies of benzothiazole-linked hydroxypyrazolones targeting α-amylase and α-glucosidase.

Aim: 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. Materials & methods: 20 new benzothiazole-appended indenopyrazoles, 3a-t, 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. Results: Among all the hydroxypyrazolones, 3p and 3r showed the best inhibition against α-amylase and α-glucosidase, which finds support from molecular docking and dynamic studies. Conclusion: Compounds 3p and 3r 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.

[Box: see text].

Effects of adding proteins from different sources during heat-moisture treatment on corn starch structure, physicochemical and in vitro digestibility.

Proteins impact starch digestion, but the specific mechanism under heat-moisture treatment remains unclear. This study examined how proteins from various sources-white kidney bean, soybean, casein, whey-altered corn starch's structure, physicochemical properties, and digestibility during heat-moisture treatment (HMT). HMT and protein addition could significantly reduce starch's digestibility. The kidney bean protein-starch complex under HMT had the highest resistant starch at 19.74 %. Most proteins effectively inhibit α-amylase, with kidney bean being the most significantly (IC50 = 1.712 ± 0.085 mg/mL). HMT makes starch obtain a more rigid structure, limits its swelling ability, and reduces paste viscosity and amylose leaching. At the same time, proteins also improve starch's short-range order, acting as a physical barrier to digestion. Rheological and low-field NMR analyses revealed that protein enhanced the complexes' shear stability and water-binding capacity. These findings enrich the understanding of how proteins from different sources affect starch digestion under HMT, aiding the creation of nutritious, hypoglycemic foods.

Structure-function relationships in (poly)phenol-enzyme binding: Direct inhibition of human salivary and pancreatic α-amylases.

(Poly)phenols inhibit α-amylase by directly binding to the enzyme and/or by forming starch-polyphenol complexes. Conventional methods using starch as the substrate measure inhibition from both mechanisms, whereas the use of shorter oligosaccharides as substrates exclusively measures the direct interaction of (poly)phenols with the enzyme. In this study, using a chromatography-based method and a short oligosaccharide as the substrate, we investigated the detailed structural prerequisites for the direct inhibition of human salivary and pancreatic α-amylases by over 50 (poly)phenols from the (poly)phenol groups: flavonols, flavones, flavanones, flavan-3-ols, polymethoxyflavones, isoflavones, anthocyanidins and phenolic acids. Despite being structurally very similar (97% sequence homology), human salivary and pancreatic α-amylases were inhibited to different extents by the tested (poly)phenols. The most potent human salivary α-amylase inhibitors were luteolin and pelargonidin, while the methoxylated anthocyanidins, peonidin and petunidin, significantly blocked pancreatic enzyme activity. B-ring methoxylation of anthocyanidins increased inhibition against both human α-amylases while hydroxyl groups at C3 and B3' acted antagonistically in human salivary inhibition. C4 carbonyl reduction, or the positive charge on the flavonoid structure, was the key structural feature for human pancreatic inhibition. B-ring glycosylation did not affect salivary enzyme inhibition, but increased pancreatic enzyme inhibition when compared to its corresponding aglycone. Overall, our findings indicate that the efficacy of interaction with human α-amylase is mainly influenced by the type and placement of functional groups rather than the number of hydroxyl groups and molecular weight.

Inhibition of human starch digesting enzymes and intestinal glucose transport by walnut polyphenols.

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 (IC50: 32.2 ± 2.5 µg walnut (poly)phenols (WP)/mL) and pancreatic (IC50: 56.7 ± 1.7 µg WP/mL) α-amylases, with weaker effects on human sucrase (IC50: 990 ± 20 µg WP/mL), maltase (IC50: 1300 ± 80 µg WP/mL), and isomaltase (IC25: 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-ß-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.

New natural protein tyrosine phosphatase 1B inhibitors from Gynostemma pentaphyllum.

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease mainly caused by insulin resistance, which can lead to a series of complications such as cardiovascular disease, retinopathy, and its typical clinical symptom is hyperglycaemia. Glucosidase inhibitors, including Acarbose, Miglitol, are commonly used in the clinical treatment of hypoglycaemia. In addition, Protein tyrosine phosphatase 1B (PTP1B) is also an important promising target for the treatment of T2DM. Gynostemma pentaphyllum is a well-known oriental traditional medicinal herbal plant, and has many beneficial effects on glucose and lipid metabolism. In the present study, three new and nine known dammarane triterpenoids isolated from G. pentaphyllum, and their structures were elucidated by spectroscopic methods including HR-ESI-MS,1H and 13C NMR and X-ray crystallography. All these compounds were evaluated for inhibitory activity against α-glucosidase, α-amylase and PTP1B. The results suggested that compounds 7∼10 were potential antidiabetic agents with significantly inhibition activity against PTP1B in a dose-dependent manner.

In Vitro and Molecular Docking Evaluation of the Anticholinesterase and Antidiabetic Effects of Compounds from Terminalia macroptera Guill. & Perr. (Combretaceae).

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 Terminalia macroptera and evaluated for their AChE, BChE, α-amylase, and α-glucosidase inhibitions. From 1H and 13C NMR data, the compounds were identified as 3,3'-di-O-methyl ellagic acid (1), 3,3',4'-tri-O-methyl ellagic acid-4-O-ß-D-xylopyranoside (2), 3,3',4'-tri-O-methyl ellagic acid-4-O-ß-D-glucopyranoside (3), 3,3'-di-O-methyl ellagic acid-4-O-ß-D-glucopyranoside (4), myricetin-3-O-rhamnoside (5), shikimic acid (6), arjungenin (7), terminolic acid (8), 24-deoxysericoside (9), arjunglucoside I (10), and chebuloside II (11). The derivatives of ellagic acid (1-4) showed moderate to good inhibition of cholinesterases, with the most potent being 3,3'-di-O-methyl ellagic acid, with IC50 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 (1-5). Myricetin-3-O-rhamnoside had the highest α-amylase inhibition with an IC50 value of 65.17 ± 0.43 µg/mL compared to acarbose with an IC50 value of 32.25 ± 0.36 µg/mL. Two compounds, 3,3'-di-O-methyl ellagic acid (IC50 = 74.18 ± 0.29 µg/mL) and myricetin-3-O-rhamnoside (IC50 = 69.02 ± 0.65 µg/mL), were more active than the standard acarbose (IC50 = 87.70 ± 0.68 µg/mL) in the α-glucosidase assay. For α-glucosidase and α-amylase, the molecular docking results for 1-11 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-1. Though not all the compounds showed binding affinities with cholinesterases, some had negative binding energies, indicating that the inhibition was thermodynamically favorable.

Explore new quinoxaline pharmacophore tethered sulfonamide fragments as in vitro α-glucosidase, α-amylase, and acetylcholinesterase inhibitors with ADMET and molecular modeling simulation.

A new series of quinoxaline-sulfonamide derivatives 3-12 were synthesized using fragment-based drug design by reaction of quinoxaline sulfonyl chloride (QSC) with different amines and hydrazines. The quinoxaline-sulfonamide derivatives were evaluated for antidiabetic and anti-Alzheimer's potential against α-glucosidase, α-amylase, and acetylcholinesterase enzymes. These derivatives showed good to moderate potency against α-amylase and α-glucosidase with inhibitory percentages between 24.34 ± 0.01%-63.09 ± 0.02% and 28.95 ± 0.04%-75.36 ± 0.01%, respectively. Surprisingly, bis-sulfonamide quinoxaline derivative 4 revealed the most potent activity with inhibitory percentages of 75.36 ± 0.01% and 63.09 ± 0.02% against α-glucosidase and α-amylase compared to acarbose (IP = 57.79 ± 0.01% and 67.33 ± 0.01%), respectively. Moreover, the quinoxaline derivative 3 exhibited potency as α-glucosidase and α-amylase inhibitory with a minute decline from compound 4 and acarbose with inhibitory percentages of 44.93 ± 0.01% and 38.95 ± 0.01%. Additionally, in vitro acetylcholinesterase inhibitory activity for designed derivatives exhibited weak to moderate activity. Still, sulfonamide-quinoxaline derivative 3 emerged as the most active member with inhibitory percentage of 41.92 ± 0.02% compared with donepezil (IP = 67.27 ± 0.60%). The DFT calculations, docking simulation, target prediction, and ADMET analysis were performed and discussed in detail.

Detergent-resistant α-amylase derived from Anoxybacillus karvacharensis K1 and its production based on whey.

In the field of biotechnology, the utilization of agro-industrial waste for generating high-value products, such as microbial biomass and enzymes, holds significant importance. This study aimed to produce recombinant α-amylase from Anoxybacillus karvacharensis strain K1, utilizing whey as an useful growth medium. The purified hexahistidine-tagged α-amylase exhibited remarkable homogeneity, boasting a specific activity of 1069.2 U mg-1. The enzyme displayed its peak activity at 55 °C and pH 6.5, retaining approximately 70% of its activity even after 3 h of incubation at 55 °C. Its molecular weight, as determined via SDS-PAGE, was approximately 69 kDa. The α-amylase demonstrated high activity against wheat starch (1648.8 ± 16.8 U mg-1) while exhibiting comparatively lower activity towards cyclodextrins and amylose (≤ 200.2 ± 16.2 U mg-1). It exhibited exceptional tolerance to salt, withstanding concentrations of up to 2.5 M. Interestingly, metal ions and detergents such as sodium dodecyl sulfate (SDS), Triton 100, Triton 40, and Tween 80, 5,5'-dithio-bis-[2-nitrobenzoic acid (DNTB), ß-mercaptoethanol (ME), and dithiothreitol (DTT) had no significant inhibitory effect on the enzyme's activity, and the presence of CaCl2 (2 mM) even led to a slight activation of the recombinant enzyme (1.4 times). The Michaelis constant (Km) and maximum reaction rate (Vmax), were determined using soluble starch as a substrate, yielding values of 1.2 ± 0.19 mg mL-1 and 1580.3 ± 183.7 µmol mg-1 protein min-1, respectively. Notably, the most favorable conditions for biomass and recombinant α-amylase production were achieved through the treatment of acid whey with ß-glucosidase for 24 h.

Proprietary alpha-amylase inhibitor formulation from white kidney bean (Phaseolus vulgaris L.) promotes weight and fat loss: a 12-week, double-blind, placebo-controlled, randomized trial.

White kidney bean (Phaseolus vulgaris L.) extracts can aid weight management by reducing calorie intake from complex carbohydrates through alpha-amylase inhibition. We examined the impact of a proprietary aqueous extract from whole dried white kidney beans standardized by its alpha-amylase inhibitor activity (Phase 2 white kidney bean extract (WKBE)) on weight management in subjects with overweight and moderate obesity. In a randomized, double-blind, placebo-controlled fashion, 81 participants completed the study and ingested either a high dose of Phase 2 (1000 mg, WKBE HIGH), a low dose (700 mg, WKBE LOW), or a matching placebo (microcrystalline cellulose, PLA) three times a day, 30 min before meals, for 12 weeks during a calorie restricted diet. In a dose-dependent manner, Phase 2 significantly reduced body weight, fat mass, BMI, waist, hip and in the WKBE HIGH group thigh circumference. Phase 2 is an effective and safe supplement aiding weight and fat loss. ClinicalTrials.gov identifier NCT02930668.

Discovery of novel 6-(piperidin-1-ylsulfonyl)-2H-chromenes targeting α-glucosidase, α-amylase, and PPAR-γ: Design, synthesis, virtual screening, and anti-diabetic activity for type 2 diabetes mellitus.

A new series of 2H-chromene-based sulfonamide derivatives 3-12 has been synthesized and characterized using different spectroscopic techniques. The synthesized 2H-chromenes were synthesized by reacting activated methylene with 5-(piperidin-1-ylsulfonyl)salicylaldehyde through one-step condensation followed by intramolecular cyclization. Virtual screening of the designed molecules on α-glucosidase enzymes (PDB: 3W37 and 3A4A) exhibited good binding affinity suggesting that these derivatives may be potential α-glucosidase inhibitors. In-vitro α-glucosidase activity was conducted firstly at 100 µg/mL, and the results demonstrated good inhibitory potency with values ranging from 90.6% to 96.3% compared to IP = 95.8% for Acarbose. Furthermore, the IC50 values were determined, and the designed derivatives exhibited inhibitory potency less than 11 µg/mL. Surprisingly, two chromene derivatives 6 and 10 showed the highest potency with IC50 values of 0.975 ± 0.04 and 0.584 ± 0.02 µg/mL, respectively, compared to Acarbose (IC50 = 0.805 ± 0.03 µg/mL). Moreover, our work was extended to evaluate the in-vitro α-amylase and PPAR-γ activity as additional targets for diabetic activity. The results exhibited moderate activity on α-amylase and potency as PPAR-γ agonist making it a multiplet antidiabetic target. The most active 2H-chromenes 6 and 10 exhibited significant activity to PPAR-γ with IC50 values of 3.453 ± 0.14 and 4.653 ± 0.04 µg/mL compared to Pioglitazone (IC50 = 4.884±0.29 µg/mL) indicating that these derivatives improve insulin sensitivity by stimulating the production of small insulin-sensitive adipocytes. In-silico ADME profile analysis indicated compliance with Lipinski's and Veber's rules with excellent oral bioavailability properties. Finally, the docking simulation was conducted to explain the expected binding mode and binding affinity.

Automated optimization of the solubility of a hyper-stable α-amylase.

Most successes in computational protein engineering to date have focused on enhancing one biophysical trait, while multi-trait optimization remains a challenge. Different biophysical properties are often conflicting, as mutations that improve one tend to worsen the others. In this study, we explored the potential of an automated computational design strategy, called CamSol Combination, to optimize solubility and stability of enzymes without affecting their activity. Specifically, we focus on Bacillus licheniformis α-amylase (BLA), a hyper-stable enzyme that finds diverse application in industry and biotechnology. We validate the computational predictions by producing 10 BLA variants, including the wild-type (WT) and three designed models harbouring between 6 and 8 mutations each. Our results show that all three models have substantially improved relative solubility over the WT, unaffected catalytic rate and retained hyper-stability, supporting the algorithm's capacity to optimize enzymes. High stability and solubility embody enzymes with superior resilience to chemical and physical stresses, enhance manufacturability and allow for high-concentration formulations characterized by extended shelf lives. This ability to readily optimize solubility and stability of enzymes will enable the rapid and reliable generation of highly robust and versatile reagents, poised to contribute to advancements in diverse scientific and industrial domains.

Analysis of the association between salivary proteins and oral mucositis in patients with head and neck cancer undergoing IMRT: a longitudinal study.

INTRODUCTION: This longitudinal study assessed the association between salivary protein composition and the clinical onset/severity of oral mucositis (OM) in patients with head and neck tumours treated with intensity-modulated-radiotherapy (IMRT). METHODS: Saliva samples/clinical data were obtained from 40 head and neck cancer patients treated at Guy's Hospital before -IMRT(T0) and after-IMRT (T1 = 6 m, T2 = 12 m) (ethics approval/consent). Salivary flow rate, total protein concentration, and secretion rate were determined from saliva samples and compared with pre-treatment values. OM was assessed, total/specific salivary proteins, including mucin 5B and 7, IgA, cystatin-S, albumin, and α-amylase, were quantified. RESULTS: 95% patients experienced OM during IMRT, with 33 subjects reaching grade 2&3. At T1, there was a significant reduction in salivary flow rate, total protein secretion rate, α-amylase and cystatin-S compared to baseline. Remarkably IMRT did not significantly alter mucin 5B and 7, or the IgA secretion rate at any time point. At T1, all the analyzed proteins were associated with the OM outcomes. In addition, there was a significant inverse correlation between IgA concentration at T0 and the severity of OM during IMRT. CONCLUSION: This study revealed significant associations between several salivary proteins and OM in patients with head and neck cancer undergoing IMRT. Further longitudinal studies are needed to confirm these results. CLINICAL SIGNIFICANCE: The study contributes to the understanding of certain salivary proteins association with OM. This could be the first step towards identifying potential salivary markers that could offer perspectives for personalized medicine approaches to improve their quality of life (QoL). RESEARCH QUESTION: What is the association between salivary proteins and the occurrence and severity of OM in head and neck cancer patients? AIM: To assess the association between salivary protein composition with the clinical onset/severity of oral mucositis (OM) in head and neck cancer patients treated with intensity modulated radiotherapy. NULL HYPOTHESIS: There is no association between salivary proteins and onset/severity of OM in HNC patients.

Effect of freezing rates on α-amylase enzymatic susceptibility, in vitro digestibility, and technological properties of starch microparticles.

The aim of this study was to evaluate the effect of freezing rates using direct (LF: Liquid nitrogen) and indirect (RF: Cryogenic refrigerator and UF: ultra-freezer) methods at temperatures of (-20, -80, and - 196 °C) on the enzymatic susceptibility with α-amylase for microparticles. In vitro digestibility parameters and technological properties were also analyzed. Lower rates resulted in larger ice crystals, damaging the starch structure. Hydrolysis was more pronounced at slower rates RF: 0.07 °C/min and UF: 0.14 °C/min, yielding maximum values of RDS: 37.63% and SDS: 59.32% for RF. Type A crystallinity remained unchanged, with only a noted increase in crystallinity of up to 6.50% for FR. Starch pastes were classified as pseudoplastic, with RF exhibiting superior textural parameters and apparent viscosity. (RF: 7.18 J g-1 and UF: 7.34 J g-1) also showed lower values of gelatinization enthalpy. Freezing techniques were viable in facilitating the diffusion of α-amylase and reducing RS by up to 81%.

The role of self-reported and physiological stress in nocebo hyperalgesia.

Negative expectations can increase pain sensitivity, leading to nocebo hyperalgesia. However, the physiological and psychological factors that predispose individuals to this phenomenon are still not well understood. The present study examined whether stress induced by a social stressor affects nocebo hyperalgesia, and whether this effect is mediated by self-reported and physiological stress responses. We recruited 52 healthy participants (15 men) who were randomly assigned to either the Trier Social Stress Test (TSST) or a control condition (a friendly version of the TSST). Nocebo hyperalgesia was induced using negative suggestions combined with a validated pain conditioning paradigm. We assessed self-reported (anxiety and stress) and physiological (cortisol, alpha-amylase, heart rate, and skin conductance) responses to stress. Both groups exhibited significant nocebo hyperalgesia. The stress group showed higher levels of anxiety, self-reported stress, and cortisol levels compared to the control group while no significant differences were found in other physiological markers. The stress and control groups did not differ in the magnitude of nocebo hyperalgesia, but anxiety levels partially mediated the effects of the stress test on nocebo hyperalgesia. Our findings suggest that an external social stressor does not directly affect nocebo hyperalgesia, but that increased anxiety due to the stressor enhances its magnitude. Thus, it may be worthwhile to investigate whether reducing stress-related anxiety in clinical settings would help alleviate nocebo effects.

Phytoconstituents of Nymphaea rubra flowers and their anti-diabetic metabolic targets.

Nymphaea rubra (N. rubra) flowers are prevalent in subtropical regions for both dietary and traditional medicinal purposes, attributing to their beneficial properties in supporting overall health. This study first time provides descriptions of the antidiabetic and dyslipidemic properties employing STZ induced high fat diet fed diabetic rats and inhibition of α-amylase enzyme activity first by in vitro analyses, followed by a confirmatory in silico study to create a stronger biochemical rationale. Furthermore, in 3 T3-L1 cells, this extract promoted the suppression of adipogenesis. GC-MS investigation of the ethyl acetate fraction of ethanolic extract of N. rubra flowers revealed the presence of marker compounds of N. rubra, Nuciferine, and Apomorphine, which were the focus of molecular docking studies. The acquired concentrations of Nuciferine (22.39%) and 10, 11-dimethoxy-Apomorphine (1.47%) were detected. Together with other alkaloids identified by GC-MS analysis from this extract, mechanistically suggested that it might be caused by the synergistic impact of these bioactive chemicals. Molecular docking has been done to check the binding affinities of various isolated phytochemicals with HPAA, the dose-response effect of 100 mg/kg and 250 mg/kg of flower extract after 30 days showed a significant effect on body weight, food, water intake, serum insulin, FBG, OGTT, lipid profile, glycated haemoglobin, liver and kidney function test. Kidney histopathology results show a significant effect. These findings offer a strong foundation for the potential application of the ethyl acetate fraction of ethanolic extract from Nymphaea rubra flowers and its bioactive constituent in an in vivo system for the treatment and control of diabetes and its associated condition dyslipidemia.

Interactions between corn starch and lingonberry polyphenols and their effects on starch digestion and glucose transport.

This study investigated the interaction mechanism between corn starch (CS) and lingonberry polyphenols (LBP) during starch gelatinization, focusing on their effects on starch structure and physicochemical properties. Moreover, it explored the effect of this interaction on starch digestion and glucose transport. The results indicated that LBP interacted non-covalently with CS during starch gelatinization, disrupted the short-range ordered structure of starch, decreased gelatinization enthalpy of starch, and formed a dense network structure. Furthermore, the incorporation of LBP remarkably reduced the digestibility of CS. In particular, the addition of 10 % LBP decreased the terminal digestibility (C∞) from 77.87 % to 60.43 % and increased the amount of resistant starch (RS) by 21.63 %. LBP was found to inhibit α-amylase and α-glucosidase in a mixed manner. Additionally, LBP inhibited glucose transport in Caco-2 cells following starch digestion. When 10 % LBP was added, there was a 34.17 % decrease in glucose transport compared with starch digestion without LBP. This study helps establish the foundation for the development of LBP-containing starch or starch-based healthy foods and provides new insights into the mechanism by which LBP lowers blood glucose.