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 The plant species identification process is one of the most critical stages of quality control of plant raw material. Microscopy serves as the most accessible means for this purpose. Epidermal appendages, such as trichomes, are important botanical markers of plant drugs, taking into account their presence or absence and micromorphology. Trichomes are useful in detecting adulterants or substitutes and in authenticating plant raw materials. The genus Solidago includes two morphologically similar South American species, S. chilensis Meyen and S. microglossa DC. (syn. S. chilensis var. megapotamica). The two species belong to the “S. chilensis” complex and are commonly called arnica-do-mato or arnica. They are morphologically separated primarily on the basis of the average length of the non-glandular trichomes present in the stems. The objective of this study was to search for microscopic markers for the identification and differentiation of these two species to support species identification and quality control of the vegetable raw material. For this purpose, the usual techniques of light and scanning electron microscopy were used. Five types of trichomes were found in this study: I. Simple non-glandular trichome, II. Uniseriate non-glandular trichome, III. Biseriate non-glandular trichome, IV. Flagelliform glandular trichome, and V. Capitate glandular trichome. S. chilensis has simple non-glandular, flagelliform glandular, and rarely capitate glandular trichomes. Whereas, in addition to its glandular trichomes, S. microglossa has two types of non-glandular trichomes: biseriate and uniseriate. Thus, the two South American species of Solidago can be microscopically identified and differentiated based on the presence and absence of the characteristic trichomes. These differences can serve as pharmacognostic subsidies for quality control of the evaluated species.

Abstract In the quality control of herbal drugs, analysis of microscopy structures is crucial to detect any adulterants or substitutes. Microscopic analysis is considered one of the first pharmacopeial parameters of pharmacognostic identification. Cecropia pachystachya Trécul (Urticaceae), commonly known as “embaúba” or Ambay pumpwood, is a broadleaved tree species native to South America, from Brazil to Argentina. Cecropia pachystachya is used in traditional medicine as a diuretic, antiasthmatic, antidiabetic, anti-inflammatory, and anti-hypertensive. Due to the malpractice of adulterating botanicals with other species having similar morphology and therapeutic uses, an unrelated plant Tetrapanax papyrifer (Hook.) K. Koch (Araliaceae) is commonly used as an adulteration of C. pachystachya. Tetrapanax papyrifer was introduced into Brazil and utilized in folk medicine as an antidiarrheal, antitussive, anti-inflammatory, and expectorant. This work aimed to identify and differentiate between the two species using microscopic features of the leaf epidermis. The presence or absence and the morphotype of trichomes are sufficient to identify and differentiate between these species, in whole or pulverized form.

Abstract Baccharis articulata (Lam.) Pers., popularly known as carqueja, carquejinha or carqueja-doce, is a plant widely used in traditional medicine as a diuretic, digestive and antidiabetic. Due to its similar morphology with other species of the "carqueja group", especially Baccharis pentaptera (Less.) DC., it can be easily confused even by specialists. Thus, this study aimed to characterize micromorphology of the crystals present in B. articulata to show botanical markers that can help differentiate this species from other carquejas. Eleven crystalline morphotypes, including druses, styloids and various shapes of prismatic and sand crystals, were evidenced by scanning electron microscopy. In addition, the elemental chemical composition and the degree of hydration of the crystals were analyzed by EDS and Raman spectroscopy. The results of this study would aid in the authentication of B. articulata and serve as a basis for future studies of other species of Baccharis.

Abstract Acmella bellidioides (Asteraceae), commonly known as "arnica-do-campo", is a South American native medicinal plant mainly found in Brazil, Argentina, Uruguay and Paraguay. The indigenous people in these regions use the flowers of this plant to treat diseases of the digestive, musculoskeletal and sensory systems. Many Acmella species are morphologically similar, and there are a few anatomical studies available in the literature that can be used to identify and distinguish them. Several other members of Asteraceae, such as Calea uniflora, Chaptalia nutans, Porophyllum ruderale, Pseudobrickellia brasiliensis and Solidago chilensis, are also called "arnica-do-campo" or "arnica". Applying the same common name to several other species makes it difficult to identify the plant correctly and allows it to be more easily adulterated. The present study characterizes A. bellidioides using microscopy and microchemical techniques to provide pharmacobotanical data to support the authentication of the species. The notable anatomical markers identified in A. bellidioides are hypostomatic leaves, anomocytic stomata, peltate glandular trichomes on the leaf abaxial surface, midrib vascular system with three collateral bundles in an open arch, and the presence of prismatic crystals in the leaves and stems. These characteristics can help species identification and differentiation of A. bellidioides from other Acmella species and Asteraceae species known as arnica-do-campo.

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 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.

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 investigates the leaf and stem anatomy, chemical composition and insecticidal activities (against Cimex lectularius Linnaeus, 1758) of the volatile oils of Schinus molle L., Anacardiaceae, a Brazilian native traditional medicinal plant. Noteworthy micro-morphological features that can help in the identification and quality control of the species include the presence of isobilateral and amphistomatic leaves, anomocytic and cyclocytic stomata, capitate glandular and conical non-glandular trichomes, large secretory ducts in the midrib, presence of druses and prismatic crystals, and the petiole vascular system comprising of five vascular bundles arranged in U-shape and an additional dorsal bundle. The major components of the volatile oil include β-pinene (14.7%), α-pinene (14.1%), limonene (9.4%) and muurolol (11.8%). Insecticidal activities of the volatile oil against bed bugs were investigated for the first time; strong toxicity by fumigation with the volatile oil of S. molle was observed and reported herein.

ABSTRACT Fadogia agrestis Schweinf. ex Hiern (Vangueria agrestis (Schweinf. ex Hiern) Lantz), Rubiaceae, is an African traditional medicinal plant also used as a dietary supplement in the US. The present paper is the first report of the pharmacognostic study of the leaf, stem and root of F. agrestis by microscopy, HPTLC and total phenolic/flavonoid content analyses. Noteworthy microscopic features that can help in identification and quality control are septate and lignified non-glandular trichomes on leaf and stem epidermises, paracytic stomata on leaf abaxial epidermis, numerous cells containing yellow substances of presumably phenolic compounds in leaf and stem, calcium oxalate druses and prismatic crystals in leaf and styloids in stem, primary phloem fibers in stem, brachysclereids in stem and root, spherical starch grains in root, and vessels with vestured pits and simple perforated end walls. In addition to microscopy, a total phenolic/flavonoid content determination and an HPTLC method were also developed for rapid chemical fingerprint analyses of Fadogia samples and dietary supplements.

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 Piper caldense C. DC., Piperaceae, commonly known as “pimenta-d’água”, “pimenta-darda” or “paguarandy” in Brazil, is a shrub that grows mainly in humid and shaded habitats. The present study investigates the anatomy of the leaves and stems of P. caldense by light and scanning electron microscopy in order to provide supporting data for correct identification of the species. The leaves are hypostomatic, have a 2-layered hypodermis, and posses pearl glands. The midrib shows a ‘U’-shaped stele comprised of about ten collateral vascular bundles. The main anatomical marker of the stem is the presence of a continuous sclerenchymatous sheath in the pith. Two forms of calcium oxalate crystals, namely crystal sand and raphides, are observed in this species.