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The wide use of nanoparticles (NPs), gives concern about their possible negative implications in the environment and living organisms. In particular, titanium dioxide (TiO2) NPs are accumulated in biosolids (Bs) coming from wastewater treatment plants, which in turn are used as farm soil amendments and are becoming an important way of NPs entrance in the terrestrial ecosystems. In this study, to simulate a low and cumulative load of TiO2 NPs, 80 and 800 mg TiO2per Kg of soil were spiked in the Bs prior to its addition to soil. The effects of different crystal phases of TiO2 NPs (pure anatase and pure rutile or their mixture) and their non-coated bulk counterparts (larger particles) on the availability of mineral nutrients and on the status of the bacterial communities together with the nutritional status of Pisum sativum L. plants were evaluated. Results showed the reduction, to different extents, on the availability of important soil mineral nutrients (e.g. Mn 65%, Fe 20%, P 27%, averagely), in some cases size- (e.g. P) and dose-dependent. Bacterial biodiversity was also affected by the presence of high TiO2 dose in soil. The mineral nutrition of pea plants was also altered, showing the main reduction in Mn (80% in the roots and 50% in the shoots), K, Zn, P (respectively, 80, 40, and 35% in the roots), and an increase of N in the shoots, with possible consequences on the quality of the crop. The present study gives new integrated data on the effects of TiO2 NPs in the soil-plant system, on the soil health and on the nutritional quality of crops, rising new implications for future policies and human health.
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Biossólidos , Nanopartículas/química , Pisum sativum/metabolismo , Poluentes do Solo/análise , Titânio/química , Produtos Agrícolas , Ecossistema , Humanos , Nutrientes , Estado Nutricional , Raízes de Plantas/efeitos dos fármacos , Solo/químicaRESUMO
BACKGROUND: Consumer preference today is for the consumption of functional food and the reduction of chemical preservatives. Moreover, the antimicrobial properties and health-promoting qualities of plant secondary metabolites are well known. Due to forecasted climate changes and increasing human population, agricultural practices for saving water have become a concern. In the present study, the physiological responses of curly kale Brassica oleracea L. convar. Acephala (DC) var. sabellica to drought stress and the impact of water limitation on the concentration of selected secondary metabolites were investigated under laboratory-controlled conditions. RESULTS: Results indicated that drought stress increased the content of trans-2-hexenal, phytol and δ-tocopherol, and decreased chlorophyll content. Moreover, drought stress increased antioxidant capacity and the expression of AOP2, a gene associated with the biosynthesis of aliphatic alkenyl glucosinolates, and of three genes - TGG1, TGGE and PEN2 - encoding for myrosinases, the enzymes involved in glucosinolate breakdown. CONCLUSION: The present study shows that water limitation during the growing phase might be exploited as a sustainable practice for producing curly kale with a high concentration of nutritionally important health-promoting bioactive metabolites. © 2019 Society of Chemical Industry.
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Brassica/química , Brassica/metabolismo , Metabolismo Secundário , Antioxidantes/análise , Antioxidantes/metabolismo , Secas , Glucosinolatos/análise , Glucosinolatos/metabolismoRESUMO
The yeast Pichia fermentans DISAABA 726 strain (P. fermentans) is a dimorphic yeast that under different environmental conditions may switch from a yeast-like to pseudohyphal morphology. We hypothesize that exosomes-like vesicles (EV) could mediate this rapid modification. EV are membrane-derived vesicles carrying lipids, proteins, mRNAs and microRNAs and have been recognized as important mediators of intercellular communication. Although it has been assumed for a long time that fungi release EV, knowledge of their functions is still limited. In this work we analyze P. fermentans EV production during growth in two different media containing urea (YCU) or methionine (YCM) where yeast-like or pseudohyphal morphology are produced. We developed a procedure to extract EV from the neighboring biofilm which is faster and more efficient as compared to the widely used ultracentrifugation method. Differences in morphology and RNA content of EV suggest that they might have an active role during dimorphic transition as response to the growth conditions. Our findings are coherent with a general state of hypoxic stress of the pseudohyphal cells.
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Biofilmes , Vesículas Extracelulares/metabolismo , Pichia/fisiologia , Meios de Cultura , Vesículas Extracelulares/ultraestrutura , Proteínas Fúngicas/metabolismo , MicroRNAs/metabolismo , Viabilidade Microbiana , Pichia/citologia , Pichia/ultraestrutura , RNA Fúngico/metabolismoRESUMO
MAIN CONCLUSION: The link HaWUS/ HaL1L , the opposite transcriptional behavior, and the decrease/increase in positive histone marks bond to both genes suggest an inhibitory effect of WUS on HaL1L in sunflower zygotic embryos. In Arabidopsis, a group of transcription factors implicated in the earliest events of embryogenesis is the WUSCHEL-RELATED HOMEOBOX (WOX) protein family including WUSCHEL (WUS) and other 14 WOX protein, some of which contain a conserved WUS-box domain in addition to the homeodomain. WUS transcripts appear very early in embryogenesis, at the 16-cell embryo stage, but gradually become restricted to the center of the developing shoot apical meristem (SAM) primordium and continues to be expressed in cells of the niche/organizing center of SAM and floral meristems to maintain stem cell population. Moreover, WUS has decisive roles in the embryonic program presumably promoting the vegetative-to-embryonic transition and/or maintaining the identity of the embryonic stem cells. However, data on the direct interaction between WUS and key genes for seed development (as LEC1 and L1L) are not collected. The novelty of this report consists in the characterization of Helianthus annuus WUS (HaWUS) gene and in its analysis regarding the pattern of the methylated lysine 4 (K4) of the Histone H3 and of the acetylated histone H3 during the zygotic embryo development. Also, a parallel investigation was performed for HaL1L gene since two copies of the WUS-binding site (WUSATA), previously identified on HaL1L nucleotide sequence, were able to be bound by the HaWUS recombinant protein suggesting a not described effect of HaWUS on HaL1L transcription.
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Helianthus/genética , Código das Histonas/genética , Proteínas de Plantas/genética , Sequência de Bases , Fator de Ligação a CCAAT/genética , Fator de Ligação a CCAAT/metabolismo , Regulação da Expressão Gênica de Plantas , Helianthus/citologia , Helianthus/embriologia , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/metabolismo , Estrutura Terciária de Proteína , Proteínas Recombinantes , Análise de Sequência de DNA , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
The Pichia fermentans strain DISAABA 726 is a biofilm-forming yeast that has been proposed as biocontrol agent to control brown rot on apple. How ever, when inoculated on peach, strain 726 shows yeast-like to pseudohyphal transition coupled to a pathogenic behaviour. To identify the proteins potentially involved in such transition process, a comparative proteome analysis of P. fermentans 726 developed on peach (filamentous growth) vs apple (yeast-like growth) was carried out using two-dimensional gel electrophoresis coupled with mass spectrometry analysis. The proteome comparison was also performed between the two different cell morphologies induced in a liquid medium amended with urea (yeast-like cells) or methionine (filamentous cells) to exclude fruit tissue impact on the transition. Seventy-three protein spots showed significant variations in abundance (±twofold, p < 0.01, confidence intervals 99 %) between pseudohyphal vs yeast-like morphology produced on fruits. Among them, 30 proteins changed their levels when the two morphologies were developed in liquid medium. The identified proteins belong to several pathways and functions, such as glycolysis, amino acid synthesis, chaperones, and signalling transduction. The possible role of a group of proteins belonging to the carbohydrate pathway in the metabolic re-organisation during P. fermentans dimorphic transition is discussed.
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Biofilmes/crescimento & desenvolvimento , Proteínas Fúngicas/biossíntese , Hifas/metabolismo , Pichia/fisiologia , Proteoma/biossínteseRESUMO
BACKGROUND: The effects of white wheat bread and white wheat bread added with a bioactive compound mixture (Cyclanthera pedata, Glycine max, Monascus-fermented red mold rice, Cynara scolymus and Medicago sativa) were examined on hypercholesterolemic and steatotic mice, divided into four groups: control diet (CTR), high-fat diet (HFD), high-fat diet with white wheat bread added with 1.5 g kg(-1) of mixture (HFD+AB) and high-fat diet with white wheat bread (HFD+B). RESULTS: Total serum cholesterol in the HFD+AB and HFD+B groups and hepatic triglycerides in the HFD+AB group decreased compared with the HFD group. Liver histology confirmed lower lipid drop accumulation in the HFD+AB group than in the HFD and HFD+B groups. HFD+AB caused a 7.0-fold increase and a 3.5-fold reduction in CYP7A1 and SREBP-1c gene expression respectively compared with the HFD group. Moreover, the HFD+B group showed a 2.2-, 8.4- and 1.5-fold increase in HMG CoA reductase, CYP7A1 and LDLr gene expression respectively compared with the HFD group. CONCLUSION: Both the white wheat bread and the added white wheat bread induced cholesterol reduction by increasing CYP7A1. Moreover, the added white wheat bread improved steatosis by decreasing SREBP-1c gene expression.
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Dieta Hiperlipídica , Carboidratos da Dieta/administração & dosagem , Fígado Gorduroso/dietoterapia , Hipercolesterolemia/dietoterapia , Hipolipemiantes/administração & dosagem , Animais , Pão , Colesterol/sangue , Fibras na Dieta/administração & dosagem , Modelos Animais de Doenças , Fígado Gorduroso/sangue , Hipercolesterolemia/sangue , Metabolismo dos Lipídeos , Camundongos , Camundongos Endogâmicos C57BL , Monascus , Triglicerídeos/sangueRESUMO
AIMS/HYPOTHESIS: Cardiac steatosis and myocardial insulin resistance elevate the risk of cardiac complications in obesity and diabetes. We aimed to disentangle the effects of circulating glucose, insulin and NEFA on myocardial triacylglycerol (TG) content and myocardial glucose uptake. METHODS: Twenty-two pigs were stratified according to four protocols: low NEFA + low insulin (nicotinic acid), high NEFA + low insulin (fasting) and high insulin + low NEFA ± high glucose (hyperinsulinaemia-hyperglycaemia or hyperinsulinaemia-euglycaemia). Positron emission tomography, [U-(13)C]palmitate enrichment techniques and tissue biopsies were used to assess myocardial metabolism. Heart rate and rate-pressure product (RPP) were monitored. RESULTS: Myocardial glucose extraction was increased by NEFA suppression and was similar in the hyperinsulinaemia-hypergylcaemia, hyperinsulinaemia-euglycaemia and nicotinic acid groups. Hyperglycaemia enhanced myocardial glucose uptake due to a mass action. Myocardial TG content was greatest in the fasting group, whereas hyperinsulinaemia had a mild effect. Heart rate and RPP increased in hyperinsulinaemia-euglycaemia, in which cardiac glycogen content was reduced. Heart rate correlated with myocardial TG and glycogen content. CONCLUSIONS/INTERPRETATION: Elevated NEFA levels represent a powerful, self-sufficient promoter of cardiac TG accumulation and are a downregulator of myocardial glucose uptake, indicating that the focus of treatment should be to 'normalise' adipose tissue function to lower the risk of cardiac TG accumulation and myocardial insulin resistance. The observation that hyperinsulinaemia and nicotinic acid led to myocardial fuel deprivation provides a potential explanation for the cardiovascular outcomes reported in recent intensive glucose-lowering and NEFA-lowering clinical trials.
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Glicemia/metabolismo , Ácidos Graxos não Esterificados/sangue , Resistência à Insulina/fisiologia , Miocárdio/metabolismo , Triglicerídeos/metabolismo , Animais , Insulina , SuínosRESUMO
Copper bromide (CuBr2) effects on seed germination and plantlet development of Vicia sativa L. are evaluated through mitotic index, chromosome aberrations, nucleolar activity and mineral profile. CuBr2 induces a significant presence of micronuclei, sticky and c-metaphases, anaphase bridges and chromosome breaks. Increased number of nucleoli and scattering of AgNOR proteins from the nucleolus in the nuclear surface at CuBr2 1mM and in the cytoplasm at CuBr2 5mM, goes along with the decrease of root growth. In V. sativa embryo the content of many macro and micronutrients increases up to copper 1mM in agreement with reserve mobilization while at CuBr2 5mM some elements are present in lower amount. We hypothesize that inhibitory effects observed at 5mM are due either to a nutrient shortage or to a direct influence of copper on root cell division, evidenced by low mitotic index, high occurrence of chromosome aberrations and loss of material from the nucleolus.
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Brometos/toxicidade , Cobre/toxicidade , Germinação/efeitos dos fármacos , Mitose/efeitos dos fármacos , Vicia sativa/efeitos dos fármacos , Aberrações Cromossômicas , Dano ao DNA , Minerais/análise , Índice Mitótico , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Vicia sativa/química , Vicia sativa/crescimento & desenvolvimentoRESUMO
Polystyrene nanoplastics and titanium dioxide nanoparticles are widely spread in all environments, often coexisting within identical frameworks. Both these contaminants can induce negative effects on cell and plant physiology, giving concerns on their possible interaction which could increase each other's harmful effects on plants. Despite the urgency of this issue, there is very little literature addressing it. To evaluate the potential risk of this co-contamination, lentil seeds were treated for five days with polystyrene nanoplastics and titanium dioxide nanoparticles (anatase crystalline form), alone and in co-presence. Cytological analyses, and histochemical and biochemical evaluation of oxidative stress were carried out on isolated shoots and roots. TEM analysis seemed to indicate the absence of physical/chemical interactions between the two nanomaterials. Seedlings under cotreatment showed the greatest cytotoxic and genotoxic effects and high levels of oxidative stress markers associated with growth inhibition. Even if biochemical data did not evidence significant differences between materials treated with polystyrene nanoplastics alone or in co-presence with titanium dioxide nanoparticles, histochemical analysis highlighted a different pattern of oxidative markers, suggesting a synergistic effect by the two nanomaterials. In accordance, the fluorescence signal linked to nanoplastics in root and shoot was higher under cotreatment, perhaps due to the well-known ability of titanium dioxide nanoparticles to induce root tissue damage, in this way facilitating the uptake and translocation of polystyrene nanoplastics into the plant body. In the antioxidant machinery, peroxidase activity showed a significant increase in treated roots, in particular under cotreatment, probably more associated with stress-induced lignin synthesis than with hydrogen peroxide detoxification. Present results clearly indicate the worsening by metal nanoparticles of the negative effects of nanoplastics on plants, underlining the importance of research considering the impact of cotreatments with different nanomaterials, which may better reflect the complex environmental conditions.
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Halophyte species represent valuable reservoirs of natural antioxidants, and, among these, Salicornia europaea stands out as a promising edible plant. In this study, young and old S. europaea leaves were compared for the content of bioactive compounds and antioxidant activity to assess changes in different growth phases; then, the potential protective effects against low-dose CCl4-induced toxicant-associated fatty liver disease (TAFLD) were investigated by administering an aqueous suspension of young leaves to rats daily for two weeks. Quantification of total and individual phenolic compounds and in vitro antioxidant activity assays (DPPH, FRAP, and ORAC) showed the highest values in young leaves compared to mature ones. Salicornia treatment mitigated CCl4-induced hepatic oxidative stress, reducing lipid peroxidation and protein carbonyl levels, and preserving the decrease in glutathione levels. Electronic paramagnetic resonance (EPR) spectroscopy confirmed these results in the liver and evidenced free radicals increase prevention in the brain. Salicornia treatment also attenuated enzymatic disruptions in the liver's drug metabolizing system and Nrf2-dependent antioxidant enzymes. Furthermore, histopathological examination revealed reduced hepatic lipid accumulation and inflammation. Overall, this study highlights Salicornia's potential as a source of bioactive compounds with effective hepatoprotective properties capable to prevent TAFLD.
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Quinoa (Chenopodium quinoa Willd.) is a plant of South American origin recently valorized for its nutritional and nutraceutical properties in human diet. Quinoa is cultivated in many parts of the world, with a selection of varieties with good adaptability to extreme climatic conditions and salt stress. The variety Red Faro, native to southern Chile but harvested in Tunisia, was considered for salt stress resistance, considering its seed germination and 10-day seedling growth at increasing doses of NaCl (0, 100, 200 and 300 mM). Seedlings were spectrophotometrically analyzed for antioxidant secondary metabolites (polyphenols, flavonoids, flavonols and anthocyanins), antioxidant capacity (ORAC, oxygen radical absorbance capacity, DPPH*, 2,2-diphenyl-1-pic-rylhydrazyl), antioxidant enzyme activity (superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX) and catalase (CAT)) and mineral nutrient content in root and shoot tissues. Cytogenetic analysis of root tip was performed to check for meristematic activity and the possible presence of chromosomal abnormalities induced by salt stress. The results indicated a general increase in antioxidant molecules and antioxidant enzymes NaCl dose-dependent, no effects on seed germination but negative effects on seedling growth, and little effect on root meristems mitotic activity. These results indicated that stress conditions can induce an increase in biologically active molecules that could be used for nutraceutical purposes.
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Agroecosystems represent more and more a huge long-term sink for plastic compounds which inevitably undergo fragmentation, generating micro- and nano-plastics, with potential adverse effects on soil chemistry and living organisms. The present work was focused on the short-term effects of two different concentrations of polystyrene nanoplastics (PSNPs) (0.1 or 1 g L-1 suspensions) on rice seedlings starting from seed germination, hypothesizing that possible acute effects on seedlings could depend on oxidative damage trigged by PSNPs internalization. As shown by TEM analysis, PSNPs were absorbed by roots and translocated to the shoots, affected root cell ultrastructure, the germination process, seedling growth and root mitotic activity, inducing cytogenetic aberration. Treatments were not correlated with increase in oxidative stress markers, but rather with a different pattern of their localization both in roots and in shoots, impairing H2O2 homeostasis and membrane damage, despite the adequate antioxidant response recorded. The harmful effects of PSNPs on cell biology and physiology of rice seedlings could be caused not only by a direct action by the PSNPs but also by changes in the production/diffusion of ROS at the tissue/cellular level.
Assuntos
Oryza , Plântula , Germinação , Peróxido de Hidrogênio , Microplásticos , Raízes de Plantas , Poliestirenos , SementesRESUMO
Microplastics (MPs) and nanoplastics (NPs) are ubiquitous in natural habitats and the risks their presence poses to marine environments and organisms are of increasing concern. There is evidence that seagrass meadows are particularly prone to accumulate plastic debris, including polystyrene particles, but the impacts of this pollutant on seagrass performance are currently unknown. This is a relevant knowledge gap as seagrasses provide multiple ecosystem services and are declining globally due to anthropogenic impact and climate-change-related stressors. Here, we explored the potential effects of a 12 day-exposure of seagrasses to one concentration (68 µg/L) of polystyrene MPs and NPs on the growth, oxidative status, and photosynthetic efficiency of plants using the foundation species Cymodocea nodosa as a model. Among plant organs, adventitious roots were particularly affected by MPs and NPs showing complete degeneration. The number of leaves per shoot was lower in MPs- and NPs-treated plants compared to control plants, and leaf loss exceeded new leaf production in MPs-treated plants. MPs also reduced photochemical efficiency and increased pigment content compared to control plants. Shoots of NPs-treated plants showed a greater oxidative damage and phenol content than those of control plants and MPs-treated plants. Biochemical data about oxidative stress markers were consistent with histochemical results. The effects of MPs on C. nodosa could be related to their adhesion to plant surface while those of NPs to entering tissues. Our study provides the first experimental evidence of the potential harmful effects of MPs/NPs on seagrass development. It also suggests that the exposure of seagrasses to MPs/NPs in natural environments could have negative consequences on the functioning of seagrass ecosystems. This stresses the importance of implementing cleaning programs to remove all plastics already present in marine habitats as well as of undertaking specific actions to prevent the introduction of these pollutants within seagrass meadows.
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Alismatales , Poluentes Ambientais , Alismatales/química , Ecossistema , Microplásticos , Plásticos , PoliestirenosRESUMO
Phytoremediation represents a natural method to remove contaminants from soil. The goal of this study was to investigate the potential of phosphate-assisted phytoremediation by two energy crops, Cannabis sativa L. and Brassica juncea L., for the sustainable remediation of heavily arsenic-contaminated industrial soil. The two species were investigated for uptake, translocation, and physiological effects of arsenic and phosphate in a microcosm test. Although C. sativa and B. juncea were symptomless when grown in arsenic-contaminated soil, an important reduction of biomass (50 and 25%, respectively) was observed as a stress marker. Phytotoxicity and cytotoxicity effects promoted by contaminated soils were investigated in both the species and a model plant for ecotoxicity studies, Vicia faba L., which is the most developed model to test genotoxicity effects in terms of chromosomal aberration and micronuclei presence. The higher amount of arsenic was found in C. sativa and B. juncea roots (on average 1473 and 778 mg kg-1, respectively), but both species were able to uptake and translocate arsenic in leaves and stems, up to 47.0 and 189 mg kg-1, respectively. Phosphate treatment had no effect on arsenic uptake in none of the crop, but significantly improved the plant performance. Biomass production resulted similar to that of B. juncea control plants. Antioxidant enzymatic activities and photosynthetic performance responded differently in the two crops. The present investigation provides new insight for a proficient selection of the most suitable crop species for sustainable phytomanagement of a highly polluted As-contaminated site by coupled phytoremediation-bioenergy approach.
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Arsênio , Cannabis , Poluentes do Solo , Biodegradação Ambiental , Mostardeira , Solo , Poluentes do Solo/análiseRESUMO
In order to investigate the biological hazard of effluents from textile industries of Fez-Boulmane region in Morocco, mutagenicity and phytotoxicity tests were performed on different biological systems. Moreover, the efficiency of a Sequencing Batch Reactor (SBR) system, working by activated sludge on a laboratory scale, was estimated by comparing the ecotoxicity results observed before and after wastewater treatment. Evaluation of the genotoxic potential was investigated by means of classic mutagenicity tests on D7 strain of Saccharomyces cerevisiae and by phytotoxicity tests on Allium sativum L., Vicia faba L. and Lactuca sativa L., estimating micronuclei presence, mitotic index and cytogenetic anomalies. The results obtained by testing untreated wastewater demonstrated major genotoxicity effects in S. cerevisiae and various levels of phytotoxicity in the three plant systems, while after SBR treatment no more ecotoxicological consequences were observed. These data confirm the effectiveness of the SBR system in removing toxic substances from textile wastewaters in Fez-Boulmane region.
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Monitoramento Ambiental/métodos , Resíduos Industriais/efeitos adversos , Mutagênicos/toxicidade , Indústria Têxtil , Poluentes Químicos da Água/toxicidade , Ecotoxicologia , Resíduos Industriais/estatística & dados numéricos , Marrocos , Testes de MutagenicidadeRESUMO
Biosolids (Bs) for use in agriculture are an important way for introducing and transferring TiO2 nanoparticles (NPs) to plants and food chain. Roots of Pisum sativum L. plants grown in Bs-amended soils spiked with TiO2 800 mg/kg as rutile NPs, anatase NPs, mixture of both NPs and submicron particles (SMPs) were investigated by Transmission Electron Microscopy (TEM), synchrotron radiation based micro X-ray Fluorescence and micro X-ray Absorption Near-Edge Structure (µXRF/µXANES) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). TEM analysis showed damages in cells ultrastructure of all treated samples, although a more evident effect was observed with single anatase or rutile NPs treatments. Micro-XRF and TEM evidenced the presence of nano and SMPs mainly in the cortex cells near the rhizodermis. Micro-XRF/micro-XANES analysis revealed anatase, rutile, and ilmenite as the main TiO2 polymorphs in the original soil and Bs, and the preferential anatase uptake by the roots. For all treatments Ti concentration in the roots increased by 38-56%, however plants translocation factor (TF) increased mostly with NPs treatment (261-315%) and less with SMPs (about 85%), with respect to control. In addition, all samples showed a limited transfer of TiO2 to the shoots (very low TF value). These findings evidenced a potential toxicity of TiO2 NPs present in Bs and accumulating in soil, suggesting the necessity of appropriate regulations for the occurrence of NPs in Bs used in agriculture.
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In the analysis by electrospray (+) of an extract of hemp sprouts put in a polypropylene vial, we found a large contamination of a plastic additive. It was characterized by multiple-stage MSn experiments (MS ÷ MS10 ) and identified as tris(2,4-di-tert-butylphenyl)phosphate, also known with the synonyms F32IRS6B46, oxidized Naugard 524, and others. The MS2 ÷ MS7 spectra are characterized by consecutive eliminations of six isobutene molecules from the tert-butyl moieties, some of them also occurring in the ion source. The first three are calculated to occur preferentially from the ortho positions, whereas eliminations from the para positions are estimated to be less favored at about 5-6 kcal/mol in each step. Once the first three isobutene molecules are eliminated, the remaining three are lost from the tert-butyl moieties in para positions (MS5 ÷ MS7 ), yielding protonated triphenylphosphate, whose structure has been confirmed by the MS2 spectrum of triphenylphosphate standard: the latter spectrum is almost superimposable with the MS8 spectrum of the analyte under investigation. MS8 and MS9 spectra show main losses of water and C6 H4 molecules. The MS10 spectrum of precursor ions at m/z 215 shows the gas-phase addition of water and methanol and ions at m/z 168, attributable to the loss of a phosphorus oxide radical. Density functional theory (DFT) calculations (Becke 3LYP [B3LYP] 6-311+G(2d,2p)) have been used to evaluate structure and stability of different ionic and neutral species involved in the decomposition pathways and to calculate thermochemical data of the decomposition reactions. This multistep mass analysis combined with theoretical calculations resulted to be particularly useful and effective, yielding chemical, thermochemical, and mechanistic data of significant utility in the structural characterization and identification of the unknown analyte as well as to define its gas-phase reactivity under a multistep low-energy collision-induced dissociation regime.
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E171 (titanium dioxide, TiO2), an authorized foods and beverage additive, is also used in food packaging and in pharmaceutical and cosmetic preparations. E171 is considered to be an inert and non-digestible material, not storable in animal tissues, but the possible presence of TiO2 nanoparticles (NP) may present a risk to human health and the environment. We determined the presence of 15% TiO2 NP in a commercial E171 food additive product, by electron microscopy. The biological effects of E171 were assessed in Lens culinaris and Allium cepa for the following endpoints: percentage of germination, root elongation, mitotic index, presence of chromosomal abnormalities, and micronuclei. The results indicated low phytotoxicity but dose-dependent genotoxicity. We also observed internalization of TiO2 NP and ultrastructural alterations in the root systems.
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Aditivos Alimentares/toxicidade , Lens (Planta)/efeitos dos fármacos , Mutagênicos/toxicidade , Nanopartículas/toxicidade , Cebolas/efeitos dos fármacos , Titânio/toxicidade , Animais , Aberrações Cromossômicas/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Germinação/efeitos dos fármacos , Humanos , Lens (Planta)/metabolismo , Lens (Planta)/ultraestrutura , Micronúcleos com Defeito Cromossômico , Microscopia Eletrônica , Índice Mitótico/estatística & dados numéricos , Cebolas/metabolismo , Cebolas/ultraestrutura , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/ultraestruturaRESUMO
With the aim to investigate the mechanisms of action of nano plastics (nano PS) on plants, seeds of Allium cepa were germinated for 72 h in the presence of polystyrene nano PS (50 nm size, at concentrations of 0.01, 0.1 and 1 g L-1) and, subsequently, roots were analysed by a multifaceted approach. No effect was induced by any concentration of nano PS on the percentage of seed germination while root growth was inhibited by 0.1 and 1 g L-1 nano PS. Cytological analysis of the root meristems indicated cytotoxicity (reduction of mitotic index) and genotoxicity (induction of cytogenetic anomalies and micronuclei) starting from the lowest dose. Moreover, the biochemical and histochemical analysis of oxidative stress markers gave evidence of stress induction, especially at the highest doses. Damages reported could be due to mechanical surface contact in root external layers, as evidenced by histological localization, and to the internalization of nano PS in different cellular compartments, observed under TEM. The present research underlines the hazardous nature of nano PS, that for their ability to be internalized into crop plants, can enter into different trophic levels of the food chain.
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Allium , Germinação , Cebolas , Estresse Oxidativo , Raízes de Plantas , Plásticos , Poliestirenos , Germinação/efeitos dos fármacos , Índice Mitótico , Cebolas/efeitos dos fármacos , Cebolas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plásticos/metabolismo , Plásticos/toxicidade , Poliestirenos/metabolismo , Poliestirenos/toxicidadeRESUMO
Lisosan® Reduction is a plant mixture produced from powder of fermented Triticum aestivum (Lisosan® G), Desmodium adscendens, Malus domestica, Picrorhiza kurroa and Hordeum vulgare. The aim of this study was to characterise the phenolic profile of Lisosan® Reduction and to evaluate the effects of aqueous extract on mice fed a high fat diet (HFD). Syringic acid, trans sinapic acid and neochlorogenic acid were identified by HPLC-DAD to be the dominant polyphenols of Lisosan® Reduction, followed by vitexin, trans p-coumeric acid and trans ferulic acid. Mice treated with aqueous extract of Lisosan® Reduction (60 mg/kg b.w.) showed a significant decrease of serum cholesterol, glucose and triglycerides level and a significant increase of CYP7A1 gene expression, compared to HFD group.