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Metformin is a drug commonly used for the treatment of type 2 diabetes. However, it has been associated with damaging side effects when used over a long period of time. A potential solution to this problem is the implementation of a prolonged-release system for metformin, which would enhance the efficiency of the doses administered to patients. To achieve this, it is necessary to use materials compatible with humans. Electrospinning is an efficient technique that can be employed for this purpose, utilizing solvents that are safe for human use. Therefore, the objective of this study was to prepare and characterize a system for the prolonged release of metformin from zein and gelatin through coaxial electrospinning as well as to investigate its in vitro release. Metformin-loaded zein/gelatin coaxial nanofibers were prepared using the coaxial electrospinning technique and then characterized by morphological, structural, and thermal analysis. Morphologically, metformin-loaded zein/gelatin coaxial nanofibers were obtained with an average diameter of 322.6 ± 44.5 nm and a smooth surface. Fourier transform infrared spectroscopy (FTIR) analysis showed band shifts at a higher wavenumber due to drug-protein interactions by hydrogen bonding between N-H and C=O groups. Thermal gravimetric analysis (TGA) results suggested a possible interaction between materials due to an increase in the degradation temperatures of zein and gelatin when metformin was included. The transition of the crystallinity of metformin to the amorphous form was also confirmed by differential scanning calorimetry (DSC). Coaxial nanofibers exhibited an encapsulation efficiency of 66% and a profile release that showed an initial release of metformin (40%) in the first hour, followed by a gradual release until it reached equilibrium at 60 h and a cumulative release of 97% of metformin. It was concluded that using the coaxial electrospinning technique, it is possible to obtain nanofibers from polymeric solutions of zein and gelatin to encapsulate metformin, with a potential application as a prolonged-release system., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Urea is the nitrogen-containing fertilizer most used in agricultural fields; however, the nutrient given by the urea is lost into the environment. The aim of this research was to determine the effect of two soil textures by applying a prolonged-release system of urea (PRSU) on the N losses. This research shows an important decrease of the nitrate and ammonium losses from 24.91 to 87.94%. Also, the microbiological population increases after the application of the PRSU. It was concluded that both soil textures presented the same loss-reduction pattern, where the N from the nitrates and ammonium was reduced in the leachates, increasing the quality of the soil and the microbial population in both soil textures after the PRSU application., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Betalains are pigments that have properties that benefit health, such as antioxidant, anticancer, and antimicrobial activity, and they also possess a high ability to provide color. However, these pigments, although used as colorants in certain foods, have not been able to be potentialized to diverse areas such as pharmacology, due to their instability to physicochemical factors such as high temperature, pH changes and high water activity. For this reason, different stabilization methods have been reported. The method that has presented best results for diversifying the use of betalains has been encapsulation. Encapsulation is a method of entrapment where the objective is to protect a compound utilizing more stable matrices from encapsulation technologies. This method has been employed to provide greater stability to betalains, using different matrices and encapsulation technologies. However, a review does not exist, to our knowledge, which analyzes the effect of matrices and encapsulation technologies on betalains stabilization. Therefore, the objective of this review article was to evaluate the different matrices and encapsulation techniques that have been employed to stabilize betalains, in order to arrive at specific conclusions concerning the effect of encapsulation on their stabilization and to propose new techniques and matrices that could promote their stabilization., (© Association of Food Scientists & Technologists (India) 2019.)

Stenocereus thurberi is an endemic species in northwestern Mexico. It produces colorful fruits called pitayas that have an edible pulp. They have phytochemical compounds associated with biological activities. Ultrafiltration is a widely used method for the clarification of fruit juices and the recovery of phytochemicals. However, its effect has not been extensively studied in extracts. Therefore, the objective of this work is to study the effect of the ultrafiltration of pitaya extract ( Stenocereus thurberi ) on its phytochemical content, antioxidant capacity, and identification of phenolic compounds by UPLC-DAD-MS, providing greater knowledge about the pitaya. In this study, two extracts were analyzed, the unclarified extract (UE) and the clarified extract (CE). The antioxidant capacity was higher in the CE with 15.93 ± 0.42 mM TE/g, DPPH and 18.37 ± 0.016 mM TE/g, ABTS. The UPLC-MS analysis indicated the decrease in phenolic compounds in the CE and the presence of gallic acid and resorcinol, compounds that had not been identified in other species of Stenocereus spp. The correlation analysis indicated that all the phytochemicals present in the pitaya contribute significantly to the antioxidant capacity. The ultrafiltration process could be a viable option to improve the biological activity of the natural extracts.

Quercetin is a hydrophobic flavonoid with high antioxidant activity. However, for biological applications, the bioavailability of quercetin is low due to physiological barriers. For this reason, an alternative is the protection of quercetin in matrices of biopolymers as zein. The objective of this work was to prepare and characterize quercetin-loaded zein nanoparticles by electrospraying and its study of in vitro bioavailability. The physicochemical parameters such as viscosity, density, and electrical conductivity of zein solutions showed a dependence of the ethanol concentration. In addition, rheological parameters demonstrated that solutions of zein in aqueous ethanol present Newtonian behavior, rebounding in the formation of nanoparticles by electrospraying, providing spherical, homogeneous, and compact morphologies, mainly at a concentration of 80% (v/v) of ethanol and of 5% (w/v) of zein. The size and shape of quercetin-loaded zein nanoparticles were studied by transmission electron microscopy (TEM), observing that it was entrapped, distributed throughout the nanoparticle of zein. Analysis by Fourier transform-infrared (FT-IR) of zein nanoparticles loaded with quercetin revealed interactions via hydrogen bonds. The efficacy of zein nanoparticles to entrap quercetin was particularly high for all quercetin concentration evaluated in this work (87.9 ± 1.5% to 93.0 ± 2.6%). The in vitro gastrointestinal release of trapped quercetin after 240 min was 79.1%, while that for free quercetin was 99.2%. The in vitro bioavailability was higher for trapped quercetin (5.9%) compared to free quercetin (1.9%), than of gastrointestinal digestion. It is concluded, that the electrospraying technique made possible the obtention of quercitin-loaded zein nanoparticles increasing their bioavailability. PRACTICAL APPLICATION: This type of nanosystems can be used in the food and pharmaceutical industry. Quercetin-loaded zein nanoparticles for its improvement compared to free quercetin can be used to decrease the prevalence of chronic degenerative diseases by increasing of the bioavailability of quercetin in the bloodstream. Other application can be as an antioxidant system in functional foods or oils to increase shelf life., (© 2019 Institute of Food Technologists®.)

Currently, electrospraying is a novel process for obtaining the nanoparticles from biopolymers. Zein nanoparticles have been obtained by this method and used to protect both hydrophilic and hydrophobic antioxidant molecules from environmental factors. The objective of this work was to prepare and characterize gallic acid-loaded zein nanoparticles obtained by the electrospraying process to provide protection to gallic acid from environmental factors. Thus, it was related to the concentration of gallic acid in physicochemical and rheological properties of the electrosprayed solution, and also to equipment parameters, such as voltage, flow rate, and distance of the collector in morphology, and particle size. The physicochemical properties showed a relationship in the formation of a Taylor cone, in which at a low concentration of gallic acid (1% w/v), low viscosity (0.00464 ± 0.00001 Pa·s), and density (0.886 ± 0.00002 g/cm 3 ), as well as high electrical conductivity (369 ± 4.3 µs/cm), forms a stable cone-jet mode. The rheological properties and the Power Law model of the gallic acid-zein electrosprayed solution demonstrated Newtonian behavior (n = 1). The morphology and size of the particle were dependent on the concentration of gallic acid. Electrosprayed parameters with high voltage (15 kV), low flow rate (0.1 mL/hr), and short distance (10 cm) exhibited a smaller diameter and spherical morphology. FT-IR showed interaction in the gallic acid-loaded zein nanoparticle by hydrogen bonds. Therefore, the electrospraying process is a feasible technique for obtaining gallic acid-loaded zein nanoparticles and providing potential protection to gallic acid from environmental factors., (© 2019 Institute of Food Technologists®.)

Micro- and nanotechnology are tools being used strongly in the area of food technology. The electrospray technique is booming because of its importance in developing micro- and nanoparticles containing an active ingredient as bioactive compounds, enhancing molecules of flavors, odors, and packaging coatings, and developing polymers that are obtained from food (proteins, carbohydrates), as chitosan, alginate, gelatin, agar, starch, or gluten. The electrospray technique compared to conventional techniques such as nanoprecipitation, emulsion-diffusion, double-emulsification, and layer by layer provides greater advantages to develop micro- and nanoparticles because it is simple, low cost, uses a low amount of solvents, and products are obtained in one step. This technique could also be applied in the agrifood sector for the preparation of controlled and/or prolonged release systems of fertilizer or agrochemicals, for which more research must be conducted.