Therapeutic applications of resveratrol nanoformulations

Resveratrol, or 3, 5, 4-trihydroxy-trans-stilbene, is a naturally occurring polyphenol present in several dietary sources such as grapes, soybeans, berries, pomegranate and peanuts. Resveratrol has received recent attention due to its diverse pharmacological activities. However, resveratrol clinical efficacy is limited due to its poor systemic bioavailability, of less than 1%, which is due to its low aqueous solubility, extensive first-pass metabolism and existence of enterohepatic recirculation. Therefore, in order to overcome these limitations, various nanocarriers including polymeric nanoparticles, solid lipid nanoparticles, liposomes, micelles and conjugates have been developed. These nanocarriers are able to enhance the bioavailability of resveratrol by modulating the P-glycoprotein, cytochrome P-450 enzymes and bypassing the hepatic first-pass effect. Here we review resveratrol nanoformulations for enhancing the efficacy of native resveratrol.     

Antimicrobial therapeutics delivery systems based on biodegradable polylactide/polylactide-co-glycolide particles

Environmental Chemistry Letters - Infectious diseases are globally associated with high mortality in spite of the availability of therapeutic agents against most pathogenic microorganisms. This is...     

Cyclodextrin-based delivery systems for dietary pharmaceuticals

Environmental Chemistry Letters - The food industry is increasingly seeking innovative solutions for enhancing the bioavailability and clinical efficacy of phytochemicals. In this regard,...     

Acetylation of Castor Meal and Castor Proteins for Thermoplastic Applications

Castor meal and proteins extracted from the castor meal have been acetylated and made into thermoplastics. Castor meal is generated as the byproduct after extraction of oil from the seeds and hence available in large volumes at low cost. The meal is also non-thermoplastic making it difficult to use for industrial applications. In this research, castor meal (CM) and castor proteins (CP) extracted from the castor meal were acetylated under alkaline conditions in order to make them thermoplastic. The acetylated products were characterized using FT-IR, P-GC-MS and DSC. The effects of various acetylation conditions on % acetyl content were studied. The highest % acetyl content obtained in the case of CM was 11.63% for a material to anhydride ratio of 1:5 at 130?°C and for CP a higher acetylation of 23.60% was obtained using a ratio of 1:5 at 120?°C. It was found that that acetylated CP could be compression molded into films.     

Cost shifting and other perverse incentives in biodiversity offsetting in India

Biodiversity offsetting aims to compensate for development‐induced biodiversity loss through commensurate conservation gains and is gaining traction among governments and businesses. However, cost shifting (i.e., diversion of offset funds to other conservation programs) and other perverse incentives can undermine the effectiveness of biodiversity offsetting. Additionality—the requirement that biodiversity offsets result in conservation outcomes that would not have been achieved otherwise—is fundamental to biodiversity offsetting. Cost shifting and violation of additionality can go hand in hand. India's national offsetting program is a case in point. Recent legislation allows the diversion of offset funds to meet the country's preexisting commitments under the United Nations Framework Convention on Climate Change (UNFCCC) and United Nations Convention on Biological Diversity (CBD). With such diversions, no additional conservation takes place and development impacts remain uncompensated. Temporary additionality cannot be conceded in light of paucity of funds for preexisting commitments unless there is open acknowledgement that fulfillment of such commitments is contingent on offset funds. Two other examples of perverse incentives related to offsetting in India are the touting of inherently neutral offsetting outcomes as conservation gains, a tactic that breeds false complacency and results in reduced incentive for additional conservation efforts, and the clearing of native vegetation for commercial plantations in the name of compensatory afforestation, a practice that leads to biodiversity decline. The risks accompanying cost shifting and other perverse incentives, if not preempted and addressed, will result in net loss of forest cover in India. We recommend accurate baselines, transparent accounting, and open reporting of offset outcomes to ensure biodiversity offsetting achieves adequate and additional compensation for impacts of development.     

Breakthrough Curves Characterization and Identification of an Unknown Pollution Source in Groundwater System Using an Artificial Neural Network (ANN)

Contamination of groundwater constrains its uses and poses a serious threat to the environment. Once groundwater is contaminated, the cleanup may be difficult and expensive. Identification of unknown pollution sources is the first step toward adopting any remediation strategy. The proposed methodology exploits the capability of a universal function approximation by a feed-forward multilayer artificial neural network (ANN) to identify the sources in terms of its location, magnitudes, and duration of activity. The back-propagation algorithm is utilized for training the ANN to identify the source characteristics based on simulated concentration data at specified observation locations in the aquifer. Uniform random generation and the Latin hypercube sampling method of random generation are used to generate temporal varying source fluxes. These source fluxes are used in groundwater flow and the transport simulation model to generate necessary data for the ANN model-building processes. Breakthrough curves obtained for the specified pollution scenario are characterized by different methods. The characterized breakthrough curves parameters serve as inputs to ANN model. Unknown pollution source characteristics are outputs for ANN model. Experimentation is also performed with different number of training and testing patterns. In addition, the effects of measurement errors in concentration measurements values are used to show the robustness of ANN based methodology for source identification in case of erroneous data.     

Correlation of edge truncation with antibacterial activity of plate-like anisotropic silver nanoparticles

Environmental Science and Pollution Research - The effect of silver nanoparticle anisotropy on the antibacterial properties has been studied against Escherichia coli, Staphylococcus aureus,...     

Kinetic and equilibrium characterization of uranium(VI) adsorption onto carboxylate-functionalized poly(hydroxyethylmethacrylate)-grafted lignocellulosics

This study investigated the feasibility of using a new adsorbent prepared from coconut coir pith, CP (a coir industry-based lignocellulosic residue), for the removal of uranium [U(VI)] from aqueous solutions. The adsorbent (PGCP-COOH) having a carboxylate functional group at the chain end was synthesized by grafting poly(hydroxyethylmethacrylate) onto CP using potassium peroxydisulphate-sodium thiosulphite as a redox initiator and in the presence of N,N'-methylenebisacrylamide as a crosslinking agent. IR spectroscopy results confirm the graft copolymer formation and carboxylate functionalization. XRD studies confirm the decrease of crystallinity in PGCP-COOH compared to CP, and it favors the protrusion of the functional group into the aqueous medium. The thermal stability of the samples was studied using thermogravimetry (TG). Surface charge density of the samples as a function of pH was determined using potentiometric titration. The ability of PGCP-COOH to remove U(VI) from aqueous solutions was assessed using a batch adsorption technique. The maximum adsorption capacity was observed at the pH range 4.0-6.0. Maximum removal of 99.2% was observed for an initial concentration of 25mg/L at pH 6.0 and an adsorbent dose of 2g/L. Equilibrium was achieved in approximately 3h. The experimental kinetic data were analyzed using a first-order kinetic model. The temperature dependence indicates an endothermic process. U(VI) adsorption was found to decrease with an increase in ionic strength due to the formation of outer-sphere surface complexes on PGCP-COOH. Equilibrium data were best modeled by the Langmuir isotherm. The thermodynamic parameters such as DeltaG(0), DeltaH(0) and DeltaS(0) were derived to predict the nature of adsorption. Adsorption experiments were also conducted using a commercial cation exchanger, Ceralite IRC-50, with carboxylate functionality for comparison. Utility of the adsorbent was tested by removing U(VI) from simulated nuclear industry wastewater. Adsorbed U(VI) ions were desorbed effectively (about 96.2+/-3.3%) by 0.1M HCl. The adsorbent was suitable for repeated use (more than four cycles) without any noticeable loss of capacity.     

Removal and recovery of uranium(VI) by adsorption onto a lignocellulosic-based polymeric adsorbent containing amidoxime chelating functional group

A new adsorbent (ABS) with amidoxime functional group was prepared through graft polymerization of acrylonitrile onto banana stem (BS) using ceric ammonium nitrate (CAN)/HNO₃ initiator system, followed by treatment with hydroxylamine hydrochloride in alkaline solution. Infrared spectroscopy, surface area analyzer, thermogravimetry, and potentiometric titration were used for the characterization of the adsorbent. Effective removal of U(VI) ions was demonstrated at the pH range 4.0–6.0. The mechanism for the removal of U(VI) ions by ABS was based on complexation adsorption model. Equilibrium was achieved in approximately 3 h. The experimental kinetic data were analyzed using first-order, second-order, and Elovich kinetic models, and are well fitted with second-order kinetics. The temperature dependence indicates an exothermic process. U(VI) adsorption was found to decrease with increase of ionic strength. The Freundlich isotherm model fitted the experimental equilibrium data well. The adsorption efficiency was tested using synthetic nuclear industry effluents. The maximum adsorption capacity for U(VI) removal was found to be 80 mg g^-1 at 20°C. Adsorbed U(VI) ions were desorbed effectively, about 99% by 0.2 M HCl. Repeated adsorption/desorption cycles show the feasibility of the ABS for the removal of U(VI) ions from water and nuclear industry effluents.