Уточнить поиск
Результаты 1-5 из 5
Effects of polystyrene nanoplastics on lead toxicity in dandelion seedlings
2022
Increasing rates of commercialization and industrialization have led to the comprehensive evaluation of toxic effects of microplastics on crop plants. However, research on the impact of functionalized polystyrene nanoplastics on the toxicity of heavy metals remains limited. This study investigated the effects of polystyrene, carboxy-modified polystyrene, and amino-modified polystyrene on lead (Pb) toxicity in dandelion seedlings. The results showed that carboxy -modified polystyrene with a negative charge absorbed more Pb²⁺ than polystyrene and amino-modified polystyrene, and their maximum adsorption amounts were 5.328, 0.247, and 0.153 μg g⁻¹, respectively. The hydroponic experiment demonstrated that single amino-modified polystyrene was more toxic to dandelion seedlings than polystyrene and carboxy-modified polystyrene. The presence of Pb²⁺ was found to increase antioxidant enzymes (superoxide dismutase and catalase) and non-antioxidant enzymes (glutathione and ascorbic acid) activities in response to excessive reactive oxygen species in dandelion leaves and roots treated with polystyrene and carboxy-modified polystyrene, while it did not change much when amino-modified polystyrene was added. Interestingly, compared with single Pb²⁺, the addition of amino-modified polystyrene with positive charges induced an obvious decrease in the above parameters; however, they declined slightly in the treatments with polystyrene and carboxy-modified polystyrene despite a stronger adsorption capacity for Pb²⁺. Similarly, the bioactive compounds, including flavonoids, polyphenols, and polysaccharides in dandelion, showed a scavenging effect on O₂⁻ and H₂O₂, thereby inhibiting the accumulation and reducing medicinal properties. This study found that the effects of microplastics on the uptake, distribution, and toxicity of heavy metals depended on the nanoparticle surface charge.
Показать больше [+] Меньше [-]Dandelion Taraxacum linearisquameum does not reflect soil metal content in urban localities
2016
Kováčik, Jozef | Dudáš, Matej | Hedbavny, Josef | Mártonfi, Pavol
Accumulation of selected heavy metals (Cd, Pb, Ni, Cr, Fe, and Zn) and phenolic metabolites (total soluble phenols, cichoric and caftaric acid) in dandelion organs (leaves, roots, inflorescences/anthodia) collected from six localities within the industrial town Košice (eastern Slovakia) were studied. Localities from the vicinity of a steel factory (Cd, Fe) and heavy traffic (Pb, Ni, Cr, Zn) contained the highest amount of individual metals in the soil but a significant correlation between soil and organ metal content was found only for Cr in the leaves (r2 = 0.7679). The amount of Cd and partially Pb differed among localities in all organs and especially in the leaves and anthodia, indicating probably the impact of atmospheric pollution. The bioaccumulation factor was <1 for almost all metals, suggesting that given dandelion species is not metal accumulator. Translocation factor did not reach values close to or over 1 only for Cd, indicating a root-to-shoot movement of Pb, Ni and Zn though the impact of air pollution on leaves cannot be excluded. A strong correlation between leaf Cd and leaf total phenols, cichoric and caftaric acids was observed (r2 = 0.7926, 0.8682 and 0.8830, respectively), indicating that phenolic metabolites act in the protection of dandelion against Cd excess. Overall, our data indicate low pollution of urban soil by Cd (5.53–113.8 ng g−1) and partially by Cr and the suitability of above-ground organs of dandelion species for the monitoring of air pollution mainly by Cd.
Показать больше [+] Меньше [-]Effects of ozone on managed pasture: II. Yield, species composition, canopy structure, and forage quality
1994
Fuhrer, J. | Shariat-Madari, H. | Perler, R. | Tschannen, W. | Grub, A. (Swiss Federal Research Station for Agricultural Chemistry and Environmental Hygiene, CH-3097 Liebefeld-Bern (Switzerland))
Sustainable application of novel herbs on cotton fabrics as biomordants and colourants
2022
Thakker, Alka Madhukar | Sun, Danmei
The textile industry is ambitiously parading towards circularity and curtailing its dependency on fossil fuels hence the instigated research that adheres to Sustainable Developmental Goals (SDGs) and benefits the environment and human health alike. The current research experimented with innovative sources of plant-based biomaterials namely dandelion leaves, bilberry leaves, nettle leaves, and violet herb for application on cotton fabric as biomordants and colourants. The AAS analysis of mild 6% herbal solution revealed ferrous content of 6.78 mg/l in violet herb and 5.03 mg/l of the copper content in dandelion leaves applicable on cotton fabrics as biomordants thereby preventing the depletion of copper and ferrous elements mineral ores. A fair lightfastness rating and good to very good wash and rub fastness test results were obtained individually. The maximum K/S value of 13.95 was gained on cotton fabrics treated with a mild herbal infusion of bilberry leaves and coloured with violet herbs. The ATR-FTIR peak analysis noted strong = C-H bend of alkenes, strong C = O stretch of α and β unsaturated esters, and strong C-O stretch of carboxylic acids functional groups in raw herbs and its treated cotton fabrics. The dissolved oxygen (DO), oxidation–reduction potential (ORP), and potential of Hydrogen (pH) values were found in the acceptable range for all the spent solutions left after colouration of cotton fabrics with violet herbs hence sustainable. The data set obtained was statistically validated with ANOVA one-way test. Life cycle analysis and clinical investigation on potential therapeutic benefits of herbal fabrics to the wearer are suggested for future research and development.
Показать больше [+] Меньше [-]Metal contamination in urban street sediment in Pisa (Italy) can affect the production of antioxidant metabolites in Taraxacum officinale Weber
2014
Bretzel, Francesca | Benvenuti, Stefano | Pistelli, Laura
Taraxacum officinale Weber (dandelion) is a very ubiquitous species, and it can grow in urban environments on metal-polluted sediments deposited in the gutters. This study represents a preliminary step to verify the presence of metals in sediments collected in urban streets in Pisa and to assess the alteration in dandelion metabolites in order to understand its adaptation to polluted environments. The soil and sediments were collected at three urban streets and analyzed for total and extractable Cr, Pb, Cu, Ni, and Zn. The total values of Pb and Zn in street sediments exceeded the limits for residential areas of soils. Zn was the most mobile of the metals analyzed. Floating cultivations trials were set up with dandelion seedlings and street sediments. The metals were analyzed in roots and leaves. Antioxidant power, anthocyanins, polyphenols, non-protein thiols (NP-TH) and chlorophylls were measured in dandelion leaves. The first two parameters (anthocyanins and antioxidant power) were higher in the polluted samples compared to the control; chlorophyll content was lower in the treated samples, whereas NP-TH showed no differences. NP-TH groups determined in roots were associated with the root content of Zn and Pb. These results indicate that dandelion can tolerate plant stress by altering its metabolite content.
Показать больше [+] Меньше [-]