TOXICITY ASSESSMENT OF ENGINEERED NANOPARTICLES USING ALGAE CHLORELLA VULGARIS

2017 ◽  
pp. 50-54
Author(s):  
A. A. Asanova ◽  
V. I. Polonskiy ◽  
Y. S. Grigoriev
Keyword(s):  
Chlorella Vulgaris ◽  
Photosynthetic Activity ◽  
Photosynthetic Apparatus ◽  
Test Organism ◽  
Toxicity Assessment ◽  
Delayed Fluorescence ◽  
Engineered Nanoparticles ◽  
Environmental Objects ◽  
Test Culture ◽  
Potential Risks

The use of nanoparticles covers new spheres of production every year. Their release into the environment is possible at any stage of their lifespan: from the manufacturing process to the utilization in the final product; therefore potential risks they pose for various environmental objects should be evaluated. The purpose of this work was to assess the effect of technogenic nanoparticles on Chlorella vulgaris growth and photosynthetic activity. Toxic properties of three types of nanoparticles TiO2 with a size of 100 to 190 nm, SiO2 with dimensions of 10-15 nm and 100-120 nm have been studied. Chlorella vulgaris Beijer alga was used as test organism. The evaluation of nanoparticles toxicity was based on changes in the relative delayed fluorescence index (RDFI), which characterizes the photosynthetic activity of microalgae. The effect on the growth of the test culture was determined from the optical density (OD) of the algal suspension. It was found that the TiO2 nanoparticles slightly reduced the growth and activity of the cell photosynthetic apparatus. Large particles of SiO2 proved to be more toxic than smaller ones. For nanoparticles of 100-120 nm size , the EC50 value according to the OD index was 8 mg/dm3, while the particles measuring 10-15 nm did not show a significant effect on the growth of the culture. Large SiO2 particles also appeared more toxic than small particles, judging by RDFI parameter.

scholarly journals Improvement of the photosynthetic activity of Moldavian dragonhead (Dracocephalum moldavica L.) through foliar application of a nitrophenolate–based biostimulant

2018 ◽  
Vol 10 ◽  
pp. 01009
Author(s):  
Sławomir Kocira ◽  
Agnieszka Sujak ◽  
Tomasz Oniszczuk ◽  
Agnieszka Szparaga ◽  
Mariusz Szymanek ◽  
...  
Keyword(s):  
Chlorophyll Content ◽  
Photosynthetic Activity ◽  
Foliar Application ◽  
Positive Impact ◽  
Abiotic Stress Tolerance ◽  
Photosynthetic Apparatus ◽  
Nutrient Content ◽  
Physiological Processes ◽  
Naturally Occurring ◽  
Reported Study

Application of biostimulants instigates many physiological processes that enhance nutrition efficiency, abiotic stress tolerance, and quality traits of crops, regardless of their nutrient content. One of such preparations is Atonik which contains nitrophenol compounds naturally occurring in plant cells. Several studies have confirmed its beneficial effect on the growth, development, and improved metabolic activity of plants. Therefore, it seems advisable to investigate the effect of Atonik preparation on the photosynthetic activity of Moldavian dragonhead (Dracocephalum moldavica L.). The reported study was carried out in 2014 in Perespa, Poland. Over the growing season, Atonik was foliar-applied at a dose of 0.3 L/ha (0.1%) and 0.6 L/ha (0.2%) by single and double spraying of plants. Chlorophyll content and nitrogen status (N) were estimated by a Chlorophyll Meter SPAD-502 Plus. The foliar application of Atonik was found to improve the efficiency of the photosynthetic apparatus and chlorophyll content in the leaves of Dracocephalum moldavica plants, but the results were dependent on biostimulant concentration and number of its applications, and on the date of measurement. To conclude, Atonik is an environmental-friendly preparation which has a positive impact on the metabolic processes of plants.

scholarly journals New insight into artifactual phenomena during in vitro toxicity assessment of engineered nanoparticles: Study of TNF-α adsorption on alumina oxide nanoparticle

2013 ◽  
Vol 27 (3) ◽  
pp. 1049-1056 ◽  
Author(s):  
Mélanie Pailleux ◽  
Delphine Boudard ◽  
Jérémie Pourchez ◽  
Valérie Forest ◽  
Philippe Grosseau ◽  
...  
Keyword(s):  
Toxicity Assessment ◽  
Engineered Nanoparticles ◽  
In Vitro Toxicity ◽  
Tnf Α ◽  
Alumina Oxide ◽  
Oxide Nanoparticle ◽  
In Vitro Toxicity Assessment ◽  
Insight Into

Hill-Activity and P700 Concentration of Chloroplasts Isolated from Radish Seedlings Treated with -Indoleacetic Acid, Kinetin or Gibberellic Acid

1977 ◽  
Vol 32 (9-10) ◽  
pp. 798-802 ◽  
Author(s):  
Claus Buschmann ◽  
Hartmut K. Lichtenthaler
Keyword(s):  
Steady State ◽  
Gibberellic Acid ◽  
Photosynthetic Activity ◽  
Indoleacetic Acid ◽  
Photosynthetic Apparatus ◽  
Promotion Effect ◽  
Hill Activity ◽  
The Hill ◽  
Radish Seedlings ◽  
Very High

Abstract The Hill-activity (reduction of DCPIP or methylviologen) and the concentration of P700 were studied in chloroplasts isolated from cotyledons of radish seedlings (R aphanus sativu s L. Saxa Treib), which had been grown with the addition of β-indoleacetic acid (IAA), kinetin, or gibberellic acid.1) The photosynthetic activity of young chloroplasts from 3 day old Raphanus seedlings is very high (c. 180 μmol O2/mol chlorophyll × h) and decreases continuously thereafter with increasing age. The steady state Hill-activity is readied after 8 to 10 days (values of 55 to 50 μmol 02/mg chlorophyll × h).2) Chloroplasts from plants treated with IAA or kinetin not only exhibit higher plastoquinone levels 1,2, but also a higher P700-content and a higher Hill-activity. The promotion effect is more pronounced with kinetin (+ 36 to 40%) than with IAA (+ 12 to 17%).3) Gibberellic acid has a different effect on composition and activity of chloroplasts. In younger seedlings the Hill-activity appears to be somewhat stimulated, without promotion effect on plasto­ quinone 2 or P700 concentration. After 10 days GA3-treated plants show signs of chlorosis combined with a strong decrease in photosynthetic activity.4) The data clearly demonstrate that the composition and activity of the photosynthetic ap­ paratus are under phytohormone control. IAA and even better kinetin promote the light induced formation of pigment systems and electrontransport chains. GA3 seems to block the rebuilding of the photosynthetic apparatus under steady state conditions.

Silver Nanoparticles: Transport and Fate in the Environment

2018 ◽  
Vol 2 (08) ◽  
Author(s):  
Kayla Dean ◽  
Felicia Jefferson
Keyword(s):  
Silver Nanoparticles ◽  
Consumer Products ◽  
Engineered Nanoparticles ◽  
Practical Application ◽  
Potential Toxicity ◽  
Current State ◽  
History Analysis ◽  
Potential Risks ◽  
Analytical Tools ◽  
The Impact

Within the previous few years major advances in the development of nanotechnologies and practical application of artificial nanoparticles (NPs) and nanomaterials (NMs) have resulted. As society becomes further aware that the use of nanomaterials is ever growing in consumer products and their presence in the environment, critical interest on the impact of this emerging technology has grown. A major concern is whether the unknown risks of engineered nanoparticles, in particular, their impact on health and environment, outweighs their established benefits to society. The goal is to evaluate their potential toxicity in the environment. Silver nanoparticles exhibit an important effect on microbial processes in environmental exposures. This study provides a brief review over the current state-of-knowledge about AgNPs from various studies in this area, including the history, analysis, source, transport, fate, and potential risks of AgNPs. In order to fully investigate the transport and fate of AgNPs in the environment, appropriate methods for the pre-concentration, separation, and speciation of AgNPs should be developed, and analytical tools for the characterization and detection of AgNPs in complicated environmental studies must be incorporated.

2-Alkylsulphanyl-4-pyridinecarbothioamides — inhibitors of oxygen evolution in freshwater alga Chlorella vulgaris

2011 ◽  
Vol 65 (6) ◽  
Author(s):  
Katarína Kráľová ◽  
František Šeršeň ◽  
Věra Klimešová ◽  
Karel Waisser
Keyword(s):  
Oxygen Evolution ◽  
Chlorella Vulgaris ◽  
Alkyl Chain ◽  
Photosynthetic Apparatus ◽  
Photosynthetic Electron Transport ◽  
Donor Side ◽  
Active Inhibitor ◽  
Oxygen Evolution Rate ◽  
Tyrosine Radical ◽  
D2 Protein

AbstractThe inhibition of the oxygen evolution rate (OER) in Chlorella vulgaris by 2-alkylsulphanyl-4-pyridinecarbothioamides (APCTs; alkyl = methyl up to hexadecyl) was studied. APCTs were found to inhibit photosynthetic electron transport (PET) which resulted in the inhibition of OER in algae. The inhibitory activity of APCTs was highly dependent on the alkyl chain length of the 2-alkylsulphanyl substituent and the corresponding dependence showed a bilinear course with the decyl derivative as being the most active inhibitor. Using EPR spectroscopy, the site of APCT action in the algal photosynthetic apparatus was determined. It was confirmed that APCT interacted mainly with the D. intermediate, i.e. with tyrosine radical (TyrD) occurring at the 161st position in D2 protein which is situated on the donor side of photosystem 2.

scholarly journals Misurare la vitalità delle piante per mezzo della fluorescenza della clorofilla

2012 ◽  
Author(s):  
Filippo Bussotti ◽  
Mohamed Hazem Kalaji ◽  
Rosanna Desotgiu ◽  
Martina Pollastrini ◽  
Tadeusz Loboda ◽  
...  
Keyword(s):  
Chlorophyll Fluorescence ◽  
Fluorescence Imaging ◽  
Low Temperatures ◽  
Photosynthetic Apparatus ◽  
Delayed Fluorescence ◽  
Chlorophyll Fluorescence Imaging ◽  
Strong Light ◽  
Fluorescence Techniques ◽  
Modulated Fluorescence ◽  
High And Low Temperatures

The book begins with a detailed description of the characteristics of the photosynthetic apparatus and the processes that take place there, to then present the general principles of fluorescence. After that, it gives a description of the characteristics of direct and modulated fluorescence and a presentation of the shared and distinctive parameters of these two techniques. Then a brief presentation is made of other innovative approaches to the analysis of fluorescence (Chlorophyll Fluorescence Imaging - CFI, P700 absorbance, delayed fluorescence) and the relative tools. An important part of the book comprises a description of the possible applications of fluorescence techniques for the analysis of various types of stress (aridity, strong light radiations, UV, high and low temperatures, salinity, weedkillers, pollution, etc.) and, consequently, their possible use in agriculture, forestry and to protect the environment.

Sign in / Sign up

Export Citation Format

Share Document