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1.
Bull Environ Contam Toxicol ; 105(1): 127-133, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32548730

RESUMO

In this work the toxicity caused by explosive industries effluent (yellow water) at different levels of toxicity (genetic, cellular and organismal level) was evaluated by the Allium cepa test and the Sorghum sudanense germination. The results showed that the effluent paralyze the mitotic process, keeping the cells in the interphase, decreasing the mitotic index in A. cepa. Chromosomal abnormalities such as c-metaphases, adhesions, breaks, early ascending chromosomes and irregular nucleus were observed for this receptor species. The germination of S. sudanense was reduced, and the development of the radicles were affected, showing reduced tolerance index at the highest concentrations of the effluent. Thus, it is concluded that the effluent from the explosive industry is extremely toxic to the tested organisms, both in cellular and chromosomal level and also for seed germination.


Assuntos
Substâncias Explosivas/toxicidade , Germinação/efeitos dos fármacos , Cebolas/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Aberrações Cromossômicas , Índice Mitótico , Cebolas/genética , Cebolas/fisiologia , Sorghum
2.
Pestic Biochem Physiol ; 165: 104553, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359535

RESUMO

Thrips tabaci is a key pest of onions, especially in the Pacific Northwestern USA. Management of T. tabaci is dominated by the application of various insecticides. However, T. tabaci is known to develop insecticide resistance which possibly leads to control failures, crop loss, and environmental concern. Here, we evaluated resistance status of T. tabaci populations from conventional and organic commercial onion fields to three widely used insecticides: oxamyl, methomyl, and abamectin with on-field concentration-mortality bioassays. The biochemistry and molecular mechanisms underlying resistance to these insecticides were also investigated by using enzymatic assays and detecting resistance-associated mutations. Field-evolved resistance to oxamyl, methomyl and abamectin were detected in most of the T. tabaci populations collected from conventional onion farms. At the labeled field rate, all the tested insecticides, particularly methomyl and oxamyl, had significantly reduced efficacy. Enzymatic assays of insecticide target and detoxification enzymes indicated that T. tabaci populations in Western USA onions harbor multiple mechanisms of resistance including enhanced activities of detoxification enzymes and target site insensitivity. Our results provide new information in understanding the dynamics of T. tabaci adaptation to multiple insecticides, which will help to design sustainable insecticide resistance management strategies for T. tabaci. Furthermore, this study provides the foundation for future research in identifying the biochemical and molecular markers associated with insecticide resistance in T. tabaci.


Assuntos
Inseticidas , Tisanópteros , Animais , Resistência a Inseticidas , Metomil , Cebolas
3.
Environ Sci Pollut Res Int ; 27(22): 28066-28076, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32405953

RESUMO

Effects of imidacloprid and iprodione, isolated and in mixture, were assessed by using seed germination and root growth test, flow cytometry, and chromosomal aberrations test on Allium cepa root meristem. The highest concentrations of imidacloprid, including field concentration, increased the frequency of sub-G1 particles, decreased the frequency of nuclei in G2/M, increased the coefficient of variation of G1 (CVG1) and the frequency of aberrant cells, and inhibited the mitotic index culminating in the reduction in root length. All doses of iprodione also presented cytogenotoxic action. The highest concentration of the fungicide affected the growth of A. cepa roots. In response to exposure to pesticide mixtures, the cell cycle of A. cepa was blocked in the G1 phase. The mixtures with low doses of the pesticides significantly decreased the mitotic index, and as a consequence, the genotoxicity was reduced. In the mixtures with the highest doses of the agrochemicals, the blockage of the cell cycle was insufficient for damage repair, resulting in a significant increase of chromosomal aberrations. The results suggest caution in the use of pesticides doses that induce cytological abnormalities in non-target organisms.


Assuntos
Cebolas , Praguicidas , Aminoimidazol Carboxamida/análogos & derivados , Aberrações Cromossômicas , Dano ao DNA , Humanos , Hidantoínas , Meristema , Índice Mitótico , Neonicotinoides , Nitrocompostos , Raízes de Plantas
4.
PLoS One ; 15(5): e0231753, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32369481

RESUMO

Lou onion (Allium fistulosum L. var. viviparum) is an abundant source of flavonols which provides additional health benefits to diseases. Genome-wide specific length amplified fragment (SLAF) sequencing method is a rapidly developed deep sequencing technologies used for selection and identification of genetic loci or markers. This study aimed to elucidate the genetic diversity of 122 onion accessions in China using the SLAF-seq method. A set of 122 onion accessions including 107 A.fistulosum L. var. viviparum Makino, 3 A.fistulosum L. var. gigantum Makino, 3 A.mongolicum Regel and 9 A.cepa L. accessions (3 whites, 3 reds and 3 yellows) from different regions in China were enrolled. Genomic DNA was isolated from young leaves and prepared for the SLAF-seq, which generated a total of 1,387.55 M reads and 162,321 high quality SNPs (integrity >0.5 and MAF >0.05). These SNPs were used for the construction of neighbor-joining phylogenetic tree, in which 10 A.fistulosum L. var. viviparum Makino accessions from Yinchuan (Ningxia province) and Datong (Qinghai province) had close genetic relationship. The 3 A.cepa L. clusters (red, white and yellow) had close genetic relationship especially with the 97 A.fistulosum L. var. viviparum Makino accessions. Population structure analysis suggested entire population could be clustered into 3 groups, while principal component analysis (PCA) showed there were 4 genetic groups. We confirmed the SLAF-seq approach was effective in genetic diversity analysis in red onion accessions. The key findings would provide a reference to the Lou onion germplasm in China.


Assuntos
Cebolas/genética , Polimorfismo de Nucleotídeo Único , Sequenciamento Completo do Genoma/métodos , China , Mapeamento Cromossômico , Genética Populacional , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Folhas de Planta/genética , Análise de Componente Principal , Locos de Características Quantitativas
5.
Environ Monit Assess ; 192(6): 360, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32399591

RESUMO

Hospital laundries are responsible for a significant part of the amount of wastewater that is generated in hospitals. Hospital laundry wastewater represents a complex mixture of chemicals that arouse concerns about possible environmental risks. The objective of the present study was to evaluate the cytotoxicity of different laundry effluents from the Regional University Hospital of Maringá, Paraná, Brazil, on Allium cepa L. meristematic root cells. The effluents were characterised as rinsing, wetting, prewashing, washing, softening, wastewater (the effluent generated at the end of the washing process), the wastewater that was treated by physicochemical (PC) processes and the wastewater that was treated by advanced oxidation processes (PC + UV, PC + H2O2 and PC + UV/H2O2). The mitotic indexes were calculated by scoring 5000 cells per group and the statistical analyses were performed by one-way ANOVA, followed by Tukey's post-test (α = 0.05). Results showed that the rinsing, wetting, prewashing and wastewater laundry effluents were cytotoxic at 24 h of exposure, significantly reducing the mitotic index. Despite the slight cytotoxicity of the PC + UV/H2O2 treatment, physicochemical and advanced oxidation processes efficiently reduced the critical parameters of wastewater, such as the biochemical and chemical oxygen demands, to tolerable levels of effluent discharge. It is essential to perform constant monitoring of these effluents in order to reduce the possible occurrence of environmental impacts.


Assuntos
Cebolas , Poluentes Químicos da Água , Brasil , Monitoramento Ambiental , Hospitais , Peróxido de Hidrogênio , Oxirredução , Águas Residuárias
6.
Chemosphere ; 256: 126985, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32445994

RESUMO

Biodegradable mulch films are an alternative to polyethylene films used in agriculture for weed control, improving crop productivity. This change could minimize the residue production and costs related to the final disposal. Nevertheless, the environmental safety of these biodegradable products is scarcely investigated. In this work, samples of poly(butylene adipate-co-terephthalate)-PBAT mulch films, with and without UV stabilizer additives, were prepared. Aqueous extracts of soil samples, where mulch films were disposed, were investigated using bioassays with Lactuca sativa, Allium cepa, and cell culture HepG2/C3A. As PBAT is expected to suffer photodegradation and biodegradation, soil samples mixed with films before and after these processes were evaluated. Soil aqueous extracts promoted root grown (mainly hypocotyl) of L. sativa, probably due to presence of nutrients. So, to evaluate toxicity potential, in this case it was necessary to use aqueous extract prepared with soil instead of ultrapure water as the control. After doing this analysis it was observed that no adverse impacts due to PBAT films occurred. No chromosomal abnormalities were observed in A. cepa bioassay for any of tested samples. The absence of genotoxic potential was confirmed by comet assay and micronucleus test using human hepatocarcinoma cell line HepG2/C3A. These results showed that the soil did not induce damage to the tested organisms, before and after degradation of PBAT films.


Assuntos
Biodegradação Ambiental , Alface/efeitos dos fármacos , Cebolas/efeitos dos fármacos , Adipatos , Agricultura , Alcenos , Ecotoxicologia , Humanos , Alface/fisiologia , Cebolas/fisiologia , Ácidos Ftálicos , Poliésteres/química , Poluentes do Solo
7.
PLoS One ; 15(4): e0231082, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240261

RESUMO

Increased periods of prolonged droughts followed by severe precipitation events are expected throughout South America due to climate change. Freshwater sediments are especially sensitive to these changing climate conditions. The increased oscillation of water levels in aquatic ecosystems causes enhanced cycles of sediment drying and rewetting. Here we experimentally evaluate the effects of induced drought followed by a rewetting event on the release of carbon dioxide (CO2), methane (CH4), nutrients (nitrogen and phosphorus), and trace elements (iron, manganese, and zinc) from the sediment of a tropical reservoir in southeastern Brazil. Furthermore, we used bulb onions (Allium cepa) to assess the potential cytogenotoxicity of the water overlying sediments after rewetting. We found peaks in CO2 and CH4 emissions when sediments first transitioned from wet to dry, with fluxes declining as sediments dried out. CO2 emissions peaked again upon rewetting, whereas CH4 emissions remained unaltered. Our experiment also revealed average increases by up to a factor of ~5000 in the release rates of nutrients and trace elements in water overlying sediments after rewetting. These increased release rates of potentially toxic compounds likely explain the lower replication of Allium cepa cells (up to 22% reduction) exposed to water overlying sediments after rewetting. Our findings suggest that increased events of drought followed by rewetting may lead to a range of changes in freshwater ecosystems, including nutrient enrichment, increased toxicity following resuspension of contaminants, and higher emission of greenhouse gases to the atmosphere.


Assuntos
Dessecação , Sedimentos Geológicos/química , Gases de Efeito Estufa/análise , Mutagênicos/toxicidade , Oligoelementos/análise , Água/química , Dióxido de Carbono/análise , Morte Celular/efeitos dos fármacos , Difusão , Metano/análise , Índice Mitótico , Nitrogênio/análise , Cebolas/citologia , Fósforo/análise
8.
Environ Sci Pollut Res Int ; 27(16): 20335-20343, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32242316

RESUMO

Imazalil (IMZ), a fungicide containing imidazole group, is extensively used for the prevention and treatment of fungal diseases in plants. Current study was performed to examine cyto-genotoxic potential of IMZ on Allium cepa roots by following Allium ana-telophase and single cell gel electrophoresis (comet) assays. The concentration which reduced the growth of the root tips of IMZ by 50% compared to the negative control group (EC50) was found to be 1 µg/mL by Allium root growth inhibition test. 0.5, 1, and 2 µg/mL concentrations of IMZ were exposed to Allium roots for intervals of 24, 48, 72, and 96 h. 10 µg/mL of methyl methane sulfonate (MMS) and distilled water were used as control groups, both positive and negative. Statistical analysis was performed by using one-way ANOVA with Duncan's multiple comparison tests at p ≤ 0.05 and Pearson correlation test at p = 0.01. IMZ showed cytotoxic effect by statistically decreasing root growth and mitotic index (MI) and also genotoxic effect by statistically increasing chromosomal aberrations (CAs) and DNA damage compared to the negative control group. With these cyto-genotoxic effects, it should be used carefully and further cyto-genotoxic mechanisms should be investigated along with other toxicity tests.


Assuntos
Fungicidas Industriais/farmacologia , Cebolas/genética , Aberrações Cromossômicas , Análise Citogenética , Dano ao DNA , Humanos , Imidazóis/farmacologia , Meristema/efeitos dos fármacos , Índice Mitótico , Raízes de Plantas/efeitos dos fármacos
9.
Int J Syst Evol Microbiol ; 70(5): 3018-3026, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32228807

RESUMO

Five Gram-reaction-negative, aerobic, motile with one to three polar flagella, rod-shaped bacterial strains, MAFF 212408T, MAFF 212409, MAFF 212410, MAFF 301498 and MAFF 730085, were isolated from diseased Welsh onion (Allium fistulosum L.) in Japan. Analysis of their 16S rRNA gene sequences showed that they belong to the genus Pseudomonas with the highest similarity to Pseudomonas extremaustralis 14-3T (99.86 %), Pseudomonas antarctica CMS 35T (99.79 %) and Pseudomonas poae DSM 14936T (99.72%). The genomic DNA G+C content was 59.5 mol% and the major fatty acids (>5 %) were summed feature 3, C16 : 0, summed feature 8 and C12 : 0 2-OH. Multilocus sequence analysis using the rpoD, gyrB and rpoB gene sequences and phylogenomic analysis based on the 90 core genes demonstrated that the strains are members of the P. fluorescens subgroup, but are distant from all closely related species. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) analysis confirmed low genomic relatedness to their closest relatives [below the recommended thresholds of 95 % (ANI) and 70 % (dDDH) for prokaryotic species delineation]. The strains were characterized by using API 20NE and Biolog GEN III tests, and inoculation tests in Welsh onion, showing that they are phenotypically differentiated from their closest relatives. Based on the genetic and phenotypic evidence, the strains should be classified as representing a novel species, for which the name Pseudomonas kitaguniensis sp. nov. is proposed. The type strain is MAFF 212408T (=ICMP 23530T).


Assuntos
Cebolas/microbiologia , Filogenia , Doenças das Plantas/microbiologia , Pseudomonas/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Japão , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Pseudomonas/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
Sci Total Environ ; 725: 138387, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32298898

RESUMO

With the exponential growth of nanomaterial production in the last years, nano copper (Cu)-based compounds are gaining more consideration in agriculture since they can work as pesticides or fertilizers. Chinese scallions (Allium fistulosum), which are characterized by their high content of the antioxidant allicin, were the chosen plants for this study. Spectroscopic and microscopic techniques were used to evaluate the nutrient element, allicin content, and enzyme antioxidant properties of scallion plants. Plants were harvested after growing for 80 days at greenhouse conditions in soil amended with CuO particles [nano (nCuO) and bulk (bCuO)] and CuSO4 at 75-600 mg/kg]. Two-photon microscopy images demonstrated the particulate Cu uptake in nCuO and bCuO treated roots. In plants exposed to 150 mg/kg of the Cu-based compounds, root Cu content was higher in plants treated with nCuO compared with bCuO, CuSO4, and control (p ≤ 0.05). At 150 mg/kg, nCuO increased root Ca (86%), root Fe (71%), bulb Ca (74%), and bulb Mg (108%) content, compared with control (p ≤ 0.05). At the same concentration, bCuO reduced root Ca (67%) and root Mg (33%), compared with control (p ≤ 0.05). At all concentrations, nCuO and CuSO4 increased leaf allicin (56-187% and 42-90%, respectively), compared with control (p ≤ 0.05). The antioxidant enzymes were differentially affected by the Cu-based treatments. Overall, the data showed that nCuO enhances nutrient and allicin contents in scallion, which suggests they might be used as a nanofertilizer for onion production.


Assuntos
Allium , Nanopartículas Metálicas , Nanopartículas , Cobre , Nutrientes , Cebolas , Raízes de Plantas , Ácidos Sulfínicos
11.
Chemosphere ; 253: 126675, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32278918

RESUMO

The carbamazepine (CBZ) is one of the most frequently detected anticonvulsant drugs in water bodies. Although there are reports of its ecotoxicological effects in the scientific literature, toxicity studies have not focused on establishing the mechanism by which CBZ produces its effect at environmentally relevant concentrations. The objective of this work was to evaluate cyto-genotoxicity and its relationship with oxidative stress produced by carbamazepine in the Allium cepa model. The cytotoxicity and genotoxicity, as well as the biomarkers of oxidative stress were analyzed in the roots of A. cepa, exposed to 1 and 31.36 µg L-1 after 2, 6, 12, 24, 48 and 72 h. The results show that genotoxic capacity of this drug in the roots of A. cepa is related to the generation of oxidative stress, in particular with production of hydroperoxides and oxidized proteins. Also, the cytotoxic effect has a high correlation with DNA damage. The results of the present study clearly indicate that bioassays with sensitive plants such as A. cepa are useful and complementary tools to evaluate the environmental impact of emerging contaminants.


Assuntos
Carbamazepina/toxicidade , Poluentes Ambientais/toxicidade , Cebolas/fisiologia , Allium , Bioensaio , Dano ao DNA , Biomarcadores Ambientais , Cebolas/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Raízes de Plantas/efeitos dos fármacos
12.
Chemosphere ; 254: 126716, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32334246

RESUMO

Cyanobacteria are prokaryotes involved in the contamination of aquatic environments since they release toxins that are highly potent and dangerous for living organisms. Prokaryotes produce endo and exotoxins, among others. Exotoxins are highly toxic, while endotoxins have milder toxic effects. The present study evaluated the cytotoxicogenetic potency of both toxins studying them in different concentrations of cyanobacterial biomasses (1 µg/L, 1.5 µg/L, 2 µg/L), to assess the amount of exotoxin present in the cultured medium in which the cyanobacteria were grown. For this evaluation, we used an extract taken from the medium in a concentration of 10%. Our results showed that genotoxic and mutagenic changes in Allium cepa could be observed in all of the varying concentrations of biomass (endotoxin action) and also in the medium induced with exotoxin. Even at low concentrations, these toxins were highly effective at triggering changes in the DNA molecules of organisms exposed to them. This information is highly significant when considering environmental contamination caused by cyanobacteria blooms, since the results of this study show that these toxins may not only kill organisms when found in high concentrations, but also induce mutations when found in low concentrations. Since these mutations are expressed later on in the organisms, it is impossible to associate the observed effect with the event that induced the damage.


Assuntos
Cianobactérias/patogenicidade , Dano ao DNA , Endotoxinas/toxicidade , Exotoxinas/toxicidade , Biomassa , Microcistinas/toxicidade , Mutagênicos/toxicidade , Cebolas/efeitos dos fármacos
13.
Environ Sci Pollut Res Int ; 27(14): 17382-17392, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32157539

RESUMO

In this study, the hyperthermophilic dark fermentation of onion wastes (OW) for hydrogen production was investigated. OW were used at different proportions in mixed fruit and vegetable wastes (FVW) to evaluate their effect on hydrogen production by Thermotoga maritima. Fermentations were performed in a pH-controlled batch stirred tank reactor (BSTR) using seawater as a simplified reaction medium. Results showed that increasing OW proportions in total fruit and vegetable wastes (tFVW) improved H2 production. Therefore, increasing the OW to tFVW ratio from 0 to 0.8 increased the cumulative H2 production from 109 to 223.6 mmol/L. The H2 productivity was also improved from 7.3 to 28.82 mmol/h.L. In fact, OW contain carbohydrates, sulfur compounds, and other nutrients, which were used as a carbon source and energetic substrate for H2 production by the halophilic bacterium T. maritima in seawater without additional chemical compounds. Then, a H2 yield of 3.36 mol H2/mol hexose was achieved using 200 mL of OW, containing 55 mmol/L of carbohydrates. A concept of H2 production from FVW at high proportions of OW in a simplified reaction medium was proposed. It allowed a H2 yield of 209 LH2/kg volatile solids which could be an interesting future alternative to the current fossil fuel.


Assuntos
Carbono , Cebolas , Reatores Biológicos , Fermentação , Hidrogênio , Enxofre
14.
PLoS One ; 15(3): e0228485, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130211

RESUMO

Fifty four Trichoderma strains were isolated from soil samples collected from garlic and onion crops in eight different sites in Brazil and were identified using phylogenetic analysis based on combined ITS region, tef1-α, cal, act and rpb2 sequences. The genetic variability of the recovered Trichoderma species was analysed by AFLP and their phenotypic variability determined using MALDI-TOF. The strain clusters from both typing techniques coincided with the taxonomic determinations made from phylogenetic analysis. The phylogenetic analysis showed the occurrence of Trichoderma asperellum, Trichoderma asperelloides, Trichoderma afroharzianum, Trichoderma hamatum, Trichoderma lentiforme, Trichoderma koningiopsis, Trichoderma longibrachiatum and Trichoderma erinaceum, in the soil samples. We also identified and describe two new Trichoderma species, both in the harzianum clade of section Pachybasium, which we have named Trichoderma azevedoi sp. nov. and Trichoderma peberdyi sp. nov. The examined strains of both T. azevedoi (three strains) and T. peberdyi (12 strains) display significant genotypic and phenotypic variability, but form monophyletic clades with strong bootstrap and posterior probability support and are morphologically distinct from their respective most closely related species.


Assuntos
Alho/microbiologia , Cebolas/microbiologia , Microbiologia do Solo , Trichoderma/classificação , Trichoderma/isolamento & purificação , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Biodiversidade , Brasil , DNA Fúngico/análise , DNA Fúngico/genética , Técnicas de Tipagem Micológica/métodos , Filogenia , Análise de Sequência de DNA/métodos , Especificidade da Espécie , Trichoderma/citologia , Trichoderma/genética
15.
Food Chem ; 319: 126562, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32155536

RESUMO

This study investigated the effects of the addition of onion waste fractions into gluten-free (GF) bread to promote its health benefits. 5% of the control (C) GF flour blend was replaced with three waste fractions in the form of: fried onion (FO), dried onion (DO) and onion peel (OP). Antioxidant activity, content of flavonols and total polyphenols of breads increased in the following order: C < FO < DO < OP. No differences were observed in sensory analysis. We found that quercetin glycosides, dimers and trimer in OP-bread, determined according to their mass spectra, decomposed during baking and released free quercetin, which points to their thermal instability. Cross-over study revealed that consumption of OP-bread significantly increased (p < 0.05) antioxidant activity of consumers' blood compared to control bread consumption, indicating good bioavailability of flavonols. Results suggest incorporation of OP into GF bread can increase its biological value with satisfactory sensory acceptance.


Assuntos
Pão/análise , Cebolas/química , Cebolas/metabolismo , Disponibilidade Biológica , Culinária , Estudos Cross-Over , Polifenóis/química , Polifenóis/metabolismo , Quercetina/química , Quercetina/metabolismo , Rutina/química , Rutina/metabolismo
16.
Chemosphere ; 249: 126193, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32086064

RESUMO

Propanil can produce methemoglobinemia, hemolytic anemia, hepatotoxicity, metabolic disorder and nephrotoxicity. It also has a genotoxic effect, although it is not listed as a carcinogen and it continues to be applied excessively throughout the world. Consequently, in this study the cytogenotoxic effect of propanil was evaluated, using apical root cells of Allium cepa and Lens culinaris. In which, L. culinaris seeds and A. cepa bulbs were subjected to 6 treatments with propanil (2, 4, 6, 8, 10 and 12 mg L-1) and to distilled water as control treatment. Subsequently, the root growth was measured every 24 h for 3 days. Next, the mitotic index and cellular anomalies were determined. Whereby, decreased root development was observed in all treatments. Likewise, greater inhibition of mitosis was evidenced in L. culinaris compared to A. cepa. In addition, chromosomal abnormalities, such as nucleus absence, sticky chromosomes in metaphase and binucleated cells, were present in most of the treatments. Thus, the presence of micronuclei and the results of L. culinaris, indicate the high cytogenotoxicity of propanil and the feasibility of this species as bioindicator.


Assuntos
Herbicidas/toxicidade , Lens (Planta)/efeitos dos fármacos , Cebolas/efeitos dos fármacos , Propanil/toxicidade , Allium , Núcleo Celular , Aberrações Cromossômicas , Dano ao DNA , Biomarcadores Ambientais , Mitose , Índice Mitótico , Raízes de Plantas/efeitos dos fármacos , Testes de Toxicidade
17.
Ecotoxicol Environ Saf ; 192: 110310, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32061987

RESUMO

Smilax brasiliensis (Smilacaceae) is a native Brazilian plant found in the Cerrado biome and commonly used in folk medicine. The aim of this study was to evaluate the allelopathic, cytotoxic, genotoxic, and antigenotoxic potential of extract and fractions of Smilax brasiliensis leaves. Quercetin and rutin isomers were observed in the subfractions. The dichloromethane fraction (1000 µg/mL) decreased lettuce (Lactuca sativa) seed vigor, while and ethyl acetate and hydromethanol fractions (1000 µg/mL) affected the germination, and quercetin and rutin affected the vigor and germination of onion seeds. The extract, fractions, quercetin, and rutin inhibited or promoted lettuce hypocotyl and radicle growth. The extract and fractions inhibited onion hypocotyl growth at all concentrations. With regards to radicle growth, the results were diversified: growth was either inhibited or promoted. Rutin and quercetin inhibited onion hypocotyl and radicle growth at all concentrations. The extract and fractions of Smilax brasiliensis, rutin, and quercetin did not cause cytotoxic effect evaluated by mitotic index. The extract and fractions showed genotoxic effects. Quercetin and rutin did not cause genotoxic effects. On the other hand, the extract and fractions showed antigenotoxic effects at all tested concentrations, where they were able to revert chromosomal abnormalities caused by glyphosate. However, additional studies are required to evaluate the possible use of the S. brasiliensis leaf methanol extract and fractions as natural sources of bioherbicides.


Assuntos
Quercetina/toxicidade , Rutina/toxicidade , Smilax/química , Alelopatia , Citotoxinas/toxicidade , Dano ao DNA/efeitos dos fármacos , Germinação/efeitos dos fármacos , Alface/efeitos dos fármacos , Cebolas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Folhas de Planta/química , Quercetina/farmacologia , Rutina/farmacologia , Sementes/efeitos dos fármacos
18.
Ecotoxicol Environ Saf ; 192: 110328, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32078840

RESUMO

In this study pillar[5]arene (P5) and a quinoline-functionalized pillar[5]arene (P5-6Q) which is used for detecting radioactive element, gas adsorption and toxic ions were synthesized. These materials were characterized by Nuclear Magnetic Resonance (NMR), Fourier Transform Infrared (FTIR), elemental analysis, melting point, Mass Spectroscopy, Scanning Electron Microscopy (SEM) and Zeta Potential. The cytotoxic and genotoxic potential of P5 and P5-6Q at distinct concentrations of 12.5, 25, 50, and 100 µg/mL were also investigated by Allium ana-telophase and comet assays on Allium cepa roots and Drosophila melanogaster haemocytes. P5 and P5-6Q showed dose dependent cytotoxic effect by decreasing mitotic index (MI) and genotoxic effect by increasing chromosomal aberrations (CAs such as disturbed anaphase-telophase, polyploidy, stickiness, chromosome laggards and bridges) and DNA damage at the exposed concentrations. These changes in P5-6Q were lower than P5. Further research is necessary to clarify the cytotoxic and genotoxic action mechanisms of P5 and P5-6Q at molecular levels.


Assuntos
Calixarenos/toxicidade , Dano ao DNA , Drosophila melanogaster/efeitos dos fármacos , Cebolas/efeitos dos fármacos , Anáfase/efeitos dos fármacos , Animais , Calixarenos/química , Aberrações Cromossômicas , Ensaio Cometa , Citotoxinas/química , Citotoxinas/toxicidade , Drosophila melanogaster/genética , Hemócitos/efeitos dos fármacos , Índice Mitótico , Cebolas/genética , Raízes de Plantas/efeitos dos fármacos , Quinolinas/síntese química , Quinolinas/química , Quinolinas/toxicidade , Telófase/efeitos dos fármacos
19.
Sci Total Environ ; 713: 136694, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32019035

RESUMO

The relative ease with which cadmium (Cd) in agricultural soils can transfer to crop plants can pose a potential health risk to consumers. However, efforts to predict and mitigate these risks are often confounded by the various factors that influence metal accumulation in the edible plant parts. The aim of this work was to identify key drivers that determine Cd concentrations in spinach leaves, potato tubers, onion bulbs and wheat grain grown in commercial horticultural operations across New Zealand (NZ). Paired soil and plant samples (n = 147) were collected from farms across different NZ growing regions. Cadmium concentrations in the edible parts were measured and four different tests were used to examine the potential bioavailability of soil Cd: pseudo-total and porewater concentrations, 0.05 M Ca(NO3)2-extraction and diffusive gradients in thin-films (DGT). Information on a range of soil and climatic variables was also collected. The methods' ability to represent Cd concentrations in the plant parts was assessed through single and multiple regression analysis that considered the different variables and the farm locations. Soil Cd concentrations determined by the different tests were positively related to plant concentrations and there were clear regional differences between these relationships. The Ca(NO3)2 extraction predicted over 76% of the variability in Cd concentrations in onion bulbs and spinach leaves, while DGT and porewater Cd provided the best estimates for potato tubers and wheat grains, respectively, once regional differences were considered, along with certain environmental and soil variables. The results show that certain soil and environmental factors can be a key influence for determining Cd accumulation in the edible parts of some plants and that regional differences are important for modulating the extent to which this occurs. These effects should be considered when trying to mitigate the potential risks arising from Cd in agricultural soils.


Assuntos
Solo , Cádmio , Nova Zelândia , Cebolas , Poluentes do Solo , Solanum tuberosum , Spinacia oleracea , Triticum
20.
Mutat Res ; 849: 503142, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32087856

RESUMO

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.


Assuntos
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/ultraestrutura
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