Effects of various dry ashing temperatures on the determination of 13 nutrient elements in five plant tissues

Until recently it has been generally assumed that Ge taken up by plants is stored in phytoliths together with Si. This assumption is mostly based on the geochemical similarities between Ge and Si, while a scientific proof was lacking. The aim of the present study is to&#160;i) compare&#160;the uptake of Si and Ge in three grass species, ii) localize Ge and Si stored in above-ground plant parts and iii) evaluate the amounts of Ge and Si sequestrated in phytoliths and plant tissues. Mays (Zea mays), oat (Avana sativa) and reed canary grass (Phalaris arundinacea) were cultivated in the greenhouse on soil and sand to control element supply. Leaf phytoliths were extracted by dry ashing. Total elemental composition of leaves, phytoliths, stems and roots were measured by ICP-MS. For the&#160;localization of phytoliths and&#160;the determination of Ge and Si within leaf tissues and phytoliths scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX) and laser ablation ICP-MS (LA-ICP-MS) was used. The amounts of Si and Ge taken up by the species corresponded with biomass formation and decreased in the order Z. mays >P. arundinacea, A. sativa. Results from LA-ICP-MS revealed that Si was mostly localizedin phytoliths, while Ge was disorderly distributed within the leaf tissue. In fact, from the total amounts of Ge accumulated in leaves only 10% was present in phytoliths highlighting the role of organic Ge species in plant tissues and the necessity for using bulk Ge/Si instead of Ge/Si in phytoliths to trace biogeochemical cycling of Si. Moreover, our results represent important background data for the optimization of a phytomining of Ge.

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Foodstuffs. Determination of trace elements. Determination of total arsenic by hydride generation atomic absorption spectrometry (HGAAS) after dry ashing

10.3403/03269584u ◽

2015 ◽

Keyword(s):

Trace Elements ◽

Atomic Absorption Spectrometry ◽

Atomic Absorption ◽

Hydride Generation ◽

Absorption Spectrometry ◽

Total Arsenic ◽

Dry Ashing

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An HPLC-automated Derivatization for Glutathione and Related Thiols Analysis in Brassica rapa L.

Agronomy ◽

10.3390/agronomy11061157 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1157

Author(s):

Francesco Nacca ◽

Concetta Cozzolino ◽

Petronia Carillo ◽

Pasqualina Woodrow ◽

Amodio Fuggi ◽

...

Keyword(s):

Brassica Rapa ◽

High Performance ◽

Internal Standard ◽

Plant Tissues ◽

Cellular Functions ◽

Sulphur Compounds ◽

Stress Protection ◽

Automated Method ◽

Reduced Forms

The high content of glucosinolates and glutathione makes the Brassicaceae an important healthy food. Thiols and especially glutathione and γ-Glu-Cys-Gly tripeptide are involved in many fundamental cellular functions such as oxidative stress protection. Although several methods for sulphur compounds analysis in biological samples are actually used, the determination of glutathione and other sulphur derivatives in plant tissues is rather problematic due to their extreme susceptibility to oxidation, which can lead to their overestimation. The aim of this work was the improvement and validation of an automated method for determination of reduced and oxidised glutathione, cysteine and γ-glutamylcysteine in plant tissues. The method consists of a fully automated pre-column derivatization of thiols based on monobromobimane reagent, a high-performance liquid chromatography derivatives separation, and a fluorimetric detection and quantification. The method was successfully applied for determination of the oxidized and reduced forms of Cys, γ-GC and GSH content in leaves, petioles, inflorescences and roots of Brassica rapa L. subsp. Sylvestris. At harvest, in freshly cut plants, the average contents of GSH/2GSSG were 840/45, 345/70 and 150/70 nmol g−1 FW for the florets, leaf blades and stems, respectively; those of Cys/2Cys were 80/12, 29/12 and 24/6 nmol g-1 FW; while those of γ-GC/γ-GCCG-γ were 8.0/4.0, and 6.0/3.0, 3.0/2.0 nmol g−1 FW, respectively. Such amounts were lower in low-sulphur-grown plants at harvest. The very low coefficient of variation between repeated tests (maximum 1.6%), the high recovery of internal standard (>96%) and the linear correlation coefficient of the calibration (R2 > 0.99) support the efficiency of this method that allowed analysing about 50 samples/die in a totally automated manner with no operator intervention. Our results show that the reported method integrations can significantly improve thiols detection via HPLC.

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Effects of Macronutrients in the Physiological Quality of Soybean Seeds

Journal of Agricultural Science ◽

10.5539/jas.v10n5p312 ◽

2018 ◽

Vol 10 (5) ◽

pp. 312

Author(s):

Geliandro Anhaia Rigo ◽

Luis Osmar Braga Schuch ◽

Willian Silva Barros ◽

Rodrigo Lamaison de Vargas ◽

Vinícius Jardel Szareski ◽

...

Keyword(s):

Graduate Program ◽

Plant Tissues ◽

Soybean Seeds ◽

Rio Grande Do Sul ◽

Genetic Characteristics ◽

Physiological Quality ◽

High Concentrations ◽

Nitrogen Phosphorus

The aim of this work was to correlate macronutrient content of soybean seeds to physiological quality of different cultivars. The work was developed in the Federal University of Pelotas, in the facilities of the Seed Science and Technology Graduate Program. The experimental design was randomized blocks in arranged in four replicates. The following soybean cultivars were used: BMX Apolo RR (12 lots), BMX Ativa RR (13 lots), BMX Energia RR (26 lots), BMX Força RR (24 lots), BMX Impacto RR (35 lots), BMX Magna RR (16 lots), BMX Turbo RR (44 lots), BMX Potência RR (82 lots) and NA 5909 RR (28 lots), with seeds produced in northwest Rio Grande do Sul. The determination of nutritional contents found in plant tissues of soybean seeds, were measured: Nitrogen (N), Phosphorus (P), Potassium (K), Magnesium (Mg), Calcium (Ca), Sulfur (S). The macronutrient contents of the seeds vary according to genetic characteristics of the cultivars, with higher oscillations of nitrogen, phosphorus, magnesium and sulfur contents present in soybean seeds. Potassium and calcium are defined as the most stable nutrients for the cultivars and seed lots analyzed. High concentrations of nitrogen, phosphorus and calcium are determinants for the physiological quality of soybean seeds.

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