Development and Characterization of High-Absorption Microencapsulated Organic Propolis EPP-AF® Extract (i-CAPs).

The demand for organic and functional food continues to increase yearly. Among the available functional foods, propolis is a bee product that has various beneficial properties, including antimicrobial, antioxidant, and anti-inflammatory activities. However, it generally is only available in ethanol solution, which has poor bioavailability, as it is relatively insoluble in water. The use of such ethanol extracts is often objectionable because of the alcohol content and because they have a strong and striking taste. Development of alternatives that can efficiently and safely increase solubility in water, and that meet organic production specifications, has been a challenge. To address these concerns, microcapsules were developed using spray-dryer technology from an emulsion based on EPP-AF® propolis and gum arabic (i-CAPS). These propolis-loaded microcapsules were characterized using FT-IR, SEM, TGA, HPLC, and spectrophotometric techniques, along with determination of antimicrobial, antioxidant, antitumor, anti-inflammatory, and antihypercholesterolemic activities, as well as permeability in in vitro models. The production system resulted in microcapsules with a spherical shape and an encapsulation efficiency of 93.7 ± 0.7%. They had IC50s of 2.654 ± 0.062 and 7.342 ± 0.058 µg/mL by FRAP and DPPH antioxidant methods, respectively. The EPP-AF® i-CAPS also had superior antimicrobial activity against Gram-positive bacteria. Antitumor activity was calculated based on the concentration that inhibited 50% of growth of AGS, Caco-2, and MCF-7 cell strains, giving results of 154.0 ± 1.0, 117 ± 1.0, and 271.0 ± 25 µg/mL, respectively. The microcapsule presentation reduced the permeation of cholesterol by 53.7%, demonstrating antihypercholesterolemic activity, and it improved the permeability of p-coumaric acid and artepillin C. The IC50 for NO production in RAW 264.7 cells was 59.0 ± 0.1 µg/mL. These findings demonstrate the potential of this new propolis product as a food and pharmaceutical ingredient, though additional studies are recommended to validate the safety of proposed dosages.

Antimicrobial Formulation of a Bacterial Nanocellulose/Propolis-Containing Photosensitizer for Biomedical Applications.

With the aim of contributing to the development of more efficient materials for wound care, new topical formulations based on bacterial nanocellulose (BNC) hydrogels containing propolis were produced. Characterizations confirmed the incorporation of propolis into the BNC matrix, maintaining its structure and properties. Rheological analysis confirmed that the hydrogels showed thixotropic behavior appropriate for topical application. Chromatographic profiles showed sustained release of propolis biomarkers for at least 20 h. The formulations did not present mutagenicity. For application in photodynamic inactivation (PDI), BNC/propolis hydrogels were prepared with the photosensitizers methylene blue (MB). Spectroscopy and confocal fluorescence microscopy confirmed the interaction of MB and propolis in BNC hydrogels, as well as the formation of a new composite material. In the antibacterial assays, formulations containing MB and propolis significantly reduced Staphylococcus aureus growth. In the presence of light, BNC/MB hydrogels completely inhibited the microorganism. Therefore, the results suggest potential materials for the prevention or treatment of Staphylococcus aureus infections in wounds.

Review of Bacterial Nanocellulose as Suitable Substrate for Conformable and Flexible Organic Light-Emitting Diodes.

As the development of nanotechnology progresses, organic electronics have gained momentum in recent years, and the production and rapid development of electronic devices based on organic semiconductors, such as organic light-emitting diodes (OLEDs), organic photovoltaic cells (OPVs), and organic field effect transistors (OFETs), among others, have excelled. Their uses extend to the fabrication of intelligent screens for televisions and portable devices, due to their flexibility and versatility. Lately, great efforts have been reported in the literature to use them in the biomedical field, such as in photodynamic therapy. In tandem, there has been considerable interest in the design of advanced materials originating from natural sources. Bacterial nanocellulose (BNC) is a natural polymer synthesized by many microorganisms, notably by non-pathogenic strains of Komagataeibacter (K. xylinus, K. hansenii, and K. rhaeticus). BNC shows distinct physical and mechanical properties, including its insolubility, rapid biodegradability, tensile strength, elasticity, durability, and nontoxic and nonallergenic features, which make BNC ideal for many areas, including active and intelligent food packaging, sensors, water remediation, drug delivery, wound healing, and as conformable/flexible substrates for application in organic electronics. Here, we review BNC production methods, properties, and applications, focusing on electronic devices, especially OLEDs and flexible OLEDs (FOLEDs). Furthermore, we discuss the future progress of BNC-based flexible substrate nanocomposites.

Evolução da cicatrização de lesões por pressão em tratamento com hidrogel à base de biopolímeros / Evolution of wound healing by pressure in biopolymer hydrogel treatment / Evolución de la cicatrización de lesiones por presión en el tratamiento con hidrógel de biopolímero

Introdução: Lesões por pressão têm evolução geralmente rápida, podem levar ao desenvolvimento de infecções de partes moles e demandam tratamento específico e prolongado. Objetivo: Avaliar a eficácia do hidrogel à base de celulose bacteriana no processo cicatricial de lesões por pressão. Material e Método: Estudo descritivo, observacional e prospectivo de abordagem quantitativa. Amostra composta de três pacientes com lesões por pressão de estágios III e IV, atendidos pela Secretaria de Saúde numa cidade do interior paulista. Os dados foram coletados de junho a julho de 2019 e as lesões avaliadas semanalmente. No tratamento se utilizou cobertura de hidrogel à base de celulose bacteriana, para a avaliação do processo cicatricial utilizou-se a escala de Bates-Jensen Wound Assessment Tool e as Classificações dos Resultados de Enfermagem. Os dados foram analisados pelo programa Excel. Parecer 3.337.831. Resultados: A evolução cicatricial mostrou-se adequada e significativa a cada visita, diminuindo o escore da maioria dos indicadores analisados. Conclusão: Todas as lesões apresentaram desbridamento autolítico, facilitando a remoção dos tecidos desvitalizados, além de diminuir o tamanho e a profundidade ao promover o desenvolvimento de tecido de granulação.(AU)

Introduction: Pressure injuries have generally rapid evolution, may lead to the development of soft tissue infections and require specific and prolonged treatment. Objective: To evaluate the effectiveness of hydrogel based on bacterial cellulose in the cicatricial process of pressure injuries. Material and Method: Descriptive, observational and prospective study of quantitative approach. A composite sample of three patients with stage III and IV pressure injuries, attended by the Department of Health in a city in the interior of the state of São Paulo. Data were collected from June to July 2019 and lesions were evaluated weekly. The treatment used hydrogel coverage based on bacterial cellulose, the Bates-Jensen Wound Assessment Tool and the Classification of Nursing Results were used to evaluate the cicatricial process. The data were analyzed by the Excel program. Results: The cicatricial evolution was adequate and significant at each visit, decreasing the score of most indicators analyzed. Conclusion: All lesions presented autolytic debridement, facilitating the removal of devitalized tissues, besides decreasing the size and depth while promoting the development of granulation tissue.(AU)

Introducción: Las lesiones por presión tienen una evolución generalmente rápida, pueden conducir al desarrollo de infecciones de tejidos blandos y requieren un tratamiento específico y prolongado. Objetivo: Evaluar la efectividad del hidrogel a base de celulosa bacteriana en el proceso de curación de lesiones por presión. Material y método: Estudio descriptivo, observacional y prospectivo con enfoque cuantitativo. Muestra compuesta por tres pacientes con lesiones por presión estadios III y IV, atendidos por el Departamento de Salud de una ciudad del interior de São Paulo. Los datos se recopilaron de junio a julio de 2019 y las lesiones se evaluaron semanalmente. En el tratamiento se utilizó una cubierta de hidrogel a base de celulosa bacteriana y la valoración del proceso de cicatrización mediante la Herramienta de Evaluación de Heridas Bates-Jensen y las Clasificaciones de Resultados de Enfermería. Datos analizados por el programa Excel. Opinión 3.337.831. Resultados: La evolución de la cicatrización se mostró adecuada y significativa en cada visita, disminuyendo la puntuación de la mayoría de los indicadores analizados. Conclusión: Todas las lesiones presentaron desbridamiento autolítico, facilitando la remoción de tejidos desvitalizados, además de disminuir el tamaño y profundidad al promover el desarrollo de tejido de granulación.(AU)

Antimicrobial Orthodontic Wires Coated with Silver Nanoparticles

Abstract Conventional orthodontic treatment with the use of stainless steel may be detrimental to oral health by promoting demineralizing lesions appearance and increasing adhesion and formation of bacterial biofilm, inducing the development of cavities. An alternative that has been researched to reduce the side effects of orthodontic treatment is the coating of materials with antimicrobial nanoparticles. Nanometric- sized particles increase their surface area and contact with the microbial membrane, consequently intensifying their bacteriostatic and bactericidal effect. In this work, hydrothermal synthesis, a "green" process was used to attach silver nanoparticles (AgNPs) to the surface of two different brands of orthodontic wires. The coated materials were analyzed for their physicochemical properties by scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC), which showed the distribution of AgNPs along the wires without modifying their properties. In the microbiological test, one of the brands showed a statistically significant difference in microbial adhesion and biofilm formation by Staphylococcus aureus and Streptococcus mutans. Results lead to the conclusion that antimicrobial orthodontic wires coated with silver nanoparticles through hydrothermal synthesis is a promising material for the improvement of orthodontic treatment.