Abstract: Background: The leaves of many species of Maytenus are used to prepare herbal drugs to treat stomach ulcers. Questions: In order to define key anatomical characters for the unambiguous species identification, the present study aimed to describe the leaf morphoanatomy of M. imbricata. Species study: Maytenus imbricata Mart. ex Reissek (Celastraceae) Study site and dates: Collected in an area of ‘campo rupestre’ - one of the Brazilian Savannah vegetation (20º 22’ 11.02” S, 43º 30’ 22.81” W) in August 2015. Methods: The plant material was processed according to commonly used techniques in plant anatomy studies. Results: The major anatomical characters for several species of Maytenus identification also present in M. imbricata are marginal teeth, conspicuous epicuticular wax, ciclocytic stomata, thick external periclinal wall with large pits on epidermal cells and vascular system with a closed loop shape in cross-section. Strips on the anticlinal walls on epidermal cells and conspicuous gelatinous fibers sheath are diagnostic for M. imbricata. Conclusions: Strips on the anticlinal wall of the epidermal cell are reported for the first time for the genus. The xeromorphic traits help the species to survive in arid environments and may contribute to quality control of the raw material used in the production of herbal medicines.

Resumen: Antecedentes: Las hojas de muchas especies de Maytenus se utilizan para la preparación de medicamentos para el tratamiento de las úlceras de estómago. Preguntas: Con la finalidad de contribuir a la identificación de la especie, este estudio tuvo como objetivo describir la morfología y anatomia de la hoja de M. imbricata. Especie de estudio: Maytenus imbricata Mart. ex Reissek (Celastraceae) Sitio y años de estudio: Recolecta de material en una zona de ‘campo rupestre’ - vegetación del cerrado brasileño (20º 22’ 11.02” S, 43º 30’ 22.81” W) en agosto del 2015. Métodos: El material vegetal se procesó mediante las técnicas que se utilizan en los estudios de anatomía vegetal. Resultados: Los principales caracteres anatómicos para la identificación de varias especies de Maytenus, que están presentes en M. imbricata, son los dientes marginales, la cera epicuticular gruesa, los estomas ciclocíticos, las células epidérmicas con la pared periclinal externa gruesa, con grandes punteaduras y la sección transversal del sistema vascular en un círculo cerrado. Las estrías en las paredes anticlinales y las fibras gelatinosas son caracteres diagnósticos para M. imbricata. Conclusiones: Las estrías que se forman en la pared de las células epidérmicas se reportan por primera vez en el género. Estos caracteres xeromórficos ayudan a la especie a sobrevivir en ambientes áridos y pueden contribuir al control de la calidad de la materia prima utilizada en la producción de medicamentos.

Dois novos friedelanos, 1 e 2, e cinco triterpenos pentacíclicos conhecidos foram isolados dos galhos de Maytenus robusta. Suas estruturas químicas foram identificadas como 3,16-dioxo-29-hidroxifriedelano (1), 3-oxo-16b,29-di-hidroxifriedelano (2), 3-oxofriedelano (3), 3b-friedelinol (4), 3,16-dioxofriedelano (5), 3-oxo-29-hidroxifriedelano (6) e 3,16-dioxo-12a-hidroxifriedelano (7). A estrutura e estereoquímica dos triterpenos 1 e 2 foram estabelecidas por infravermelho (IR), ressonância magnética nuclear (NMR) 1D/2D, espectrometria de massas de alta resolução com ionização química à pressão atmosférica (HR-APCIMS) e difração de raios X de pó. A atividade citotóxica in vitro dos triterpenos 1 a 6 foi avaliada frente a células de câncer de mama murino. Os triterpenos 1 e 2 apresentaram atividade citotóxica contra células 4T1 em baixa concentração.

Two new friedelane-type compounds 1 and 2 and five known pentacyclic triterpenes were isolated from branches of Maytenus robusta. Their structures were identified as 3,16-dioxo-29-hydroxyfriedelane (1), 3-oxo-16b,29-dihydroxyfriedelane (2), 3-oxofriedelane (3), 3b-friedelinol (4), 3,16-dioxofriedelane (5), 3-oxo-29-hydroxyfriedelane (6), and 3,16-dioxo-12a-hydroxyfriedelane (7). The structures and the stereochemistry of triterpenes 1 and 2 were established through infrared (IR), 1D/2D nuclear magnetic resonance (NMR), high-resolution atmospheric pressure chemical ionization mass spectrometry (HR-APCIMS) spectral data and powder X-ray diffraction. The in vitro cytotoxic property of triterpenes 1 to 6 on 4T1 murine breast cancer cells was evaluated. The triterpenes 1 and 2 showed cytotoxic activity against 4T1 cells at a lower concentration.

Friedelin molecular conformers were obtained by Density Functional Theory (DFT) and by ab initio structure determination from powder X-ray diffraction. Their conformers with the five rings in chair-chair-chair-boat-boat, and with all rings in chair, are energy degenerated in gas-phase according to DFT results. The powder diffraction data reveals that rings A, B and C of friedelin are in chair, and rings D and E in boat-boat, conformation. The high correlation values among powder diffraction data, DFT and reported single-crystal data indicate that the use of conventional X-ray diffractometer can be applied in routine laboratory analysis in the absence of a single-crystal diffractometer.

The chemical investigation of Salacia elliptica allowed to the isolation of 20 constituents: two polyols, one xanthone, a mixture of long chain hydrocarbons, one carboxylic acid, one polymer, two steroidal compounds, one aromatic ester and eleven pentacyclic triterpenes. These triterpenes include 3β-stearyloxy-oleanane, 3β-stearyloxy-ursane, one seco-friedelane, and eight compounds of the friedelane serie. The chemical structure and the relative configuration of a new triterpene 1,3-dioxo-16α-hydroxyfriedelane (15) were established through ¹H and 13C NMR including 2D experiments (HMBC, HMQC, COSY and NOESY) and herein reported for the first time.

The volatile oil from the leaves of E. urograndis was analyzed by GC and GC-MS. It was identified 10 compounds in which, orto-cimene (41.4%) and 1,8-cineol (25.8%) were the main constituents. The induction of deleterious effect to aquatic organisms due to the presence of volatile oil lixiviated from E. urograndis leaves was studied using Daphnia laevis and D. similis as bioindicators. Through the results of toxicological tests it was possible to show that the litterbag of E. urograndis represents a risk factor for the aquatic ecosystem of lakes and rivers that are in the surrounding area of large scale Eucalyptus plantations. The method can be used for monitor the quality of these types of aquatic environments.

The present paper describes the phytochemical investigation and biological activities of the chloroform, ethyl acetate and methanol extracts of leaf decocts of M. truncata Reiss (Celastraceae). Our studies afforded two flavonoid glycosides, quercetin-3-O-rhamnopyranosyl-O-glucopyranosyl- O-rhamnopyranosyl-O-galactopyranoside (1) and kampferol-3-O-rhamnopyranosyl-O-glucopyranosyl- O-rhamnopyranosyl-O-galactopyranoside (2) from the methanolic extract and dulcitol (3) from the ethyl acetate extract. Ethyl acetate and methanol extracts exhibited considerable antiulcerogenic and analgesic activities. The results of the phytochemical studies suggest that the healing activity of methanol extracts can be related to the presence of glycosyl flavonoids.

Foram testados quatro triterpenos pentacíclicos isolados de Austroplenckia populnea e quatro compostos de conhecida atividade anti-T. cruzi ou anti-malárica. Dos triterpenos testados 20alfa-hidroxi-tingenona mostrou atividade elevada, ácido epicatônico foi menos ativo, enquanto ácido populnílico e populnínico foram inativos contra o tripanossoma do subgênero Schizotrypanum testado. Benzonidazole, nifurtimox, cetoconazole e primaquina apresentaram efeito inibitório dose-dependente atingindo praticamente a inibição total do crescimento do parasita no final do tempo de incubação. O tripanossoma testado mostrou ser um modelo adequado para uma seleção preliminar de compostos anti. T. (S.) cruzi.

Four pentacyclic triterpenes isolated from Austroplenckia populnea and four compounds of known anti T. cruzi or anti-malarial activity were tested. Of those triterpenes tested 20alpha-hydroxy-tingenone showed high activity, epikatonic acid was less active, while populnilic and populninic acids were inactive against the trypanosome of the subgenus Schizotrypanum tested. Benzonidazole, nifurtimox, ketoconazole and primaquine presented a remarkable dose-dependent inhibitory effect reaching practically to a total growth inhibition of the parasite at the end of incubation time. The trypanosome tested appear to be a suitable model for preliminary screen for anti T. (S.) cruzi compounds.

Folhas de Austroplenckia populnea (mangabarana, marmelinho do campo) foram submetidos a estudo fitoquímico. Do extrato hexânico foram isolados e identificados três triterpenos pentacíclicos e um sesquiterpeno agarofurânico inédito. Realizou-se testes de atividade antiespermatogência utilizando parte deste extrato. Os resultados mostraram uma redução significativa do número de espermatozóides no epidídimo.

Um triterpeno lactônico inédito isolado do cerne de Austroplenckia populnea (Celastraceae) foi caracterizado como 3alfa-hidroxiolean-12-en-29,22alfa-olídeo (a gama-lactona do ácido 3alfa,22alfa-diidroxiolean-12-en-29alfa-óico), o epímero em C-3 da abruslactona A, com base em dados espectrais, oxidação e análise cristalográfica.

A new lactonic triterpene isolated from the heartwood of Austroplenckia populnea (Celastraceae) was characterized as 3alpha-hydroxyolean-12-en-29,22alpha-olide (the gamma-lactone of the 3alpha,22alpha-dihydroxyolean-12-en-29alpha-oic acid), the 3-epimer of the abruslactone A, on the basis of its spectral data, chemical transformations, and single crystal X-ray analysis.