34 research outputs found

    Hydroalcoholic extracts of Vellozia squamata: study of its nanoemulsions for pharmaceutical or cosmetic applications

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    AbstractSome species of plants are notable for the wide range of biologically active constituents in their tissues. Chemical and pharmacological studies of Vellozia squamata Pohl, Velloziaceae, popularly known in Brasil as “canela-de-ema” are scarce, but showed the presence of di-and triterpenoid that may be of scientii c interest. In the present study the hydroalcoholic extracts from leafs and stems of V. squamata were submitted to phytochemical prospection to identify the principal groups of constituents, and the antioxidant activity was determined by DPPH method. The hydroethanolic extracts presented higher antioxidant activity. Thus, nanoemulsion formulations were prepared using the method of phase inversion. Accelerated stability tests, such as heat stress and centrifugation were made, and physical and chemical properties of the nanoemulsions were established. Stable formulations were obtained from both extracts from leafs and stems. By the results was possible to establish the potential application of hydroalcoholic extracts from V. squamata in development of products with antioxidant properties and demonstrate a promising pharmaceutical produc

    SAMARAS OF AUSTROPLENCKIA POPULNEA (CELASTRACEAE): NEW CONSTITUENTS AND EFFECT OF EXTRACTS AND FRIEDELIN ON GERMINATION OF BIDENS PILOSA (ASTERACEAE)

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    Objective: Evaluation of the impact of extracts and constituents from samaras of Austroplenckia populnea on percentage of seed germination (%SG), germination speed index (GSI), length of rootlets (LR), seedling length (SL), and on dry mass (DM) of Bidens pilosa L weed.Methods: The  powder  of  samaras  was  extracted  with  organic  solvents  providing  the  hexane  (SAPEH),  chloroform  (SAPEC),  ethyl  acetate  (SAPEAE) and ethanol  (SAPEE)  extracts. The terpene 1 was isolated from SAPEH by means of column and thin layer chromatography and identified through NMR spectroscopy. Each extract and 1 were subjected to growth inhibition assays evaluating the following parameters: %SG, GSI, LR, SL and DM, with five repetitions.Results: The compounds Friedelin (1), 7-hydroxy-clerodan-3-en-16,15:18,20-diolide (2), 3,5,7,4'-tetrahydroxy-6-methoxy-8-prenylflavanone (3), tetradecanamide (4), and 4-hydroxy-1,6,15-acetyloxy-8,9-benzoyloxy-agarofurane (5) were isolated from hexane extract of samaras of A. populnea and identified by spectroscopic data. The compounds 2, 3 and 5 were not previously described as being chemical constituents from Celastraceae family. In addition, the novel compounds 3 and 5 were described here for the first time. Substantial effect on the germination of B. pilosa L. (picão-preto) was observed after treatment of seeds with nonpolar extracts from Samaras of A. populnea. Friedelin inhibited the seed germination in the tested concentrations showing toxic properties against picão-preto.Conclusion: The germination inhibition of seeds was higher using nonpolar extracts than polar extract. Friedelin inhibited the seed germination in the tested concentrations showing toxic properties against B. pilosa.Â

    CYTOTOXICITY, ANTI-POLIOVIRUS ACTIVITY AND IN SILICO BIOLOGICAL EVALUATION OF CONSTITUENTS FROM MAYTENUS GONOCLADA (CELASTRACEAE)

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    Objective: The in silico free access web tools PASS online and ChemMapper were used to predict potential biological activities of compounds 1 to 8 isolated from Maytenus gonoclada (Celastraceae). The constituents 4'-O-methylepigalocatequin (6), tingenone (7) and proanthocyanidin A (8), and ethanolic extracts were subjected to in vitro cytotoxicity using VERO cells and anti-Poliovirus assays. Methods: QSAR and molecular superposition, correlating the average number of pharmacophores were used in the prediction studies. Cellular line VERO ATCC CCL-81 was used to determine anti-Poliovirus effect, observed by colorimetric (MTT) method. The annexing V/propidium iodide assay was used to determine the occurrence of apoptosis in the cytotoxicity assays. Results: The experimental results found for constituents 6-8 were in accordance with observed data obtained through PASS online and ChemMapper simulation. Conclusion: Compound 7 showed higher cytotoxic and apoptosis induction properties, and 6 and 8 presented anti-Poliovirus activity

    Chemical constituents and allelopathic activity of the essential oil from leaves of Eremanthus erythropappus.

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    The essential oil from leaves of Eremanthus erythropappus (DC.) MacLeish (Asteraceae) collected in South-eastern Brazil was extracted using a combination of water and steam distillation and investigated by chromatography/mass spectrometry (GC-MS). The sesquiterpene hydrocarbons were predominant (46.6%), followed by oxygenated sesquiterpenes (29.3%) and monoterpene hydrocarbons (18.8%). The major compounds were (?)-caryophyllene (29.3%), caryophyllene oxide (22.1%) and ?-pinene (12.8%). The allelopathic activity of E. erythropappus essential oil on the seed germination and radicle length of seedlings was evaluated in lettuce (Lactuca sativa L.), tomato (Lycopersicum esculentum Mill.) and in two field weeds (field mustard ? Brassica rapa L. and hairy beggarticks ? Bidens pilosa L.). Among the weed species tested, the most significant inhibition of seed germination was observed in field mustard, as measured by the half?minimal inhibitory concentration, IC50 (IC50?=?26.5??L mL?1), and the most significant inhibitory effect on radicle length of seedlings was observed in seedlings of hairy beggarticks (IC50?=?16.3??L mL?1). In contrast, the lowest allelopathic effects of E. erythropappus essential oil on seed germination and radicle length of seedlings were observed in tomato (IC50?=?>200??L mL?1 and 130.1??L mL?1 respectively) and lettuce (IC50?=?97.1??L mL?1 and 35.1??L mL?1 respectively). These results revealed significant allelopathic potential of E. erythropappus essential oil against weeds, but minimal effect on lettuce and tomato germination, and thus suggests it is feasible to use E. erythropappus sustainability as an eco-friendly bioherbicide in cropping settings

    Spatial variability of physical and chemical attributes of some forest soils in southeastern of Brazil

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    Capão Bonito forest soils, São Paulo state, Brazil, have been used for forestry purposes for almost one century. Detailed knowledge about the distribution of soil attributes over the landscape is of fundamental importance for proper management of natural resources. The purpose of this study was to identify the variability and spatial dependence of chemical and physical attributes of Capão Bonito forest soils. A large soil database of regional land was raised and organized. Most of the selected variables were close to the lognormal frequency range. Soil texture presented a higher range in the A horizon, and the nugget effect and sill were greater in the B horizon. These differences are attributed to the parent material of the region (Itararé Geologic Formation), which presents uneven distribution of sediments. Chemical attributes related to soil fertility presented a higher spatial dependence range in the B horizon, probably as a result of more intensive management and erosion history of the superficial soil layer. Maps for some attributes were interpolated. These had specific areas of occurrence and a wide distribution along the perimeter of the Capão Bonito District Forest, allowing a future site-specific soil management

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
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