Publications by authors named "Milene M Praca-Fontes"

Article Synopsis
  • There is an increasing need for herbicides that are both effective and environmentally friendly, prompting a study on synthesizing new compounds from phenols and phenoxyacetic acid.
  • The research involved creating seven esters through a specific chemical reaction and characterizing them using advanced techniques, followed by testing their effects on seed germination and root development of two plant species.
  • Results indicated that some esters showed significant phytotoxic effects and caused noticeable damage at the cellular level in one of the plants, suggesting their potential use in developing new herbicides.
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The excessive use of herbicides has caused a series of problems related to human health, environmental pollution, and an increase in the resistance of plants to commercial herbicides. As an alternative, natural compounds and their semisynthetic derivatives have been widely studied to obtain environmentally friendly and more effective herbicides than the usual ones. In view of these factors, the aim of this work was to synthesize new molecules with herbicidal potential using thymol as a starting material, a natural phenol that has a pronounced phytotoxic effect.

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Article Synopsis
  • The use of synthetic herbicides in agriculture faces challenges due to health and environmental concerns, as well as increasing weed resistance.
  • Researchers synthesized glycerol-fluorinated triazole derivatives to evaluate their effectiveness in weed control, focusing on their potential low toxicity and efficiency.
  • Testing on Lactuca sativa showed varying levels of phytotoxic and cytogenotoxic effects, suggesting these compounds could serve as a new approach for weed management.
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Herbicides are commonly used to control weed. However, some plants are resistant to such products. To identify less harmful herbicides, it is crucial to search for different mechanisms of action.

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We investigated whether essential oil and aqueous and ethanolic extracts from M. vittoriana leaves have phytotoxic effects on the germination and initial development, and cytogenotoxic effects on the cell cycle, of model plants. The essential oil and extracts of M.

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Some forest trees have been polyploidized to improve their traits and to supply new germplasms for breeding programs. As trees have a long juvenile stage, the early characterization of the chromosome set doubling effects is crucial for previous selection. Thus, we aimed to characterize the chemical variability of essential oils from diploid and autotetraploid germplasms (autotetraploid A and B) of Eucalyptus benthamii, as well as to evaluate their larvicidal and allelopathic effects.

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Herbicides are agrochemicals applied in the control of weeds. With the frequent and repetitive use of these substances, serious problems have been reported. Compounds of natural origin and their derivatives are attractive options to obtain new compounds with herbicidal properties.

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Due to rising concerns for environmental and human health, many toxic compounds, such as auxin-based herbicides, have been tested in relation their toxicity effect. Especially cyto- and phytotoxic assays have been performed on a number monocot and eudicot plant species. In these approaches the toxicity level of the auxin is compared to a positive control - usually a commercial compound with known effects and chemical similarity to the target compound.

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The intensive application of agrochemicals in crops has negatively impacted the environment and other organisms. The use of naturally occurring compounds may be an alternative to mitigate these effects. Plants are secondary metabolite reservoirs and may present allelopathic activity, which is potentially interesting to be used in bioherbicide formulations.

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The use of allelopathic compounds is an alternative for weeds control, since they present low toxicity when compared with the synthetic herbicides, that may cause several damages, as the contamination of the environment. Our objective was to determine the chemical composition and allelopathic properties of the essential oils of Psidium cattleianum, P. myrtoides, P.

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On November 2015, one of Brazil's most important watersheds was impacted by the mine waste from Fundão dam collapse in Mariana. The mine waste traveled over 600 km along the Doce River before reaching the sea, causing severe devastation along its way. Here we assessed trace element concentrations and cytogenotoxic effects of the released mine waste.

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Chromosome morphometry and nuclear DNA content are useful data for cytotaxonomy and for understanding the evolutionary history of different taxa. However, the chromosome number is the only karyotype aspect reported for the species of Dorstenia so far. In this study, the nuclear genome size of Dorstenia arifolia (Lamarck, 1786), Dorstenia bonijesu (Carauta & C.

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Jatropha curcas L. (Euphorbiaceae) is important for biofuel production and as a feed ingredient for animal. However, the presence of phorbol esters in the oil and cake renders the seeds toxic.

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Image cytometry (ICM) has been used to measure DNA 2C-values by evaluating the optical density of Feulgen-stained nuclei. This optical measurement is carried out using three basic tools: microscopy, digital video camera, and image analysis software. Because ICM has been applied to plants, some authors have remarked that studies should be performed before this technique can be accepted as an accurate method for determination of plant genome size.

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Flow cytometry (FCM) techniques have enabled characterization of the genome size for various plant species. In order to measure the nuclear genome size of a species, reference standards with well-established DNA content are necessary. However, different 2C-values have been described for the same species used as reference standard.

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