A Comprehensive Review on Therapeutic Perspectives of Phytosterols in Insulin Resistance: A Mechanistic Approach

Natural products in the form of functional foods have become increasingly popular due to their protective effects against life-threatening diseases, low risk of adverse effects, affordability, and accessibility. Plant components such as phytosterol, in particular, have drawn a lot of press recently due to a link between their consumption and a modest incidence of global problems, such as Type 2 Diabetes mellitus (T2DM), cancer, and cardiovascular disease. In the management of diet-related metabolic diseases, such as T2DM and cardiovascular disorders, these plant-based functional foods and nutritional supplements have unquestionably led the market in terms of cost-effectiveness, therapeutic efficacy, and safety. Diabetes mellitus is a metabolic disorder categoriszed by high blood sugar and insulin resistance, which influence major metabolic organs, such as the liver, adipose tissue, and skeletal muscle. These chronic hyperglycemia fallouts result in decreased glucose consumption by body cells, increased fat mobilisation from fat storage cells, and protein depletion in human tissues, keeping the tissues in a state of crisis. In addition, functional foods such as phytosterols improve the body’s healing process from these crises by promoting a proper physiological metabolism and cellular activities. They are plant-derived steroid molecules having structure and function similar to cholesterol, which is found in vegetables, grains, nuts, olive oil, wood pulp, legumes, cereals, and leaves, and are abundant in nature, along with phytosterol derivatives. The most copious phytosterols seen in the human diet are sitosterol, stigmasterol, and campesterol, which can be found in free form, as fatty acid/cinnamic acid esters or as glycosides processed by pancreatic enzymes. Accumulating evidence reveals that phytosterols and diets enriched with them can control glucose and lipid metabolism, as well as insulin resistance. Despite this, few studies on the advantages of sterol control in diabetes care have been published. As a basis, the primary objective of this review is to convey extensive updated information on the possibility of managing diabetes and associated complications with sterol-rich foods in molecular aspects.     

Synthesis of crescent shaped heterocycle-fused aromatics via Garratt-Braverman cyclization and their DNA-binding studies

Three crescent shaped heterocycle-fused phenanthrene based systems 1–3 have been synthesized starting from benzene (or substituted benzene) 1,2-bis-propargyl alcohols. Bis-alkylation with propargylic bromides provided the key intermediate, the bis-propargyl bis-ethers. In spite of the possibility of many competing reactions, the latter underwent facile double Garratt-Braverman cyclization to provide compounds 1–3 in near quantitative yield, in a striking reaction involving the formation of four C–C bonds in a single step. Compounds 1–3 showed binding interaction with DNA, predominantly, via groove binding along with partial intercalation (combilexins). Molecular docking study supported the proposed binding modes.     

The reaction of chromate with diphenylcarbazide. I

The mechanism of the classical colour reaction between chromate and carbazide has been studied in solution from various physicochcmical points of view. It has been established from spectral identity that the same red-violet compound is produced in the 3 different reaction systems, chromate-carbazidc, chromate-carbazone and chromous-carbazonc. This leads to the conclusion that tlie chromate-carbazidc reaction is a composite one involving preliminary oxidation followed subsequently by complex formation. Moreover, the actual constituents involved in the reaction have been identified as Cr⁺² on the one hand and carbazone on the other, giving rise to an intensely coloured inner complex compound. The inner complex nature of the coloured product was gauged independently from migration studies and from extraction of the coloured compound by non-polar solvents.     

Recent advances in Garratt-Braverman cyclization: Mechanistic and synthetic explorations

Garratt-Braverman cyclization has emerged as one of the simplest synthetic tool to construct two consecutive CC bonds leading to the formation of various important structural scaffolds having significance in the field of therapeutics and material science. The strategic design of suitable precursor for this cycloaromatization reaction involves the deep understanding of reaction pathways involving diradicals and ions. On the other hand, the reaction offers an unprecedented mechanistic paradox for the chemists to solve. This report aims at outlining the recent mechanistic and synthetic developments with special emphasis on the research outcomes from our laboratory.     

Exploring the Antibacterial and Antibiofilm Efficacy of Silver Nanoparticles Biosynthesized Using Punica granatum Leaves

The current research work illustrates an economical and rapid approach towards the biogenic synthesis of silver nanoparticles using aqueous Punica granatum leaves extract (PGL-AgNPs). The optimization of major parameters involved in the biosynthesis process was done using Box-Behnken Design (BBD). The effects of different independent variables (parameters), namely concentration of AgNO₃, temperature and ratio of extract to AgNO_3, on response viz. particle size and polydispersity index were analyzed. As a result of experiment designing, 17 reactions were generated, which were further validated experimentally. The statistical and mathematical approaches were employed on these reactions in order to interpret the relationship between the factors and responses. The biosynthesized nanoparticles were initially characterized by UV-vis spectrophotometry followed by physicochemical analysis for determination of particle size, polydispersity index and zeta potential via dynamic light scattering (DLS), SEM and EDX studies. Moreover, the determination of the functional group present in the leaves extract and PGL-AgNPs was done by FTIR. Antibacterial and antibiofilm efficacies of PGL-AgNPs against Gram-positive and Gram-negative bacteria were further determined. The physicochemical studies suggested that PGL-AgNPs were round in shape and of ~37.5 nm in size with uniform distribution. Our studies suggested that PGL-AgNPs exhibit potent antibacterial and antibiofilm properties.     

Proton-conducting I-Carrageenan-based biopolymer electrolyte for fuel cell application

The essential part of electrochemical devices, such as fuel cells and batteries, is the polymer electrolyte with good mechanical, thermal, and chemical stability. The search for a new proton-conducting membrane with easy processability, non-toxic, and low-cost has been growing rapidly. The bio-based polymer electrolytes are now receiving much attention due to the green environment. Among the commercially available biopolymers, iota-Carrageenan (I-Carrageenan) is one of the biopolymer with good film-forming nature and with good mechanical stability. I-Carrageenan-based biopolymer membranes doped with ammonium bromide (NH₄Br) have been prepared using solution-casting technique, and distilled water is used as a solvent. The prepared I-Carrageenan-based biopolymer membranes have been characterized using FTIR, XRD, and AC impedance techniques. The complexation between the polymer and salt has been revealed by FTIR. The increase in the amorphous nature of the film due to the addition of salt has been confirmed by XRD. From AC impedance technique, the conductivity of pure I-Carrageenan has been found to be 1.46 × 10⁻⁵ S/cm. The addition of different wt% of NH₄Br increases the conductivity and reaches the highest value of 1.08 × 10⁻³ S/cm for 20% NH₄Br, and the conductivity decreases on further addition of NH₄Br due to the formation of ion aggregates.

     

The reaction of chromate with diphenylcarbazide. II

Job's method was employed for ascertaining the detailed mechanism of the chromato-carbazide reaction. Three different systems (1) chromatc-carbaxidc, (2) chromate-carbastone and (3) chromous-earbazone, leading to the formation of the same coloured complex were investigated. From studies in cquimolecular solutions, the maximum composition values for the reactions were found to be 2:3, 1:3 and 1:1, respectively. Proceeding from the assumption that the reaction (3) is a case of simple displacement, the stoichiometry of all the three systems has been formulated. The role of chromate in the chromatc-carbay.ide reaction, has been found to be primarily that of an oxidising agent followed by complex formation. The tentative formulation for the three systems is given below. (1) 2Cr⁺⁶ + 3 carbazide ? 2 [Cr⁺² carbazone^-2 complex ] + carbacliazone + 4 H⁺ (2) Cr⁺⁶ + 3 carbazone ? [Cr⁺² carbazone^-2 complex] + 2 carbadiazone + 2 H⁺ (3) Cr⁺² + carbazone ? [Cr⁺² carbazone^-2 complex] + 2 H⁺ The proposed mechanism seems to explain the relevant facts observed in the course of investigation of the three Systems, particularly the rapid discharge of the colour produced when excess of chromium was added and the greater sensitivity of carbaxide as compared to carbaxonc were accounted for, The determination of K values from studies in non-equimolccular solutions of the three reactions also corroborates the aforesaid mechanism. The apparent dissociation constant of the Cr⁺²-carbazonc complex was found to be 2.7.10^-6 and the equilibrium constants of (1) and (2) were calculated as 5.7.10^-12 and 2.3.10^-7, respectively. The existence of bivalent Cr⁺² ion in the complex molecule has also been independently confirmed from magnetochemical measurements. The molar susceptibility value of 4.6 Bohr magnetons calculated on the basis of 1:1 chromous-carbastonc ratio, indicates ionic bonding in the complex.     

An expedient synthesis of spirooxindoles incorporating 2-amino pyran-3-carbonitrile unit employing dialkyl acetone-1,3-dicarboxylates

Spirooxindoles are a class of molecules possessing significant biological effects such as antiviral, antifungal, antibacterial and anticancer properties. Herein we report a series of spirooxindole molecules having 2-amino pyran-3-carbonitrile and with two ester groups. These molecules were prepared by the reaction of dialkyl acetone-1,3-dicarboxylate and isatilidenes in the presence of triethyl amine.     

High-performance thin-layer chromatography (HPTLC) method development and validation for the estimation of curcumin and cineole

JPC – Journal of Planar Chromatography – Modern TLC - Curcumin and cineole are phytochemicals which have shown synergistic effects in allergic rhinitis (AR). The aim of the current work...     

Tamarind seed polysaccharide (TSP)-based Li-ion conducting membranes

Polysaccharide-based biopolymers have gained much attention in electrochemical devices recently. Tamarind seed polysaccharide (TSP) is a biopolymer obtained from the extract of tamarind seed. It is used as thickening and gelling agent in food and textile industries. There are no works in polymer electrolytes based on TSP in lithium-ion conducting membranes. A pure TSP membrane has been prepared by dissolving 1 g of TSP in distilled water by using solution-casting technique. The prepared biopolymer membranes are subjected to Fourier transform infrared (FTIR), X-ray diffraction (XRD), and AC-impedance techniques. FTIR analysis has been conducted to observe the possible interaction between the polymer and lithium salt based upon the changes in wave numbers of the peaks. The nature of the membrane (crystalline or amorphous) has been revealed by XRD. The electrical properties of the membranes have been analyzed by AC-impedance spectroscopy. The maximum ionic conductivity for the salt-doped membrane 1 g TSP:0.4 g lithium bromide (LiBr) has been found to be 4.83 × 10^?4 S cm^?1. The primary lithium-ion battery has been constructed using the best conductivity membrane, and the open circuit voltage (OCV) has been observed as 1.63 V.