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Α-glucosidase inhibition can be useful in the management of carbohydrate-related diseases, especially type 2 diabetes mellitus. Therefore, in this study, a new series of 6-chloro-2-methoxyacridine bearing different aryl triazole derivatives were designed, synthesized, and evaluated as potent α-glucosidase inhibitors. The most potent derivative in this group was 7h bearing para-fluorine with IC 50 values of 98.0 ± 0.3 µM compared with standard drug acarbose (IC 50 value = 750.0 ± 10.5 μM). A kinetic study of compound 7h revealed that it is a competitive inhibitor against α-glucosidase. Molecular dynamic simulations of the most potent derivative were also executed and indicated suitable interactions with residues of the enzyme which rationalized the in vitro results., (© 2024. The Author(s).)

Isoxerophilusins A ( 1 ) and B ( 2 ), two unprecedented diterpene heterodimers biogenetically from ent -atisanes and abietanes, were isolated from the rhizomes of Isodon xerophilus . Their structures were determined by extensive spectroscopic analysis and single-crystal X-ray diffraction. Selective esterification of 1 generated 11 new derivatives. All derivatives showed excellent α -glucosidase inhibitory activity in comparison to acarbose. Compounds 12 and 13 demonstrated significant inhibition against α -glucosidase with IC 50 values of 4.92 and 3.83 μ M, respectively.

Six new phenylpropanoid glycosides ( 1 - 6 ), two new phenylethanol glycosides ( 7 and 8 ), one new phenylmethanol glycoside ( 9 ), three new phenylpropanoid dimers ( 10 - 12 ), two new phenylpropanoid-flavan-3-ol heterodimers ( 13 and 14 ), and six known relevant compounds ( 15 - 20 ) were isolated and identified from the well-liked edible and medicinal substance (the bark of Cinnamomum cassia (L.) J.Presl). The structures of these isolates were determined by using spectroscopic analyses, chemical methods, and quantum chemical calculations. Notably, compounds 4 - 9 were rare apiuronyl-containing glycosides, and compounds 13 and 14 were heterodimers of phenylpropanoids and flavan-3-ols linked through C-9″-C-8 bonds. The antioxidant and α-glucosidase inhibitory activities of all isolates were evaluated. Compounds 10 and 12 exhibited DPPH radical scavenging capacities with IC 50 values of 20.1 and 13.0 μM, respectively (vitamin C IC 50 value of 14.3 μM). In the ORAC experiment, all these compounds exhibited different levels of capacity for scavenging free radicals, and compound 10 displayed extraordinary free radical scavenging capacity with the ORAC value of 6.42 ± 0.01 μM TE/μM (EGCG ORAC value of 1.54 ± 0.02 μM TE/μM). Compound 12 also showed significant α-glucosidase inhibitory activity with an IC 50 of 56.3 μM (acarbose IC 50 of 519.4 μM).

A talented endophytic Streptomyces sp. PH9030 is derived from the medicinal plant Kadsura coccinea (Lem.) A.C. Smith. The undescribed naphthoquinone naphthgeranine G ( 5 ) and seven previously identified compounds, 6 - 12 , were obtained from Streptomyces sp. PH9030. The structure of 5 was identified by comprehensive examination of its HRESIMS, 1D NMR, 2D NMR and ECD data. The inhibitory activities of all the compounds toward α-glucosidase and their antibacterial properties were investigated. The α-glucosidase inhibitory activities of 5 , 6 , 7 and 9 were reported for the first time, with IC 50 values ranging from 66.4 ± 6.7 to 185.9 ± 0.2 μM, as compared with acarbose (IC 50 = 671.5 ± 0.2 μM). The molecular docking and molecular dynamics analysis of 5 with α-glucosidase further indicated that it may have a good binding ability with α-glucosidase. Both 9 and 12 exhibited moderate antibacterial activity against methicillin-resistant Staphylococcus aureus , with minimum inhibitory concentration (MIC) values of 16 μg/mL. These results indicate that 5 , together with the naphthoquinone scaffold, has the potential to be further developed as a possible inhibitor of α-glucosidase.

Starch is a polysaccharide produced exclusively through photosynthesis in plants and algae; however, is utilized as an energy source by most organisms, from microorganisms to higher organisms. In mammals and the germinating seeds of plants, starch is metabolized by simple hydrolysis pathways. Moreover, starch metabolic pathways via unique oligosaccharides have been discovered in some bacteria. Each organism has evolved enzymes responsible for starch metabolism that are diverse in their enzymatic properties. This review, focusing on eukaryotic α-glucosidases and bacterial α-glucoside-hydrolyzing enzymes, summarizes the structural aspects of starch-metabolizing enzymes belonging to glycoside hydrolase families 15, 31, and 77 and their application for oligosaccharide production., (© The Author(s) 2024. Published by Oxford University Press on behalf of Japan Society for Bioscience, Biotechnology, and Agrochemistry.)

Pueraria lobata (Willd.) Ohwi, known as kudzu and used as a "longevity powder" in China, is an edible plant which is rich in flavonoids and believed to be useful for regulating blood sugar and treating diabetes, although the modes of action are unknown. Here, a total of 53 flavonoids including 6 novel compounds were isolated from kudzu using multidimensional preparative liquid chromatography. The flavonoid components were found to lower blood sugar levels, promote urine sugar levels in mice, and reduce the urine volume. Molecular docking and in vitro assays suggested that the antidiabetic effect of kudzu was attributed to at least three targets: sodium-dependent glucose transporter 2 (SGLT2), protein tyrosine phosphatase-1B (PTP1B), and alpha-glucosidase (AG). This study suggests a possible mechanism for the antidiabetic effect that may involve the synergistic action of multiple active compounds from kudzu.

In this work, a novel series of N-phenylacetamide-1,2,3-triazole-indole-2-carboxamide derivatives 5a-n were designed by consideration of the potent α-glucosidase inhibitors containing indole and carboxamide-1,2,3-triazole-N-phenylacetamide moieties. These compounds were synthesized by click reaction and evaluated against yeast α-glucosidase. All the newly title compounds demonstrated superior potency when compared with acarbose as a standard inhibitor. Particularly, compound 5k possessed the best inhibitory activity against α-glucosidase with around a 28-fold improvement in the inhibition effect in comparison standard inhibitor. This compound showed a competitive type of inhibition in the kinetics. The molecular docking and dynamics demonstrated that compound 5k with a favorable binding energy well occupied the active site of α-glucosidase., (© 2024. The Author(s).)

In this study, 2(3),9(10),16(17),23(24)-tetrakis-[( N -methyl-(1-benzylpiperidin-4-yl)oxy)phthalocyaninato]zinc(II) iodide (ZnPc-2) was synthesized and characterized using spectral methods (FT-IR, 1 H-NMR, UV-Vis and mass spectroscopy). The interaction of ZnPc-2 with DNA was investigated by using the UV/Vis titrimetric method, thermal denaturation profile, agarose gel electrophoresis and molecular docking studies. Additionally, the antidiabetic activity of ZnPc-2 was revealed spectroscopically by studying α-amylase and α-glucosidase inhibition activities. The spectroscopic results indicated that ZnPc-2 effectively binds to calf thymus-DNA (CT-DNA) with a K b value of 7.5 × 10 4 M -1 and interacts with CT-DNA via noncovalent binding mode. Gel electrophoresis results also show that ZnPc-2 binds strongly to DNA molecules and exhibits effective nuclease activity even at low concentrations. Furthermore, docking studies suggest that ZnPc-2 exhibits a stronger binding tendency with DNA than the control compounds ethidium bromide and cisplatin. Consequently, due to its strong DNA binding and nuclease activity, ZnPc-2 may be suitable for antimicrobial and anticancer applications after further toxicological tests. Additionally, antidiabetic studies showed that ZnPc-2 had both α-amylase and α-glucosidase inhibition activity. Moreover, the α-glucosidase inhibitory effect of ZnPc-2 was approximately 3500 times higher than that of the standard inhibitor, acarbose. Considering these results, it can be said that ZnPc-2 is a moderate α-amylase and a highly effective α-glucosidase inhibitor. This suggests that ZnPc-2 may have the potential to be used as a therapeutic agent for the treatment of type 2 diabetes.

Introduction: The Bruguiera cylindrica L. is a mangrove plant that is typically found in coastal areas of Asia, including India. It has been known for its medicinal properties, which have been utilized for generations. For example, in Thailand, it has been used to treat wounds and diarrhoea, while in India, it has been effective in addressing diabetes, ulcers, and other health issues. This particular study sought to investigate the potential of B. cylindrica bark extract in reducing the symptoms of diabetes in rats., Methods: In this study, we examined the potential of B. cylindrica bark extract as an inhibitor of α-amylase and α-glucosidase enzymes in vitro. We also evaluated the effects of the extract and Metformin on rats fed high-fat diets and measured their lipid profiles and biochemical parameters. Furthermore, we conducted a network pharmacology analysis to identify proteins and pathways involved in the amelioration of diabetes., Results: Through metabolite profiling, we identified 58 compounds in B. cylindrica hydroalcoholic extract. These compounds include alkaloids, phenolics, flavonoids, and fatty acids. The extract was found to have a dose-dependent inhibition activity against α-amylase and α-glucosidase, with IC50 values similar to acarbose. In rats, oral administration of 200-400 mg/kg of B. cylindrica led to reduced blood glucose levels and normalized serum biochemical parameters., Conclusions: Bruguiera cylindrica bark may reduce blood sugar levels in rats with diabetes. The study found metabolites that interact with protein targets associated with different types of diabetes., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Royal Pharmaceutical Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

In the current study, a series of fluorine-substituted piperidine derivatives (1-8) has been synthesized and characterized by various spectroscopic techniques. In vitro and in vivo enzyme inhibitory studies were conducted to elucidate the efficacy of these compounds, shedding light on their potential therapeutic applications. To the best of our knowledge, for the first time, these heterocyclic structures have been investigated against α-glucosidase and cholinesterase enzymes. The antioxidant activity of the synthesized compounds was also assessed. Evaluation of synthesized compounds revealed notable inhibitory effects on α-glucosidase and cholinesterases. Remarkably, the target compounds (1-8) exhibited extraordinary α-glucosidase inhibitory activity as compared to the standard acarbose by several-fold. Subsequently, the potential antidiabetic effects of compounds 2, 4, 5, and 6 were validated using a STZ-induced diabetic rat model. Kinetic studies were also performed to understand the mechanism of inhibition, while structure-activity relationship analyses provided valuable insights into the structural features governing enzyme inhibition. Kinetic investigations revealed that compound 4 displayed a competitive mode of inhibition against α-glucosidase, whereas compound 2 demonstrated mixed-type behavior against AChE. To delve deeper into the binding interactions between the synthesized compounds and their respective enzyme targets, molecular docking studies were conducted. Overall, our findings highlight the promising potential of these densely substituted piperidines as multifunctional agents for the treatment of diseases associated with dysregulated glucose metabolism and cholinergic dysfunction., Competing Interests: Declaration of competing interest Hereby I declare that we have NO conflict of interest., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Background: Due to that the higher activity of nanozymes would bring outstanding performance for the nanozyme-based biosensing strategies, great efforts have been made by researchers to improve the catalytic activity of nanozymes, and novel nanozymes with high catalytic activity are desired. Considering the crucial role in controlling blood glucose level, strategies like colorimetric and chemiluminescence to monitor α-glucosidase are developed. However, multi-mode detection with higher sensitivity was insufficient. Therefore, developing triple-mode detection method for α-glucosidase based on great performance nanozyme is of great importance., Results: In this work, a novel nanozyme Cu-BCN was synthesized by loading Cu on boron doped carbon substrate g-C 3 N 4 and applied to the colorimetric-fluorescent-smartphone triple-mode detection of α-glucosidase. In the presence of H 2 O 2 , Cu-BCN catalyzed the generation of 1 O 2 from H 2 O 2 , 1 O 2 subsequently oxidized TMB to blue colored oxTMB. In the presence of hydroquinone (HQ), the ROS produced from H 2 O 2 was consumed, inhibiting the oxidation of TMB, which endows the possibility of colorimetric and visual on-site detection of HQ. Further, due to that the fluorescence of Mg-CQDs at 444 nm could be quenched by oxTMB, HQ could also be quantified through fluorescent mode. Since α-glucosidase could efficiently hydrolyze α-arbutin into HQ, the sensitive detection of α-glucosidase was realized. Further, colorimetric paper-based device (c-PAD) was fabricated for on-site α-glucosidase detection. The LODs for α-glucosidase via three modes were 2.20, 1.62 and 2.83 U/L respectively, high sensitivities were realized., Significance: The nanozyme Cu-BCN possesses higher peroxidase-like activity by doping boron to the substrate than non-doped Cu-CN. The proposed triple-mode detection of α-glucosidase is more sensitive than most previous reports, and is reliable when applied to practical sample. Further, the smartphone-based colorimetric paper-based analytical device (c-PAD) made of simple materials could also detect α-glucosidase sensitively. The smartphone-based on-site detection provided a convenient, instrument-free and sensitive sensing method for α-glucosidase., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Aim: The purpose of this study is to design and synthesize a series of novel chalcone amide α-glucosidase (AG) inhibitors ( L1-L10 ) based on virtual screening and molecular dynamics (MD) simulation. Materials & methods: Target compounds ( L1-L10 ) were synthesized from 2-hydroxyacetophenone and methyl 4-formylbenzoate. Results: In vitro activity test shows that most compounds have good AG inhibition. Specially, compound L4 (IC 50  = 8.28 ± 0.04 μM) had the best inhibitory activity, superior to positive control acarbose (IC 50  = 8.36 ± 0.02 μM). Molecular docking results show that the good potency of L4 maybe attributed to strong interactions between chalcone skeleton and active site, and the torsion of carbon nitrogen bond in amide group. Conclusion: Compound L4 maybe regard as a good anti-Type II diabetes candidate to preform further study.

Different natural products derived from plants have long been utilized as traditional herbal remedies to treat a variety of ailments and these substances have inspired the design, discovery and development of new pharmaceuticals. Andrographis paniculata is an annual plant that is frequently grown for therapeutic purposes in Southeast Asian countries. The A. paniculata Nees is an Indonesian natural plant that is thought to have antioxidant, anti-diabetic, anti-inflammatory and anti-hyperlipidemic properties. In this study, ultrasonic-assisted extraction (UAE) was used to optimize extraction conditions by varying time and amplitude. Furthermore, the UAE extract was evaluated for antioxidant activity utilizing 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), iron reducing antioxidant power (FRAP), and copper ion reducing antioxidant capacity (CUPRAC), as well as its anti-diabetic potential via α-glucosidase inhibition. Based on antioxidant activity with an IC 50 value of 73.71 ±0.28, extract B (extraction time 35 minutes and amplitude 65%) was considered to have optimum conditions for extraction. In addition, it was found that extract A. paniculata (extraction time 30 minutes and amplitude 60%) showed the most active inhibitory activity against α-glucosidase, with an IC 50 value of 0.87 ±0.003. The A. paniculata ethanolic leaf extract exhibits antioxidant and anti-diabetic properties.

In this study, a ligand fishing method for the screening of α-glucosidase inhibitors from Ginkgo biloba leaf was established for the first time using α-glucosidase immobilized on the magnetic metal-organic framework. The immobilized α-glucosidase exhibited enhanced resistance to temperature and pH, as well as good thermal stability and reusability. Two ligands, namely quercitrin and quercetin, were screened from Ginkgo biloba leaf and identified by ultra-high performance liquid chromatography-tandem mass spectrometry. The half-maximal inhibitory concentration values for quercitrin and quercetin were determined to be 105.69 ± 0.39 and 83.49 ± 0.79 µM, respectively. Molecular docking further confirmed the strong inhibitory effect of these two ligands. The proposed approach in this study demonstrates exceptional efficiency in the screening of α-glucosidase inhibitors from complex natural medicinal plants, thus exhibiting significant potential for the discovery of antidiabetic compounds., (© 2024 Wiley‐VCH GmbH.)

Glucose, the predominant carbohydrate in the human body, initiates nonenzymatic reactions in hyperglycemia, potentially leading to adverse biochemical interactions. This study investigates the interaction between glucose and Bovine Serum Albumin (BSA), along with the protective effects of Spirulina platensis PCC 7345 aqueous extract. Phycobiliproteins (phycocyanin, phycoerythrin, and allophycocyanin) in the extract were quantified using spectrophotometry. The extract's anti-glycation potential was assessed by analyzing its effects on albumin glycation, fluorescent advanced glycation end products (AGEs), thiol group oxidation, and β-amyloid structure generation. Additionally, its antidiabetic potential was evaluated by measuring α-amylase and α-glucosidase enzyme inhibition. Results indicate that the Spirulina extract significantly mitigated ketoamine levels, fluorescence, and protein-carbonyl production induced by glucose, demonstrating a 67.81 % suppression of AGE formation after 28 days. Moreover, it effectively inhibited amyloid formation in BSA cross-linkages. These findings suggest the potential of S. platensis as an anti-glycation and antidiabetic agent, supporting its consideration for dietary inclusion to manage diabetes and associated complications., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

Three new oleanane-type triterpene saponins, named camphanosides A-C (1-3), along with five known compounds, chikusetsusaponin IVa (4), spinasaponin A 28-O-glucoside (5), (-)-epicatechin (6), (-)-epicatechin 3-O-gallate (7), and (-)-epigallocatechin 3-O-gallate (8) were isolated from the leaves Camellia phanii Hakoda & Ninh. Their structures were established by 1D and 2D-NMR and mass spectral analysis and chemical methods. Moreover, compounds 1-5 were also evaluated for α-glucosidase inhibitory activity. Compounds 1-3 exhibited moderate α-glucosidase inhibitory activity with IC 50 values of 230.7±18.0, 251.4±22.7, and 421.4±25.6 μM, respectively., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

Mediterranean saltbush Atriplex halimus L. (Amaranthaceae) from different bioclimatic arid zones (ten wild populations) were studied. Phenols contents, flavonoids, flavonols, tannins and anthocyanins were determined and then tested for their antioxidants, antidiabetic and anti-acetylcholinesterase (AChE) activities. Levels of total polyphenols including flavonoids and flavonols, tannins and anthocyanins were high and varied significantly among analyzed populations. Nine phenolic acids and four flavonoids were identified for the first time in the methanolic fraction and quantified by liquid high-performance chromatography system HPLC (DAD). All extracts showed a substantial antioxidant activity, as assessed by DPPH assay (1,1-diphenyl-2-picrylhydrazyl free radical) (IC 50DPPH =147.3for population of Seliena), Ferric Reducing Antioxidant Power (FRAP; IC 50FRAP =3.2 for populations of Sousse and Kairouan), and Chelation Fer test (IC 50FerCh =1.5 μg/mL for populations of El-hamma and Mednine). Atriplex halimus possessed a high inhibitory effect against α-amylase activity (up to 2.6 mg ACE/gE), a moderate activity for α-glucosidase (up to 91.0 mg ACE/gE) and AChE (up to 147.2 μg/mL) compared to standard. The analyzed populations were isolated and subdivided into three distinct groups, without any bioclimatic structuration. Enzymatic activities seem to be associated with the presence, in plant extracts, of other classes of compounds then phenols such as terpenes, sterols, saponins, coumarins and carotenoids., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

In this study, bioactive compounds were isolated and characterized from the leaves and root-barks extracts of S.latifolius, with subsequent in vitro experimental investigations for antihyperglycemic potentials on α-amylase and α-glucosidase enzymes. Thirteen bioactive compounds were identified, including 10-Hydroxystrictosamide (2) and Quinovic acid-3-O-α-L-rhamnosyl-28-O-β-d-glucopyranosyl ester (8), using chromatographic, nuclear magnetic resonance spectroscopy (NMR), and mass spectrometry (MS) techniques. Experimental assays revealed that compounds 1-4 exhibited potent inhibition of α-amylase and α-glucosidase, with compound 2 demonstrating the most potent α-amylase inhibition (IC 50 value of 0.52 ± 0.003 μg/mL). Compound 8 showed a lower IC 50 value (0.098 ± 0.016 μg/mL) against α-glucosidase compared to compound 2 and acarbose. Synergistic effects among the compounds could enhance their inhibitory actions on the enzymes, positioning them as potential anti-hyperglycemia agents. Compound 2 displayed the highest binding affinity (-7.970 kcal/mol) when docked against α-amylase (PDB ID: 2QV4), comparable to acarbose (-8.515 kcal/mol). It also ranked among the top ligands against α-glucosidase (PDB ID 3TOP), although compound 13 and acarbose had higher docking scores. All compounds exhibited ideal ADMET properties, suggesting good bioavailability and low toxicity. In conclusion, the isolated compounds exhibit promising antihyperglycemic potential and favourable safety profiles for further exploration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Introduction: Sicklepod [Cassia obtusifolia L. syn Senna obtusifolia (L.) H.S. Irwin & Barneby, Fabaceae] sprouts are promising ingredients with health-promoting benefits. Notwithstanding, the pharmacologically active compounds in sicklepod sprouts have not been studied or analysed in detail., Objective: This study aimed to isolate and structurally identify phytochemicals showing α-glucosidase inhibitory activity in sicklepod sprouts and simultaneously quantify the compounds in the sprouts to determine the optimal cultivation method and germination time to maximise active compounds., Method: A simultaneous high-performance liquid chromatography-ultraviolet (HPLC-UV) method with high sensitivity and accuracy was developed and used to analyse time-dependent changes in anthraquinone content during sicklepod germination., Results: Thirteen anthraquinones were isolated and identified, of which six-chrysoobtusin, emodin, 1-O-methyl-2-methoxychrysophanol, 7-O-methylobtusin, chrysophanol, and physcion-showed moderate α-glucosidase inhibitory activity. The maximum content of anthraquinones in a sprout was observed on Day 5 under both light and dark conditions., Conclusion: The findings of this study revealed that sicklepod sprouts which are promising functional food materials contain a variety of anthraquinones., (© 2024 John Wiley & Sons Ltd.)

One new iridoid namely rupesin F ( 1 ) together with four known ones ( 2 - 5 ) were isolated from the roots of Valeriana jatamansi Jones. The structures were established using spectroscopic methods (1D and 2D NMR including HSQC, HMBC, COSY and NOESY) and by comparison with previously published literature data. The isolated compounds 1 and 3 exhibited strong α-glucosidase inhibition activity with IC 50 values of 10.13 ± 0.11 and 9.13 ± 0.03 μg/mL, respectively. This study enriched the chemical diversity of metabolites and provides a direction for the development of antidiabetic agents.

Opuntia ficus-indica fruit (OFI) is rich in bioactive compounds, which can promote human health. In this work, the purified OFI extract was prepared from OFI and its bioactivities were investigated. Xanthine oxidase (XOD) and α-glucosidase (α-Glu) inhibitors of the purified OFI extract were screened and identified by bio-affinity ultrafiltration combined with UPLC-QTRAP-MS/MS technology. The inhibitory effect of these inhibitors on enzymes were verified, and the potential mechanism of action and binding sites of inhibitors with enzymes were revealed based on molecular docking. The results showed that the total phenolic content of the purified OFI extract was 355.03 mg GAE/g DW, which had excellent antioxidant activity. Additionally, the extract had a certain inhibitory effect on XOD (IC 50  = 199.00 ± 0.14 µg/mL) and α-Glu (IC 50  = 159.67 ± 0.01 µg/mL). Seven XOD inhibitors and eight α-Glu inhibitors were identified. Furthermore, XOD and α-Glu inhibition experiments in vitro confirmed that inhibitors such as chlorogenic acid, taxifolin, and naringenin had significant inhibitory effects on XOD and α-Glu. The molecular docking results indicated that inhibitors could bind to the corresponding enzymes and had strong binding force. These findings demonstrate that OFI contains potential substances for the treatment of hyperuricemia and hyperglycemia., (© 2024 Institute of Food Technologists.)

Viburnum luzonicum Rolfe is widely used in China as folk medicine. The bioactivity evaluation indicated that the n -BuOH fraction of V. luzonicum leaves (VLLB) could significantly inhibit α ‑amylase and α -glucosidase. In order to clarify its active constituents, the phytochemical analysis on VLLB was first performed using HPLC-QTOF-MS/MS, and three new phenolic compounds, viburosides A-C ( 1 - 3 ), along with seven known analogues ( 4 - 10 ) were isolated through preparative HPLC. The undescribed compounds were determined by extensive spectroscopic analyses ( 1 H and 13 C NMR, HSQC, HMBC, HRESIMS, and ORD) and enzymatic hydrolysis. In the in vitro enzyme assays, compounds 1 - 8 showed potent α ‑amylase and α -glucosidase inhibitory activities. The enzymatic kinetics and molecular docking of the strongest inhibitors 2 and 3 against the corresponding target enzyme were also performed.

From the EtOAc extract of the wood of the stems of Taxotrophis ilicifolius (Moraceae), two new secondary metabolites, named taxotrophises A ( 1 ) and B ( 2 ), were isolated, together with five known compounds ( 3 - 7 ). Their chemical structures have been elucidated by extensive NMR spectroscopic analysis. All isolated compounds have been evaluated for α -glucosidase inhibitory activity. In the present work, compounds 1 and 4 showed the strongest α -glucosidase inhibitory activity with IC 50 values of 6.5 and 1.5  μ M, respectively, and stronger than that of a positive control, acarbose (IC 50 ; 214.5  μ M).

This study describes the design, synthesis, and evaluation of a novel series of phenylthiosemicarbazide-phenoxy-1,2,3-triazole-N-phenylacetamide derivatives (7a-l) as dual inhibitors of α-glucosidase and protein tyrosine phosphatase 1-B (PTB-1B). The latter enzymes are two important targets in the treatment of type 2 diabetes. The in vitro obtained data demonstrated that all title compounds 7a-l were more potent than the standard inhibitor acarbose against α-glucosidase while only four derivatives (7a, 7g, 7h, and 7h) were more potent than the standard inhibitor suramin against PTP-1B. Furthermore, these data showed that the most potent α-glucosidase inhibitor was compound 7i, with sixfold higher inhibitory activity than acarbose, and the most potent PTP-1B inhibitor was compound 7a with 3.5-fold higher inhibitory activity than suramin. Kinetic studies of compounds 7i and 7a revealed that they inhibited their target enzymes in a competitive mode. The docking study demonstrated that compounds 7i and 7a well occupied the active site pockets of α-glucosidase and PTP-1B, respectively. In silico pharmacokinetic and toxicity assays of the most potent compounds were performed, and the obtained results were compared with those of the standard inhibitors., (© 2024 Deutsche Pharmazeutische Gesellschaft.)

Diabetes is a common lifestyle disorder found in populations of different age groups. Maltase-glucoamylase catalyses the release of the glucose molecule in the final enzymatic reaction of starch digestion; therefore, inhibition of maltase-glucoamylase is one of the approaches in the development of therapeutics for diabetes. Citrullus colocynthis is commonly recommended in Ayurveda for the treatment of diabetes. The current study applied a structure-based drug design approach to repurpose the phytochemicals of Citrullus colocynthis to identify potential inhibitors for maltase-glucoamylase. 70 phytochemicals of Citrullus colocynthis were screened against maltase-glucoamylase and top 5 molecules 8-p-hydroxybenzylisovitexin, isoorientin, cucurbitacin B, cucurbitacin E, and cucurbitacin I with significant binding energy of -10 kcal/mol, -9.9 kcal/mol, -9.6 kcal/mol, -9.2 kcal/mol, and -7.7 kcal/mol were identified. Furthermore, MMGBSA, pharmacokinetics properties and toxicity prediction were performed on the five identified molecules and top 3 molecules were selected for molecular dynamics (MD) simulation. It was observed from the structural flexibility and dynamic behaviour of the systems that conformational changes were noticed in the complexes as compared to its native state, which suggests that the 3 molecules, namely 8-p-hydroxybenzylisovitexin, isoorientin, and cucurbitacin I of Citrullus colocynthis may act as inhibitors for maltase-glucoamylase.Communicated by Ramaswamy H. Sarma.

In this study, four undescribed bibenzyl derivatives (1-4), together with seven known compounds (5-11) were isolated from the aerial parts of Dendrobium officinale. Their chemical structures were determined to be (7'S,8'S) -9''-acetyldendrocandin U (1), (7'S,8'S) -4'-methoxydendrocandin T (2), (7'R,8'S) -dendrocandin B (3), (1S,2R) -5'''-methoxydendrofindlaphenol C (4) by analyzing of the spectroscopic data including HR-ESI-MS, 1D-, and 2D-NMR spectra. The absolute configurations of compounds 1-4 were determined by the electronic circular dichroism (ECD) spectra. Compounds 1-3, 5, 10 and 11 inhibited α-glucosidase with the IC 50 values ranging from 56.3 to 165.3 μM, compounds 1-3, 5, 7-10 inhibited α-amylase with the IC 50 values ranging from 65.2 to 177.6 μM., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

A bio-guided isolation was applied to the Vietnamese lichen Roccella montagnei based on alpha-glucosidase inhibition. Six compounds were isolated and structurally elucidated, including a new ortho depside, montagneside A (1), together with five known compounds, sekikaic acid (2), lanost-7-en-3β-ol (3), ethyl orsellinate (4), D-montagnetol (5), and D-erythrin (6). Their chemical structures were identified by extensive 1D and 2D NMR analysis, high-resolution mass spectroscopy, and comparisons with those reported in the literature. D-Erythrin (6), a major component, was selected for further modification using Smiles rearrangement. Three erythritol derivatives 6a-6c were synthesized. Compounds 1-3, 6, and 6a-6c were evaluated for alpha-glucosidase inhibition. Compounds 2 and 6a-6c showed significant alpha-glucosidase inhibition with IC 50 values ranging from 7.9 to 149 μM, respectively. Molecular docking was applied to the most active compound 6a to clarify the inhibitory mechanism., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

Five pairs of new merosesquiterpenoid enantiomers, named dauresorcinols A-E (1-5), were isolated from the leaves of Rhododendron dauricum. Their structures were elucidated by comprehensive spectroscopic data analysis, quantum chemical calculations, Rh 2 (OCOCF 3 ) 4 -induced ECD, and single-crystal X-ray diffraction analysis. Dauresorcinols A (1) and B (2) possess two new merosesquiterpene skeletons bearing an unprecedented 2,6,7,10,14-pentamethyl-11-oxatetracyclo[8.8.0.0 2,7 .0 12,17 ]octadecane and a caged 15-isohexyl-1,5,15-trimethyl-2,10-dioxatetracyclo[7.4.1.1 11,14 .0 3,8 ]pentadecane motif, respectively. Plausible biosynthetic pathways of 1-5 are proposed involving key oxa-electrocyclization and Wagner-Meerwein rearrangement reactions. (+)/(-)-1 and 3-5 showed potent α-glucosidase inhibitory activity, 3 to 22 times stronger than acarbose, an antidiabetic drug targeting α-glucosidase. Docking results provide a basis to design and develop merosesquiterpenoids as potent α-glycosidase inhibitors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Quantitative analysis of Rumex nepalensis var. remotiflorus revealed that its roots contain rich anthraquinones, which has emodin, chrysophanol, and physcion contents of up to 0.30, 0.67, and 0.98 mg/g, respectively. Further phytochemical study led to the isolation and purification of seven undescribed phenolic constituents, including one flavan derivative with a 13-membered ring, polygorumin A (1), two dianthrone glucosides, polygonumnolides F and G (2, 3), two diphenylmethanones, rumepalens A and B (4, 5), and a pair of epimeric oxanthrone C-glucosides, rumejaposides K and L (6a, 6b) from the roots of R. nepalensis var. remotiflorus. Furthermore, 1 undescribed natural product, 1-β-D-glucoside-6'-[(2E)-3-(4-hydroxy-3-methoxyphenyl)-2-propenoate]-3-hydroxy-5-methylphenyl (19), and 21 known phenolic compounds were obtained from the aforementioned plant for the first time. Their structures were elucidated through extensive spectroscopic data analysis. Notably, compounds 1, 4-5, and 7-9 exhibited inhibitory activity on α-glucosidase with IC 50 values ranging from 1.61 ± 0.17 to 32.41 ± 0.87 μM. In addition, the isolated dianthrone, chrysophanol bianthrone (14), showed obvious cytotoxicity against four human cancer cell lines (HL-60, SMMC-7721, A-549, and MDA-MB-231) with IC 50 values ranging from 3.81 ± 0.17 to 35.15 ± 2.24 μM. In silico target prediction and molecular docking studies demonstrated that the mechanism of the anticancer activity of 14 may be related to the interaction with protein kinase CK2., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ying-Jun Zhang reports financial support was provided by Ministry of Science and Technology of the People's Republic of China. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

In diabetes mellitus, amylase and glucosidase enzymes are the primary triggers. The main function of these enzymes is to break macromolecules into simple sugar units, which directly affect blood sugar levels by increasing blood permeability. To overcome this metabolic effect, there is a need for a potent and effective inhibitor capable of suppressing the enzymatic conversion of sugar macromolecules into their smaller units. Herein, we reported the discovery of a series of substituted triazolo[4,3-b][1,2,4]triazine derivatives as α-glucosidase and α-amylase inhibitors. All target compounds demonstrated significant inhibitory activities against α-glucosidase and α-amylase enzymes compared with acarbose as the positive control. The most potent compound 10k, 2-[(6-phenyl-[1,2,4]triazolo[4,3-b][1,2,4]triazin-3-yl)thio]-N-[4-(trifluoromethyl)phenyl]acetamide, demonstrated IC 50 values of 31.87 and 24.64 nM against α-glucosidase and α-amylase enzymes, respectively. To study their mechanism of action, kinetic studies were also done, which determined the mode of inhibition of both enzymes. Molecular docking was used to confirm the binding interactions of the most active compounds., (© 2024 Deutsche Pharmazeutische Gesellschaft.)

Pomegranate peel-derived extracellular nanovesicles(PPENs) were isolated and purified by ultra-high speed centrifugation and sucrose density gradient centrifugation. Their morphology and structure were characterized. In vitro α-glucosidase inhibition assay and model test of insulin resistance(IR) in HepG2 cells showed that PPENs had good anti-diabetic activity. The IC_(50) value of α-glucosidase inhibition was(35.3±1.1) μg·mL~(-1), significantly better than the positive drug acarbose. At a concentration of 100 μg·mL~(-1), PPENs could increase the glucose absorption of IR cells significantly. Lipidome, proteome, and metabolite analysis of PPENs were performed using chromatography-mass spectrometry. MicroRNA(miRNA) sequences were identified, and target genes of miRNA were predicted. The analysis results indicated that PPENs contained abundant lipids and transport proteins, providing a material basis for the transportation and distribution of PPENs in tissue. Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analysis suggested that lipids and miRNAs may be the key components of PPENs to exert anti-diabetic activity.

This study focuses on synthesizing a new series of isoxazolinyl-1,2,3-triazolyl-[1,4]-benzoxazin-3-one derivatives 5a - 5o . The synthesis method involves a double 1,3-dipolar cycloaddition reaction following a "click chemistry" approach, starting from the respective [1,4]-benzoxazin-3-ones. Additionally, the study aims to evaluate the antidiabetic potential of these newly synthesized compounds through in silico methods. This synthesis approach allows for the combination of three heterocyclic components: [1,4]-benzoxazin-3-one, 1,2,3-triazole, and isoxazoline, known for their diverse biological activities. The synthesis procedure involved a two-step process. Firstly, a 1,3-dipolar cycloaddition reaction was performed involving the propargylic moiety linked to the [1,4]-benzoxazin-3-one and the allylic azide. Secondly, a second cycloaddition reaction was conducted using the product from the first step, containing the allylic part and an oxime. The synthesized compounds were thoroughly characterized using spectroscopic methods, including 1 H NMR, 13 C NMR, DEPT-135, and IR. This molecular docking method revealed a promising antidiabetic potential of the synthesized compounds, particularly against two key diabetes-related enzymes: pancreatic α-amylase, with the two synthetic molecules 5a and 5o showing the highest affinity values of 9.2 and 9.1 kcal/mol, respectively, and intestinal α-glucosidase, with the two synthetic molecules 5n and 5e showing the highest affinity values of -9.9 and -9.6 kcal/mol, respectively. Indeed, the synthesized compounds have shown significant potential as antidiabetic agents, as indicated by molecular docking studies against the enzymes α-amylase and α-glucosidase. Additionally, ADME analyses have revealed that all the synthetic compounds examined in our study demonstrate high intestinal absorption, meet Lipinski's criteria, and fall within the required range for oral bioavailability, indicating their potential suitability for oral drug development.

Benzene sulfonamides are an important biological substituent for several activities. In this study, hybridization of benzene sulfonamide with piperazine derivatives were investigated for their antioxidant capacity and enzyme inhibitory potencies. Six molecules were synthesized and characterized. DPPH, ABTS, FRAP, CUPRAC, chelating and phosphomolybdemum assays were applied to evaluate antioxidant capacities. Results show that compounds have high antioxidant capacity and compound 4 has the best antioxidant activity among them. Compound 4 has higher antioxidant activity than references for FRAP (IC 50 : 0.08 mM), CUPRAC (IC 50 : 0.21 mM) and phosphomolybdenum (IC 50 : 0.22 mM) assays. Besides this, compound 4 has moderate DPPH and ABTS antioxidant capacity. Furthermore, enzyme inhibition activities of these molecules were investigated against AChE, BChE, tyrosinase, α -amylase and α -glucosidase enzymes. It was revealed that all compounds have good enzyme inhibitory potential except for α -amylase enzyme. The best inhibitory activities were observed for AChE with compound 5 the same value (IC 50 : 1.003 mM), for BChE with compounds 2 and 5 the same value (IC 50 : 1.008 mM), for tyrosinase compound 4 (IC 50 : 1.19 mM), and for α -glucosidase with compound 3 (IC 50 : 1.000 mM). Docking studies have been conducted with these molecules, and the results correlate well with the inhibitory assays., (© 2024 Walter de Gruyter GmbH, Berlin/Boston.)

Spermacoce alata Aubl. is widely available in the market as traditional Chinese medicine and animal feed, due to its properties of clearing heat and treating malaria and its high-protein and crude fiber content. In this study, the essential oil of S. alata was obtained through hydrodistillation. GC-MS and GC-FID methods were used to identify the chemical components and their relative abundance. Furthermore, the antioxidant capacity was measured using DPPH, ABTS, and FRAP assays, and the inhibitory effects of acetylcholinesterase, α-glucosidase, and β-lactamase were also evaluated. A total of 67 compounds were identified, with the major constituents being palmitic acid (30.74%), linoleic acid (16.13%), and phenylheptatriyne (8.07%). The essential oil exhibited moderate antioxidant activity against DPPH (IC 50 > 10 mg/mL), while the IC 50 value for the ABTS assay was 3.84 ± 2.12 mg/mL and the FRAP assay value was 87.22 ± 12.22 µM/g. Additionally, the essential oil showed moderate anti-acetylcholinesterase activity (IC 50 = 286.0 ± 79.04 μg/mL), significant anti-α-glucosidase activity (IC 50 = 174.7 ± 13.12 μg/mL), and potent anti-β-lactamase activity (IC 50 = 37.56 ± 3.48 μg/mL). The results suggest that S. alata has the potential for application in pharmacology, warranting further exploration and investigation.

Phyllanthus emblica Linn. (PE) fresh fruits contain high concentrations of polyphenolics, of which free and bound phenolics are rich in biological activities. In this study, the inhibitory activity and mechanism of PEFP and PEBP on α-glucosidase (α-GLU) were investigated using spectroscopic techniques, kinetic analysis, and molecular docking. The results showed that 13 PEFP and 12 PEBP were identified by UPLC-MS/MS analysis, and Bis-HHDP-hexose and castalagin (vesgalagin) were found for the first time in PE fresh fruits. Kinetic analysis of enzyme inhibition showed that a mixture of free and bound phenolics inhibited α-GLU, and the effect of the conformational relationship of PEFP and PEBP with α-GLU on hypoglycemia was further explored by fluorescence quenching, circular dichroism (CD) spectroscopy, and molecular docking analysis. The findings demonstrated the inhibitory activity and mechanism of free and bound phenolics on α-GLU and provided a theoretical basis for PE polyphenolics as α-GLU inhibitors for hypoglycemia.

Glycoside hydrolases (glycosidases) take part in myriad biological processes and are important therapeutic targets. Competitive and mechanism-based inhibitors are useful tools to dissect their biological role and comprise a good starting point for drug discovery. The natural product, cyclophellitol, a mechanism-based, covalent and irreversible retaining β-glucosidase inhibitor has inspired the design of diverse α- and β-glycosidase inhibitor and activity-based probe scaffolds. Here, we sought to deepen our understanding of the structural and functional requirements of cyclophellitol-type compounds for effective human α-glucosidase inhibition. We synthesized a comprehensive set of α-configured 1,2- and 1,5a-cyclophellitol analogues bearing a variety of electrophilic traps. The inhibitory potency of these compounds was assessed towards both lysosomal and ER retaining α-glucosidases. These studies revealed the 1,5a-cyclophellitols to be the most potent retaining α-glucosidase inhibitors, with the nature of the electrophile determining inhibitory mode of action (covalent or non-covalent). DFT calculations support the ability of the 1,5a-cyclophellitols, but not the 1,2-congeners, to adopt conformations that mimic either the Michaelis complex or transition state of α-glucosidases., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

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., (© 2024 Wiley Periodicals LLC.)

The flowers of Edgeworthia gardneri are used as herbal tea and medicine to treat various metabolic diseases including hyperglycemia, hypertension, and hyperlipidemia. This paper investigate the chemical constituents and biological activities of ethanolic extract and its different fractions from E. gardneri flowers. Firstly, the E. gardneri flowers was extracted by ethanol-aqueous solution to obtain crude extract (CE), which was subsequently fractionated by different polar organic solution to yield precipitated crystal (PC), dichloromethane (DCF), ethyl acetate (EAF), n-butanol (n-BuF), and residue water (RWF) fractions. UHPLC-ESI-HRMS/MS analysis resulted in the identification of 25 compounds, and the main compounds were flavonoids and coumarins. The precipitated crystal fraction showed the highest phenolic and flavonoid contents with 344.4 ± 3.38 mg GAE/g extract and 305.86 ± 0.87 mg RE/g extract. The EAF had the strongest antioxidant capacity and inhibitory effect on α-glucosidase and pancreatic lipase with IC 50 values of 126.459 ± 7.82 and 23.16 ± 0.79 µg/mL. Besides, both PC and EAF significantly regulated the glucose and lipid metabolism disorders by increasing glucose consumption and reducing TG levels in HepG2 cells. Molecular docking results suggested that kaempferol-3-O-glucoside and tiliroside had good binding ability with enzymes, indicating that they may be potential α-glucosidase and pancreatic lipase inhibitors. Therefore, the E. gardneri flowers could be served as a bioactive agent for the regulation of metabolic disorders., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The preliminary α-glucosidase inhibitory activity of the methanol extract of the leaves of Sandoricum koetjape Merr. exhibited promising results. The leaves was extracted with methanol to obtain the methanol extract that was continuedly partitioned with hexane and ethyl acetate. Those fractions were further purified by various chromatographic techniques. The isolation of the potent fractions furnished two new cycloartane-type triterpenoids (1 and 2) along with ten known compounds (3-12). Their chemical structures were unambiguously established by interpretation of NMR (1 D & 2 D) and high-resolution electrospray ionization mass spectrometry (HRESIMS) data. Furthermore, the configurations of two new compounds were determined by using NOESY spectrum as well as comparing their NMR data to the reference. These compounds were evaluated against α-glucosidase. All tested compounds revealed potent activity with IC 50 value in the range of 2.17-49.2 µM compared to that of acarbose (IC 50 100.6 µM). Compound 10 showed the lowest IC 50 value. This compound was reported as a mixed-type inhibitor. Compound 3 possessed the second strong activity with an IC 50 value of 14.0 μM and was further investigated on kinetic analysis which revealed as a mixed-type inhibitor with K i and K i ' values of 59.1 and 155.2 μM, respectively., (© 2024. The Author(s) under exclusive licence to The Japanese Society of Pharmacognosy.)

The objective of this study was to investigate the impact of anthocyanin-rich black currant extract (BCE) on the structural properties of starch and the inhibition of glycosidases, gathering data and research evidence to support the use of low glycemic index (GI) foods. The BCE induced a change in the starch crystal structure from A-type to V-type, resulting in a drop in digestibility from 81.41 % to 65.57 %. Furthermore, the inhibitory effects of BCE on glycosidases activity (α-glucosidase: IC 50  = 0.13 ± 0.05 mg/mL and α-amylase: IC 50  = 2.67 ± 0.16 mg/mL) by inducing a change in spatial conformation were confirmed through in vitro analysis. The presence of a 5'-OH group facilitated the interaction between anthocyanins and receptors of amylose, α-amylase, and α-glucosidase. The glycosyl moiety enhanced the affinity for amylose yet lowered the inhibitory effect on α-amylase. The in vivo analysis demonstrated that BCE resulted in a reduction of 3.96 mM·h in blood glucose levels (Area Under Curve). The significant hypoglycemic activity, particularly the decrease in postprandial blood glucose levels, highlights the potential of utilizing BCE in functional foods for preventing diabetes., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2024. Published by Elsevier B.V.)

Introduction: Nymphaea rubra belongs to the Nymphaea family and is regarded as a vegetable used in traditional medicine to cure several ailments. These species are rich in phenolic acid, flavonoids, and hydrolysable tannin., Objective: This study aimed to assess the biological activities of Nymphaea rubra flowers (NRF) and leaves (NRL) by identifying and quantifying their polyphenolic compounds using ultra-performance liquid chromatography coupled to quadrupole cyclic ion mobility time-of-flight mass spectrometry (UHPLC-Q-cIM-TOF-MS) and triple quadrupole mass spectrometry (UHPLC-TQ-MS)., Methodology: NRF and NRL powder was extracted with methanol and fractionated using hexane, ethylacetate, and water. Antioxidant and α-glucosidase, and tyrosinase enzyme inhibitory activities were evaluated. The polyphenolic components of NRF and NRL were identified and quantified using UHPLC-Q-cIM-TOF-MS and UHPLC-TQ-MS. The method was validated using linearity, precision, accuracy, limit of detection (LOD), and lower limit of quantification (LLOQ)., Results: Bioactive substances and antioxidants were highest in the ethylacetate fraction of flowers and leaves. Principal component analysis showed how solvent and plant components affect N. rubra's bioactivity and bioactive compound extraction. A total of 67 compounds were identified, and among them 21 significant polyphenols were quantified. Each calibration curve had R 2  > 0.998. The LOD and LLOQ varied from 0.007 to 0.09 μg/mL and from 0.01 to 0.1 μg/mL, respectively. NRF contained a significant amount of gallic acid (10.1 mg/g), while NRL contained abundant pentagalloylglucose (2.8 mg/g)., Conclusion: The developed method is simple, rapid, and selective for the identification and quantification of bioactive molecules. These findings provide a scientific basis for N. rubra's well-documented biological effects., (© 2024 John Wiley & Sons Ltd.)

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 5O 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., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

The process of developing novel compounds/drugs is arduous, time-intensive, and financially burdensome, characterized by a notably low success rate and relatively high attrition rates. To alleviate these challenges, compound/drug repositioning strategies are employed to predict potential therapeutic effects for DrugBank-approved compounds across various diseases. In this study, we devised a computational and enzyme inhibitory mechanistic approach to identify promising compounds from the pool of DrugBank-approved substances targeting Diabetes Mellitus (DM). Molecular docking analyses were employed to validate the binding interaction patterns and conformations of the screened compounds within the active site of α-glucosidase. Notably, Asp352 and Glu277 participated in interactions within the α-glucosidase-ligand complexes, mediated by conventional hydrogen bonding and van der Waals forces, respectively. The stability of the docked complexes (α-glucosidase-compounds) was scrutinized through Molecular Dynamics (MD) simulations. Subsequent in vitro analyses assessed the therapeutic potential of the repositioned compounds against α-glucosidase. Kinetic studies revealed that "Forodesine" exhibited a lower IC 50 (0.24 ± 0.04 mM) compared to the control, and its inhibitory pattern corresponds to that of competitive inhibitors. In-depth in silico secondary structure content analysis detailed the interactions between Forodesine and α-glucosidase, unveiling significant alterations in enzyme conformation upon binding, impacting its catalytic activity. Overall, our findings underscore the potential of Forodesine as a promising candidate for DM treatment through α-glucosidase inhibition. Further validation through in vitro and in vivo studies is imperative to confirm the therapeutic benefits of Forodesine in conformational diseases such as DM., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Diabetes mellitus is one of the top ten causes of death worldwide, accounting for 6.7 million deaths in 2021, and is one of the most rapidly growing global health emergencies of this century. Although several classes of therapeutic drugs have been invented and applied in clinical practice, diabetes continues to pose a serious and growing threat to public health and places a tremendous burden on those affected and their families. The strategy of reducing carbohydrate digestibility by inhibiting the activities of α-glucosidase and α-amylase is regarded as a promising preventative treatment for type 2 diabetes. In this study, we investigated the dual inhibitory effect against two polysaccharide hydrolytic enzymes of flavonoid derivatives from an in-house chemical database. By combining molecular docking and structure-activity relationship analysis, twelve compounds with docking energies less than or equal to - 8.0 kcal mol -1 and containing required structural features for dual inhibition of the two enzymes were identified and subjected to chemical synthesis and in vitro evaluation. The obtained results showed that five compounds exhibited dual inhibitory effects on the target enzymes with better IC 50 values than the approved positive control acarbose. Molecular dynamics simulations were performed to elucidate the binding of these flavonoids to the enzymes. The predicted pharmacokinetic and toxicological properties suggest that these compounds are viable for further development as type 2 diabetes drugs., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

α-Glucosidase is one of the therapeutic approaches for treating type 2 diabetes mellitus. Almost 95 % of diabetes patients worldwide have been diagnosed with type 2 diabetes, resulting in 1.5 million fatalities each year. Newly synthesized oxazole-based tanshinone IIA derivatives (1a-n) were designed and evaluated for their inhibitory activity against α-glucosidase enzyme. Eight compounds (1a-d, 1f-g, 1j, and 1m) demonstrated excellent inhibition with IC 50 values ranging from 0.73 ± 0.11 to 9.46 ± 0.57 μM as compared to tanshinone IIA (IC 50  = 11.39 ± 0.77 μM) and standard acarbose (IC 50  = 100.00 ± 0.95 μM). Among this series, 1j bearing two hydroxyls group over the phenyl ring was identified as the most potent α-glucosidase inhibitor with IC 50 value of 0.73 ± 0.11 μM. Molecular docking simulations were done for the most active compound to identify important binding modes responsible for inhibition activity of α-glucosidase. In addition, the kinetic study was also performed to understand the mode of inhibition., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Warinthorn Chavasiri reports financial support was provided by Chulalongkorn University. Warinthorn Chavasiri reports a relationship with Chulalongkorn University that includes: employment., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objectives: We investigated potential relationships among initial lesions of the intestinal mucosa, fecal enzymatic activities and microbiota profiles., Methods: Fecal samples from 54 volunteers were collected after recruitment among individuals participating in a colorectal cancer (CRC) screening program in our region (Northern Spain) or attending for consultation due to clinical symptoms; intestinal mucosa samples were resected during colonoscopy. Enzymatic activities were determined in fecal supernatants by a semi-quantitative method. The fecal microbiota composition was determined by 16S rRNA gene-based sequencing. The results were compared between samples from clinical diagnosis groups (controls and polyps), according with the type of polyp (hyperplastic polyps or conventional adenomas) and considering the grade of dysplasia for conventional adenomas (low and high grade dysplasia)., Results: High levels of α-glucosidase activity were more frequent among samples from individuals diagnosed with intestinal polyps, reaching statistical significance for conventional adenomas and for low grade dysplasia adenomas when compared to controls. Regarding the microbiota profiles, higher abundance of Christensenellaceae_R-7 group and Oscillospiraceae_UCG-002 were found in fecal samples displaying low α-glucosidase activity as compared with those with higher activity as well as in controls with respect to conventional adenomas. A relationship was evidenced among intestinal mucosal lesions, gut glucosidase activities and intestinal microbiota profiles., Conclusions: Our findings suggest a relationship among altered fecal α-glucosidase levels, the presence of intestinal mucosal lesions, which can be precursors of CRC, and shifts in defined microbial groups of the fecal microbiota., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 csic. Published by Elsevier Ltd.. All rights reserved.)

α-Glycosidase inhibition is one of the main approaches to treat Diabetes mellitus. Polyphenolic moieties are known to be responsible for yielding exhibit potent α-glycosidase inhibitory effects. In addition, compounds containing benzothiazole and Schiff base functionalities were previously reported to show α-glycosidase inhibition. In this paper, the synthesis of seven new phloroglucinol-containing benzothiazole Schiff base derivatives through the reaction of 6-substituted-2-aminobenzothiazole compounds with 2,4,6-trihydroxybenzaldehyde using acetic acid as a catalyst was reported. The synthesized compounds were characterized using spectroscopic methods such as FT-IR, 1 H NMR, 13 C NMR, and elemental analysis. The synthesized compounds were evaluated for their inhibitory effects on α-glycosidase, compounds 3f and 3g were found to show significant inhibitory properties when compared to the positive control. The IC 50 values of 3f and 3g were calculated as 24.05 ± 2.28 and 18.51 ± 1.19 µM, respectively. Kinetic studies revealed that compounds 3f and 3g exhibited uncompetitive mode of inhibition against α-glycosidase. Molecular modeling predicted druglikeness for the title compounds and underpinned the importance of phloroglucinol hydroxyls for interacting with the key residues of α-glycosidase., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Progesterone has been shown to stimulate glycogen catabolism in uterine epithelial cells. Acid α-glucosidase (GAA) is an enzyme that breaks down glycogen within lysosomes. We hypothesized that progesterone may stimulate glycogenolysis in the uterine epithelium via GAA. We found that GAA was more highly expressed in the stroma on Day 1 than on Day 11. However, GAA did not appear to differ in the epithelium on Days 1 and 11. Progesterone (0-10 μM) had no effect on the levels of the full-length inactive protein (110 kDa) or the cleaved (active) peptides present inside the lysosome (70 and 76 kDa) in immortalized bovine uterine epithelial (BUTE) cells. Furthermore, the activity of GAA did not differ between the BUTE cells treated with 10 μM progesterone or control. Overall, we confirmed that GAA is present in the cow endometrium and BUTE cells. However, progesterone did not affect protein levels or enzyme activity., (© 2024 The Author(s). Reproduction in Domestic Animals published by Wiley‐VCH GmbH.)

Type 2 diabetes mellitus (T2DM) has become a serious public health problem both in our country and worldwide, being the most prevalent type of diabetes. The combined use of drugs in the treatment of T2DM leads to serious side effects, including gastrointestinal problems, liver toxicity, hypoglycemia, and treatment costs. Hence, there has been a growing emphasis on drugs that demonstrate dual interactions. Several studies have suggested that dual-target agents for peroxisome proliferator-activated receptor-γ (PPAR-γ) and alpha-glucosidase (α-glucosidase) could be a potent approach for treating patients with diabetes. We aim to develop new antidiabetic agents that target PPAR-γ and α-glucosidase enzymes using molecular modeling techniques. These compounds show dual interactions, are more effective, and have fewer side effects. The molecular docking method was employed to investigate the enzyme-ligand interaction mechanisms of 159 newly designed compounds with target enzymes. Additionally, we evaluated the ADME properties and pharmacokinetic suitability of these compounds based on Lipinski and Veber's rules. Compound 70, which exhibited favorable ADME properties, demonstrated more effective binding energy with both PPAR-γ and α-glucosidase enzymes (-12,16 kcal/mol, -10.07 kcal/mol) compared to the reference compounds of Acetohexamide (-9.31 kcal/mol, -7.48 kcal/mol) and Glibenclamide (-11.12 kcal/mol, -8.66 kcal/mol). Further, analyses of MM/PBSA binding free energy and molecular dynamics (MD) simulations were conducted for target enzymes with compound 70, which exhibited the most favorable binding affinities with both enzymes. Based on this information, our study aims to contribute to the development of new dual-target antidiabetic agents with improved efficacy, reduced side effects, and enhanced reliability for diabetes treatment., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

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., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)