Mixed inhibition

Introduction: Many proteins can be converted into amyloid in the laboratory. These fields are of interest from various points of view, including as a substrate for enzyme stabilization. In this research, cellulase enzyme was immobilized on amyloid nano-biofibrils obtained from bovine serum albumin and its kinetic properties were compared with the free form. Methods: The production of amyloid fibers was optimized by Congored absorbance and ThT fluorescence assay methods and was confirmed by transmission electron microscopy. Cellulase enzyme was immobilized via glutaraldehyde cross-linking bridges on amyloid nano-biofibrils. Results: The results of Congored absorbance and ThT fluorescence emission showed that the maximum amyloid fibers at 4 mg/ml of protein concentration, 60 ºC and a pH 3. Electron microscopy images confirmed the presence of amyloid fibers. Immobilizing the enzyme decreased the activity, specific activity and Vm and increased the Km of the enzyme. The optimum temperature of the enzyme increased from 40 to 50 ºC. Discussion: Amyloid nano-biofibrils can be used as a new nano-biomaterial for cellulase immobilization which introduce a useful product in cellulase-related industries.

The study was aimed to evaluate the α-glucosidase inhibitory properties of combined ethanol seed extract of Piper guineense and Tetracarpidium conophorum (CEPGTC). In vitro inhibitory assay was conducted in accordance with standard methods. p-nitrophenyl--D-glucopyranoside (pNPG) was used as a substrate. Fixed amount of the enzyme was incubated with increasing concentrations of CEPGTC seed extract (20-100 μg/ml) at 37°C for 15 min. The continuous production of p-nitrophenol was determined by measuring the absorbances at 410 nm. Acarbose at varying concentration (20-100g/ml) was used as the positive control. The median Inhibitory Concentration (IC50) values were graphically determined as the half-maximal inhibitory from plots of percent inhibition against log inhibitor concentration and by non-linear regression analysis. The enzyme kinetics (pattern of Inhibition) was determined using the Michaelis Menten's equation and Lineweaver-Burk plot. The result showed that there was inhibition in all concentrations evaluated. The IC 50 values estimated were 2.9 μg/ml and 2.5 μg/ml for CEPGTC and acarbose respectively. However, The IC 50 value for acarbose was significantly (p<0.05) different from CEPGTC which is an indication of acarbose as effective -glucosidase inhibitor thus, used as positive control. An enzyme kinetics studies from the Lineweaver-Burke plot showed that CEPGTC seed extract demonstrated an uncompetitive inhibition on α-glucosidase while acarbose exhibited non competive (mixed inhibition). The inhibitory response and mechanism of inhibition observed in this study showed that combined ethanol seed extract of Piper guineense and Tetracarpidium conophorum has the potential to reduce glucose turnover and improve Hyperglycemia.

Current antiobesity and antidiabetic tools have been insufficient to curb these diseases and frequently cause side effects; therefore, new pancreatic lipase and -glucosidase inhibitors could be excellent aids for the prevention and treatment of these diseases. The aim of this study was to identify, quantify, and characterize the chemical compounds with the highest degree of inhibitory activity of these enzymes, contained in a hydroalcoholic extract. Chemical purification was performed by liquid-liquid separation and column chromatography. Inhibitory activities were measured , employing acarbose, orlistat, and a hydroalcoholic extract as references. For structural elucidation, Nuclear Magnetic Resonance was carried out, and High Performance Liquid Chromatography was used to quantify the compounds. For -glucosidases, hydroalcoholic extract and its ethyl acetate fraction showed half-maximal Inhibitory Concentration (IC) values of 700 and 250 g/mL, for lipase, 480 and 718 g/mL, while sh...

Fabry disease is a rare genetic disorder that can affect various parts of the body, including the kidneys, heart, and skin. In this study, we aim to explore the bioinformatics impact of the compounds darifenacin, amiloride, and acitretin on inhibition of the enzyme alphagalactosidase-an enzyme relevant to Fabry disease treatment. Our investigation involves examining the binding modes of these compounds to the enzyme's active site, optimizing their binding energies, conducting docking studies, and final analyses using online tools such as H-Dock and software packages such as HyperChem, Chimera, Discovery, and PDBsum Generate. The studied compound exhibits the ability to occupy the enzyme's active site, with binding energy levels of-164.91 kcal/mol for darifenacin,-101.56 kcal/mol for amiloride, and-145.28 kcal/mol for acitretin. Considering the efficacy of these Molecules in our bioinformatics study, further investigations could analyze their effects under in vitro and in vivo conditions.

A set of structurally related O-methylated flavonoid natural products isolated from Senecio roseiflorus (1), Polygonum senegalense (2 and 3), Bhaphia macrocalyx (4), Gardenia ternifolia (5), and Psiadia punctulata (6) plant species were characterized for their interaction with human monoamine oxidases (MAO-A and-B) in vitro. Compounds 1, 2, and 5 showed selective inhibition of MAO-A, while 4 and 6 showed selective inhibition of MAO-B. Compound 3 showed~2-fold selectivity towards inhibition of MAO-A. Binding of compounds 1-3 and 5 with MAO-A, and compounds 3 and 6 with MAO-B was reversible and not time-independent. The analysis of enzyme-inhibition kinetics suggested a reversible-competitive mechanism for inhibition of MAO-A by 1 and 3, while a partially-reversible mixed-type inhibition by 5. Similarly, enzyme inhibition-kinetics analysis with compounds 3, 4, and 6, suggested a competitive reversible inhibition of MAO-B. The molecular docking study suggested that 1 selectively interacts with the active-site of human MAO-A near N5 of FAD. The calculated binding free energies of the O-methylated flavonoids (1 and 4-6) and chalcones (2 and 3) to MAO-A matched closely with the trend in the experimental IC 50 s. Analysis of the binding free-energies suggested better interaction of 4 and 6 with MAO-B than with MAO-A. The natural O-methylated flavonoid (1) with highly potent inhibition (IC 50 33 nM; Ki 37.9 nM) and >292 fold selectivity against human MAO-A (vs. MAO-B) provides a new drug lead for the treatment of neurological disorders.

A set of structurally related O-methylated flavonoid natural products isolated from Senecio roseiflorus (1), Polygonum senegalense (2 and 3), Bhaphia macrocalyx (4), Gardenia ternifolia (5), and Psiadia punctulata (6) plant species were characterized for their interaction with human monoamine oxidases (MAO-A and -B) in vitro. Compounds 1, 2, and 5 showed selective inhibition of MAO-A, while 4 and 6 showed selective inhibition of MAO-B. Compound 3 showed ~2-fold selectivity towards inhibition of MAO-A. Binding of compounds 1–3 and 5 with MAO-A, and compounds 3 and 6 with MAO-B was reversible and not time-independent. The analysis of enzyme-inhibition kinetics suggested a reversible-competitive mechanism for inhibition of MAO-A by 1 and 3, while a partially-reversible mixed-type inhibition by 5. Similarly, enzyme inhibition-kinetics analysis with compounds 3, 4, and 6, suggested a competitive reversible inhibition of MAO-B. The molecular docking study suggested that 1 selectively inte...

1 تسيز هورگ ،يرتكد يوجشناد تاقيقحت و مولع دحاو ،يملاسا دازآ هاگشناد ،يهايگ يسانش 2 داتسا تسيز هورگ ،راي د ،مولع هدكشناد ،يسانش يتشهب ديهش هاگشنا 3 شناد وراد هدكشناد ،ييوراد يميش هورگ ،راي نارهت يكشزپ مولع هاگشناد ،يزاس 4 تسيز هورگ ،داتسا تاقيقحت و مولع دحاو ،يملاسا دازآ هاگشناد ،يهايگ يسانش * هبتاكم سردآ : تسيز هورگ ،تاقيقحت و مولع دحاو ،يملاسا دازآ هاگشناد ،نارهت يهايگ يسانش نفلت : 4 – 44817170 ) 021 ( ، ربامن : 44817175 ) 021 ( كينورتكلا تسپ : moho_plant@yahoo.com

Background and Aim: Adverse drug reactions (ADR) impose costs on the health ca re system and affect public health. Identification, assessmen t and prevention of adverse drug reactions are effective factors which can influence soci al health indices. Material and Methods: In this cross-sectional study, 133 outpatient and inpatient re ports of adverse drug reactions were investigated in Kurdistan Pr ovince hospitals between 2013 and 2014. The data included demographic characteristics, type, form, rou te of administration, type of drug side effects and final outcome. Data were analyzed by chi-square multi response test. P&lt;0.05 was considered significant. Results: Our results showed that the most common complications were d matologic and respiratory reactions due to injectable forms of the drugs and antibiotics were the most common drugs which caused adverse drug reactions. The frequ ency of adverse drug reactions was higher in the women and these reactions were more c ommon between ...

Targeting tyrosinase for melanogenesis disorders is an established strategy. Hydroxyl-substituted benzoic and cinnamic acid scaffolds were incorporated into new chemotypes that displayed in vitro inhibitory effects against mushroom and human tyrosinase for the purpose of identifying anti-melanogenic ingredients. The most active compound 2-((4-methoxyphenethyl)amino)-2-oxoethyl (E)-3-(2,4-dihydroxyphenyl) acrylate (Ph9), inhibited mushroom tyrosinase with an IC50 of 0.059 nM, while 2-((4-methoxyphenethyl)amino)-2-oxoethyl cinnamate (Ph6) had an IC50 of 2.1 nM compared to the positive control, kojic acid IC50 16700 nM. Results of human tyrosinase inhibitory activity in A375 human melanoma cells showed that compound (Ph9) and Ph6 exhibited 94.6% and 92.2% inhibitory activity respectively while the positive control kojic acid showed 72.9% inhibition. Enzyme kinetics reflected a mixed type of inhibition for inhibitor Ph9 (Ki 0.093 nM) and non-competitive inhibition for Ph6 (Ki 2.3 nM) re...

Alpha-amylase (α-amylase) is a key player in the management of diabetes and its related complications. This study was intended to have an insight into the binding of caffeic acid and coumaric acid with α-amylase and analyze the effect of these compounds on the formation of advanced glycation end-products (AGEs). Fluorescence quenching studies suggested that both the compounds showed an appreciable binding affinity towards α-amylase. The evaluation of thermodynamic parameters (ΔH and ΔS) suggested that the α-amylase-caffeic/coumaric acid complex formation is driven by van der Waals force and hydrogen bonding, and thus complexation process is seemingly specific. Moreover, glycation and oxidation studies were also performed to explore the multitarget to manage diabetes complications. Caffeic and coumaric acid both inhibited fructosamine content and AGE fluorescence, suggesting their role in the inhibition of early and advanced glycation end-products (AGEs). However, the glycation inhib...

Human serum albumin (HSA) is the most abundant protein in plasma synthesized by the liver and the main modulator of fluid distribution between body compartments. It has an amazing capacity to bind with multiple ligands, offering a store and transporter for various endogenous and exogenous compounds. Huperzine A (HpzA) is a natural sesquiterpene alkaloid found in Huperzia serrata and used in various neurological conditions, including Alzheimer’s disease (AD). This study elucidated the binding of HpzA with HSA using advanced computational approaches such as molecular docking and molecular dynamic (MD) simulation followed by fluorescence-based binding assays. The molecular docking result showed plausible interaction between HpzA and HSA. The MD simulation and principal component analysis (PCA) results supported the stable interactions of the protein–ligand complex. The fluorescence assay further validated the in silico study, revealing significant binding affinity between HpzA and HSA....

Current antiobesity and antidiabetic tools have been insufficient to curb these diseases and frequently cause side effects; therefore, new pancreatic lipase and -glucosidase inhibitors could be excellent aids for the prevention and treatment of these diseases. The aim of this study was to identify, quantify, and characterize the chemical compounds with the highest degree of inhibitory activity of these enzymes, contained in a hydroalcoholic extract. Chemical purification was performed by liquid-liquid separation and column chromatography. Inhibitory activities were measured , employing acarbose, orlistat, and a hydroalcoholic extract as references. For structural elucidation, Nuclear Magnetic Resonance was carried out, and High Performance Liquid Chromatography was used to quantify the compounds. For -glucosidases, hydroalcoholic extract and its ethyl acetate fraction showed half-maximal Inhibitory Concentration (IC) values of 700 and 250 g/mL, for lipase, 480 and 718 g/mL, while sh...

Incubation of the four purified HMG-CoA reductase phosphatases with the sodium salts of eleven polycarboxylic acids at concentrations of 40 mM, inactivated the enzymes to different degrees depending on the structure of the carboxylic acids. Maleate, malonate, oxalate, citrate, and hydroxymethylglutarate produced full inactivation at the concentration tested. When the four phosphatases were incubated with these acids, a concentrationdependent inactivation was observed. Fumarate, the trans isomer of maleate, produced little inactivation of the four phosphatases. Mevalonate did not inactivate at all. A relationship between those concentrations of acid that produced a 50% inactivation and the logarithm of the stability constant of Mg2+ or Mn2+ salts of polycarboxylic acids was observed. When reductase phosphatases were incubated with mixtures of polycarboxylic sodium salts and Mg2+ or Mn2+, an increase in the molar ratio divalent cation/carboxylic acid determined an increase in the four reductase phosphatase activities. The inactivating effect of citrate was on the phosphatases (high and low forms) and not on the substrates (MHG-CoA reductase, phosphorylase, and glycogen synthase). Reactivation of the citrate-inactivated phosphatases by Mn2+ and Mg2+ depended on the phosphorylated substrates, Mn2+ being the better activat0r.l It is concluded that HMECoA reductase phosphatases are metal1oenzymes.-Hegardt, F. G., G. Gil, and V. E. Calvet. Inactivation of rat liver HMG-CoA reductase phosphatases by polycarboxylic ac

Introduction
High levels of free radicals can damage biomolecules and eventually cause oxidative stress. Bioactive peptides produced during enzymatic hydrolysis keep high health properties, such as antioxidant properties. The production of antioxidant peptides has received much attention as a new generation of natural antioxidants. Plants are one of the most abundant sources of biopolymers, especially protein. As long as the protein structure is intact, its amino acid sequence is inactive; however, during proteolysis, fermentation, and gastrointestinal digestion, these amino acids are released as oligopeptides ordinally with less than 20 amino acids and below 10 kDa in molecular weight. These peptides are more digestible and can exhibit specific bioactive properties such antioxidant properties. In this regard, the use of food waste containing protein to produce bioactive peptides and increase their value has received increasing attention. Enzymatic hydrolysis can increase their functional properties by converting proteins into peptides without affecting their nutritional value. Pomegranate seed protein is a by-product of the pomegranate seed oil industry and can be a good source of bioactive peptides with antioxidant properties. According to our knowledge, there isn’t any data about the enzymatic hydrolysis of pomegranate seed protein for antioxidant peptides production. In this study, the optimal conditions for enzymatic hydrolysis of pomegranate seed protein with trypsin using the responses surface method and the effect of hydrolysis on protein structure were investigated.
Materials and Methods
In this study, the protein was extracted from pomegranate seed, and using trypsin the optimization of enzymatic hydrolysis conditions of protein was determined by Face-Centered Central Composite design, which is one of the responses surface design methods. The effect of independent variables including temperature (30 to 45 °C), time (30 to 180 minutes), and enzyme to substrate ratio (1 to 3 w/w) on DPPH free radical scavenging activity and Fe+3 reducing power as responses, was evaluated. Validation tests were performed for confirmation of the proposed values by software and the degree of hydrolysis of the samples was determined. In the next step, the unhydrolyzed and hydrolyzed protein was evaluated for molecular weight distribution and their surface hydrophobicity was compared. Finally, scanning electron microscopy images were used to confirm the hydrolysis process.
Results and Discussion
Under optimal conditions obtained from the response surface method (temperature: 37.6 °C, time: 136.55 minutes, and enzyme to substrate ratio: 2.2%), trypsin-derived hydrolyzate, showed DPPH free radical scavenging power: 87±0.89% and Fe+3 reduction power: 0.293±0.44. Under these conditions, the degree of hydrolysis was equal to 30.1±1%. The optimum conditions of hydrolysis were validated by RSM. The increase in the surface hydrophobicity of the protein after the hydrolysis process indicated the unfolding of the pomegranate seed protein chain and the exposure of its structure during the reaction. The electrophoretic profile of denatured pomegranate seed protein showed smaller peptide bands and lower band intensity, along with losing some of the peptide fractions after hydrolysis. so the efficacy of trypsin at cleaving the protein was confirmed. Evaluation of images obtained by scanning electron microscopy showed that unhydrolyzed protein had complex structures comprised of random sheets of different sizes and shapes and the protein degraded into small fragments and looser structure with many folds after enzyme hydrolysis, resulting in smaller particles compared with untreated samples with the same SEM parameters
Conclusion
Considering the consumer’s tendency toward functional foods and present concerns about the application of synthetic additives and according to the results, the hydrolyzed pomegranate seed protein prepared by trypsin shows good antioxidant capacity. In addition, there will be a reduction in waste generated by the pomegranate processing industry. Further studies will need for the isolation and identification of the specific peptides and amino acid sequences and the evaluation of their possible incorporation in food matrices.

Countless enzymes are found in the differentiated cells of human intestinal villi. One of these enzymes is lactose enzyme, which is obtained through dairy products, especially milk. There are many people who suffer from digestive problems such as bloating, nausea and vomiting after consuming milk. To solve this problem, lactose hydrolysis by lactase enzyme is used. In this research, modeling has been done based on the relevant parameters of lactose hydrolysis, which include: pH, temperature, substrate concentration (lactose), product concentration (glucose and galactose), substrate consumption time, relative enzyme activity and stirrer speed. The simulation of the experiment was done through the famous model of Michael Menton for fixed and soluble enzyme. In order to ensure the selected model, the data obtained from this method were compared with competitive, non-competitive, mixed linear and non-competitive inhibitor kinetic models, according to the simulation, the best enzyme activity, stabilized lactase at 550C temperature in 160 hours was obtained. Also, lactase stabilized at 600C temperature after 120 hours has the greatest effect of time on enzyme inactivation at temperatures and in the soluble and stabilized state.

Current antiobesity and antidiabetic tools have been insufficient to curb these diseases and frequently cause side effects; therefore, new pancreatic lipase and -glucosidase inhibitors could be excellent aids for the prevention and treatment of these diseases. The aim of this study was to identify, quantify, and characterize the chemical compounds with the highest degree of inhibitory activity of these enzymes, contained in a hydroalcoholic extract. Chemical purification was performed by liquid-liquid separation and column chromatography. Inhibitory activities were measured , employing acarbose, orlistat, and a hydroalcoholic extract as references. For structural elucidation, Nuclear Magnetic Resonance was carried out, and High Performance Liquid Chromatography was used to quantify the compounds. For -glucosidases, hydroalcoholic extract and its ethyl acetate fraction showed half-maximal Inhibitory Concentration (IC) values of 700 and 250 g/mL, for lipase, 480 and 718 g/mL, while sh...

Hepatocellular carcinoma (HCC), or liver cancer, is the fourth largest cancer in Indonesia, with 21,392 new cases and around 20,920 deaths. One of the standard drugs for liver cancer patients is lenvatinib, but lenvatinib has dangerous side effects such as hypertension. Previous studies reported that jackfruit root extract (Artocarpus heterophyllus Lam.) contains prenylated flavonoid compounds known to have anticancer activity. This study aims to find compounds that have the potential to the anticancer liver from jackfruit root by understanding the interaction between prenylated flavonoid derivative compounds against the VEGFR2 receptor (PDB ID: 3WZE) in silico. The methods include toxicity and pharmacokinetic screening, drug scanning, docking, and molecular dynamics simulation. The toxicity, pharmacokinetic, and drug scans of cycloartocarpesin are better than lenvatinib. The docking cycloartocarpesin compound showed ∆G -8.49 kcal/mol and Ki 0.59967 M lower than lenvatinib by formin...

This study was designed to investigate the correlation between thermodynamic parameters, ideal solubility and some pharmacokinetic parameters of the compounds. Methods: For thermodynamics analysis, 5 mg of pure drug was weighed in a aluminum pan. Thermodynamic parameters were used for determination of ideal solubility. Correlation between ideal solubility and physicochemical and pharmacokinetic parameters was investigated. Results: The results indicated that there is a linear correlation between ideal solubility and permeability with R=0.8. There are also meaningful correlation between ideal solubility and other physicochemical and pharmacokinetic parameters. Conclusion: This investigation revealed that the ideal solubility could be an appropriate parameter for prediction of drugs pharmacokinetics.

Protein tyrosine phosphatase 1B (PTP1B) plays important role in diabetes, obesity and cancer. The methanol extract of the gum resin of Garcinia hanburyi (G. hanburyi) showed potent PTP1B inhibition at 10µg/ml. The active compounds were identified as prenylated caged xanthones (1-9) which inhibited PTP1B in dose-dependent manner. Carboxybutenyl group within caged motif (A ring) was found to play a critical role in enzyme inhibition such as 1-6 (IC50s=0.47-4.69µM), whereas compounds having hydroxymethylbutenyl 7 (IC50=70.25µM) and methylbutenyl 8 (IC50&gt;200µM) showed less activity. The most potent inhibitor, gambogic acid 1 (IC50=0.47µM) showed 30-fold more potency than ursolic acid (IC50=15.5µM), a positive control. In kinetic study, all isolated xanthones behaved as competitive inhibitors which were fully demonstrated with Km, Vmax and Kik/Kiv ratio. It was also proved that inhibitor 1 operated under the enzyme isomerization model having k5=0.0751µM(-)(1)S(-)(1), k6=0.0249µM(-)(1)...

Sodium salts of four n-alkyl xanthate compounds, C2H5OCS2Na (I), C3H7OCS2Na (II), C4H9OCS2Na (III), and C6H13OCS2Na (IV) were synthesized and examined for inhibition of both cresolase and catecholase activities of mushroom tyrosinase (MT) in 10 mM sodium phosphate buffer, pH 6.8, at 293 K using UV spectrophotometry. 4-[(4-Methylbenzo)azo]-1,2-benzendiol (MeBACat) and 4-[(4-methylphenyl)azo]-phenol (MePAPh) were used as synthetic substrates for the enzyme for catecholase and cresolase reactions, respectively. Lineweaver-Burk plots showed different patterns of mixed, competitive or uncompetitive inhibition for the four xanthates. For the cresolase activity, I and II showed uncompetitive inhibition but III and IV showed competitive inhibition pattern. For the catecholase activity, I and II showed mixed inhibition but III and IV showed competitive inhibition. The synthesized compounds can be classified as potent inhibitors of MT due to their Ki values of 13.8, 11, 8 and 5 microM for the...

Three iso-alkyldithiocarbonates (xanthates), as sodium salts, C 3 H 7 OCS 2 Na (I), C 4 H 9 OCS 2 Na (II) and C 5 H 11 OCS 2 Na (III), were synthesized, by the reaction between CS 2 with the corresponding iso-alcohol in the presence of NaOH, and examined for inhibition of both cresolase and catecholase activities of mushroom tyrosinase (MT) from a commercial source of Agricus bisporus. 4-[(4-methylbenzo)azo]-1,2-benzendiol (MeBACat) and 4-[(4-methylphenyl)azo]-phenol (MePAPh) were used as synthetic substrates for the enzyme for the catecholase and cresolase reactions, respectively. Lineweaver-Burk plots showed different patterns of mixed and competitive inhibition for the three xanthates and also for cresolase and catecholase activities of MT. For cresolase activity, I and II showed a mixed inhibition pattern but III showed a competitive inhibition pattern. For catecholase activity, I showed mixed inhibition but II and III showed competitive inhibition. These new synthesized compounds are potent inhibitors of MT with K i values of 9.8, 7.2 and 6.1 mM for cresolase inhibitory activity, and also 12.9, 21.8 and 42.2 mM for catecholase inhibitory activity for I, II and III, respectively. They showed a greater inhibitory potency towards the cresolase activity of MT. Both substrate and inhibitor can be bound to the enzyme with negative cooperativity between the binding sites (a. 1) and this negative cooperativity increases with increasing length of the aliphatic tail in these compounds in both cresolase and catecholase activities. The cresolase inhibition is related to the chelating of the copper ions at the active site by a negative head group (S 2) of the anion xanthate, which leads to similar values of K i for all three xanthates. Different K i values for catecholase inhibition are related to different interactions of the aliphatic chains of I, II and III with hydrophobic pockets in the active site of the enzyme.

Current antiobesity and antidiabetic tools have been insufficient to curb these diseases and frequently cause side effects; therefore, new pancreatic lipase and -glucosidase inhibitors could be excellent aids for the prevention and treatment of these diseases. The aim of this study was to identify, quantify, and characterize the chemical compounds with the highest degree of inhibitory activity of these enzymes, contained in a hydroalcoholic extract. Chemical purification was performed by liquid-liquid separation and column chromatography. Inhibitory activities were measured , employing acarbose, orlistat, and a hydroalcoholic extract as references. For structural elucidation, Nuclear Magnetic Resonance was carried out, and High Performance Liquid Chromatography was used to quantify the compounds. For -glucosidases, hydroalcoholic extract and its ethyl acetate fraction showed half-maximal Inhibitory Concentration (IC) values of 700 and 250 g/mL, for lipase, 480 and 718 g/mL, while sh...

For the first time, α-glucosidase, α-amylase, aldose reductase, and glycation at multiple stages inhibitory assays were used to explore the antidiabetic potential of whole unripe jackfruit (peel with pulp, flake, and seed). Two polyphenols (phenolic acids) with strong antihyperglycaemic activity were isolated from the methanol extract of whole jackfruit flour (MJ) using activity-guided repeated fractionation on a silica gel column chromatography. The bioactive compounds isolated were identified as 3-(3,4-Dihydroxyphenyl)-2-propenoic acid (caffeic acid: CA) and 4-Hydroxy-3,5-dimethoxybenzoic acid (syringic acid: SA) after various physicochemical and spectroscopic investigations. CA (IC50: 8.0 and 26.90 µg/mL) and SA (IC50: 7.5 and 25.25 µg/mL) were identified to inhibit α-glucosidase and α-amylase in a competitive manner with low Ki values. In vitro glycation experiments further revealed that MJ and its components inhibited each stage of protein glycation as well as the generation of...

Several organic cations, such as guanidino compounds and polyamines, have been found to accumulate in plasma of patients with kidney failure due to inadequate renal clearance. Here, we studied the interaction of cationic uremic toxins with renal organic cation transport in a conditionally immortalized human proximal tubule epithelial cell line (ciPTEC). Transporter activity was measured and validated in cell suspensions by studying uptake of the fluorescent substrate 4-(4-(dimethylamino)styryl)-N-methylpyridinium-iodide (ASP +). Subsequently, the inhibitory potencies of the cationic uremic toxins, cadaverine, putrescine, spermine and spermidine (polyamines), acrolein (polyamine breakdown product), guanidine, and methylguanidine (guanidino compounds) were determined. Concentration-dependent inhibition of ASP + uptake by TPA, cimetidine, quinidine, and metformin confirmed functional endogenous organic cation transporter 2 (OCT2) expression in ciPTEC. All uremic toxins tested inhibited ASP + uptake, of which acrolein required the lowest concentration to provoke a half-maximal inhibition (IC 50 =44±2 μM). A Dixon plot was constructed for acrolein using three independent inhibition curves with 10, 20, or 30 μM ASP + , which demonstrated competitive or mixed type of interaction (K i =93 ± 16 μM). Exposing the cells to a mixture of cationic uremic toxins resulted in a more potent and biphasic inhibitory response curve, indicating complex interactions between the toxins and ASP + uptake. In conclusion, ciPTEC proves a suitable model to study cationic xenobiotic interactions. Inhibition of cellular uptake transport was demonstrated for several The manuscript was written through contributions of all authors. All authors have given approval to the final version of the manuscript.

Octocrylene is a widely used ingredient in sunscreen products, and it has been observed that the use of sunscreen has been increasing over the last few decades. In this paper, we investigated the way in which sunscreen’s ingredient octocrylene may disrupt normal vitamin D synthesis pathway, resulting in an imbalance in vitamin D levels in the body. The key techniques used for this insilico investigation were molecular docking, molecular dynamic (MD) simulation, and MMPBSA-based assessment. Vitamin D abnormalities have become very common in human health. Unknown exposure to chemicals may be one of the important risk factors. In molecular docking analysis, octocrylene exhibited a binding energy of −11.52 kcal/mol with vitamin D binding protein (1KXP) and −11.71 for the calcitriol native ligand. Octocrylene had a binding potency of −11.152 kcal/mol with the vitamin D receptor (1DB1), and calcitriol had a binding potency of −8.73 kcal/mol. In addition, octocrylene has shown binding ener...

For the first time, α-glucosidase, α-amylase, aldose reductase, and glycation at multiple stages inhibitory assays were used to explore the antidiabetic potential of whole unripe jackfruit (peel with pulp, flake, and seed). Two polyphenols (phenolic acids) with strong antihyperglycaemic activity were isolated from the methanol extract of whole jackfruit flour (MJ) using activity-guided repeated fractionation on a silica gel column chromatography. The bioactive compounds isolated were identified as 3-(3,4-Dihydroxyphenyl)-2-propenoic acid (caffeic acid: CA) and 4-Hydroxy-3,5-dimethoxybenzoic acid (syringic acid: SA) after various physicochemical and spectroscopic investigations. CA (IC50: 8.0 and 26.90 µg/mL) and SA (IC50: 7.5 and 25.25 µg/mL) were identified to inhibit α-glucosidase and α-amylase in a competitive manner with low Ki values. In vitro glycation experiments further revealed that MJ and its components inhibited each stage of protein glycation as well as the generation of...

Rio1 kinase is an atypical protein kinase that is essential for the proper maturation of the 40S subsunit during ribosome biogenesis. Ribosome biogenesis is linked to cell cycle progression and studies have shown that the process is upregulated in both normal and abnormal highly proliferative cells in order to meet cell demands. In an effort to regulate cell proliferation especially in abnormal dividing cells, the work described here takes the approach of modulating ribosome biogenesis by targeting Rio1 kinase. Several small molecules were tested for binding to afRio1 and toyocamycin, an adenosine analog, had the highest binding affinity. A co-crystal structure of afRio1 with toyocamycin bound was determined at 2.0Å revealing occupancy of toyocamycin in the ATP binding pocket. Steady state kinetic studies revealed that inhibition occurred via both competitive and non-competitive

The action of β-secretase (BACE1) is strongly correlated with the onset of Alzheimer's disease (AD). Aminochalcone derivatives were examined for their ability to inhibit BACE1. Parent aminochalcones showed two digit micromolar IC 50 s against BACE1. Potency was enhanced 10-fold or more by introducing benzenesulfonyl derivatives to the amino group: 1 (IC 50 = 48.2 μM) versus 4a (IC 50 = 1.44 μM) and 2 (IC 50 = 17.7 μM) versus 5a (IC 50 = 0.21 μM). The activity was significantly influenced by position and number of hydroxyl groups on the chalcone Bring: 3,4-dihydroxy 5a (IC 50 = 0.21 μM) > 4-hydroxy 4a (IC 50 = 1.44 μM) > 2,4-dihydroxy 6 (IC 50 = 3.60 μM) > 2,5-dihydroxy 7 (IC 50 = 16.87 μM) > des hydroxy 4b (IC 50 = 168.7 μM). Lineweaver-Burk and Dixon plots and their secondary replots indicate that compound 5a was a mixed inhibitor with reversible and time-dependent behavior. Potent BACE1 inhibitors 4a,c,f, 5a-c showed moderate inhibition against two other enzymes implicated in AD pathogenesis, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), with IC 50 s ranging between 56.1 ~ 95.8 μM and 19.5 ~ 79.0 μM, respectively.

This study was designed to investigate the correlation between thermodynamic parameters, ideal solubility and some pharmacokinetic parameters of the compounds. Methods: For thermodynamics analysis, 5 mg of pure drug was weighed in a aluminum pan. Thermodynamic parameters were used for determination of ideal solubility. Correlation between ideal solubility and physicochemical and pharmacokinetic parameters was investigated. Results: The results indicated that there is a linear correlation between ideal solubility and permeability with R=0.8. There are also meaningful correlation between ideal solubility and other physicochemical and pharmacokinetic parameters. Conclusion: This investigation revealed that the ideal solubility could be an appropriate parameter for prediction of drugs pharmacokinetics.

In this study a two-step approach was applied in order to investigate the effect of seven factors including: concentration of ammonium sulphate, potassium dihydrogen phosphate, date pulp, pH, inoculums size, agitation speed and fermentation time on the pectinlyase production by Aspergillus niger. At first step, the effects of these variables were studied using fractional factorial design. According to obtained results three factors, pH, ammonium sulphate concentration and fermentation time were considered for further study. Second step was carried out by using central composite design (CCD) in order to find optimum conditions of pH, ammonium sulphate concentration and fermentation time. After analysis of CCD, optimum condition for maximization of pectinlyase activity determined as follow: ammonium sulphate concentration 0.35%, fermentation time, 73.93 hours and pH, 4.82. Enzyme activity at this optimum condition was 1.38 U. ml .

Introduction: The function of acetylcholinesterase accelerates the acetylcholine hydrolysis process and protects the hemostasis of this neurotransmitter in the central nervous system and the peripheral tissues. Due to the fact that in diseases, such as Alzheimer's disease, the level of acetylcholine is reduced, the administration of acetylcholinesterase inhibitor drugs (AChEID) is one of the methods for preventing the progression of this disease. The majority of the researchers attempted to investigate drugs with lower side effects, especially from herbal sources. The aim of this study was to investigate the effect of methanol extract of Mentha pulegium leaves on the enzyme activity of AChE.

Materials & Methods: In this study the AChE enzyme was partially isolated from the bovine brain using homogenization, centrifugation, ammonium sulfate precipitation, and dialysis at 4 ºC. The rate of production of thiocholine from acetylthiocholine iodide was measured according to Ellman's method. Subsequently, the methanolic extract of Mentha pulegium leaves was prepared by the maceration method. Then the inhibitory effect of the extract on the AChE was measured. Ethics code: IR.umz.rec 1397.090


Findings: The total activity and specific activity of the partially purified AChE were determined as 1143.78 U and 4.10 U/mg, respectively. The optimum pH and temperature of the acetylcholinesterase were determined to be 7.5 and 45°C respectively. Moreover, the Km and Vmax of this enzyme were estimated at 6.49 mM and 59.88 mM/min.

Discussion & Conclusions: The results of this study showed that the methanolic extract with a concentration of 26.66 mg/ml had significant effect on the activity of this enzyme. According to the results, this extract can inhibit the AchE in form of mixed inhibition. Therefore, Mentha pulegium leaf could be considered by the researchers in study and investigation of pharmaceutics.