The use of nano- and microparticles as a release system for agrochemicals has been increasing in agricultural sector. However, the production of eco-friendly and smart carriers that can be easily ...handled in the environment is still a challenge for this technology. In this context, we have developed a biodegradable release system for the herbicide atrazine with magnetic properties. Herein, we investigated the (a) physicochemical properties of the atrazine-loaded magnetic poly(ε-caprolactone) microparticles (MPs:ATZ), (b) in vitro release kinetic profile of the herbicide, and (c) phytotoxicity toward photosynthesis in the aquatic fern Azolla caroliniana. The encapsulation efficiency of the herbicide in the MPs:ATZ was ca. 69%, yielding spherical microparticles with a diameter of ca. 100 μm, a sustained-release profile, and easily manipulated with an external magnetic field. Also, phytotoxicity issues showed that the MPs:ATZ maintained their herbicidal activity via inhibition of PSII, showing lower toxicity compared with the nonencapsulated ATZ at 0.01 and 0.02 μmol·L–1. Therefore, this technology may conveniently promote a novel magnetic controlled release of the herbicide ATZ (with the potential to be collected from a watercourse) and act as a nutrient boost to the nontarget plant, with good herbicidal activity and reduced risk to the environment.
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•Biosynthesis of CuONPs was performed using yerba mate leaves extract.•CuONPs were characterized by SEM/EDS, AFM, FTIR, UV–vis and XRD.•Phytotoxicity of CuONPs was investigated by in ...vitro and in vivo using aquatic photoautotrophs.•Cyanobacterial phycocyanin (C-PC) and Lemna valdiviana were used as biological models.•CuONPs changed the optical behavior of C-PC and were toxic to Lemna valdiviana plants.
This work has assessed the impact of copper oxide nanoparticles (CuONPs), designed via green route, toward photosynthetic apparatus on aquatic photoautotrophic organisms. In order to filling knowledge gaps, in vitro and in vivo assays were performed, using cyanobacterial phycocyanin (C-PC) from Arthrospira platensis and Lemna valdiviana plants (duckweed), respectively. Impairment in light energy transfer became evident in C-PC exposed to CuONPs, giving rise to an increase of light absorption and a suppression of fluorescence emission. Fourier transform infrared spectroscopy (FTIR) results showed that C-PC structures might be altered by the nanoparticles, also revealed that CuONPs preferably interacts with -NH functional groups. The data also revealed that CuONPs affected the chlorophyll a content in duckweed leaves. In addition, photosystem II (PSII) performance was significantly affected by CuONPs, negatively impacting the PSII photochemical network. In summary, the results point out that, even eco-friendly designed, CuONPs may negatively affect the photosynthetic process when accumulated by aquatic photoautotrophs.
The use of nanotechnology has emerged in the agricultural sector. In recent years, several nano-enabled materials have been reported for weed control. Nano-enabled herbicides (also called ...nanoherbicides) can be designed from organic, inorganic, or hybrid materials. These materials have unique properties such as small size, specific surface area, and the ability to control the release of metal ions and organic molecules in the agricultural field. Some studies have reported the ability of nanoherbicides to provide better weed management compared to non-nanoformulations. However, studies regarding the environmental risk assessment and mechanisms of action of nanoherbicides in plants are still incipient. Nevertheless, they are essential to ensure a safe application for human health and the environment. In this review, we outlined the current understanding of nano-enabled herbicides as well as some strategic design to fabricate nanostructures for weed control. Also, a critical discussion regarding the fate, behavior and effects of nanoherbicides in plants was addressed in order to achieve products for environmentally friendly and sustainable agriculture.
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Despite the wide range of possible applications of nanopesticides, the mechanisms involved in their enhanced action remain largely unknown. Understanding the interaction between nanopesticides and ...plants is crucial for evaluating their potential safety application. Using an experimental and theoretical approach, this study aimed to investigate the target effect of paraquat-loaded chitosan/tripolyphosphate nanoparticles (
ca.
200 nm) on photosystem I (PSI). Electrochemical analysis showed distinct electroactivity behaviour between the encapsulated and non-encapsulated herbicide. The amount of lipid peroxidation, photooxidizable P700 reaction centre content, and NADPH/NADP
+
ratio levels were significantly decreased in spinach leaf tissue exposed to the nanoherbicide compared to those with the non-encapsulated herbicide. The data also revealed that the nanoformulation might promote oxidative stress based on changes observed in antioxidant enzymes. Also, molecular docking results showed a preferential disposition of the herbicide paraquat and paraquat-tripolyphosphate complex (TPP:PQ) in the ligand domain close to FAD and Glu312. Due to the inhibitor's strategic position in the catalytic pocket, a model of electron-capture is proposed, where the herbicide disturbs the redox process NADP
+
NADPH by capturing electrons to reduce itself. Finally, our findings provide important insights where the redox behaviour of paraquat may play a key role in the enhanced efficiency of nanoherbicides to the target binding site.
A paraquat-nanoherbicide presented distinct electroactivity behavior compared to its analytical counterpart, which may explain its greater herbicidal activity on plants.
Essential oils are natural products capable of being used as novel agrochemical products. In order to fill knowledge gaps, this work evaluates the bioherbicidal potential of Schinus terebinthifolia ...fruit essential oil (EOsST) emulsions on germination parameters of Lactuca sativa and Urochloa brizantha seeds. The hydrodynamic size distribution of the emulsions was evaluated by dynamic light scattering (DLS), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR). Also, the chemical composition of EOsST was performed by gas chromatography coupled to mass spectrometry (GC-MS). DLS results suggest nanoemulsion (NE) particle sizes smaller than 735 nm and SEM images showed spherical and cuboid shapes. FTIR spectra indicate peaks at 1640 cm−1 and 1440 cm−1, referring to the benzene ring, and the C–H stretching band from 2970 cm−1–2870 cm−1 indicates the interaction between EOsST and TX-100. GC-MS reveals that the major compounds present on EOsST were α-pinene, germacrene-D, and β-pinene. U. brizantha seed germination was reduced at doses >2 mg mL−1 and completely inhibited at 32 mg mL−1. For L. sativa there was a reduction in germination which was dose-dependent and no dose caused total inhibition. Moreover, a decrease in photosynthetic pigments, flavonoids, phenolics, and total tannins was observed. Enzyme activity was altered, with reduction to catalase and peroxidase.
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•Pre-emergent bioherbicidal activity of Schinus terebinthifolia Raddi essential oil was evaluated.•Morphophysiological damages were studied.•The photosynthetic pigments were strongly influenced by their presence in the nanoemulsion.•The enzymatic activity demonstrated the mode of action of the nanoemulsions.
•Particulate systems provide unique opportunities in agriculture.•Particles adhesion and uptake depend on their physicochemical features.•Targeting particles for plant nanobionics and pesticide ...delivery is discussed.•Stimuli responsive particulate systems are reviewed.•Past, present and future of agricultural technologies are put in perspective.
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The constantly increasing global food demand galvanizes innovative agricultural actions aimed to transcend current production levels. The predicted near-future food security scenario is alarming, requiring actions beyond traditional agricultural practices. Following the success of nanotechnologies in pharma and health sciences, nano-enabled agriculture is expected to increase crop yields and limit losses to pathogens, pests and other threats. Associated efforts are enabled by real-time sensing and controlled delivery, the latter of which considers cargos designed for controlled and targeted release, especially if triggered on demand. In this review, we introduce recent breakthroughs in these areas, including pesticide delivery as well as genetic modification and the engineering of nanoparticles for application in living materials. We offer a critical discussion on the physico-chemistry of adhesion of nanoparticles to vegetal tissue, their uptake and translocation in and within plants.
We sought to assess whether the effects of mesenchymal stromal cells (MSC) on lung inflammation and remodeling in experimental emphysema would differ according to MSC source and administration route. ...Emphysema was induced in C57BL/6 mice by intratracheal (IT) administration of porcine pancreatic elastase (0.1 UI) weekly for 1 month. After the last elastase instillation, saline or MSCs (1×105), isolated from either mouse bone marrow (BM), adipose tissue (AD) or lung tissue (L), were administered intravenously (IV) or IT. After 1 week, mice were euthanized. Regardless of administration route, MSCs from each source yielded: 1) decreased mean linear intercept, neutrophil infiltration, and cell apoptosis; 2) increased elastic fiber content; 3) reduced alveolar epithelial and endothelial cell damage; and 4) decreased keratinocyte-derived chemokine (KC, a mouse analog of interleukin-8) and transforming growth factor-β levels in lung tissue. In contrast with IV, IT MSC administration further reduced alveolar hyperinflation (BM-MSC) and collagen fiber content (BM-MSC and L-MSC). Intravenous administration of BM- and AD-MSCs reduced the number of M1 macrophages and pulmonary hypertension on echocardiography, while increasing vascular endothelial growth factor. Only BM-MSCs (IV > IT) increased the number of M2 macrophages. In conclusion, different MSC sources and administration routes variably reduced elastase-induced lung damage, but IV administration of BM-MSCs resulted in better cardiovascular function and change of the macrophage phenotype from M1 to M2.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Because the white matter of the cerebral cortex contains axons that connect distant neurons in the cortical gray matter, the relationship between the volumes of the 2 cortical compartments is key for ...information transmission in the brain. It has been suggested that the volume of the white matter scales universally as a function of the volume of the gray matter across mammalian species, as would be expected if a global principle of wiring minimization applied. Using a systematic analysis across several mammalian clades, here we show that the volume of the white matter does not scale universally with the volume of the gray matter across mammals and is not optimized for wiring minimization. Instead, the ratio between volumes of gray and white matter is universally predicted by the same equation that predicts the degree of folding of the cerebral cortex, given the clade-specific scaling of cortical thickness, such that the volume of the gray matter (or the ratio of gray to total cortical volumes) divided by the square root of cortical thickness is a universal function of total cortical volume, regardless of the number of cortical neurons. Thus, the very mechanism that we propose to generate cortical folding also results in compactness of the white matter to a predictable degree across a wide variety of mammalian species.
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