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1.
Environ Monit Assess ; 192(4): 232, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32166379

RESUMO

Copper oxide nanoparticles (CuO NPs) have been extensively explored for use in agriculture. Previous studies have indicated that application of CuO NPs might be promising for development and conservation of plants, pest control, and for the recovery of degraded soils. However, depending on the applied concentration copper can cause phytotoxic effects. In this work, biosynthesized CuO NPs (using green tea extract) were evaluated on their effects on lettuce (Lactuca sativa L.) seedling growth, which were exposed at concentrations ranged between 0.2 and 300 µg mL-1. From the biosynthesized were obtained ultra-small CuO NPs (~ 6.6 nm), with high stability in aqueous suspension. Toxicity bioassays have shown that at low concentrations (up to 40 µg mL-1), CuO NPs did not affect or even enhanced the seed germination. At higher concentrations (higher than 40 µg mL-1), inhibition of seed germination and radicle growth ranging from 35 to 75% was observed. With the increase of CuO NPs concentrations, nitrite and S-nitrosothiols levels in radicles increased, whereas superoxide dismutase and total antioxidant activities decreased. The nitrite and S-nitrosothiols levels in lettuce radicles showed a direct dose response to CuO NP application, which may indicate nitric oxide-dependent signaling pathways in the plant responses. Therefore, the results demonstrated that at low concentrations (≤ 20 µg mL-1) of CuO NPs, beneficial effects are obtained from seedlings, enhancing plant growth, and the involvement of nitric oxide signaling in the phytotoxic effects induced by high concentration of this formulation. Graphical abstract.


Assuntos
Cobre , Alface , Nanopartículas Metálicas , Nanopartículas , Antioxidantes , Cobre/farmacologia , Monitoramento Ambiental , Alface/efeitos dos fármacos , Alface/crescimento & desenvolvimento , Óxido Nítrico , Plântula
2.
Chem Biodivers ; 17(1): e1900508, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31692228

RESUMO

This study aimed to identify the main components of an essential oil produced from leaves of Ambrosia trifida and to evaluate its potential allelopathic effect on seed germination and seedling growth of lettuce, watermelon, cucumber and tomato. The essential oil was obtained by hydrodistillation and characterized chemically by gas chromatography (GC) coupled with both mass spectrometry (MS) and flame ionization detector (FID). Total 69 compounds were identified, with limonene (20.7 %), bornyl acetate (15.0 %), borneol (14.7 %) and germacrene D (11.6 %) as the major components. The working solutions of the essential oil emulsified with Tween 20 and dissolved in distilled water were prepared at four concentration levels (0.01, 0.1, 0.5 % and 1 %, v/v). The results obtained showed that increase in essential oil concentration leads to decrease in seed germination, as well as shoot and radical length of lettuce, watermelon, cucumber and tomato. The obtained data revealed a highly significant effect (p<0.05) between control and 1 % and 0.5 % oil concentrations in all treatments. The essential oil of A. trifida exhibited more powerful phytotoxic effects on lettuce, watermelon and tomato than on cucumber regarding germination and early seedling growth.


Assuntos
Ambrosia/química , Citrullus/efeitos dos fármacos , Cucumis sativus/efeitos dos fármacos , Alface/efeitos dos fármacos , Lycopersicon esculentum/efeitos dos fármacos , Óleos Voláteis/toxicidade , Folhas de Planta/química , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação
3.
Ecotoxicol Environ Saf ; 188: 109923, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31711779

RESUMO

In this work, ecotoxicological bioassays based on Lactuca sativa seeds and bioluminescent bacterium (Vibrio fischeri) have been carried out in order to quantify the toxicity of Norfloxacin (NOR) and sodium sulfate solutions, before and after treating them using electrochemical advanced oxidation. The effect of some process variables (anode material, reactor configuration and applied current) on the toxicity evolution of the treated solution has been studied. A NOR solution shows an EC50(5 days) of 336 mg L-1towards Lactuca sativa. This threshold NOR concentration decreases with sodium sulfate concentration, in solutions that contain simultaneously Norfloxacin and sodium sulfate. In every case considered in this work, the electrochemical advanced oxidation process increased the toxicity (towards both Lactuca sativa and Vibrio fischeri) of the solution. This toxicity increase is mainly due to the persulfate formation during the electrochemical treatment. From a final solution toxicity point of view, the best results were obtained using a BDD anode in a divided reactor applying the lowest current intensity.


Assuntos
Técnicas Eletroquímicas/métodos , Norfloxacino/toxicidade , Poluentes Químicos da Água/toxicidade , Purificação da Água/métodos , Aliivibrio fischeri/efeitos dos fármacos , Boro/química , Cerâmica/química , Diamante/química , Ecotoxicologia , Técnicas Eletroquímicas/instrumentação , Eletrodos , Alface/efeitos dos fármacos , Norfloxacino/análise , Oxirredução , Sulfatos/química , Poluentes Químicos da Água/análise
4.
Food Chem ; 309: 125713, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31708345

RESUMO

The effect of cultivar and nutrient solution macrocation proportions (SK, SCa, SMg) on the bioactive content of hydroponically cultivated lettuce was evaluated on two lettuce cultivars (red and green-pigmented Salanova®) grown in a fully controlled Fitotron® chamber. Fresh weight and color attributes were superior in green Salanova and in SK-treated plants, while elevated macrocation proportions (SK, SCa, and SMg) affected the corresponding minerals, P and Na content. SCa and SMg treatments raised ascorbate concentration and reduced nitrate levels in treated plants. Chicoric and chlorogenic acids were higher in red over green Salanova. Chlorogenic acid was higher in SCa and SMg plants and chicoric acid levels were SMg > SCa > SK. The SMg-treated red Salanova contained higher concentrations of target carotenoids. In conclusion, nutrient solution management constitutes an effective cultural practice to increase bioactive properties and functional quality of hydroponically grown lettuce.


Assuntos
Alface/metabolismo , Compostos Fitoquímicos/análise , Antocianinas/análise , Ácido Ascórbico/análise , Biomassa , Carotenoides/análise , Cátions/química , Ácido Clorogênico/análise , Cor , Genótipo , Alface/efeitos dos fármacos , Alface/genética , Alface/crescimento & desenvolvimento , Minerais/análise , Nutrientes/farmacologia , Compostos Fitoquímicos/metabolismo , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Análise de Componente Principal
5.
Biosci Biotechnol Biochem ; 84(1): 178-186, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31581931

RESUMO

Prohydrojasmon has been reported to improve the quality of crops. However, most previous studies have investigated its application on fruits. Here, we evaluated the effect of prohydrojasmon on the growth and total phenolic content, anthocyanin content, and antioxidant activity in komatsuna (Brassica rapa var. periviridis) and lettuce (Lactuca sativa L.). Prohydrojasmon did not show any serious inhibitory effect. Prohydrojasmon applied to komatsuna at a concentration of 0.5 µM significantly increased the total phenolic content and anthocyanin content, and a concentration of 1 µM increased the antioxidant activity. In lettuce, prohydrojasmon at a concentration of 400 µM significantly increased the total phenolic content and anthocyanin content, while a concentration of 0.5 µM significantly increased the antioxidant activity. These results suggest that prohydrojasmon positively affects the phenolic compound and anthocyanin accumulation and antioxidant activity in komatsuna and lettuce without adversely affecting growth.


Assuntos
Antocianinas/metabolismo , Antioxidantes/metabolismo , Brassica rapa/efeitos dos fármacos , Ciclopentanos/farmacologia , Alface/efeitos dos fármacos , Oxilipinas/farmacologia , Reguladores de Crescimento de Planta/farmacologia , Polifenóis/metabolismo , Brassica rapa/crescimento & desenvolvimento , Ciclopentanos/síntese química , Alface/crescimento & desenvolvimento , Oxilipinas/síntese química , Compostos Fitoquímicos/síntese química , Compostos Fitoquímicos/farmacologia , Reguladores de Crescimento de Planta/síntese química , Polifenóis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Verduras/efeitos dos fármacos
6.
J Agric Food Chem ; 67(45): 12558-12564, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31609622

RESUMO

All four stereoisomers of naturally occurring 6-(2-hydroxy-6-phenylhex-1-yl)-5,6-dihydro-2H-pyran-2-one (1) were synthesized by employing yeast-reduction products with high optical purity [from 95% enantiomeric excess (ee) to more than 99% ee], and then their phytotoxicities against lettuce and Italian ryegrass were evaluated. In the Italian ryegrass seedlings test, (6S,2'R)-1 showed the most potent and stereospecific activity against the shoots (IC50 = 260 µM) and roots (IC50 = 43.2 µM), with a significant difference from other stereoisomers. The highest seed germination inhibitory activity against Italian ryegrass seed was also observed in (6S,2'R)-1, showing a 53% germination ratio from the control at 1000 µM. This advantageous (6S,2'R) stereochemistry was employed in the syntheses of α,ß-dihydro, 2'-dehydroxy, and 2'-methoxy derivatives 13-15. By the test using these derivatives, the importance of the α,ß-unsaturated double bond and hydroxy group bonding to a chiral center on the 6-alkyl chain of 5,6-dihydro-α-pyrone for phytotoxicity was determined. In the test against lettuce, the 6S configuration and (6S,2'S) configuration were necessary for growth inhibition (IC50 = ca. 60 µM) and germination inhibition (63% germination ratio at 1000 µM), respectively.


Assuntos
Carbono/química , Herbicidas/farmacologia , Piranos/química , Carbono/farmacologia , Germinação/efeitos dos fármacos , Herbicidas/síntese química , Herbicidas/química , Alface/efeitos dos fármacos , Alface/crescimento & desenvolvimento , Lolium/efeitos dos fármacos , Lolium/crescimento & desenvolvimento , Estrutura Molecular , Piranos/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade
7.
Chemosphere ; 237: 124540, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31549654

RESUMO

Lead can be immobilized in contaminated soils by phosphate rock (PR) amendment, but its efficiency is generally limited by low solubility of PR. Our study aimed to elucidate whether phosphate solubilizing bacteria (PSB) can promote Pb immobilization through PR solubilization. Results showed that P. ananatis HCR2 and B. thuringiensis GL-1 could effectively solubilize PR by producing citric, glucose, and α-Ketoglutaric acids. In broth assay, phosphate solubilized from PR by PSB rapidly reacted with Pb2+ and formed insoluble lead compounds, as confirmed by scanning electron microscope, energy dispersive X-ray, and X-ray photoelectron spectroscopy. Pot experiment using lettuce (Lactuca sativa L.) and diffusive gradients in thin films (DGT) verified the effectiveness of soil remediation using PR amendment and PSB inoculation, as plant shoot biomass and net photosynthetic rate as well as soil bioavailable phosphate concentration have significantly increased, while the phytoavailability of Pb, Cd, and Zn greatly reduced. This study suggested that PR amendment combined with PSB inoculation could be applied for remediation of agricultural fields contaminated with multiple heavy metals.


Assuntos
Recuperação e Remediação Ambiental/métodos , Chumbo/química , Fosfatos/química , Microbiologia do Solo , Poluentes do Solo/química , Bacillus thuringiensis/fisiologia , Disponibilidade Biológica , Chumbo/farmacocinética , Alface/efeitos dos fármacos , Alface/crescimento & desenvolvimento , Alface/fisiologia , Metais Pesados/análise , Metais Pesados/farmacocinética , Pantoea/fisiologia , Espectroscopia Fotoeletrônica , Fotossíntese/fisiologia , Brotos de Planta/crescimento & desenvolvimento , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/farmacocinética , Solubilidade , Espectrometria por Raios X
8.
Chemosphere ; 237: 124482, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31398608

RESUMO

The increase in the proportion of microplastics in the environment has intensified the interest in phthalate and microplastic contamination in recent years. In this study, we investigated the response of photosynthetic parameters and the antioxidant system of lettuce to di-n-butyl phthalate (DBP) stress and exposure to various concentrations of microplastic polyethylene (MP) for different durations (14 d and 28 d). Lettuce growth, photosynthetic parameters, and chlorophyll content were reduced significantly after MP- and DBP-only treatments and after the combined (MP + DBP) treatments with both pollutants (P < 0.05), when compared with the control. Our findings indicated that the exposure to MP can inhibit growth, hinder photosynthesis, and interfere with the antioxidant defense system in lettuce. Specifically, compared with the DBP-only treatment group, in all MP + DBP treatment groups, the lettuce growth parameters (dry and fresh weights of the leaves and roots and the number of leaves) decreased (P < 0.05). Moreover, the photosynthetic rate, stomatal conductance, transient transpiration rate, fluorescence parameters, chlorophyll content of leaves, and activity of Rubisco decreased, but the intercellular CO2 concentration increased in all MP + DBP treatment groups. The reduction in photosynthesis was attributed to the limitation of non-porosity and inhibition of the photoelectron flow, and the increase in exogenous MP content aggravated the effect of DBP on photosynthesis in lettuce. Compared with the DBP-only group, in all MP + DBP treatment groups, the content of superoxide radicals and hydrogen peroxide in lettuce leaves and roots increased. Antioxidant levels increased with the increase in MP content, except in the 1.0 mg mL-1 MP treatment after 14 d. Although the antioxidant system exhibited certain protective effects in the latter treatment, the cell membranes were still damaged. The degree of damage to cells decreased with the growth of lettuce, but the damage to root tissue always remained higher than that of the leaves. In conclusion, exposure to exogenous MP exacerbated the damage to lettuce by DBP.


Assuntos
Dibutilftalato/toxicidade , Alface/efeitos dos fármacos , Polietileno/toxicidade , Antioxidantes/metabolismo , Clorofila/metabolismo , Peróxido de Hidrogênio/metabolismo , Alface/fisiologia , Fotossíntese/efeitos dos fármacos , Ácidos Ftálicos , Folhas de Planta/metabolismo , Plásticos/metabolismo , Polietileno/metabolismo , Plântula/efeitos dos fármacos
9.
Chemosphere ; 237: 124458, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31376696

RESUMO

Grape pomace (GP) from Vitis labrusca, the main byproduct from "American table wine" production, is recalcitrant to degradation, and its accumulation is a serious problem with negative environmental impacts. In this work, transformation of grape pomace using a steam pretreatment followed by incubation of GP during a 90-day period with six different fungi were evaluated. Several fungi tested reduced the phytotoxicity of water-soluble fraction (WSFd) from steam-pretreated GP after 90 days' incubation to lettuce and tomato seeds. U. botrytis caused the largest effective phytotoxicity reduction of WSFd (used in the concentration range of 10-1.25% p/v) and was the only fungus causing the removal of monoaromatic compounds. Therefore, this procedure with U. botrytis effectively reduces the availability of phytotoxic monoaromatic compounds in GP, which opens a way for the development of guidelines for the management of these wastes and their potential use as organic amendments in agricultural soil.


Assuntos
Ascomicetos/metabolismo , Indústria Alimentícia , Vitis , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/toxicidade , Cromatografia Gasosa-Espectrometria de Massas , Germinação/efeitos dos fármacos , Hidrocarbonetos Aromáticos/análise , Hidrocarbonetos Aromáticos/metabolismo , Resíduos Industriais , Alface/efeitos dos fármacos , Lycopersicon esculentum/efeitos dos fármacos , Sementes/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Testes de Toxicidade/métodos , Vinho
10.
Ecotoxicol Environ Saf ; 183: 109573, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31442809

RESUMO

Aluminum (Al) bioaccumulation by a novel Al and drought tolerant Curtobacterium herbarum strain CAH5 isolated from rhizosphere soil of Beta vulgaris grown in acidic Andisols were examined. The rhizobacterial strain also presented important plant growth promoting traits even with Al and drought stresses under in-vitro conditions in broth. In experiments with a 2-6 mM as initial Al concentrations, the percentages of Al removal by bacteria were 89-93% and 78-91% within 72 h incubation under the normal and drought conditions, respectively. Cytogenotoxicity assay revealed that the toxicity of Al was reduced after bioaccumulation process. In the greenhouse study, formulated bio-inoculant CAH5 significantly improves the Lactuca sativa growth under Al and drought stress by reducing oxidative stress, lipid peroxidation and Al accumulation in plant parts. Our results highlighted that strain CAH5 could be used as a promising bioresource for restoration of agricultural soil with presence of phytotoxic Al improving crop production even under drought conditions.


Assuntos
Actinobacteria/fisiologia , Alumínio/metabolismo , Secas , Alface/crescimento & desenvolvimento , Reguladores de Crescimento de Planta/fisiologia , Actinobacteria/metabolismo , Alumínio/toxicidade , Biodegradação Ambiental , Caryophyllales/crescimento & desenvolvimento , Caryophyllales/microbiologia , Alface/efeitos dos fármacos , Alface/microbiologia , Reguladores de Crescimento de Planta/metabolismo , Rizosfera , Microbiologia do Solo , Estresse Fisiológico/efeitos dos fármacos
11.
Food Microbiol ; 84: 103226, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31421764

RESUMO

Atmospheric cold plasma (ACP) is an effective method for microbiological decontamination. This study evaluated an alternative water-based decontamination approach for inactivation of bacterial population from fresh produce and in the wash water generated from fresh produce washing. The study characterised ACP inactivation of attached Listeria innocua and Pseudomonas fluorescens inoculated on lettuce in comparison to chlorine treatment. P. fluorescens was sensitive to ACP treatment and was reduced below detection limit within 3 min of treatment. L. innocua population was reduced by ∼2.4 Log10 CFU/g after 5 min of treatment; showing similar inactivation efficacy to chlorine treatment. The microbial load in wash water was continuously decreased and was below detection limits after 10 min of ACP treatment. Micro-bubbling along with agitation assisted the bacterial detachment and distribution of reactive species, thus increasing bacterial inactivation efficacy from fresh produce and wash water. A shift in pH of plasma functionalised water was observed along with high concentration of nitrate and ozone with a relative amount of nitrites which increased with plasma exposure time. Further, L. innocua treated at different independent pH conditions showed minimal or no effect of pH on ACP bacterial inactivation efficacy. Aqueous ACP treatment poses a promising alternative for decontamination of fresh produce and the associated wash-waters which could be applied in the food industry to replace continuous chlorine dosing of process waters.


Assuntos
Cloro/farmacologia , Desinfetantes/farmacologia , Microbiologia de Alimentos/métodos , Alface/microbiologia , Gases em Plasma , Aderência Bacteriana/efeitos dos fármacos , Contagem de Colônia Microbiana , Descontaminação/métodos , Contaminação de Alimentos/análise , Manipulação de Alimentos , Alface/efeitos dos fármacos , Listeria monocytogenes/efeitos dos fármacos , Pseudomonas fluorescens/efeitos dos fármacos , Água/análise
12.
Environ Sci Pollut Res Int ; 26(25): 26216-26228, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31286378

RESUMO

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. friedrichsthalianum, and P. gaudichaudianum on the germination and root growth of Lactuca sativa and Sorghum bicolor, and to evaluate their action on the cell cycle of root meristematic cells of L. sativa. The main compound found in all the studied species was (E)-caryophyllene (P. cattleianum-23.4 %; P. myrtoides-19.3%; P. friedrichsthalianum-24.6% and P. gaudichaudianum-17.0%). The different essential oils were tested at different concentrations on L. sativa and S. bicolor, reducing germination, germination speed index, and root and shoot growth of lettuce and sorghum seedlings. The cytotoxicity and aneugenic potential of these oils were evidenced by the reduction of the mitotic index and increase of the frequency of chromosomal alterations in L. sativa. The essential oils of the species of Psidium studied have potential to be used in weeds control.


Assuntos
Germinação/efeitos dos fármacos , Herbicidas/farmacologia , Alface/efeitos dos fármacos , Meristema/química , Óleos Voláteis/química , Óleos Vegetais/farmacologia , Psidium/química , Plântula/efeitos dos fármacos , Sorghum/química , Alelopatia , Herbicidas/química , Alface/química , Compostos Fitoquímicos , Psidium/efeitos dos fármacos , Sesquiterpenos
13.
PLoS One ; 14(6): e0218368, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31220125

RESUMO

Decoupled aquaponic systems have the potential to become one of the most effective sustainable production systems for the combined production of animal protein and plant crops. Here, recirculating aquaculture systems for fish production are combined with hydroponics for soilless plant production thereby recycling dissolved nutrients derived from metabolism of the fish. The aim of the present study was to characterize hydroponic lettuce production using conventional nutrient solution in comparison with decoupled aquaponics using the nutrient rich fish water as basis for the nutrient solution being supplemented by missing nutrients. In addition, one aquaponic treatment became disinfected in order to assess any occurring advantage of the aquaponics derived fish water. For evaluation the temperature, electrical conductivity, pH, and the mineral composition of the nutrient solution, as well as colony forming units in the fish water were monitored. Additionally, plant growth (fresh and dry weight, number and area of leaves) and quality parameters of lettuce leaves (nitrate, mineral content, phenolic compounds) were examined. Carbon sources and microorganisms derived from fish water seem to have neither beneficial nor detrimental effects on plant growth in this study. Except for some differences in the mineral content of the lettuce leaves, all other quality parameters were not significantly different. The use of aquaponic fish water saved 62.8% mineral fertilizer and fully substituted the required water for the nutrient solution in comparison to the control. Additionally, the reduced fertilizer demand using decoupled aquaponics can contribute to reduce greenhouse gas emissions of an annual lettuce production site per ha by 72% due to saving the energy for fertilizer production. This study clearly demonstrates the huge potential of the innovative approach of decoupled aquaponics to foster the transformation of our conventional agriculture towards sustainable production systems saving resources and minimizing emissions.


Assuntos
Aquicultura , Gases de Efeito Estufa , Alface/crescimento & desenvolvimento , Desinfecção , Fertilizantes/efeitos adversos , Humanos , Hidroponia , Compostos Inorgânicos/química , Alface/efeitos dos fármacos , Nitratos/química , Nutrientes/química , Fenóis/química
14.
Bull Environ Contam Toxicol ; 103(3): 453-460, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31183504

RESUMO

The accumulation of strontium (Sr) in lettuce and radish under 0 (control), 0.5, 1, 2.5, 5, and 10 mM Sr treatments in hydroponic solution at 16, 23 and 30 days and the effects of Sr stress on six nutrient elements in plants were investigated. The results showed that Sr concentrations in plant aerial and underground parts increased in low-Sr treatments (0.5, 1 and 2.5 mM) and fluctuated in high-Sr treatments (5 and 10 mM) throughout the three sampling periods. Sr concentrations were higher in roots than in leaves, reaching 108.8 ± 14.7 and 134.1 ± 1.2 mg/g in lettuce and radish roots, respectively, after 10 mM Sr treatment. Translocation factor (TF) values (ratio of the Sr concentrations in aerial parts to that in roots) were inversely related to the Sr content in the hydroponic solution, and reached 1.45 ± 0.17 to 0.15 ± 0.03 and 1.06 ± 0.20 to 0.12 ± 0.004 for lettuce and radish. The variation in chlorophyll content was consistent with that in plant biomass.


Assuntos
Hidroponia , Alface/metabolismo , Raphanus/metabolismo , Estrôncio/metabolismo , Poluentes Químicos da Água/metabolismo , Transporte Biológico/efeitos dos fármacos , Biomassa , Clorofila/metabolismo , Alface/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raphanus/efeitos dos fármacos , Estrôncio/toxicidade , Poluentes Químicos da Água/toxicidade
15.
Environ Pollut ; 252(Pt A): 706-714, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31185360

RESUMO

Treated wastewater is increasingly used to meet agriculture's water needs; however, treated wastewater contains numerous contaminants of emerging concern (CECs). With exposure and uptake of CECs, phytotoxicity and health of crop plants is of concern, but is poorly understood. This study evaluated the effect of low-dose, chronic exposure to a mixture of 10 CECs, including 4 antibiotics, 3 anti-inflammatory drugs, 1 antiepileptic, 1 beta-blocker, and 1 antimicrobial, on lettuce (Lactuca sativa) and cucumber (Cucumis sativa L.) plants. The CEC mixture was added in nutrient media at 1 to 20X of their typical levels in treated wastewater effluents. Biological endpoints including germination, growth, phytohormone homeostasis, and CEC bioaccumulation were determined. Exposure to the CEC mixture did not affect the germination rate of lettuce seeds, but stimulated root elongation and increased the root-to-shoot biomass ratio during a 7 d cultivation. A dose-dependent decrease in biomass was observed in cucumber seedling after a 30 d exposure, with the highest rate CEC treatment resulting in decreases of 51.2 ±â€¯20.9, 26.3 ±â€¯34.1, and 33.2 ±â€¯41.7% in the below-ground, above-ground, and total biomass, respectively. Levels of abscisic acid were significantly elevated (p < 0.05) in the leaves, but decreased (p < 0.05) in the roots. The dose-response of auxin was characterized by a hormesis effect. A significant 6-fold increase in the stem auxin level was observed at the 1X CEC rate, followed by a decrease to 2-fold the control at the 20X rate. Leaf auxin concentrations also significantly increased at the 1X CEC rate to 16-fold, followed by a decrease at the highest CEC rate. The results of this study suggeste that chronic exposure to low levels of CEC mixtures may compromise the fitness of plants, and the impairments are underlined by alterations in hormone balances.


Assuntos
Cucumis sativus/efeitos dos fármacos , Alface/efeitos dos fármacos , Águas Residuárias/química , Poluentes Químicos da Água/toxicidade , Cucumis sativus/crescimento & desenvolvimento , Cucumis sativus/metabolismo , Germinação/efeitos dos fármacos , Homeostase , Hormese , Alface/crescimento & desenvolvimento , Alface/metabolismo , Desenvolvimento Vegetal/efeitos dos fármacos , Reguladores de Crescimento de Planta/metabolismo , Poluentes Químicos da Água/química
16.
J Agric Food Chem ; 67(25): 6911-6920, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31194542

RESUMO

Improving the root system architecture (RSA) under adverse environmental conditions by using biostimulants is emerging as a new way to boost crop productivity. Recently, we have reported the characterization of novel chitosan-based microparticles (CS-MPs) with promising biological properties as rooting agents in lettuce. In this work, we demonstrated that in contrast to bulk chitosan (CS), which exerts root growth inhibition, CS-MPs promoted root growth and development from 1 to 10 µg mL-1 without cytotoxicity effects at higher doses in Arabidopsis and lettuce seedlings. In addition, we studied the mechanistic mode of action of CS-MPs in the development of early RSA in the Arabidopsis model. CS-MPs unchained accurate and sustained spatio-temporal activation of the nuclear auxin signaling pathway. Our findings validated a promising scenario for the application of CS-MPs in the modulation of RSA to respond to changing soil environments and improve crop performance.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Quitosana/química , Quitosana/farmacologia , Ácidos Indolacéticos/farmacologia , Alface/crescimento & desenvolvimento , Raízes de Plantas/crescimento & desenvolvimento , Arabidopsis/efeitos dos fármacos , Alface/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
17.
Ecotoxicology ; 28(6): 631-642, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31161525

RESUMO

Understanding the effects of many essential non-steroidal anti-inflammatory drugs (NSAIDs) on plants is still limited, especially at environmentally realistic concentrations. This paper presents the influence of three of the most frequently used NSAIDs (diclofenac, ibuprofen, and naproxen) at environmentally realistic concentrations on the autochthonous green leafy vegetables: orache (Atriplex patula L.), spinach (Spinacia oleracea L.) and lettuce (Lactuca sativa L.). Our research was focused on the determination of the photosynthetic parameters, the emission rate of volatile organic compounds, and the evaluation of the ultrastructure of leaves of studied vegetables after exposure to abiotic stress induced by environmental pollutants, namely NSAIDs. The data obtained indicate a moderate reduction of foliage physiological activity as a response to the stress induced by NSAIDs to the selected green leafy vegetables. The increase of the 3-hexenal and monoterpene emission rates with increasing NSAIDs concentration could be used as a sensitive and a rapid indicator to assess the toxicity of the NSAIDs. Microscopic analysis showed that the green leafy vegetables were affected by the selected NSAIDs. In comparison to the controls, the green leafy vegetables treated with NSAIDs presented irregular growth of glandular trichomes on the surface of the adaxial side of the leaves, less stomata, cells with less cytoplasm, irregular cell walls and randomly distributed chloroplasts. Of the three NSAIDs investigated in this study, ibuprofen presented the highest influence. The results obtained in this study can be used to better estimate the impact of drugs on the environment and to improve awareness on the importance of the responsible use of drugs.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Atriplex/efeitos dos fármacos , Poluentes Ambientais/efeitos adversos , Alface/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Spinacia oleracea/efeitos dos fármacos , Compostos Orgânicos Voláteis/metabolismo , Atriplex/fisiologia , Atriplex/ultraestrutura , Diclofenaco/efeitos adversos , Ibuprofeno/efeitos adversos , Alface/fisiologia , Alface/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Naproxeno/efeitos adversos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/ultraestrutura , Spinacia oleracea/fisiologia , Spinacia oleracea/ultraestrutura
18.
Ecotoxicol Environ Saf ; 180: 63-72, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31075717

RESUMO

In the present study, a potent Aluminum (Al) resistant yeast strain CAM4 was isolated from rhizosphere soil of Rubus geoides, grown in acidic Andisols and identified as Rhodotorula mucilaginosa by 18S rRNA gene sequence analysis. The strain CAM4 was selected in terms of abiotic stress tolerance to Al, salinity and drought with multiple plant growth promoting (PGP) traits. Besides, strain CAM4 also exhibited Al removal efficiency (80-88%) from the culture medium even under combined stresses of salinity and drought. The sawdust-based formulation of strain CAM4 (sawdust-molasses 5%-PEG 1%-strain CAM4) showed higher cell viability of up to 24 weeks (8.54 log CFU g-1). Inoculation of formulated strain CAM4 significantly enhanced the various morphological and biochemical characters of Lactuca sativa grown under abiotic stress conditions. The formulated strain CAM4 also reduced the accumulation of Al in L. sativa as well that conferring Al tolerance to the plants. The study concludes that strain CAM4 could be used as a biofertilizer for healthy and safe crop production in soils, with Al toxicity as well as combined salt and drought stresses.


Assuntos
Alumínio/toxicidade , Secas , Alface/efeitos dos fármacos , Rhodotorula/crescimento & desenvolvimento , Salinidade , Microbiologia do Solo , Estresse Fisiológico/efeitos dos fármacos , Alface/crescimento & desenvolvimento , Rizosfera , Solo/química
19.
Molecules ; 24(9)2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31072064

RESUMO

Safranal, the main volatile chemical of Saffron (Crocus sativus) was studied to estimate its allelopathic effects on the photosynthetic pigment chlorophyll, leaf electrolyte leakage, fresh weight, catalase (CAT), and peroxidase (POX) activity of the test plant Lettuce (Lactuca sativa). In this study, the effective concentration (EC50) of safranal on CAT was estimated to be 6.12 µg/cm3. CAT activity was inhibited in a dose-dependent manner by the increase in the safranal concentration while POX activity was increased. Moreover, Safranal caused significant physiological changes in chlorophyll content, leaf electrolyte leakage, and fresh weight of several weed species with Lolium multiflorum being the most sensitive. Furthermore, 5 µM Safranal showed significant inhibitory activity against dicotyledonous in comparison to the monocotyledons under greenhouse conditions. The inhibition of the CAT by safranal was similar to those of uncompetitive inhibitors, and therefore the decline in carbon fixation by plants might be the mechanism behind the inhibitory activity of safranal.


Assuntos
Crocus/química , Cicloexenos/farmacologia , Alface/fisiologia , Feromônios/farmacologia , Plantas Daninhas/fisiologia , Terpenos/farmacologia , Catalase/metabolismo , Domínio Catalítico , Cicloexenos/química , Glutationa Peroxidase/metabolismo , Alface/efeitos dos fármacos , Pigmentação/efeitos dos fármacos , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/crescimento & desenvolvimento , Espécies Reativas de Oxigênio/metabolismo , Terpenos/química , Compostos Orgânicos Voláteis/farmacologia
20.
Ecotoxicol Environ Saf ; 180: 295-308, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31100594

RESUMO

Crops can become contaminated when grown in soils containing heavy metals. Cadmium is a heavy metal that poses a significant health risk to humans. The purpose of this study was to evaluate the effect of cadmium on lettuce (Lactuca sativa Linn) and the contamination risk of lettuce grown in cadmium environments. The results showed that photosynthesis and growth parameters were significantly affected by cadmium. Lettuce has the ability to absorb large amounts of cadmium from the contaminated environment and so is a cadmium hyperaccumulator plant. The study showed that approximately 35% of the total absorbed cadmium is transmitted to aerial and edible parts of lettuce. This study was undertaken as lettuce has the ability to absorb and accumulate high levels of cadmium. There are however are no reports on the PCS gene and the potential for high cadmium accumulation in lettuce. The bioinformatics study revealed that lettuce has two phytochelatin synthase genes that produce 6 PCSs through splicing leading to the ability of lettuce to store high levels of cadmium. These six sequences although different in length have high similarity. Sequence structure, cellular location, three-dimensional structure, phylogeny and a comparison of their catalytic power were evaluated. The high accumulation of cadmium in lettuce and the presence of several PCSs contribute to the accumulation of cadmium in aerial tissues. The cultivation of lettuce in contaminated environments led us to evaluate suspected farms for the presence of cadmium in produce. Lettuce grown in industrial environments contaminated with cadmium can pose a serious threat to human health.


Assuntos
Aminoaciltransferases/genética , Cádmio/toxicidade , Alface/efeitos dos fármacos , Poluentes do Solo/toxicidade , Solo/química , Cádmio/análise , Cádmio/metabolismo , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/enzimologia , Alface/enzimologia , Fotossíntese/efeitos dos fármacos , Poluentes do Solo/análise , Poluentes do Solo/metabolismo , Inquéritos e Questionários
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