Procedimento lab

Journal of Arid Environments, 1995

Minor and trace elements of biological interest in some warm climate plants cultivated at Aswan (Egypt) were analysed to demonstrate their element metabolism, animal nutrition, toxicological effect and their uses as therapeutic plants. The seven plants studied were Macroptilium atropurpureum, Pennisetum glaucum, Cyamopsis tetragonolobus, Dolichos purpureus, Cajanus cajan 8 (Variety 78/237 A-Brasil), Cajanus cajan 13 (Variety 79/450 Uganda) and Prosopis juliflora. Silver, gold, cadmium, cobalt, copper, iron, potassium, manganese, magnesium, sodium, nickel, lead, strontium and zinc were analysed by an Atomic Absorption Spectrophotometer, while iodide, fluoride and chloride content were analysed using Ion Selective Electrodes. The results of analysis reveal that Prosopis juliflora exhibits the highest element concentration, which illustrates the high ability of this plant to concentrate these elements and also its highly nutritional value for animals, while all these plants can be used as therapeutic plants. All elements in the studied plants were in the safety baseline level for animals which reflect their nutritional and beneficial values. The present study gives a new picture about ion antagonism in these plants and their uses not only as a food for animals but also as therapeutic plants to compensate of element deficiency. Ion Selective Electrodes were used successfully and accurately for I, F and Cl measurements both by direct and known addition methods and in a low concentration measurement of these ions.

Division of Plant Physiology, IARI, New Delhi, 2017

Plant species, age, plant part and the time of sampling can affect the values of mineral nutrients present in a given sample. Besides this, the option used for the digestion of plant sample is also very important. So, for taking up the analysis of mineral nutrients in plant samples and getting the accurate and realistic results, proper and careful sampling and selection of digestion method are some of the very important considerations. Most of the essential elements are not equally distributed in the plant or within the plant parts. Although, it is possible to assay any plant part or even the whole plant but the biological significance of such an analysis always depends on the availability of interpretative data from the plant part(s) collected and used for the analysis. While conducting a plant analysis, primary objective should be to obtain the plant part for which assay results in actual comparison of plant samples coming from different types or stress treatments. Prior to elemental analysis, possible errors can occur at various stages such as; sample collection, initial handling, transportation, decontamination, drying, particle size reduction etc. Thus, possible sources of error must be known to the investigator for the accuracy of the whole procedure and the analysis. The sampling procedures and precautions required at various stages of sample preparation for the analysis of mineral nutrients are described here in this article.

Agrociencia

Las técnicas para analizar los elementos esenciales o tóxicos para las plantas y los seres humanos, ha experimentado un acelerado desarrollo en los últimos tiempos, tanto en las convencionales o clásicas, que requieren la solubilización de la muestra, como en otras emergentes que no la requieren. Las técnicas convencionales avanzadas y las no destructivas se usan poco por los investigadores en genética, agronomía, nutrición, fisiología, biología, para evaluar la composición y calidad nutrimental de alimentos, cuantificar elementos metálicos esenciales y tóxicos, diagnosticar el estado nutrimental de los cultivos y estudiar alimentos funcionales. Estas técnicas analíticas se pueden aplicar, además, a suelos, abonos y fertilizantes. El objetivo de este ensayo es difundir las posibilidades de aplicación y los principios básicos de estas técnicas analíticas emergentes. La espectrometría de emisión por atomización con plasma inductivamente acoplado (ICP, Inductively coupled plasma) y la ...

Canadian Journal of Forest Research, 1993

MINOCHA, R., and SHORTLE, W.C. 1993. Fast, safe, and reliable methods for extraction of major inorganic cations from small quantities of woody plant tissues. Can. J. For. Res. 23: 164551654, Two simple and fast methods for the extraction of major inorganic cations (Ca, Mg, Mn, K) from small quantities of stemwood and needles of woody plants were developed. A 3.2-or 6.4-mm cobalt drill bit was used to shave samples from disks and increment cores of stemwood. For ion extraction, wood (ground or shavings) or needles were either homogenzied using a Tekmar Tissumizer or frozen and thawed (three times) in 0.01 M HC1. After filtration through a 0.45-pm nylon filter, the extract was analyzed for ion content using direct current plasma atomic emission spectrometry. Quality control samples of pine needles obtained from the National Institute of Standards and Technology, and individually pooled wood samples of red spruce (Picea rubens Sarg.) and red oak (Quercus rubra L.), were used to compare these two methods of extraction with the most commonly used method of wet ash digestion. The results of either method of extraction (freezing-thawing or homogenization) were higher than or similar to those obtained by wet digestion. Direct use of drill shavings eliminates the need for making wood chips by hand and grinding in a Wiley mill. Moreover, both approaches are relatively safe, since they do not require the use of hot concentrated acids and strong oxidizing agents. These methods may be particularly useful for the analysis of major inorganic cations from extremely small size samples ) such as individual annual growth rings of mature trees. MINOCHA, R., et SHOKTLE, W.C. 1993. Fast, safe, and reliable methods for extraction of major inorganic cations from small quantities of woody plant tissues. Can. J. For. Res. 23 : 1645-1654. Deux mCthodes simples et rapides ont Ct C mises au point pour extraire les principaux cations inorganiques (Ca, Mg, Mn, K) ii partir de petites quantitCs de bois et d'aiguilles chez les plantes ligneuses. De la cisaille de bois a Ct C produite B partir de disques et de carottes B l'aide d'un foret au cobalt de 3,2 ou 6,4 mm. Pour l'extraction des cations, la mouture ou la cisaille de bois et les aiguilles ont Ct C soit homogCnCisCes ii l'aide d'un (~Tekmar Tissumizer>) ou congelCes et dCgelCes trois fois dans du HCl 0,01 M. Aprbs filtration avec une filtre de nylon de 0,45 pm, le contenu en ions des extraits a Ct C dCterminC directement par spectromCtrie dlCmission atomique B plasma ? i courant direct. Des Cchantillons d'aiguilles de pin, pour le contr6le de qualitC, obtenus du <(National Institute of Standards and Technology)) ainsi que des Cchantillons de bois d'Cpinette rouge (Picea rubens (Raf.) Sarg.) et de ch&ne rouge (Quercus rubra L.) regroupCs individuellemeut ont Ct C utilisCs pour comparer les deux mCthodes d'extraction avec la mCthode de digestion humide qui est la plus communCment utilisCe. Les rksultats de l'une ou l'autre des methodes d'extraction (gel-dCgel ou homogenCisation) Ctaient plus ClevCs ou semblables B ceux obtenus par digestion humide. L'utilisation directe de la cisaille de bois Climine la nCcessitC de produire des copeaux de bois B la main et de les broyer dans un broyeur Wiley. De plus, les deux approches sont relativement skcuritaires Ctant donnC qu'elles ne nkcessitent pas l'utilisation d'acides chauds et concentrCs et de puissants agents d'oxydation. Ces mCthodes peuvent &tre particulibrement utiles pour l'analyse des principaux cations inorganiques dans des Cchantillons de trbs petite dimension (25 mg) tels que les cernes annuels individuels chez les arbres matures.

Pakistan Journal of Chemistry, 2021

Chloride ion is an essential nutrient and important part of photosystem II of the plants, provide help in evolving oxygen from leaves of the plants to maintain atmospheric oxygen. This article explores the application of Mohr's method for the detection of chloride ions in aqueous extract of plants tissues using conductometric titration. For this purpose, two plants, Suaeda fruticose and Salvadorapersica, were selected, and their leaves were examined to detect the chloride ion. The leaves extract was prepared by crushing, boiling, depigmentation, filtration, centrifugation, and precipitation reaction with AgNO 3 .The application of this conductometric technique indicates the equivalence point in chemical precipitation titration of the plant's tissue extract with AgNO 3 , beneficial to determine the environmental impact related to the reduced growth rate. It was observed that results are approximately similar to those obtained by Mohr's method. It was observed that the developed method is quick, precise, and straightforward for determining the chloride concentration in plants. The chemical analytical testing for chloride ions confirms the detection and separation of said ions in plants tissues extract.

Sustainability

The question of trace metal elements (TME) is still relevant and causes several environmental problems. Moreover, the digestion methods of TME have a significant impact on ecosystems. Sample preparation is an important step of any analytical procedure. In fact, defining the levels of TME in vegetal tissues requires various steps: drying samples, crushing, extraction, and dosage. The use of chemical extraction solutions can be put into question. Other than their lack of specificity, they are susceptible to provoking the redistribution and/or re-fixation of a part of the metallic ions between the various vegetal components. Our study aims to test the procedures of extraction that are specific for the metals Cu, Zn, Fe, Ca, Cr and Ba. Our results show an outstanding difference in the levels of TME derived from the same vegetal sample, according to the various techniques of extraction. In fact, cold extraction by nitric acid diluted at 10% is the most efficient way to put the ions of Cu...

Environments

Trace elements (As, Cd, Cr, Pb, Ba, Fe, Al, Mn and Ba) were uptaken by the leaves of the creosote bush (Larrea tridentata (DC.) Coville) in Nelson, Nevada, although at low concentrations. Samples were collected up-gradient of the mine tailings, the tailings, and down gradient from the source to measure spatial distribution. Data show that trace elements (As, Ba, Cr, Hg, Se) enter L. tridentata through root tissues, migrating to leaf tissue, but at significantly lower levels than that of the source sediments. Metalloid (As and Se) concentrations in the leaf tissues ranged from non-detect to greater than 44 mg kg−1 As and non-detect to over 34 mg kg−1 Se. For trace metals, Hg ranged from non-detect to 0.14 mg kg−1; Ba from 1.74 to 4.12 mg kg−1; and Cr from non-detect to 6.18 mg kg−1 while Ag, Cd, and Pb were not detected in the plant leaves. When comparing the ratio of sediment metal concentration to plant metal concentrations, the Techatticup Wash contained the highest levels of trac...

Analytical Letters, 2018

This study investigated the accumulation of macro-, micro-, and toxic elements in Phaseolus vulgaris tissues, including pods, leaves, stems, and roots, as a function of the isotopic composition of irrigation water. The novelty of the paper consists of the simulation of environmental conditions by varying the isotopic content of the water to verify the applicability of obtained results in different climatic areas (i.e., tropical and temperate regions) and the association between highly sensitive analytical techniques and chemometric methods to extract the maximum information from the measurements along with the evaluation of the absorption and translocation of heavy metals by the various plant tissues. The use of tap water for irrigation of P. vulgaris increased the concentrations of chromium, manganese, cobalt, nickel, copper, zinc, and cadmium in the plants, especially in the stems and leaves. Cadmium accumulated in the leaves or stems but not in the pods. The roots and stems absorbed and accumulated cadmium using tropical water and deuterium-depleted water.

Environmental Monitoring and Assessment, 2006

Bioindicators are widely used in the study of trace elements inputs into the environment and great efforts have been conducted to separate atmospheric from soil borne inputs on biomass accumulation. Many monitoring studies of trace element pollution take into account the dust particles located in the plant surface plus the contents of the plant tissues. However, it is usually only the trace element content in the plant tissues that is relevant on plant health. Enrichment factor equations take into account the trace element enrichment of biomasses with respect soil or bedrocks by comparing the ratios of the trace element in question to a lithogenic element, usually Al. However, the enrichment equations currently in use are inadequate because they do not take into account the fact that Al (or whichever reference element) and the element in question may have different solubility-absorptionretention levels depending on the rock and soil types involved. This constrain will become critical when results from different sites are compared and so in this article we propose that the solubility factors of each element are taken into account in order to overcome this constrain. We analysed Sb, Co, Ni, Cr, Pb, Cd, Mn, V, Zn, Cu, As, Hg, and Al concentration in different zones of Catalonia (NE Spain) using the evergreen oak Quercus ilex and the moss Hypnum cupressiforme as target species. We compared the results obtained in rural and non industrial areas with those from the Barcelona Metropolitan Area. We observed differences in Al concentrations of soils and bedrocks at each different site, together with the differences in solubility between Al and the element in question, and a weak correlation between total soil content and water extract content through different sites for most trace elements. All these findings show the unsuitability of the current enrichment factors for calculating lithospheric and atmospheric contributions to trace element concentrations in biomass tissues. The trace element enrichment factors were calculated by subtracting the part predicted by substrate composition (deduced from water extracts from soils and bedrock) from total concentrations. Results showed that for most of the trace elements analysed, trace elements enrichment factors were higher inside the Barcelona Metropolitan Area than outside, a finding that indicates that greater atmospheric inputs occur in urban areas. The results show that the most useful and correct way of establishing a reference for lithospheric and atmospheric inputs into the plant tissues is, first, to analyse samples of the same plant species collected from a number of sites possessing similar environmental conditions (climate, vegetation type, soil type) and, second, to use this new enrichment factor obtained by subtracting from the total concentration in plant tissue the predicted contribution of soil or bedrock extracts instead of that of total soil or bedrock concentrations.

Nutrition & Food Science, 2009

Anthropogenic agronomic practices could negatively affect the agricultural soil which is the main source for inorganic arsenic (i-As) contamination in rice fields due to flooding. The presence of essential elements could be impacted by food industry units operations. The aim of this study was to evaluate the effect of husking and polishing on mineral essential elements and inorganic As species in rice from Protected Natural Reserve "Marjal de Pego-Oliva". The amount of all studied elements was significantly affected by husking (a decrease of Ca, Na and Pb, 360 to 101 mg kg − 1 , 202 to 46.9 mg kg-1 and 17.9 to 5.70 μg kg − 1 , respectively) and by polishing (a reduction of Na, Mg, P, K, Ca and Cu, 46.9-26.8 mg kg − 1 , 1600 to 481 mg kg − 1 , 4050 to 1530 mg kg − 1 , 2780 to 882 mg kg − 1 , 101 to 53.7 mg kg − 1 , and 3600 to 2840, μg kg − 1 , respectively).The replacement of white rice (WR) to brown rice (BR) could enhance the daily dietary intake of essential elements to reach the dietary reference values and the maximum i-As (40.9 and 44.9 i-As μg kg-1 for BR and WR, respectively) was below the maximum level recently established by European Food Safety Agency.