Natural Antioxidants: An Update

Antioxidants are the body\u27s defensive mechanism against reactive oxygen species damage, which is typically caused by the different physiological activities that take place within the body. These antioxidants can be obtained from a variety of sources, including the body\u27s own endogenous antioxidants and exogenous dietary sources. Generally, food items and several types of medicinal plants are considered as the sources of natural antioxidants. Natural antioxidants possess wide variety of bioassay properties like anti-cancer, anti-aging, anti-inflammatory etc. The substitution of artificial dietary antioxidants with natural ones in recent decades has increased interest in low-cost raw materials, particularly agricultural-based products, for the discovery of new antioxidants. For both natural and synthetic antioxidants, reports of biological features such as anti-allergic, anti-mutation, anti-cancer and anti-aging activity have been reported. The most significant natural antioxidants come from regularly eating fruits and vegetables, although other plant materials and agricultural waste are also major sources of antioxidants

NMR, Novel Pharmacological and In Silico Docking Studies of Oxyacanthine and Tetrandrine: Bisbenzylisoquinoline Alkaloids Isolated from Berberis glaucocarpa Roots

Urease enzyme is responsible for gastric cancer, peptic ulcer, hepatic coma, and urinary stones in millions of people across the world. So, there is a strong need to develop new and safe antiurease drugs, particularly from natural sources. In search for new and effective drugs from natural sources bioassay-guided fractionation and isolation of Berberis glaucocarpa Stapf roots bark resulted in the isolation and characterization, on the basis of 1D and 2D NMR data, of two bisbenzylisoquinoline alkaloids, oxyacanthine (1) and tetrandrine (2), followed by urease inhibition studies. Crude extract, all the subfractions and the isolated compounds 1 and 2 displayed excellent urease enzyme inhibition properties in vitro. The antiurease nature and possible mode of action for compounds 1 and 2 were verified and explained through their molecular docking studies against jack-bean urease enzyme. Half-maximum inhibitory concentration (IC50) was calculated for compounds 1 and 2. The IC50 value was found to be 6.35 and 5.51 µg/mL for compounds 1 and 2, respectively. Both compounds 1 and 2 have minimal cytotoxicity against THP-1 monocytic cells

Equilibrium, Kinetic and Thermodynamic Studies for the Adsorption of Metanil Yellow Using Carbonized Pistachio Shell-Magnetic Nanoparticles

The cost-effective adsorbents of carbonized pistachio shell magnetic nanoparticles (CPSMNPs) were synthesized. SEM, EDX, and BET characterized the prepared CPSMNPs. The CPSMNPs were used as adsorbents to remove Metanil Yellow (MY) dye. The adsorption of MY was investigated with the effect of pH, contact time, initial dye concentration, adsorbent dose, and temperature. The SEM image of CPSMNPs reveals fine particles with an average size of 400–700 nm and a substantial surface area increase (112.58 m2/g). The EDX analysis confirms the carbonization of PS to CPS and the successful impregnation of Fe3O4 nanoparticles. CPSMNPs showed excellent adsorption efficiency, i.e., 94% for adsorption of MY of 10 mL of 100 ppm MY at optimum conditions. Kinetics data fit pseudo-second-order kinetics. The Langmuir isotherm better represents the equilibrium data with the spontaneous sorption process. This study investigates that the synthesized nanoparticles have an excellent texture and can be used as a special adsorbent for the adsorption of wastewater pollutants like MY

Viscosine as a Potent and Safe Antipyretic Agent Evaluated by Yeast-Induced Pyrexia Model and Molecular Docking Studies

The antipyretic potential of viscosine, a natural product isolated from the medicinal plant Dodonaea viscosa, was investigated using yeast-induced pyrexia rat model, and its structure-activity relationship was investigated through molecular docking analyses with the target enzymes cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), and microsomal prostaglandin E synthase-1 (mPGES-1). The in vivo antipyretic experiments showed a progressive dose-dependent reduction in body temperatures of the hyperthermic test animals when injected with viscosine. Comparison of docking analyses with target enzymes showed strongest bonding interactions (binding energy -17.34 kcal/mol) of viscosine with the active-site pocket of mPGES-1. These findings suggest that viscosine shows antipyretic properties by reducing the concentration of prostaglandin E2 in brain through its mPGES-1 inhibitory action and make it a potential lead compound for developing effective and safer antipyretic drugs for treating fever and related pathological conditions. Copyright © 2019 American Chemical Society

Kinetic, Thermodynamic and Adsorption Isotherm Studies of Detoxification of Eriochrome Black T Dye from Wastewater by Native and Washed Garlic Peel

Eriochrome Black T (EBT) is mutagenic and carcinogenic, and thus its presence in water may result in severe illnesses. This study was aimed at adsorbing EBT from simulated water samples by using a batch adsorption process, onto native (GP) and washed garlic peel (WGP). Surface and structural characterization of native and washed GP was performed using FTIR, SEM, BET, and BJH analysis. The effects of several parameters, affecting the process of adsorption, like pH, temperature, contact time, adsorbent dose, and initial dye concentration, were also examined. Freundlich and Langmuir isotherms were applied to the equilibrium data. Pseudo-first and pseudo-second order models were used to study the adsorption kinetics. The Langmuir isotherm and pseudo-second order model perfectly explained the equilibrium data. ΔG°, ΔH°, ΔS° studies indicated that adsorption of EBT onto GP and WGP was a favorable, spontaneous, and physical process. Maximum dye removal by GP (96%) and WGP (82%) was observed at pH 2. Similarly Maximum adsorption capacities were found to be 99.5 mg/g and 89.4 mg/g for GP and WGP, respectively. It is concluded from these results that garlic peel can be used as a cheaper and more efficient material for the adsorptive removal of EBT from contaminated water samples

The Druggable Pocketome of Corynebacterium diphtheriae: A New Approach for in silico Putative Druggable Targets

Diphtheria is an acute and highly infectious disease, previously regarded as endemic in nature but vaccine-preventable, is caused by Corynebacterium diphtheriae (Cd). In this work, we used an in silico approach along the 13 complete genome sequences of C. diphtheriae followed by a computational assessment of structural information of the binding sites to characterize the “pocketome druggability.” To this end, we first computed the “modelome” (3D structures of a complete genome) of a randomly selected reference strain Cd NCTC13129; that had 13,763 open reading frames (ORFs) and resulted in 1,253 (∼9%) structure models. The amino acid sequences of these modeled structures were compared with the remaining 12 genomes and consequently, 438 conserved protein sequences were obtained. The RCSB-PDB database was consulted to check the template structures for these conserved proteins and as a result, 401 adequate 3D models were obtained. We subsequently predicted the protein pockets for the obtained set of models and kept only the conserved pockets that had highly druggable (HD) values (137 across all strains). Later, an off-target host homology analyses was performed considering the human proteome using NCBI database. Furthermore, the gene essentiality analysis was carried out that gave a final set of 10-conserved targets possessing highly druggable protein pockets. To check the target identification robustness of the pipeline used in this work, we crosschecked the final target list with another in-house target identification approach for C. diphtheriae thereby obtaining three common targets, these were; hisE-phosphoribosyl-ATP pyrophosphatase, glpX-fructose 1,6-bisphosphatase II, and rpsH-30S ribosomal protein S8. Our predicted results suggest that the in silico approach used could potentially aid in experimental polypharmacological target determination in C. diphtheriae and other pathogens, thereby, might complement the existing and new drug-discovery pipelines

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<p>Diphtheria is an acute and highly infectious disease, previously regarded as endemic in nature but vaccine-preventable, is caused by Corynebacterium diphtheriae (Cd). In this work, we used an in silico approach along the 13 complete genome sequences of C. diphtheriae followed by a computational assessment of structural information of the binding sites to characterize the “pocketome druggability.” To this end, we first computed the “modelome” (3D structures of a complete genome) of a randomly selected reference strain Cd NCTC13129; that had 13,763 open reading frames (ORFs) and resulted in 1,253 (∼9%) structure models. The amino acid sequences of these modeled structures were compared with the remaining 12 genomes and consequently, 438 conserved protein sequences were obtained. The RCSB-PDB database was consulted to check the template structures for these conserved proteins and as a result, 401 adequate 3D models were obtained. We subsequently predicted the protein pockets for the obtained set of models and kept only the conserved pockets that had highly druggable (HD) values (137 across all strains). Later, an off-target host homology analyses was performed considering the human proteome using NCBI database. Furthermore, the gene essentiality analysis was carried out that gave a final set of 10-conserved targets possessing highly druggable protein pockets. To check the target identification robustness of the pipeline used in this work, we crosschecked the final target list with another in-house target identification approach for C. diphtheriae thereby obtaining three common targets, these were; hisE-phosphoribosyl-ATP pyrophosphatase, glpX-fructose 1,6-bisphosphatase II, and rpsH-30S ribosomal protein S8. Our predicted results suggest that the in silico approach used could potentially aid in experimental polypharmacological target determination in C. diphtheriae and other pathogens, thereby, might complement the existing and new drug-discovery pipelines.</p