Alpha-glucosidase Assay Research Articles

Eco-Friendly synthesis of manganese nanoparticles from Syzygium aromaticum and study of their biological activities

Different metallic nanoparticles are being explored, but manganese nanoparticles (MnNPs) have not yet been studied extensively. In this study, MnNPs were synthesized by a plant-based (clove extract) method, and the synthesized MnNPs were physically characterized using different techniques. SEM analysis showed a size range of MnNPs between 100 nm and 500 nm with spherical shapes. XRD analysis showed the crystalline nature of MnNPs. The PDI of 0.872 and the zeta potential at 10 mV indicate that the MnNPs are aggregated and polydispersed. MnNPs showed a maximum zone of inhibition against Staphylococcus aureus, i.e. 30 mm. The DPPH assay confirmed the radical scavenging ability of nanoparticles with an IC50 of 51.18 µg/ml. The alpha-amylase and alpha-glucosidase assays indicated that green synthesized MnNPs can act as an anti-diabetic agent with 26.65 µg/ml and 27.37 µg/ml IC50 values, respectively. In conclusion, this work exhibited a cost-effective and non-toxic method of MnNPs synthesis with potential biomedical applications.

Anti-obesity potential of bioactive guided fractions of Annona squamosa linn. leaves extract: a combination of in-vitro, in-vivo and in-silico studies along with profiling of lead compounds by HPTLC MS-MSn method.

The antiobesity potential of bioactive fractions derived from Annona squamosa was approached using a combination of in vitro, in silico and in-vivo studies. The study was analyzed to validate and select the potent bioactive fractions of A. squamosa leaves extract through in vitro and in vivo activities targeting obesity. The phytochemical properties of the bioactive fractions were investigated utilizing total flavonoid, total phenolic and total steroidal content. Further, in vitro antioxidant assays such as nitric oxide (NO2), DPPH, ABTS, and Hydrogen peroxide (H2O2) scavenging assays were performed whereas pancreatic lipase, Alpha-amylase and Alpha glucosidase assays were carried out for enzyme inhibition activities. The overall study revealed that fractions F2 and F3 had shown significant in vitro activities targeting obesity. The selected potent fractions (F2 and F3) were orally bio-screened for efficacy in MSG-HFD-induced obese mice at 80mg/kg/bw. The invivo study confirmed that fractions 2 and 3 with a dose of 80mg/kg/bw had a significant potency compared to obese control and standard for various parameters. Body weight and lipid metrics were significantly reduced, and histological examinations revealed considerable beneficial alterations in the organs of the animals. Further HPTLC MS-MSn was used to characterize and identify the major compounds in the potent bioactive fractions, which confirmed the presence of seven major compounds: Ascorbic acid, Gallic acid, Quercetin, β-sitosterol, Stigmasterol, Caffeine and Epigallocatechin gallate. An in silico model was then employed to determine the best binding activity of the identified compound towards the specific receptors targeting obesity, confirming the most effective docking score towards stigmasterol and sitosterol. The in vitro and in vivo studies of derived bioactive fractions of A. squamosa leaves extract revealed a possible therapeutic approach towards anti-obesity activity for the first time.

In vitro Antioxidant, Antidiabetic and Antibacterial Activities of Orthosiphon diffusus

This study aims to analyze the antioxidant, antidiabetic, and antibacterial properties of the leaves of the plant Orthosiphon diffusus, which were investigated in vitro. Leaves of the plant were dried and converted into powdered form. The presence of phytochemicals in the leaves of Orthosiphon diffusus were analysed for solvents like water, ethanol, acetone and petroleum ether. The antioxidant activity of the leaves of Orthosiphon diffusus was identified using assays for scavenging the 1,1-diphenyl-2-picrylhydrazyl hydrate, ferric reducing antioxidants, nitric oxide and hydrogen peroxide radicals. The antidiabetic property was estimated with alpha-amylase and alpha-glucosidase assays. Leaf extract was tested against three bacterial species namely Bacillus subtilis, Escherichia coli and Staphylococcus aureus by well diffusion method. Maximum number of phytochemicals were present in water extract which was then used for further studies. Highest scavenging activity was found to be 76%, 89%, 88% and 81% at 50µg/ml for all the antioxidant assays. Highest inhibition of 90.26% and 90.5% was observed at 50µg/ml for alpha amylase and alpha glucosidase assays respectively. Highest zone of inhibition of 1.4cm was observed in S.aureus at 100µg/ml concentration. Leaves of Orthosiphon diffusus has excellent antioxidant and antidiabetic properties and it was really effective against bacteria.

<i>In-Vitro</i> and <i>In-Silico</i> Alpha Amylase and Alpha Glucosidase Inhibitory Activity of Baicaelin

Diabetes mellitus is a metabolic disorder characterized by high blood glucose level in the body. It occurs due to the inadequate amount of insulin secreted in the body or resistance of insulin receptors. In the present study, Baicalein a flavone glycoside was evaluated for its effect on alpha-amylase and alpha-glucosidase enzymes using in-vitro assays by extracting respective enzymes from whole wheat and barley in combination with in-silico analysis. In-vitro alpha amylase inhibitory activity and in-vitro alpha glucosidase inhibitory activity was performed using acarbose as a standard drug. The molecular docking study was performed using Schrodinger (Maestro V 11.5) software. The parameters glide score, Lipinski rule for drug likeliness, bioactive scoring and ADME properties were assessed in the docking study. Further, the antioxidant activity of baicalein was performed using DPPH assay, Nitric oxide scavenging activity. The cytotoxicity of baicalein was evaluated using the Brine shrimp lethality assay. The alpha-amylase assay performed showed IC<sub>50</sub> value of 48.40 ?g/ml for baicalein whereas alpha-glucosidase assay showed an IC<sub>50</sub> value of 16.03 ?g/ml. Baicalein shows the glide score of-5.565 with 5EOF and glide score of -5.339 with 5NN8 in the molecular docking study. The highest percentage of DPPH radical scavenging activity and nitrous oxide scavenging activity were found to be 27% at 160 ?g/ml and 50.02% at 160 ?g/ml respectively. Based on further in vivo and clinical trials, baicalein may be used for the management of hyperglycaemia.

Synthesis, In-vitro Antioxidant, Anti-diabetic Evaluation and Docking Studies of Newly Synthesized Benzoxazole Derivatives

In the present study, a set of different benzoxazole derivatives has been synthesized from ethyl acetoacetate, ethoxymethylene malononitrile, NaNO2, and organic acids. Analytical instruments like proton NMR (1H), carbon NMR (13C), infrared spectroscopy (IR), and LC-MS mass spectrometry were used for structural characterization. Synthesized molecules were evaluated for In-vitro antioxidant property (DPPH assay, Total antioxidant & reducing power method) and anti-diabetic property (alpha-amylase & alpha-glucosidase assay). In silico, studies against Human pancreatic alpha-amylase (PDB ID: 3BAW) have been carried out to get the binding approach of the ligand towards the protein. The results demonstrated that compounds namely 5b, 6b, 3b and 4b had potent antioxidant and anti-diabetic activity compared with ascorbic acid and acarbose. HIGHLIGHTS Anti-oxidant (DPPH assay, Total antioxidant and Reducing power) and Anti-diabetic (alpha-amylase & alpha-glucosidase assay) activities performed for synthesized molecules Sulfonamide substitutions are more potent towards biological activities In silico docking studies correlate with in vitro studies The small three-dimensional, stable structure and its ability to form hydrogen bonding the molecules show good activity towards antioxidant and anti-diabetic GRAPHICAL ABSTRACT

In-Vitro and In-Silico Alpha Glucucosidase Inhibitory activity of Oroxylum indicum

Background: Diabetes mellitus is a metabolic condition characterized by elevated blood glucose levels in the bloodstream. It occurs due to the inadequate amount of insulin secreted in the body or resistance of insulin receptors. Objective: In the present study, for its effect on alpha-amylase and alpha-glucosidase enzymes, Oroxylum indicuma flavone glycoside was assessed using in-vitro assays by removing the respective enzymes from whole wheat and barley in conjunction with in-silico analysis. Method: in-vitro alpha amylase inhibitory activity and in-vitro alpha glucosidase inhibitory activity was performed using acarbose as a standard drug. The molecular docking study was performed using Schrodinger (Maestro V 11.5) software. The parameters glide score, Lipinski rule for drug likeliness, bioactive scoring and ADME properties were assessed in the docking study. In addition, baicalein's antioxidant function was assessed using DPPH assay, nitric oxide scavenging activity. The cytotoxicity of Oroxylum indicumwas evaluated using the Brine shrimp lethality assay. Results: The alpha-amylase assay performed showed IC50 value of 48.40 µg/ml for Oroxylum indicumwhereas alpha-glucosidase assay showed an IC50 value of 16.03 µg/ml. Oroxylum indicumshows the glide score of-5.565 with 5EOF and glide score of -5.339 with 5NN8 in the molecular docking study. The highest percentage of DPPH radical scavenging activity and nitrous oxide scavenging activity were found to be.27% at160 µg/ml and 50.02% at the concentrations of 160 µg/ml respectively. Conclusion: Based on further in vivo and clinical trials, Oroxylum indicummay be used for the management of hyperglycaemia.

Comparative Analysis Of In Vitro Antidiabetic Activity Of Wild And Micropropagated Solanum Trilobatum L

Diabetes is metabolic disorder which is characterized by an increase in glucose level due to a relative deficiency of insulin. Recent decades have experienced a very high prevalence of diabetes mellitus. One way of treating diabetes is to reduce gastrointestinal glucose production by inhibiting carbohydrate digesting enzymes called pancreatic alpha-amylase and intestinal alpha-glucosidase. The present study aims to compare the efficacy of wild and micropropagated Solanum trilobatum for its in vitro antidiabetic property. Solanum trilobatum grown in vitro under aseptic conditions was compared with wild-grown, and the results have revealed that both wild and micropropagated plants have effective dose-dependent inhibition of alpha-amylase and alpha-glucosidase enzyme. For both alpha-amylase and alpha-glucosidase assay micropropagated plant has shown lesser efficacy at all concentrations when compared to that of wild grown. still micropropagated showed effective inhibition with nearly 90% similarity.

Onion Peel: Turning a Food Waste into a Resource.

Food waste is a serious problem for food processing industries, especially when it represents a loss of a valuable source of nutrients and phytochemicals. Increasing consumer demand for processed food poses the problem of minimizing waste by conversion into useful products. In this regard, onion (Allium cepa) waste consisting mainly of onion skin is rich in bioactive phenolic compounds. Here, we characterized the flavonoid profiles and biological activities of onion skin wastes of two traditional varieties with protected geographical indication (PGI), the red “Rossa di Tropea” and the coppery “Ramata di Montoro”, typically cultivated in a niche area in southern Italy. The phytochemical profiles of exhaustive extracts, characterized by ultra-high-performance liquid chromatography coupled with ultraviolet (UV) detection and high-resolution mass spectrometry, revealed that flavonols and anthocyanins were the characteristic metabolite classes of onion skins. Quercetin, quercetin glucosides and their dimer and trimer derivatives, and, among anthocyanins, cyanidin 3-glucoside, were the most abundant bioactive compounds. The potential of onion skins was evaluated by testing several biological activities: ABTS/oxygen radical absorbance capacity (ORAC) and in vitro alpha-glucosidase assays were performed to evaluate the antioxidant and anti-diabetic properties of the extracts and of their main compounds, respectively, and proliferative activity was evaluated by MTT assay on human fibroblasts. In the present study, by observing various biological properties of “Rossa di Tropea” and “Ramata di Montoro” onion-dried skins, we clearly indicated that this agricultural waste can provide bioactive molecules for multiple applications, from industrial to nutraceutical and cosmetical sectors.

Comparative Study on the Antidiabetic Efficacy of Unripe and Ripe Fruit Extracts of Siraitia grosvenorii and the Possible Mechanism of Action

Aims: The ripe fruit of Siraitia grosvenorii (Swingle) C. Jeffrey (Cucurbitaceae) is used in Traditional Chinese Medicine (TCM) for treatment of diabetes. The ripe fruit is very edible, nutritious and of high sweet taste, while the unripe fruit which is usually very bitter and not edible, has not been widely studied. Therefore, the aim of this study is to evaluate the antidiabetic activity of the unripe fruit of S. grosvenorii and to compare it with that of the ripe fruit as well as to determine their possible mechanism of action.
 Methodology: The method of streptozotocin-nicotinamide induced diabetic animal model in mice was employed and mice with blood glucose greater than 9.0 mmol/l were selected for treatment with unripe fruit extract (UFE) and ripe fruit extract (RFE) for 24 days. Alpha-glucosidase and alpha amylase enzymes inhibitory assays for determination of possible mechanism of action, were performed.
 Results: The RFE exhibited better efficacy in antidiabetic activity than the UFE, though the later displayed better potency in activity. The RFE, UFE (300 mg/kg) and glibenclamide exhibited significant (P<0.05) percentage blood glucose reduction (PBGR) of 67.04, 60.69 and 62.88%, respectively, in diabetic mice. Alpha glucosidase assay showed median inhibitory concentration (IC50) value of 7.60 and 6.62 mg/ml for RFE and UFE, respectively, while the alpha amylase inhibitory assay exhibited percentage inhibition of 84.78 and 95.10% for RFE and UFE (25 mg/ml), respectively.
 Conclusion: The ripe and unripe extracts of S. grosvenorii exhibited antidiabetic activities, and RFE proved a better efficacious activity than UFE, which showed more potent activity. In addition, the antidiabetic activity is likely being mediated through alpha glucosidase and alpha amylase enzymes inhibition.

Sensitivity of whole exome sequencing in detecting infantile- and late-onset Pompe disease.

Pompe disease is a metabolic myopathy with a wide spectrum of clinical presentation. The gold-standard diagnostic test is acid alpha-glucosidase assay on skin fibroblasts, muscle or blood. Identification of two GAA pathogenic variants in-trans is confirmatory. Optimal effectiveness of enzyme replacement therapy hinges on early diagnosis, which is challenging in late-onset form of the disease due to non-specific presentation. Next-generation sequencing-based panels effectively facilitate diagnosis, but the sensitivity of whole-exome sequencing (WES) in detecting pathogenic GAA variants remains unknown. We analyzed WES data from 93 patients with confirmed Pompe disease and GAA genotypes based on PCR/Sanger sequencing. After ensuring that the common intronic variant c.-32-13T>G is not filtered out, whole-exome sequencing identified both GAA pathogenic variants in 77/93 (83%) patients. However, one variant was missed in 14/93 (15%), and both variants were missed in 2/93 (2%). One complex indel leading to a severe phenotype was incorrectly called a nonsynonymous substitution c.-32-13T>C due to misalignment. These results demonstrate that WES may fail to diagnose Pompe disease. Clinicians need to be aware of limitations of WES, and consider tests specific to Pompe disease when WES does not provide a diagnosis in patients with proximal myopathy, progressive respiratory failure or other subtle symptoms.

Two cases of Pompe's disease: case report and review of literature

Glycogen storage disease type II (also called Pompe's disease or acid maltase deficiency) is an autosomal recessive metabolic disorder which causes an accumulation of glycogen in the lysosomes due to deficiency of the lysosomal acid alpha-glucosidase enzyme. It is the only glycogen storage disease with a defect in lysosomal metabolism, and the first glycogen storage disease to be identified in 1932. The build-up of glycogen causes progressive muscle weakness (myopathy) throughout the body and affects various body tissues, particularly in the heart, skeletal muscles, liver, and nervous system.We are presenting two cases of infantile form of Pompe's disease with secondary hypertrophic cardiomyopathy (CMP). The first case was a 1-year-old female child who presented with Ross Class III heart failure (HF) of 3 months duration. Echocardiography (ECHO) showed concentric left ventricular (LV) hypertrophy, with the posterobasal segment more hypertrophic than the inter-ventricular septum and moderate pericardial effusion. The second case was a 2-month-old male child who presented with Ross Class II HF. His ECHO showed eccentric hypertrophy of the posterobasal left ventricle, with thickening of the mitral valve leaflets and the chordae with Grade I mitral regurgitation (MR). Both children were diagnosed to have Pompe's disease by blood alpha-glucosidase assay.

Digestive proteases and carbohydrases along the alimentary tract of the stargazer, Uranoscopus scaber Linnaeus, 1753

Digestive enzyme activity and capacity (activity x tissue weight) for protein (total protease assay, 25° C) and carbohydrates (total carbohydrase and alpha-glucosidase assay at 5, 18 and 25° C) was investigated for the carnivorous stargazer, Uranoscopus scaber along its digestive tract. Results indicated that whole gut total protease activity was highest at pH 1.5 (P<0.05) (25° C) in U. scaber, (6.64±2.55 mg tyrosine per g digestive tract per minute, pH 1.5). Total protease activity was apparent mainly in the stomach at pH 1.5 (9.73±3.3), and to a lesser degree in the anterior intestine (11.15±1.5, pH 10.0) and pyloric caeca (4.92±2.06, pH 10.0), especially at pH 9.0 and 10.0. Furthermore, 60% of total capacity for protein digestion derives from the stomach region, which takes up 65% of the digestive tract. Total carbohydrase activity and capacity levels were very low compared to other carnivorous teleosts, indicating very low tendency for complex, large molecular weight carbohydrate digestion. However, alpha-glucosidase levels were higher, a fact which combined with relevant data for other marine carnivorous teleosts suggests a possible role of disaccharide in relation to marine carnivorous fish dietary carbohydrate inclusion.

Improvement in the assessment of human epididymal function by the use of inhibitors in the assay of α‐glucosidase in seminal plasma

Seminal alpha-glucosidase has been used clinically as a marker of epididymal function. In this study enzyme inhibitors were used to increase the specificity of the human seminal alpha-glucosidase assay and improve its diagnostic value as an indicator of distal epididymal occlusion in cases of azoospermia. Sodium dodecylsulphate was added to the sample to eliminate the interfering acid isoenzyme secreted by the prostate gland, and castanospermine was used with semen pools to provide a semen blank for the assay by eliminating non-glucosidase-regulated degradation of the substrate. With both inhibitors included in the assay, glucosidase activity in semen samples from 17 fathers was measured to provide reference values for the clinic (lower threshold 18 mU per ejaculate). With the improved assay glucosidase was non-detectable in 8 out of 11 cases of proven and 5 out of 8 cases of suspected ductal obstruction; other azoospermic patients with distal occlusion had values below 11 mU per ejaculate.

Selective determination of the activities of neutral and acid alpha-glucosidase using discontinuous assays.

Most biological fluids contain both neutral and acid alpha-glucosidase. Optimal conditions were therefore developed for the selective determination of the activity of neutral and acid alpha-glucosidase, using 2-step, discontinuous assays. In the first step of the assay of neutral alpha-glucosidase, glucose was liberated from maltose (citrate-phosphate buffer, pH 6.8, 20 mmol/l maltose, 25 mmol/l turanose). Under these incubation conditions, turanose inhibited the residual activity of acid alpha-glucosidase almost completely without influencing the activity of neutral alpha-glucosidase. In the first step of the acid alpha-glucosidase assay, glucose was liberated from maltose (citrate-phosphate buffer, pH 3.8, 50 mmol/l maltose, 2 mol/l potassium chloride). Under these incubation conditions, potassium ions stimulate the activity of acid alpha-glucosidase and simultaneously inhibit almost completely the residual activity of neutral alpha-glucosidase. In the second step of the assay of neutral and acid alpha-glucosidase, the liberated glucose was measured by hexokinase/glucose-6-phosphate dehydrogenase. The effect of turanose and potassium ions on neutral and acid alpha-glucosidase from human urine was characterized.

A fluorometric assay of alpha-glucosidase and its application in the study of Pompe's disease.

A fluorometric assay of alpha-glucosidase and its application in the study of Pompe's disease.

A suction-controlled nasal aspirator for collection of nasopharyngeal secretions

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