Abstract The chemically complex essential oils of Baccharis species are associated with several biological activities, such as antimicrobial and antiulcerous properties. However, few studies have investigated Baccharis erioclada DC. Therefore, in this study, we aimed to characterize the essential oil of B. erioclada and evaluate its antioxidant, antimicrobial, and hemolytic potential. The essential oil was extracted by hydrodistillation using a Clevenger apparatus and analyzed via gas chromatography-mass spectrometry (GC-MS). Phosphomolybdenum complex formation, reducing antioxidant power, and thiobarbituric acid reactive substances (TBARS) methods were used to determine antioxidant potential. To evaluate the essential oil’s antimicrobial activity, minimum inhibitory concentrations (MIC) in Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans were calculated. Hemolytic activity was determined in sheep red blood cells. Thirty-one compounds were identified via GC-MS analysis, representing 81.60% of the total essential oil. These compounds included: turmerone (27.97%), fokienol (13.47%), ledol (9.78%), and santalol (5.35%). The class of compounds identified was the oxygenated sesquiterpenes (62.52%). Antioxidant activity was confirmed via phosphomolybdenum complex formation and TBARS methods. Moderate antimicrobial activity and low hemolysis rates were displayed at concentrations of 250 and 500 μg/mL.

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).

Abstract Eucalyptus species possess anti-inflammatory, antifungal, antibacterial, and insecticidal properties. In this study, the chemical composition and biological activities of Eucalyptus cinerea essential oil (EO) and the leaf and stem anatomy were investigated. EO was extracted by Clevenger apparatus and the compounds were identified by GC/MS. The antioxidant activity was evaluated by DPPH, ABTS, and reducing phosphomolybdenum complex. Broth microdilution was used to determine antimicrobial activity. Cytotoxicity was verified against HeLa, HRT-18, and Calu-3 cells by MTT assay. The cytotoxic mechanism was studied by cell DNA content, cell cycle, and DNA fragmentation. The microscopic analyzes of the leaves and the stems were performed by light microscopy, field emission scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The main constituent of the EO was 1,8-cineole (55.24%). The EO showed low antioxidant and antimicrobial activities. Calu-3 cells showed a significant reduction in viability with IC50 of 689.79 ± 29.34 μg/mL. EO at 1000 μg/mL decreased the DNA content in Jurkat cells. In general, EO increased cell percentage in sub-G0 and S phases with concomitant reduction of cell percentage in G0/G1 and G2/M phases and provided DNA fragmentation of 29.73%. Anatomical and micromorphological features of the leaves and stems can help in the species identification and its differentiation from other Eucalyptus species.

Abstract Ocotea porosa (Nees & Mart.) Barroso, commonly known as “imbuia”, “canela-imbuia” or “imbuia-amarela” in Brazil, is a tree of the Southern Atlantic Forest. The present study investigates the anatomy of leaf and stem, volatile oil chemistry, as well as cytotoxicity and insecticidal activities of the essential oil of O. porosa. Species identification was achieved by anatomy features, mainly due to paracytic and anomocytic stomata; non-glandular trichomes; biconvex midrib and petiole with a collateral open arc vascular bundle; presence of a sclerenchymatous layer, starch grains and crystal sand in the stem; and the presence of phenolic compounds in the epidermis, phloem and xylem of the midrib, petiole and stem. The main volatile components of the essential oil were α-pinene (19.71%), β-pinene (13.86%) and bicyclogermacrene (24.62%). Cytotoxicity against human cancer cell (MCF-7), mouse cancer cell (B16F10) and mouse non-tumoral cell (McCoy) was observed as well as insecticidal activity of the essential oil against susceptible ‘Ft. Dix’ bed bugs (Cimex lectularius L.) by topical application.

Abstract This study aimed to investigate the anatomy and histochemistry of Mollinedia clavigera leaves and stems through photonic microscopy and scanning electron microscopy. Noteworthy features of leaves were: presence of paracytic stomata on both surfaces; simple as well as bifurcate non-glandular trichomes; prismatic calcium oxalate crystals; flat-convex midrib with a central and two dorsal bundles; concave-convex petiole with a single vascular bundle in open archh. Stems were cylindrical and showed prismatic and styloid crystals in the pith. Histochemical analysis detected lipophilic and phenolic compounds, starch grains and lignified elements such as brachysclereids and fibers. These features may assist in future identifications and quality control of M. clavigera, avoid misidentification between other genus members, once species and genus studies are scarce.

The objective of this work was to develop and characterize liposomes loaded with silver nanoparticles (LAgNPs) to show improvement in stability characteristics. AgNPs were prepared by the green synthesis method with Aloe vera gel extract and exposure to sunlight. Liposomes were prepared by the modified reverse phase method. Particle size, polydispersity index, zeta potential, as well as the scanning electron microscopy (SEM) morphological aspects of AgNPs and LAgNPs were evaluated. In addition, was used flame atomic absorption spectroscopy to determine the amount of AgNP that was encapsulated in liposomes. The AgNPs presented as amorphous and polydisperse structures, with a mean diameter of 278.46 nm and zeta potential of -18.3 mV. LAgNPs had a mean diameter between 321 and 373 nm, the polydispersity index close to 0.2 and a zeta potential around -40 mV, which indicates greater stability to the AgNPs. The images obtained by SEM show semicircular structures for AgNPs and well-defined spherical shape for LAgNPs. The percentage of encapsulation was between 51.81 to 58.83%. These results showed that LAgNPs were obtained with adequate physicochemical characteristics as a release system.

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.

ABSTRACT Bananas and plantains are herbaceous monocotyledonous plants belonging to the genus Musa, Musaceae, which has a widespread distribution around the world. Various parts of banana plant are commonly used in traditional medicines. Several species of Musa are reported to possess anti-inflammatory, anti-hyperglycemic and antidiabetic properties. This work is aimed at studying the morphological and anatomical characteristics of the inflorescences of Musa × paradisiaca L., that could contribute to the characterization of these species cultivated in Brazil. Plant materials were collected and prepared in accordance with standard optical microscopy techniques. Morphological characterizations were conducted using morphological descriptors for inflorescences, including some descriptors from International Plant Genetic Resources Institute for Musa spp. Microscope slides were prepared using glycol-methacrylate and were stained in toluidine blue. Main features observed for M. × paradisiaca inflorescence were amphistomatic bracts with tetracytic stomata, fiber caps next to the phloem, adaxial and abaxial uniseriate epidermis, and papillose on the abaxial face. Outer tepals have multilayer epidermis and vascular bundles aligned next to the abaxial face. Free tepal has unilayeredepidermis. Anthers are tetrasporangiate and the locules are separated by the septum. Ovary is inferior and trilocular with external unilayered and internal epidermis. The main morpho-anatomical characteristics of inflorescence of Musa × paradisiaca are highlighted in this study, contributing to provide more information about the characterization of this species cultivated in Brazil.

Abstract Metallic nanoparticles have great potential as a chemotherapeutic agent. The aim of this study was to develop and characterize silver and gold nanoparticles using a simple method, as well as evaluating the potential cytotoxic activity in relation to the K-562 cell line. For the synthesis, a solution containing the metallic ions was subjected to magnetic stirring with the aqueous extract of Lavandula dentata L. and a change of colour was observed. With the data obtained from the analyses we concluded that the nanoparticles were successfully obtained by a simple and green method using the aqueous extract of L. dentata. The obtained nanoparticles presented a reduced size, a low level of polydispersion, and a homogenous spherical shape. The nanoparticles presented intense and characteristic diffraction peaks, which could be correlated to the planes of the centred cubic structure of the silver and gold. The two formulations presented predominantly crystalline characteristics. The infrared analysis suggested that the amides and alcohols present in the samples may have been responsible for the reduction and limitation of the size and dispersion of the silver and gold nanoparticles. The cytotoxic assay showed that the nanoparticles demonstrated great potential to reduce the cell viability of the K-562 cell line, especially the gold nanoparticles.

ABSTRACT The present work provides a comparative account of the morpho-anatomy of six species of Eucalyptus, namely E. badjensis Beuzev. & Welch, E. benthamii Maiden & Cambage, E. dunnii Maiden, E. grandis W.Hill, E. globulus Labill. and E. saligna Sm., Myrtaceae. Leaf samples of these six species were investigated by light and scanning electron microscopy. The observed microscopic features that can be useful in the identification and quality control of the studied species include the morphology of epicuticular waxes, presence of prismatic crystals on the leaf surface, leaf midrib shape and arrangement of its vascular system, and the presence or absence of the sclerenchymatous fiber caps in the vascular bundle.

ABSTRACT Eucalyptus saligna Sm., Myrtaceae, commonly known as Sydney blue gum, is often confused with several other species in the genus. The leaf volatile oils of the species have been reported to have antimicrobial, insecticidal, nematicidal, repellent and cytotoxicity properties. The present work provides anatomy as well as volatile oil chemistry of the species collected from South Brazil. The anatomy and histochemistry of the leaves and stems were investigated by light and scanning electron microscopy, and the leaf and stem volatile oils were analyzed by GC–MS. Amphistomatic leaves, anomocytic stomata, presence of papillae and epicuticular waxes, slightly biconvex midrib with a bicollateral vascular bundle in open arc and two dorsal traces, secretory cavities, calcium oxalate druses and prismatic crystals, rounded petiole with a bicollateral vascular bundle in open arc with invaginated ends and rounded stem with sclerenchyma abutting the internal and external phloem are observed in this species. The main components of the volatile oil were p-cymene (28.90%) and cryptone (17.92%). These characteristics can help in the identification and quality control of E. saligna.

ABSTRACT Lavandula dentata, popularly known as lavender, is commonly used in traditional medicine for the treatment of digestive and inflammatory disorders. The objective of this study was to analyzed the chemical oil composition, antioxidant and antimicrobial activities of the essential oil and anatomical markers of the leaf and stem of L. dentata cultivated in South Brazil. Essential oil showed an antioxidant activity similar to rutin and gallic acid when analyzed by phosphomolybdenum method. However, by the free radical DPPH and ABTS methods, it showed a slight potential antioxidant. Essential oil presented 1,8-cineol (63%) as major component, antimicrobial activity against Gram-positive, Gram-negative bacteria strains and Candida albicans, by broth microdilution. The anatomical profile provided the following main microscopic markers: hypostomatic leaves; diacytic stomata, thin and striate cuticle; multicellular and branched non-glandular trichomes; capitate glandular trichomes; peltate glandular trichomes; dorsiventral mesophyll; flat-convex shape midrib, truncated on the abaxial side; one collateral vascular bundle in the midrib; square stem shape, angular collenchyma alternated with cortical parenchyma; sclerenchymatic fibers well-developed on the four edges.

Abstract Sapium belongs to Euphorbiaceae family and comprises 23 species. Sapium glandulosum (L.) Morong is popularly known in Brazil as "pau-leiteiro" and "leitosinha" and it is used in traditional medicine to cicatrisation. Its leaf extracts have shown analgesic, anti-inflammatory and antibacterial activities. The preliminary set of pharmacognostic tools used for quality assessment of medicinal plant parts is macro- and micro-anatomy and S. glandulosum has not anatomical and histochemical description. Thus the aim of this study was to investigate the anatomical and histochemical characteristics of the leaf and stem of S. glandulosum as a means of providing information for quality assessment of herbal industry. The leaves and stems were investigated by employing field emission scanning electron microscopy, light microscopy, and histochemistry techniques. The analysis showed that S. glandulosum had the following anatomical features: dorsiventral and amphistomatic leaves; paracytic stomata; tabular crystal druses; non-articulated and branched laticifers; midrib's biconvex shape with vascular systems in open arc with invaginated ends; petiole with a round shape and slight concavity on the adaxial side; six collateral vascular bundles in U-shaped organisation; a circular stem shape and a sclerenchymatous ring. In the histochemical tests lipophilic components were found in cuticle and in the latex; phenolic compounds were met in the mesophyll and in the latex; starch grains were found in the parenchymatous sheath; lignified elements were met in the sclerenchymatous ring in the cortex and in the perivascular sclerenchymatous caps, beyond in the vessel elements. These features are helpful when conducting a quality control process.

ABSTRACT Mikania belongs to the Asteraceae family and includes a wide range of promising pharmacological activities. Several species of Mikania, which is popularly known in Brazil as “guaco”, occur in Southern Brazil and their external morphology is similar. The aim of this study was to investigate the morpho-anatomical characteristics of the leaf and stem of Mikania campanulata, Mikania cordifolia, Mikania glomerata, Mikania hastato-cordata, Mikania microptera and Mikania sessilifolia as a means of providing additional support for differentiating these taxa. The leaves and stems were investigated by employing scanning electron microscopy and light microscopy techniques. The morphological features of Mikania spp. leaves make it possible to differentiate between the species; nevertheless, when the plants were fragmented or pulverized the anatomical features of the leaves and stems supplied additional helpful data in this regard. The main anatomical characteristics were presence of hypodermis and lens shaped epidermal cells, set of trichomes; midrib, petiole and stem shape and vascular pattern; sclerenchymatous ring in the cortex, sclerenchymatous cells and secretory ducts in the pith.

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.