Two new bracelet cyclotides from roots of Pombalia calceolaria with potential anticancer activity have been characterized in this work. The cyclotides Poca A and B (1 and 2) and the previously known CyO4 (3) were de novo sequenced by MALDI-TOF/TOF mass spectrometry (MS). The MS2 spectra were examined and the amino acid sequences were determined. The purified peptides were tested for their cytotoxicity and effects on cell migration of MDA-MB-231, a triple-negative breast cancer cell line. The isolated cyclotides reduced the number of cancer cells by more than 80% at 20 μM, and the concentration-related cytotoxic responses were observed with IC50 values of 1.8, 2.7, and 9.8 μM for Poca A (1), Poca B (2), and CyO4 (3), respectively. Additionally, the inhibition of cell migration (wound-healing assay) exhibited that CyO4 (3) presents an interesting activity profile, in being able to inhibit cell migration (50%) at a subtoxic concentration (2 μM). The distribution of these cyclotides in the roots was analyzed by MALDI imaging, demonstrating that all three compounds are present in the phloem and cortical parenchyma regions.

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Species of Cannabaceae are wind pollinated, have inconspicuous and reduced flowers that are pistillate, staminate and apparently perfect on the same individual or on different individuals, with a single-whorled perianth and a pseudomonomerous gynoecium. Our objective is to understand the developmental processes that lead to such a reduced flower morphology and polygamy in Cannabis sativa, Celtis iguanaea and Trema micrantha. Floral buds and flowers were processed for surface, histological examinations and 3D reconstructions of vasculature. The single-whorled perianth is interpreted as a calyx because the organs are robust, have a broad base, an acute apex and quincuncial aestivation and are opposite the stamens. Petals are absent from inception. The dicliny is established at different development stages: stamens or carpels are absent from inception (Cannabis sativa), initiated and aborted during early (Trema micrantha, before sporo/gametogenesis) or late (Celtis iguanaea, after sporo/gametogenesis) development. Furthermore, in all species studied the carpels are congenitally united and the pseudomonomerous nature of the gynoecium is confirmed. Glandular trichomes are distributed on the bracts, sepals, anther connective and receptacle. Special floral features shared by species of Cannabaceae include precocious ovule development and sepals that are each vascularized by one bundle. The reduced flowers of Cannabaceae are the result of the absence from inception and/or abortion of organs and even of a whole whorl at different developmental stages, which were probably selected in response to pressures exerted by the similar pollination mechanism.

The goal of this study was to compare the vegetation structure of macrophytes in an anabranch-lake system. Sampling was carried out at flood in three types of aquatic vegetation, (wild-rice, floating meadow and Polygonum bank) in anabranch Bonfim (lotic) and in lake Mandioré (lentic) in plots along transects, to estimate the percent coverage and record life forms of species. We collected 59 species in 50 genera and 28 families. Fabaceae and Poaceae were the most representative and emergent plants predominated (62%). In the anabranch, with 48 species, Polygonum acuminatum and Paspalum repens (7%) were more frequent (8%); in the lake, with 39 species, the most frequent were Polygonum ferrugineum (7%) and Hymenachne amplexicaulis (9%). Both evaluated ecosystems have low floristic similarity (66.6%), which was repeated among the communities analyzed by environment: wild-rice (0.33%), Polygonum banks (0.37%); floating meadows (0.32%). The anabranch was richer and more diverse than the lake; wild-rice community was the most diverse compared to other ones in anabranch, while in the lake the Polygonum bank community was the most diverse. The life forms of species varied in relation to the environments (lotic and lentic) studied.

Premise of the Study This study details the unusual synorganization of the staminate flower in wind‐pollinated urticalean rosids to add the missing pieces that complete the puzzle of the explosive mechanism of pollen release in this group. Methods Flower buds and flowers were analyzed using light and scanning electron microscopy. Key Results The pistillode, stamens, and sepals form a floral apparatus that explosively releases pollen to be carried by the wind. The anthers dehisce when the stamens are still inflexed on the floral bud and are enveloped by the sepals and supported by an inflated pistillode. The distension of the filaments presses the pistillode, which decreases the pressure exerted on the anthers by releasing the air accumulated internally through its apical orifice. The extended filaments and the dehiscent free anthers move rapidly outward from the center of the flower. This movement of the filaments is then blocked by the robust basally united sepals, which causes a rapid inversion of the anther position, thus hurling the pollen grains far from the flower. The pollen grains are released grouped by the mucilage produced in high quantity in the cells found in all floral organs. Conclusions The anatomical structure of the pistillode and the finding of mucilaginous cells are the main features that help in the understanding the explosive mechanism of pollen release in urticalean rosids. The pistillode can be considered an exaptation because it was evolved later to provide a new role in the plant, optimizing male fitness.

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We present the leaf anatomy of seven amphibious species of Aeschynomene L. (Papilionoideae, Leguminosae), interpreting their structures and ecological functions, and also, providing information on which their taxonomy can be based, especially of morphologically similar species. We evaluated Aeschynomene americana, A. ciliata, A. evenia, A. denticulata, A. fluminensis, A. rudis and A. sensitiva. The anatomy corroborates the separation of the series Americanae, Fluminenses, Indicae and Sensitivae, with the shape of the petiole, types of trichomes and quantity of vascular units in the petiole as main characteristics to delimit the species. The petiole shape varies from cylindric in A. americana, A. sensitiva and A. fluminensis, to triangular in A. evenia and quadrangular in A. rudis, A. denticulata and A. ciliata. We observed four types of trichomes: hydathode trichome, long conic trichome, short conic trichome and bulb-based trichome. The hydathode trichome was the most common, except for A. americana and A. fluminensis. Species with higher affinity with water share similar adaptive characteristics, including hydathode trichomes described for the first time for the genus. This article adds unseen descriptions for the genus and on the adaptation factors of the amphibious species.Keywords: macrophytes, Fabaceae, hydathode trichome. Interpretações ecológicas da anatomia foliar de espécies anfíbias deAeschynomene L. (Leguminosae -Papilionoideae) ResumoNeste trabalho é apresentada a anatomia foliar de sete espécies anfíbias de Aeschynomene L., interpretando estruturas e suas funções ecológicas e fornecendo informações que subsidiam sua taxonomia, principalmente de espécies semelhantes morfologicamente. Foram avaliadas Aeschynomene americana, A. ciliata, A. evenia, A. denticulata, A. Palavras-chave: macrófitas, Fabaceae, tricoma-hidatódio.

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