Abstract Ilex paraguariensis (Aquifoliaceae), commonly known as “yerba mate” or “erva-mate”, is a shrub or tree native to South America. The leaves of the plant are traditionally used to prepare a caffeine-rich infusion with several medicinal properties, including antirheumatic, antithrombotic, anti-inflammatory, anti-obesity, diuretic, and hypocholesterolemic. Ilex paraguariensis is adulterated with several other species of Ilex, such as I. brevicuspis, I. dumosa, and I. theezans. It is also commonly adulterated with unrelated species, such as Citronella gongonha of Cardiopteridaceae. The latter species, commonly called “false-mate”, is one of the most frequent adulterants due to its similar habit and leaf morphology. Comprehensive studies on authentication and quality control of erva-mate are still scarce. This study provides a detailed comparative anatomy of the leaves and stems of I. paraguariensis and C. gongonha by light and scanning electron microscopy. The main distinguishing characteristics are the epidermal cell wall shape, type of stomata, crystal morphotypes, stem shape, presence or absence of glandular trichomes, and sclerenchymatous sheath. This data can help in the authentication and quality control of erva-mate raw materials.

Abstract Phenolic compounds are frequently found in the specific tissues in the leaves and stems of Baccharis species. However, only a few species of the genus have been studied in recent years, including B. erioclada. This study evaluates the in vitro antioxidant potential of B. erioclada crude extract and its fractions. Phytochemical studies, including quantification of total phenolics and flavonoids have also been carried out. Crude extract presented higher antioxidant capacity since it showed lower values of IC50 or greater reductive capacity compared to the fractions. The total phenolic compounds and flavonoids in the crude extract were quantified as 160.66 mg/g and 47.98 mg/g, respectively. Hispidulin showed 27,2296 g/100 g of dried extract. The present study evidenced that B. erioclada extracts are promising sources of antioxidant compounds.

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 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 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 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.