Effects of Silver Nanoparticles on Heterotrophic Bacterial Community Inhabiting the Anoxic Paddy Soil of Flooded Rice Microcosms

2017 ◽  
Vol 866 ◽  
pp. 152-155
Author(s):  
Duongruitai Nicomrat ◽  
Siriphatrc Chamutpong
Keyword(s):  
Silver Nanoparticles ◽  
Paddy Soil ◽  
Heterotrophic Bacteria ◽  
Rice Paddy ◽  
Antimicrobial Activities ◽  
High Concentration ◽  
Negative Effects ◽  
Bacterial Populations ◽  
Wide Range ◽  
Anoxic Paddy Soil

Although silver nanoparticles (AgNPs) have been applied more in our daily life. They are well known for their antimicrobial activities against a wide range of organisms but more concerns on the negative effects of AgNP products contaminated to the environment especially on most microorganism niches related to nutrient cycling in ecosystem. In the study, research was done to in understand the effects of AgNPs on heterotrophic bacterial populations in rice paddy soil. Both culturable N2-fixing bacteria and common heterotrophic bacteria could adapt themselves to AgNPs at low concentration (less than 50 ppm). However, more distinct reduction in N2-fixing bacteria against AgNPs were detected than heterotrophic bacterial niches at least 100 ppm AgNPs . These evidences indicated AgNPs at high concentration had significant adverse effects on the diverse microbial consortiums as well as rice seedlings.

scholarly journals Dynamics and Activity of Iron-Reducing Bacterial Populations in a West African Rice Paddy Soil under Subsurface Drainage: Case Study of Kamboinse in Burkina Faso

2015 ◽  
Vol 06 (08) ◽  
pp. 860-869 ◽  
Author(s):  
Cécile Harmonie Otoidobiga ◽  
Amadou Keita ◽  
Hamma Yacouba ◽  
Alfred S. Traore ◽  
Dayéri Dianou
Keyword(s):  
Burkina Faso ◽  
Paddy Soil ◽  
Rice Paddy ◽  
Subsurface Drainage ◽  
West African ◽  
Rice Paddy Soil ◽  
Bacterial Populations ◽  
African Rice

scholarly journals Defect-assisted synthesis of magneto-plasmonic silver-spinel ferrite heterostructures in a flower-like architecture

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Marco Sanna Angotzi ◽  
Valentina Mameli ◽  
Claudio Cara ◽  
Vincenzo Grillo ◽  
Stefano Enzo ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Spinel Ferrite ◽  
High Resolution Electron Microscopy ◽  
Careful Study ◽  
X Ray Diffraction ◽  
High Concentration ◽  
Resolution Electron ◽  
Wide Range ◽  
Controlled Morphology ◽  
Diffraction Patterns

Abstract Artificial nano-heterostructures (NHs) with controlled morphology, obtained by combining two or more components in several possible architectures, make them suitable for a wide range of applications. Here, we propose an oleate-based solvothermal approach to design silver-spinel ferrite flower-like NHs. Small oleate-coated silver nanoparticles were used as seeds for the growth of magnetic spinel ferrite (cobalt ferrite and spinel iron oxide) nanodomains on their surface. With the aim of producing homogeneous flower-like heterostructures, a careful study of the effect of the concentration of precursors, the reaction temperature, the presence of water, and the chemical nature of the spinel ferrite was carried out. The magnetic and optical properties of the NHs were also investigated. A heterogeneous growth of the spinel ferrite phase on the silver nanoparticles, through a possible defect-assisted mechanism, was suggested in the light of the high concentration of stacking faults (intrinsic and twins) in the silver seeds, revealed by Rietveld refinement of powder X-ray diffraction patterns and High-Resolution electron microscopy.

scholarly journals Hydroxymethylfurfural Affects Caged Honey Bees (Apis mellifera carnica)

Diversity ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 18 ◽  
Author(s):  
Aleš Gregorc ◽  
Snežana Jurišić ◽  
Blair Sampson
Keyword(s):  
Apis Mellifera ◽  
Honey Bee ◽  
Honey Bees ◽  
Immunohistochemical Analysis ◽  
Cellular Level ◽  
High Concentration ◽  
Negative Effects ◽  
Apis Mellifera Carnica ◽  
Wide Range ◽  
Bee Health

A high concentration of hydroxymethylfurfural (HMF) (e.g., 15 mg HMF per kg honey) indicates quality deterioration for a wide range of foods. In honey bee colonies, HMF in stored honey can negatively affect bee health and survival. Therefore, in the laboratory, we experimentally determined the effects of HMF on the longevity and midgut integrity of worker Apis mellifera carnica by feeding bees standard diets containing five concentrations of HMF (100, 500, 1000, and 1500 ppm). Simultaneously, we also examined HMF’s effect on Nosema ceranae spore counts within infected honey bees. We performed an immunohistochemical analysis of the honey bee midgut to determine possible changes at the cellular level. No correlation was established between HMF concentration and N. ceranae spore counts. Negative effects of HMF on bees were not observed in the first 15 days of exposure. However, after 15 to 30 days of exposure, HMF caused midgut cells to die and an increased mortality of honey bee workers across treatment groups.

scholarly journals Coating-Dependent Effects of Silver Nanoparticles on Tobacco Seed Germination and Early Growth

2020 ◽  
Vol 21 (10) ◽  
pp. 3441 ◽  
Author(s):  
Renata Biba ◽  
Dajana Matić ◽  
Daniel Mark Lyons ◽  
Petra Peharec Štefanić ◽  
Petra Cvjetko ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Growth Parameters ◽  
Antimicrobial Properties ◽  
Chemical Properties ◽  
Early Growth ◽  
Consumer Products ◽  
Negative Effects ◽  
Wide Range ◽  
Living Organisms ◽  
The Stability

Silver nanoparticles (AgNPs) are used in a wide range of consumer products because of their excellent antimicrobial properties. AgNPs released into the environment are prone to transformations such as aggregation, oxidation, or dissolution so they are often stabilised by coatings that affect their physico-chemical properties and change their effect on living organisms. In this study we investigated the stability of polyvinylpyrrolidone (PVP) and cetyltrimethylammonium bromide (CTAB) coated AgNPs in an exposure medium, as well as their effect on tobacco germination and early growth. AgNP-CTAB was found to be more stable in the solid Murashige and Skoog (MS) medium compared to AgNP-PVP. The uptake and accumulation of silver in seedlings was equally efficient after exposure to both types of AgNPs. However, AgNP-PVP induced only mild toxicity on seedlings growth, while AgNP-CTAB caused severe negative effects on all parameters, even compared to AgNO3. Moreover, CTAB coating itself exerted negative effects on growth. Cysteine addition generally alleviated AgNP-PVP-induced negative effects, while it failed to improve germination and growth parameters after exposure to AgNP-CTAB. These results suggest that the toxic effects of AgNP-PVP are mainly a consequence of release of Ag+ ions, while phytotoxicity of AgNP-CTAB can rather be ascribed to surface coating itself.

Brief history and ways of further development of the department of hydraulic engineering and hydraulics FSBI «VNIIGiM named after A.N. Kostyakov»

2020 ◽  
pp. 18-23
Author(s):  
Alexey Shcherbakov ◽  
Valentin Zhezmer
Keyword(s):  
Land Reclamation ◽  
Water Source ◽  
Water Sources ◽  
Hydraulic Engineering ◽  
Negative Effects ◽  
Extensive Experience ◽  
Safety Level ◽  
Theoretical Substantiation ◽  
Wide Range ◽  
Construction Operation

Department of hydraulic engineering and hydraulics FGBNU «VNIIGiM them. A.N. Kostyakova «has a long history. For many years, the department’s staff has been such scientists and water engineers with extensive experience as M.A. Volynov, V.S. Verbitsky, S.S. Medvedev, N.V. Lebedev, B.C. Panfilov, T.G. Voynich-Syanozhentsky, V.A. Golubkova, G.V. Lyapin and others. The department solved a wide range of tasks, the main areas of research were the following: – theoretical and applied hydrodynamics and hydraulics, with reference to the open channel flows that affect the state and level of safety of the hydraulic structures; – integrated use and protection of water bodies – water sources and water sources of water resources used in land reclamation; – development of measures and technical solutions for the protection of objects from the negative effects of water; – theoretical substantiation of works to improve the safety level of the GTS (declaration); – development and implementation of digitalization methods for solving design, construction, operation and control of landreclamation facilities. Currently, promising areas of research is the development of a decision-making algorithm in the designation of measures to rationalize the provision of resources to water amelioration. The algorithm is developed on the basis of a detailed study, systematization and processing of data both on safety and on the efficiency of systems and structures, ensuring the delivery of irrigation water of the required quality and in sufficient quantity from a water source to the field.

OCCURRENCE OF THE RISKS FOR DEVELOPMENT OF RESPIRATORY DISEASES IN CHILDREN EXPOSED TO THE CHEMICAL FACTORS OF THE EXPOSURE OF ALUMINA REFINERY- ASSOCIATED BUSINESS ACTIVITY

2019 ◽  
pp. 42-47 ◽  
Author(s):  
M.A. Zemlianova ◽  
I.V. Tikhonova
Keyword(s):  
Respiratory Tract ◽  
Respiratory Diseases ◽  
Inflammatory Diseases ◽  
Allergic Inflammation ◽  
Respiratory Morbidity ◽  
Upper Respiratory Tract ◽  
Negative Effects ◽  
Wide Range ◽  
Chemical Factors ◽  
Chronic Lymphoproliferative Diseases

Alumina refineries are among the leading sources of atmospheric air pollution with a wide range of pollutants hazardous to human respiratory organs. It is relevant to study and evaluate the occurrence of the risks for development of respiratory diseases in children living in the area affected by the emission components of an alumina refinery. We assessed air quality of the area under observation and comparison according to monitoring observations, risk of non-carcinogenic effects from the respiratory organs. The content of chemicals in the blood and urine adequate to risk factors was quantified. The structure of individual groups of respiratory diseases was analyzed. The causal relationships of violations of laboratory parameters with an increased content of chemicals in biological media were evaluated. It was found that an aerogenic exposure of chemical pollutants is formed on the territory with the production of metallurgical alumina. It determines the risk for development of respiratory diseases, exceeding an acceptable level up to 49.9 times. In the exposed children, the content of manganese, chromium, nickel, copper, xylenes, formaldehyde and aluminum, fluoride ion in the urine was increased to 4.2 times in relation to the indices in the comparison group. A high level of additional respiratory morbidity(1.8 times) was revealed. Chronic lymphoproliferative diseases of the nasopharynx and inflammatory diseases of the upper respiratory tract (up to 6.6 times more often), inflammatory diseases with a predominance of the mechanism of allergic inflammation ( up to 2.1 times more often)are more often detected in the framework of the respiratory diseases. Negative effects on the part of the respiratory system in the form of activation of antioxidant processes, the development of an inflammatory reaction, local, general and specific sensitization of the respiratory tract were established. It confirms the occurrence of the risks for the development of respiratory diseases in children in the exposure area of the chemical factors of alumina refinery-associated economic activity.

scholarly journals Isolation and Optimization of Culture Conditions of Thraustochytrium kinnei for Biomass Production, Nanoparticle Synthesis, Antioxidant and Antimicrobial Activities

2021 ◽  
Vol 9 (6) ◽  
pp. 678
Author(s):  
Kaliyamoorthy Kalidasan ◽  
Nabikhan Asmathunisha ◽  
Venugopal Gomathi ◽  
Laurent Dufossé ◽  
Kandasamy Kathiresan
Keyword(s):  
Antimicrobial Activity ◽  
Gold Nanoparticles ◽  
Silver Nanoparticles ◽  
Biomass Production ◽  
Petroleum Ether Extract ◽  
Antimicrobial Activities ◽  
Culture Conditions ◽  
Gold And Silver Nanoparticles ◽  
Optimization Of Culture Conditions ◽  
Antioxidant And Antimicrobial Activities

This work deals with the identification of a predominant thraustochytrid strain, the optimization of culture conditions, the synthesis of nanoparticles, and the evaluation of antioxidant and antimicrobial activities in biomass extracts and nanoparticles. Thraustochytrium kinnei was identified as a predominant strain from decomposing mangrove leaves, and its culture conditions were optimized for maximum biomass production of 13.53 g·L−1, with total lipids of 41.33% and DHA of 39.16% of total fatty acids. Furthermore, the strain was shown to synthesize gold and silver nanoparticles in the size ranges of 10–85 nm and 5–90 nm, respectively. Silver nanoparticles exhibited higher total antioxidant and DPPH activities than gold nanoparticles and methanol extract of the strain. The silver nanoparticles showed higher antimicrobial activity than gold nanoparticles and petroleum ether extract of the strain. Thus, Thraustochytrium kinnei is proven to be promising for synthesis of silver nanoparticles with high antioxidant and antimicrobial activity.

scholarly journals The Antimicrobial and Anti-Inflammatory Effects of Silver Nanoparticles Synthesised from Cotyledon orbiculata Aqueous Extract

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1343
Author(s):  
Caroline Tyavambiza ◽  
Abdulrahman Mohammed Elbagory ◽  
Abram Madimabe Madiehe ◽  
Mervin Meyer ◽  
Samantha Meyer
Keyword(s):  
Staphylococcus Aureus ◽  
Silver Nanoparticles ◽  
Metallic Nanoparticles ◽  
Methicillin Resistance ◽  
Antimicrobial Activities ◽  
Transmission Electron ◽  
Anti Inflammatory ◽  
Anti Inflammation ◽  
Important Medicinal Plant ◽  
Pro Inflammatory Cytokines

Cotyledon orbiculata, commonly known as pig’s ear, is an important medicinal plant of South Africa. It is used in traditional medicine to treat many ailments, including skin eruptions, abscesses, inflammation, boils and acne. Many plants have been used to synthesize metallic nanoparticles, particularly silver nanoparticles (AgNPs). However, the synthesis of AgNPs from C. orbiculata has never been reported before. The aim of this study was to synthesize AgNPs using C. orbiculata and evaluate their antimicrobial and immunomodulatory properties. AgNPs were synthesized and characterized using Ultraviolet-Visible Spectroscopy (UV-Vis), Dynamic Light Scattering (DLS) and High-Resolution Transmission Electron Microscopy (HR-TEM). The antimicrobial activities of the nanoparticles against skin pathogens (Staphylococcus aureus, Staphylococcus epidermidis, Methicillin Resistance Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans) as well as their effects on cytokine production in macrophages (differentiated from THP-1 cells) were evaluated. The AgNPs from C. orbiculata exhibited antimicrobial activity, with the highest activity observed against P. aeruginosa (5 µg/mL). The AgNPs also showed anti-inflammatory activity by inhibiting the secretion of pro-inflammatory cytokines (TNF-alpha, IL-6 and IL-1 beta) in lipopolysaccharide-treated macrophages. This concludes that the AgNPs produced from C. orbiculata possess antimicrobial and anti-inflammation properties.

scholarly journals Responses to Ecopollutants and Pathogenization Risks of Saprotrophic Rhodococcus Species

Pathogens ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 974
Author(s):  
Irina B. Ivshina ◽  
Maria S. Kuyukina ◽  
Anastasiia V. Krivoruchko ◽  
Elena A. Tyumina
Keyword(s):  
Survival Strategies ◽  
Complex Life Cycle ◽  
Anthropogenic Pressure ◽  
Resting Cells ◽  
Organic Substrates ◽  
Negative Effects ◽  
Anthropogenic Pollutants ◽  
Rhodococcus Species ◽  
Wide Range ◽  
Rigid Cell Wall

Under conditions of increasing environmental pollution, true saprophytes are capable of changing their survival strategies and demonstrating certain pathogenicity factors. Actinobacteria of the genus Rhodococcus, typical soil and aquatic biotope inhabitants, are characterized by high ecological plasticity and a wide range of oxidized organic substrates, including hydrocarbons and their derivatives. Their cell adaptations, such as the ability of adhering and colonizing surfaces, a complex life cycle, formation of resting cells and capsule-like structures, diauxotrophy, and a rigid cell wall, developed against the negative effects of anthropogenic pollutants are discussed and the risks of possible pathogenization of free-living saprotrophic Rhodococcus species are proposed. Due to universal adaptation features, Rhodococcus species are among the candidates, if further anthropogenic pressure increases, to move into the group of potentially pathogenic organisms with “unprofessional” parasitism, and to join an expanding list of infectious agents as facultative or occasional parasites.

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