Trypanocidal activity of 1,3,7-trihydroxy-2-(3-methylbut-2-enyl)-xanthone isolated from Kielmeyera coriacea.

This work evaluated the activity and ultrastructural and morphological alterations induced by the xanthone 1,3,7-trihydroxy-2-(3-methylbut-2-enyl)-xanthone (C23) isolated from Kielmeyera coriacea against Trypanosoma cruzi. This xanthone had inhibitory activity against the three forms of this protozoan and did not induce toxicity in mammalian cells. The best activity of this xanthone was against the intracellular amastigote form. Additionally, the mitochondrion was the main target of this compound, reflected by electronic microscopy and rhodamine 123 assays. Our MitoSOX assay results also indicated that C23 increased O2(-) production in mitochondrion. C23 might be a promising chemotherapeutic agent against T. cruzi because its trypanocidal action involves the disruption of mitochondrion, a specific target of Trypanosomatides.

Atribuição dos deslocamentos químicos dos átomos de ¹H e 13C do acetato de acantoaustralida / 1H and 13C NMR assignments of acanthoaustralide-1-O-Acetate

Do extrato hidroetanólico das partes aéreas de Acanthospermum australe (Asteraceae) foram identificados uma lactona diterpênica, o acetato de acantoaustralida (1) e dois flavonoides: quercetina (2) e crisosplenol D (3). As estruturas foram identificadas através de técnicas espectroscópicas de RMN de ¹H e 13C, gHSQC, gHMBC, TOCSY, gNOESY, EM e pela comparação com dados da literatura.

From the hydroethanolic extract of the aerial parts of Acanthospermum australe (Asteraceae) a diterpene lactone, acanthoaustralide-1-O-Acetate (1) and two flavonoids: quercetin (2) and chrysosplenol D (3) were identified. The structures were determined though the use of spectroscopic techniques such as NMR (¹H, 13C{¹H}, gHSQC, gHMBC, TOCSY, gNOESY), MS and compared with the literature data.

Estudo morfoanatômico preliminar do caule e da folha de Acanthospermum australe (Loefl.) Kuntze (Asteraceae-Heliantheae) / A preliminary morphological and anatomical study of the stem and leaf of Acanthospermum australe (Loefl.) Kuntze (Asteraceae-Heliantheae)

Descrições morfoanatômicas preliminares do caule e da folha de Acanthospermum australe (Loefl.) Kuntze foram realizadas a partir de material vegetal fresco e fixado. Secções transversais e paradérmicas, coradas com safranina/azul de astra e azul de toluidina foram analisadas ao microscópio. As superfícies do caule e da folha foram observadas através de microscopia eletrônica de varredura. A. australe apresenta, tanto no caule quanto na folha, tricomas tectores pluricelulares, unisseriados e de extremidades afiladas, e glandulares discóides, com pedúnculo curto unicelular, no qual se prendem cinco séries de células. A folha é anfiestomática e os estômatos são do tipo anomocítico, levemente proeminentes em relação ao nível das demais células epidérmicas. O caule apresenta crescimento secundário inicial, destacando-se os ductos secretores no parênquima cortical e medular.

Preliminary morphological and anatomical descriptions of stem and leaf of Acanthospermum australe (Loefl.) Kuntze were made in fresh and fixed material. Cross and superficial sections, stained with safranin/astra blue and Toluidine blue were analyzed at the light microscopic and the images were acquired by means the program Image Pro-Plus, version 4.0 (Media Cybertecnics). The surface of the stem and leaf were observed through scanning electronic microscopy. The species presents in the stem and leaf surface multicellular nonglandular trichome, uniseriate with a pointed edge and multicellular glandular trichome like a disk with a unicellular peduncle, in which is attached a series of five cells. The leaf presents anomocytic stomata in both surfaces a little prominent in relation to the level of the epidermal cells. The stem presents an initial secondary growth with evident secretory ducts in the cortex and pith.

Acylperoxylated and seco-mexicanolides from stems of Khaya anthotheca.

The stems of Khaya anthotheca yielded two new limonoids, which were identified on the basis of spectroscopic analysis as 1alpha,8alpha-oxido-3beta-acetoxy-2alpha-acylperoxy-1alpha,14alpha-dihydroxy-[3.3.1(10,2)]-bicyclomeliac-7,19-olide (3) and 3-acetoxy-8,14-dien-8,30-seco-khayalactone (4). Methyl 1alpha,2beta,3alpha,6,8alpha,14beta-hexahydroxy-[4.2.1(10,30).1(1,4)]-tricyclomeliac-7-oate, scopoletin, and 3-O-beta-D-glucopyranosylsitosterol were also isolated. The limonoids were of little value to clarify the basis of the nonresistance against Hypsipyla grandella.