The toxicity of levofloxacin to yellow lupin plants was evaluated in this study. Recommended indexes of plant (roots and shoots) growth were determined and new indexes were proposed which better characterise the phytotoxicity of levofloxacin. These were, in particular, the activity of antioxidative enzymes, the content of free radicals, as well as the root protein content and the root protein profile. The results showed that levofloxacin considerably affected EC50, measured as the activity of catalase in roots, and leaves (1.05 and 0.069 mM, respectively). The activity of peroxidase in the roots and the dry weight of seedlings were the least sensitive parameters (EC50 was 1.8 and 1.76 mM, respectively). Units of toxicity clearly showed that the activity of catalase is a better measure of toxicity for low concentrations of the drug, and it is a better index of plant physiological state than the morphological parameters of seedlings. Moreover, levofloxacin changed the location of free radicals and the protein profile in plants. The changes in location of reactive oxygen species in roots were an important symptom of the drug toxicity to lupin seedlings. Our results have shown that the toxicity of levofloxacin was manifested mainly by changes in the protein profile. The content of the glyceraldehyde-3-phosphate dehydrogenase, 14-3-3-like protein A, expansin-B3-like precursor, fructose-bisphosphate aldolase, lipoxygenase, nucleotide-binding subunit of vacuolar ATPase and pyruvate dehydrogenase were found to decrease. On the other hand, plant exposure to levofloxacin resulted in an increase in the content of enolase, protein LlR18A, class III chitinase, ascorbate peroxidase, aspartate aminotransferase, alcohol dehydrogenase 1, leghemoglobin reductase-like 17 and heat shock cognate protein 80-like.
This review describes the role of silicon (Si) in plants. Methods of silicon determination and speciation are also reported. The mechanisms of Si uptake by plants, silicon fractions in the soil, and the participation of flora and fauna in the Si cycle in terrestrial ecosystems have been overviewed. Plants of Fabaceae (especially Pisum sativum L. and Medicago sativa L.) and Poaceae (particularly Triticum aestivum L.) families with different Si accumulation capabilities were taken into consideration to describe the role of Si in the alleviation of the negative effects of biotic and abiotic stresses. The article focuses on sample preparation, which includes extraction methods and analytical techniques. The methods of isolation and the characterization of the Si-based biologically active compounds from plants have been overviewed. The antimicrobial properties and cytotoxic effects of known bioactive compounds obtained from pea, alfalfa, and wheat were also described.
14 July 2022 in Polish Journal of Environmental Studies
Photosynthesis is one of the main processes involved in plant growth and development. This process is sensitive to environmental stressors, including cadmium environment contamination. Therefore, this study investigated, among other things, the effect of cadmium on the fluorescence of photosynthesis parameters, chlorophyll fluorescence; moreover, as the chlorophyll and carotenoids contents were measured. The toxic effect of cadmium on the growth, development, and photosynthesis process was confirmed. In order to study the cadmium binding mechanism by the plant, the first step was to verify the cadmium quantification method with ICP-Q-MS. It was shown that selecting the m/z spectral line: 114; gave a lower background and higher sensitivity for the determination of cadmium in a solution than when selecting 112. The limits of detection and quantification are 2.2 and 7.5 ng/L, respectively, and the method is linear in the investigated concentration range (range up to 100 μg/L). The method of the microwave assisted mineralization in the preparation of a plant sample was shown to meet the requirements of accuracy (recovery with the certified reference material 98%) and repeatability (0.13% in five repetitions). Root and shoot samples of pea were examined and the accumulation of cadmium especially in the roots was found, which proves the excludable properties of the plant.
12 July 2024 in Journal of Soil Science and Plant Nutrition
Purpose: The aim of this study was to investigate the role of silicon (Si) in counteracting a cadmium (Cd) stress to pea plants (Pisum sativum L.) and to identify the mechanism by which Cd is bound within pea roots. Methods: These goals were achieved through (i) a histochemical study of Cd localization in pea roots, (ii) spectrophotometric determination of pectin content and the activity of pectin methylesterase (PME), (iii) speciation of Cd extracted from pea roots conducted through size exclusion chromatography (SEC) and inductively coupled plasma mass spectrometry (ICP/MS). Results: Cd was found mainly in the root stele of the Cd-stressed plants. The pectin content and PME activity were lower in the Cd-stressed plants, but Si supplementation reversed these effects. Selectivity was noticed in Cd extraction efficiency with water being the least effective and enzymatic-assisted extraction proving to be the most effective. Speciation analysis revealed significant heterogeneity in molar mass, ranging from approximately 295 to 95 kDa. Galacturonic acid was identified the dominant species responsible for Cd binding. The choice of solvent for extraction markedly influenced the Cd binding profile, indicating shifts in the distribution of species’ molar mass and their relative concentrations in extracts. Conclusions: Si alleviates Cd toxicity in pea plants, and one of the mechanisms through which it operates involves increasing pectin levels and PME activity. Pectin plays an active role in Cd detoxification in the root cell walls, forming electrostatic bonds with Cd cations through its carboxyl groups.
Halophytes such as Salicornia europaea rely on biochemical and structural mechanisms to survive in saline environments. This study aimed to evaluate oxidative stress and structural defense responses in four inland populations—Poland (Inowrocław, Ciechocinek), Germany (Salzgraben-Salzdahlum, Salz), and Soltauquelle (Soltq)—subjected to 0, 200, 400, and 1000 mM NaCl, using non-destructive, image-based approaches. Lipid peroxidation was assessed via malondialdehyde (MDA) detected with Schiff’s reagent, and hydrogen peroxide (H2O2) accumulation was visualized with 3,3′-diaminobenzidine (DAB). Roots and shoots were analyzed through colour image analysis and quantified using a computer vision system (CVS). MDA accumulation revealed population-specific differences, with Salz tending to exhibit lower peroxidation, characterized by lower L* ≈ 42–43 and higher b* ≈ 37–18 in shoots at 200–400 mM, which may reflect a potentially more effective salt-management strategy. Although H2O2 responses deviated from a direct salinity-dependent trend, particularly in the tolerant Salz and Soltq populations, both approaches effectively tracked population-specific adaptation, with German populations displaying detectable basal H2O2 levels, consistent with its multifunctional signalling role in salt management and growth regulation. Structural defences were further explored through histochemical mapping and image analysis of pectin and lignin distribution, which revealed population-specific patterns consistent with cell wall remodelling under stress. Non-destructive, image-based methods proved effective for detecting oxidative and structural responses in halophytes. Such a non-destructive, cost-efficient, and reproducible approach can accelerate the identification of salt-tolerant ecotypes for saline agriculture and reinforce S. europaea as a model species for elucidating salt-tolerance mechanisms.
Krzem (Si) jest pierwiastkiem występującym w dużych ilościach w skorupie ziemskiej. Niektóre rośliny, takie jak pszenica pobierają Si z gleby i akumulują go w swoich tkankach w większych ilościach niż np. groch czy lucerna. Co ciekawe, suplementacja krzemem wpływa na zwiększenie plonu tych roślin. Ponadto, w wielu przypadkach Si niweluje negatywne skutki działania stresów biotycznych i abiotycznych, co wskazuje na uruchomienie w roślinach procesów, być może poprzez produkcję związków o charakterze regeneracyjnym lub obronnym. Z drugiej strony pszenica, groch i lucerna są roślinami o znanych właściwościach cytotoksycznych. Poszukiwanie związków bioaktywnych pochodzenia roślinnego o potencjalnie pozytywnym wpływie, jest zagadnieniem o dużym znaczeniu zarówno poznawczym jak i praktycznym, ze względu na możliwość wykorzystania takich związków w leczeniu wielu chorób człowieka. Prezentowana praca przedstawia aktualny stan wiedzy na temat pobierania, transportu oraz efektów suplementacji krzemem roślin poddawanych stresom biotycznym i abiotycznym oraz właściwości cytotoksycznych pszenicy, grochu i lucerny. Słowa kluczowe: krzem, pszenica, groch, lucerna, stresy biotyczne i abiotyczne, cytotoksyczność