Eucalyptus cinerea: Microscopic Profile, Chemical Composition of Essential Oil and its Antioxidant, Microbiological and Cytotoxic Activities

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.

Ocotea porosa: Anatomy and Histochemistry of Leaves and Stems, Chemical Composition, Cytotoxicity and Insecticidal Activities of Essential Oil

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.

Anatomy and Histochemistry of Leaf and Stem of Brazilian Endemic Species Mollinedia clavigera Tul

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.

Schinus molle: anatomy of leaves and stems, chemical composition and insecticidal activities of volatile oil against bed bug (Cimex lectularius)

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.

Microscopic characterization and HPTLC of the leaves, stems and roots of Fadogia agrestis - an African folk medicinal plant

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.

Comparative leaf morpho-anatomy of six species of Eucalyptus cultivated in Brazil

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.

Anatomy and volatile oil chemistry of Eucalyptus saligna cultivated in South Brazil

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.

Anatomy and microscopy of Piper caldense, a folk medicinal plant from Brazil

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.