Background: Co-inoculation of maize with Herbaspirillum seropedicae and humic substances increases the sizes of plant-associated bacterial populations and enhances grain yields under laboratory and field conditions. Root exudation is a key mechanism in the regulation of plant-bacterial interactions in the rhizosphere; humic matter supplementation is known to change the exudation of H + ions and organic acids from maize roots. Our starting premise was that H. seropedicae and humic acids would modify maize seedling exudation profiles. We postulated that a better understanding of these shifts in exudate profiles might be useful in improving the chemical environment to promote better performance of plant growth-promoting bacteria delivered as bioinoculants. Thus, root exudates of maize were collected and analyzed by gas chromatography-mass spectrometry (GC-MS) and proton nuclear magnetic resonance (

A investigação fitoquímica do extrato metanólico das folhas de Annona dioica (Annonaceae) resultou na identificação dos flavonóides kaempferol (1), 3-O-[3",6"-di-O-p-hidroxicinamoil]-β-galactopiranosil-kaempferol (2), 6"-O-p-hidroxicinamoil-β-galactopiranosil-kaempferol (3) e 3-O-β-galactopiranosil-kaempferol (4). As estruturas foram caracterizadas inequivocamente através de análises espectroscópicas utilizando-se RMN de C NMR spectroscopic analyses using 1D and 2D experiments. The cytotoxic effects of the flavonoids and flavonoid fraction (FF) were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay against Ehrlich carcinoma cells. The results indicated that 1, 2, 3 and FF exhibit significant antiproliferative action when compared to quercetin. The inhibitory action on DNA-topoisomerase I and II of all the flavonoids was evaluated by relaxation assays on pBR322 plasmid DNA. The results indicated the inhibitory and non-selective effects of the flavonoids on DNA-topoisomerase I and II.

This is the first phytochemical study of Eupatorium macrocephalum describing the isolation and identification of six triterpenes, one diterpene glycoside ester, six steroids, one flavonoid known as cirsilol, and six cinnamic acids derivatives. The structures of these known compounds were determined by spectral data analysis and comparison with literature values.

Abstract:The family Annonaceae, the largest family of the order Magnoliales, comprises about 130 genus and approximately 2300 species, distributed in the tropical and subtropical regions of Africa, Asia, Australia, Central and South America. In Brazil, this family is represented by approximately 27 genus and 290 species. Xylopia L. is one of the largest genus belonging to the Annonaceae family, comprising about 160 species, which are distributed mainly in the Brazilian cerrado. The main classes of secondary metabolites found in species of the genus Xylopia are alkaloids, flavonoids and diterpenes, the latter, in particular diterpenes trachylobanes, can be used as chemotaxonomic markers because in some species specificity. With purpose to contribute as a tool to the genus chemosystematics, this paper is a diterpenes review described in the literature, with a register of 73 substances since 1953, as well as the report of the biological activity potential performed by diterpenes of the genus Xylopia.Keywords: Xylopia; Diterpenes; Chemosystematic. ResumoA família Annonaceae, a maior família da ordem Magnoliales, compreende cerca de 130 gêneros e aproximadamente 2300 espécies, distribuídas nas regiões tropicais e subtropicais da África, Ásia, Austrália, América Central e do Sul. No Brasil, esta família é representada com aproximadamente 27 gêneros e 290 espécies. O gênero Xylopia L. é um dos maiores gêneros pertencente à família Annonaceae, compreendendo cerca de 160 espécies, que se distribuem principalmente em regiões de cerrado brasileiro. As principais classes de metabólitos secundários encontrados nas espécies do gênero Xylopia são os alcaloides, flavonoides e diterpenos, este último, em especial os diterpenos do tipo traquilobanos, podem ser utilizados como marcadores quimiotaxonômicos devido à especificidade em algumas espécies. Com o objetivo de contribuir para a quimiossistemática do gênero, o presente trabalho traz uma revisão dos diterpenos descritos na literatura, com o registro de 73 substâncias, a partir do ano de 1953, assim como o relato do potencial de atividade biológica desempenhado pelos diterpenos do gênero Xylopia.

The present study evaluated the relationship between herbivory and leaf quality of three abundant tree species (Cupania oblongifolia Mart., Siparuna guianensis Aubl. and Xylopia sericea St. Hill.) in the understory of a eucalyptus plantation and an adjacent Atlantic Rainforest fragment. Herbivory differed among species, since X. sericea was less attacked, while C. oblongifolia and S. guianensis were more. The species showed similar herbivory patterns between the investigated areas (eucalyptus plantation versus forest), although X. sericea showed higher herbivory rates in the forest fragment. Fiber values (NDF, CEL and LIG) varied significantly among the species, being lower in S. guianensis. X. sericea, the species with the highest C/N ratio, higher concentrations of total phenols, smaller leaf area and higher trichome density, showed the lowest leaf herbivory rates, corroborating the hypothesis that herbivory is lower in species with lower nutritional quality and a greater set of leaf defense features.