Calendula officinalis L. flower extract-mediated green synthesis of silver nanoparticles under LED light

Abstract Silver nanoparticles (AgNPs) are among the most known nanomaterials being used for several purposes, including medical applications. In this study, Calendula officinalis L. flower extract and silver nitrate were used for green synthesis of silver nanoparticles under red, green and blue light-emitting diodes. AgNPs were characterized by Ultraviolet-Visible Spectrophotometry, Field Emission Scanning Electron Microscopy, Dynamic Light Scattering, Electrophoretic Mobility, Fourier Transform Infrared Spectroscopy and X-ray Diffraction. Isotropic and anisotropic silver nanoparticles were obtained, presenting hydrodinamic diameters ranging 90 - 180 nm, polydispersity (PdI > 0.2) and moderate stability (zeta potential values around - 20 mV)

Preparation and characterization of a novel antimicrobial film dressing for wound healing application

Antibacterial activity and good mechanical properties are some of the characteristics required for an appropriate film dressing. A novel polymer blend was developed for wound healing application. Twenty-four formulations using the polymers chitosan, poly(vinyl alcohol) and/or ɛ-Polylysine and the plasticizer glycerol were designed using factorial design and then the films were prepared by the casting/solvent evaporation method. Seventeen films were obtained among the twenty-four proposed formulations that were characterized by Field Emission Scanning Electron Microscopy (FE-SEM) and Fourier Transform Infrared Spectroscopy (FTIR). Mechanical properties, such as tensile strength (σ), elongation at break (ɛ) and Young's modulus (Y) as well as antibacterial properties were determined. The best candidate was then further analyzed with regard to porosity, Water Vapor Transmission Rate (WVTR), swelling and cytotoxicity experiments. The results showed a film with semi-occlusive characteristics, good mechanical properties and no toxic. Incorporation of ɛ-Polylysine increased antibacterial activity against gram-negative (Escherichia coli) and gram-positive (Staphylococcus aureus) bacteria

Comparative analytical micrographs of “vassouras” (Baccharis, Asteraceae)

ABSTRACT Baccharis belongs to the Asteraceae family and comprises a number of medicinal species. Baccharis brevifolia DC., B. microdonta DC., B. pauciflosculosa DC., and B. trilobata A.S. Oliveira & Marchiori, which are popularly known in Brazil as “vassouras” (“broom”), are all found in Southern Brazil. The anatomical features of the leaf and stem were investigated by employing the usual light and scanning electron microtechniques, as a means of differentiating the taxa. The following anatomical characteristics can be considered to be diagnostic: the occurrence and type of stomata, midrib, stem and crystal shapes, and the presence of the petiole.

Development and characterization of hyaluronic acid-lysine nanoparticles with potential as innovative dermal filling

ABSTRACT Skin aging causes changes such as wrinkles and flaccidity leading to a large demand for aesthetic procedures, including dermal filling. A key agent in dermal filling is hyaluronic acid (HA), which is a naturally occurring glycosaminoglycan. However, it is a hydrophilic macromolecule that experiences great difficulty in crossing the skin barrier causing most commercial formulations containing it to be injectable, which in turn brings risks since they involve an invasive technique. In that sense, the aim of this study was to develop and characterize nanoparticles obtained from ionic interaction between HA and lysine (Lys) for use as a potential agent of dermal filling for topical application, increasing and improving its applicability and safety. To this end, nanoparticles were obtained by dripping of Lys over HA under magnetic stirring. A nanometric size was confirmed and a suitable surface charge was obtained by zeta potential. Nanoparticles were almost spherical in shape with a smooth surface. Interaction between raw materials for preparing nanoparticles was studied by FTIR and NMR spectroscopy and an ionic interaction was confirmed. These physicochemical features suggest that obtained nanoparticles can be further used as a topical dermal filling.

Pharmacobotanical study of Baccharis pentaptera

AbstractBaccharis L. sect. Caulopterae, Asteraceae, comprises thirty species in Brazil that show stems represented by cladodes, which are very similar in morphology. These species are popularly known as “carqueja” in Brazil and Argentina and are used in popular medicine as diuretic and stomachic. The aim of this work was to examine the morpho-anatomical characters of cladodes of Baccharis pentaptera (Less.) DC. for diagnosis purposes. The plant material was prepared by light and scanning electron microscopy. B. pentaptera shows opposite and spread wings in the two-winged cladode axis and irregular arrangement in the three-winged cladode. The wings have a uniseriate epidermis with palisade parenchyma next to both sides of epidermis. The spongy parenchyma crossed by minor collateral vascular bundles is observed in the central region of wings. The glandular trichomes are capitate and biseriate and the non-glandular trichomes are uniseriate and flagelliform with 2–3 cells that extend from the base. In caulinar axis, there are uniseriate epidermis, chlorenchyma alternating with angular collenchyma and perivascular fiber caps adjoining the phloem which is outside the xylem. Prismatic and styloid crystals are verified in the perimedullary zone. These combined characters can assist the diagnosis of Baccharis species sect. Caulopterae.

Anatomia foliar de Corymbia calophylla (Lindl.) K.D.Hill & L.A.S. Johnson, Myrtaceae / Leaf anatomy of Corymbia calophylla (Lindl.) K.D. Hill e L.A.S. Johnson (Myrtaceae)

Corymbia pertence à família Myrtaceae e envolve mais de 100 espécies arbóreas. Particularmente, a espécie Corymbia calophylla (Lindl.) K.D.Hill & L.A.S. Johnson é um dos taxa transferidos de Eucalyptus para Corymbia, com utilização para a fabricação de mobiliário requintado e para o tratamento de disfunções digestivas, segundo a medicina tradicional australiana. O presente trabalho teve por objetivo avaliar as características anatômicas da folha de C. calophylla, a partir de espécimes coletados na Embrapa Florestas (Colombo-PR, Brasil). As análises anatômicas foram conduzidas a partir dos métodos usuais de microscopia fotônica e microscopia eletrônica. A anatomia foliar revelou a presença de estômatos anomocíticos na face abaxial da folha, mesofilo dorsiventral e nervura mediana com cavidades secretoras inseridas no sistema vascular. Em secção transversal, o pecíolo apresentou formato plano-convexo. Na estrutura anatômica do limbo foliar, da nervura mediana e do pecíolo foram observadas cavidades secretoras contendo material de natureza lipofílica, além de idioblastos de conteúdo fenólico. Alguns idioblastos contendo drusas de oxalato de cálcio foram também observados no parênquima da nervura mediana de C. calophylla.

Corymbia, a genus of Myrtaceae, shows more than 100 tree species. In particular, Corymbia calophylla (Lindl.) K.D.Hill & L.A.S. Johnson is one of the taxa changed from Eucalyptus to Corymbia. C. calophylla has been used for fine furniture and for treating digestive upsets according to the Australian traditional medicine. The goal of this paper was to study the anatomical data of leaves from C. calophylla. The botanical material was collected from Embrapa Forest (Colombo-PR, Brazil). The anatomical analyses were performed by the usual light and scanning microtechniques. Anomocytic stomata were observed on the abaxial surface. The foliar blade showed dorsiventral mesophyll. Midrib having secretory cavities included on the vascular system was seen. In transection, a plane-convex petiole was found. Secretory cavities with oil content were verified in the anatomical structures of the foliar blade, midrib and petiole, as well as idioblasts with phenolic substances. Some calcium oxalate druses were observed in parenchymatous tissue of the midrib of C. calophylla.