RESUMO
White mold is an agricultural disease caused by the fungus Sclerotinia sclerotiorum, which affects important crops. There are different ways of controlling this organism, but none provides inhibition of its resistance structures (sclerotia). Nanotechnology offers promising applications in agricultural area. Here, silver nanoparticles were biogenically synthesized using the fungus Trichoderma harzianum and characterized. Cytotoxicity and genotoxicity were evaluated, and the nanoparticles were initially tested against white mold sclerotia. Their effects on soybean were also investigated with no effects observed. The nanoparticles showed potential against S. sclerotiorum, inhibiting sclerotia germination and mycelial growth. Nanoparticle characterization data indicated spherical morphology, satisfactory polydispersity and size distribution. Cytotoxicity and genotoxicity assays showed that the nanoparticles caused both the effects, although, the most toxic concentrations were above those applied for white mold control. Given the potential of the nanoparticles against S. sclerotiorum, we conclude that this study presents a first step for a new alternative in white mold control.
Assuntos
Antifúngicos/farmacologia , Ascomicetos/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Micélio/efeitos dos fármacos , Prata/farmacologia , Trichoderma/química , Células A549 , Animais , Antifúngicos/química , Ascomicetos/crescimento & desenvolvimento , Sobrevivência Celular/efeitos dos fármacos , Aberrações Cromossômicas/efeitos dos fármacos , Células HeLa , Humanos , Nanopartículas Metálicas/química , Camundongos , Testes de Sensibilidade Microbiana , Índice Mitótico , Micélio/crescimento & desenvolvimento , Células NIH 3T3 , Cebolas/citologia , Cebolas/efeitos dos fármacos , Oxirredução , Tamanho da Partícula , Doenças das Plantas/microbiologia , Doenças das Plantas/terapia , Prata/química , Glycine max/efeitos dos fármacos , Glycine max/microbiologia , Trichoderma/metabolismoRESUMO
The use of lower concentrations and fewer applications of herbicides is one of the prime objectives of the sustainable agriculture as it decreases the toxicity to non-targeted organisms and the risk of wider environmental contamination. In the present work, nanoparticles were developed for encapsulation of the herbicides imazapic and imazapyr. Alginate/chitosan and chitosan/tripolyphosphate nanoparticles were manufactured, and their physicochemical stability was evaluated. Determinations were made of the encapsulation efficiency and release kinetics, and the toxicity of the nanoparticles was evaluated using cytotoxicity and genotoxicity assays. The effects of herbicides and herbicide-loaded nanoparticles on soil microorganisms were studied in detail using real-time polymerase chain reactions. The nanoparticles showed an average size of 400 nm and remained stable during 30 days of storage at ambient temperature. Satisfactory encapsulation efficiencies of between 50 and 70% were achieved for both types of particles. Cytotoxicity assays showed that the encapsulated herbicides were less toxic, compared to the free compounds, and genotoxicity was decreased. Analyses of soil microbiota revealed changes in the bacteria of the soils exposed to the different treatments. Our study proves that encapsulation of the herbicides improved their mode of action and reduced their toxicity, indicating their suitability for use in future practical applications.
Assuntos
Quitosana , Portadores de Fármacos , Herbicidas/administração & dosagem , Imidazóis/administração & dosagem , Nanopartículas , Niacina/análogos & derivados , Ácidos Nicotínicos/administração & dosagem , Quitosana/química , Ensaio Cometa , Portadores de Fármacos/química , Composição de Medicamentos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Herbicidas/química , Herbicidas/toxicidade , Imidazóis/química , Imidazóis/toxicidade , Cinética , Microbiota/efeitos dos fármacos , Nanopartículas/química , Niacina/administração & dosagem , Niacina/química , Niacina/toxicidade , Ácidos Nicotínicos/química , Ácidos Nicotínicos/toxicidade , Microbiologia do SoloRESUMO
Carbendazim (MBC) (methyl-2-benzimidazole carbamate) and tebuconazole (TBZ) ((RS)-1-(4-chlorophenyl)-4,4-dimethyl-3-(1H-1,2,4-triazol-1-ylmethyl)pentan-3-ol) are widely used in agriculture for the prevention and control of fungal diseases. Solid lipid nanoparticles and polymeric nanocapsules are carrier systems that offer advantages including changes in the release profiles of bioactive compounds and their transfer to the site of action, reduced losses due to leaching or degradation, and decreased toxicity in the environment and humans. The objective of this study was to prepare these two types of nanoparticle as carrier systems for a combination of TBZ and MBC, and then investigate the release profiles of the fungicides as well as the stabilities and cytotoxicities of the formulations. Both nanoparticle systems presented high association efficiency (>99%), indicating good interaction between the fungicides and the nanoparticles. The release profiles of MBC and TBZ were modified when the compounds were loaded in the nanoparticles, and cytotoxicity assays showed that encapsulation of the fungicides decreased their toxicity. These fungicide systems offer new options for the treatment and prevention of fungal diseases in plants.
Assuntos
Agricultura , Benzimidazóis/administração & dosagem , Carbamatos/administração & dosagem , Preparações de Ação Retardada , Fungicidas Industriais/administração & dosagem , Lipídeos , Nanopartículas , Polímeros , Triazóis/administração & dosagem , Química Farmacêutica , Estabilidade de Medicamentos , Modelos Teóricos , Nanocápsulas , Tamanho da PartículaRESUMO
This review article discusses the use of nanotechnology in combination with botanical insecticides in order to develop systems for pest control in agriculture. The main types of botanical insecticides are described, together with different carrier systems and their potential uses. The botanical insecticides include those based on active principles isolated from plant extracts, as well as essential oils derived from certain plants. The advantages offered by the systems are highlighted, together with the main technological challenges that must be resolved prior to future implementation of the systems for agricultural pest control. The use of botanical insecticides associated with nanotechnology offers considerable potential for increasing agricultural productivity, while at the same time reducing impacts on the environment and human health.