Samples Of Plant Material Research Articles

Sampling of plant material for chemical analysis

The term “green nanotechnology” can be employed to explain the use of biological sources and biological activity and specificity for the development of modern technology at the nanoscale. Indeed, the parallel development of nanotechnology with green chemistry methods, and the potential synergies between the two fields, can facilitate sustainable methods leading to reduced environmental impacts, improved conservation, and the protection of resources and human health. Increased awareness of green chemistry and biological processes has led to the necessity to develop environmentally friendly techniques for the production of nontoxic and biocompatible nanoparticles. The main methods for nanoparticle production utilize chemical and physical approaches that are often costly and potentially harmful to the environment. This chapter is devoted to the possibility of metal nanoparticle synthesis using biological sources, such as plants and microorganisms. The low toxicity of green synthesized nanoparticles is a significant parameter that is highly studied using plants and microorganisms, such as fungi, bacteria, viruses, yeasts, enzymes, etc., as bioreducing, stabilizing, and capping agents.

Sampling of plant material for chemical analysis

Sampling procedure and plant parts which are sampled strongly depend on the scope of the investigation. In contrast to sampling of abiotic components trace element concentrations of plant materials are strongly dependent on plant age, organ and tissue function, genotypic character of uptake, translocation and allocation, and are modified by the impact of other organisms. The consequences of these dynamic processes are considerable differences in element matrices. After the identification of the individual in the field the aim of the investigation will decide on the plant part(s) to be sampled, either at random or selectively. The most frequently taken plant parts in space and time are the leaves, either deciduous or evergreen. Leaf age, their position and insertion on the plant, their longevity, infestations by pathogens, injury by herbivores, and exposure to atmospheric components determine the element concentration; therefore a rigid sampling protocol is necessary. Due to their different chemical compositions, twigs and stems have to be separated into bark inclusive of phloem and wood. Exposure to precipitation and colonisation by epiphytes and bark decomposers have to be noted. In the case of roots, many chemical elements are only adsorbed to the root cell walls and are not, or only to very low degree, translocated to the other root cell components and from roots to shoots. In addition to high fragility of fine roots and root hairs and their strong association with soil particles and soil organic matter, roots of most plant species have an intimate symbiotic association with mycorrhizal fungi. The change in the degree of infestation with endomycorrhizal fungi during one growing season and the change of ectomycorrhizal partners during life history are important aspects of sampling for monitoring purposes. The great variation of rooting depth during ontogeny, dependent on soil conditions, requires control of this parameter in the field. A protocol for random and selected sampling will be presented.

Rapid Multiresidue Screen for Alkaloids in Plant Material and Biological Samples

A multiresidue screen for the quantitative and qualitative determination of alkaloids in plant material, animal ingesta, tissue, and biological fluid is described. The alkaloids were extracted with 5% ethanol in ethyl acetate (v/v) after the addition of aqueous NaOH. The organic extract was cleaned up by partitioning with 0.5 N HCl. The aqueous phase was made alkaline; the alkaloids were retained on a polymeric C-18 minicolumn and subsequently eluted with ethyl acetate. The concentrated extract was analyzed quantitatively by GC/NPD. The alkaloids coniine, nicotine, atropine, retrorsine, solanidine, and strychnine were tested to measure the performance of the method. Fortifications at 10 and 1 μg/g of the six model alkaloids in alfalfa hay, bovine rumen content, liver, urine, and serum were prepared. The method recovered the six alkaloids in the range of 113-82% at the 10 μg/g level and 113-72% at the 1 μg/g level. Qualitative screening methods using a modified commercial TLC system and GC/MS were developed. Theoretical detection limits for qualitative screening ranged from 0.2 to 1.0 μg/g, while theoretical detection limits for GC/NPD ranged from 0.025 to 0.2 μg/g for the compounds studied using a nominal 5 g sample. The method was used successfully in a diagnostic case to identify lupine alkaloids in rumen contents

Normal phase liquid chromatographic analysis of toxic norditerpenoid alkaloids

AbstractA normal phase, isocratic, analytical high performance liquid chromatographic (HPLC) method has been developed for the analysis of toxic methylsuccinimidoanthranoyllycoctonine (MSAL) norditerpenoid alkaloids occurring in poisonous larkspurs (Delphinium sp.). The method has good sensitivity, specificity for MSAL norditerpenoid alkaloid and rapid analysis times. The technique employs 5 μm neutral alumina as the stationary phase and utilizes a mixture of hexane: 95% isopropyl alcohol as the mobile phase. Accurate and reproducible analyses can be performed on 1 g samples of plant material. The method has been applied to the analysis of the chemical phenology of the MSAL norditerpenoid alkaloids methyllycaconitine and 14‐deacetylnudicauline in three species of tall larkspurs (Delphinium barbeyi, D. occidentale, D. glaucescens). Analytical results confirm the primary occurrence of these toxic alkaloids in early vegetative tissues of these plants, their concentration in reproductive plant tissues and their reduction in level with plant maturation. The chemical phenology results further confirm the observed difference in the toxicity of the three tall larkspurs (D. barbeyi > D. glaucescens > D. occidentale) to livestock. Intraspecies differences of toxic alkaloid occurrence associated with site were also demonstrated.

The applicability of Cladophora glomerata (L.) Kütz in an active bio-monitoring technique to monitor heavy metals in the river Danube

Within the scope of active bio-Monitoring of heavy metals in the river Danube the bioaccumulative capability of Cladophora glomerata was used. Instead of a natural substrate in the littoral zone of the river, a floating artificial substrate was used to eliminate the majority of changes caused by the water regime. The dimensions and the structure of this substrate were designed to suit the requirements of the colonization of C. glomerata and that of the quantitative sampling of plant material for the subsequent heavy metal analysis. The heavy metal concentration in C. glomerata significantly differs according to its developmental stages and spatial (vertical) position. Both of them strongly depend on and correlated with the changes in the dry weight of the Cladophora itself. According to our field experiments in the continuously growing Cladophora web this ‘weight dilution’ effect can be considered one of the most significant factors which influences the heavy metal concentration directly. Through the changes in dry weight other physical-chemical parameters (flood effect, light condition, temperature, conductivity and redox potential) seem to be the most important factors influencing indirectly the heavy metal uptake and accumulation.

Development of an enzyme immunoassay for the determination of tobacco alkaloids in plant material

A competitive enzyme immunoassay (EIA), using anti-nornicotine antibodies is described. The specificity of these antibodies was checked by a high pressure liquid chromotographic (HPLC) procedure. Following purification, the alkaloid extracts were simultaneously analysed by EIA and HPLC and similar results were obtained. The high sensitivity of EIA and its good specificity toward the major tobacco alkaloids enabled us to perform analysis on crude extracts prepared from very small samples (ca. 1 mg dry weight) of plant material. The method can therefore be applied to the localization of alkaloids in Nicotiana plants and cell suspensions.

Essential Oil Content and Composition ofTeucrium arduiniL.

ABSTRACT Two samples of plant material of Teucrium arduini L., which were collected in 1989 and 1990 were hydrodistilled to produce oil yields of 0.07% and 0.18% (v/w) respectively. GC and GC/MS analysis revealed that germacrene D (23.4% and 57.8%) and β-caryophyllene (17.3% and 13.5%) were the main components of the oils.

Determination of selenium by inductively coupled plasma mass spectrometry utilizing a new hydride generation sample introduction system.

An inductively coupled plasma mass spectrometer with a newly designed continuous flow hydride generator was used for the determination of Se in biological materials. The design of the hydride generator was important in minimizing interference from HCl and in maximizing analytical sensitivity. Two sample preparation procedures incorporating either 3.8 or 7.2 M HCl in the final sample solutions were compared. Interference from Cu was eliminated by the addition of 0.2 M NaI to the sodium borohydride solution (3.8 M method) or by maintaining a high concentration of HCl in the sample solution (7.2 M method). The 3.8 M method had the advantage of minimizing exposure of expensive equipment to corrosive HCl fumes, whereas the 7.2 M method did not contaminate equipment with I and had no measurable sample-to-sample cross-contamination. In practice, cross-contamination from sample to sample in both methods was negligible during analysis. An important factor in minimizing cross-contamination from sample to sample was the elimination of the air bubble normally entrained between samples. Determination of isotopic tracer enrichment was linear from 0 to 320% enrichment, which provided a broad range for isotope dilution analysis. A detection limit of 6.4 pg of Se was observed under optimum conditions, whereas a detection limit of 1.3 ng of Se was found for routine analysis of 1-g samples of plant material. Selenium was accurately determined by isotope dilution analysis in a variety of biological reference materials.

Determination of tryptophan in pure proteins and plant material by three methods

The tryptophan content of three pure proteins and eight samples of plant material was determined by three different methods (1–3). Protein hydrolysis was performed in the presence of Ba(OH)2(1), NaOH(2) or pronase (3). The tryptophan released was isolated by gel filtration (1) or ion-exchange chromatography (2) or neither (3) and was assayed by colorimetry with ninhydrin (1, 2) or p-dimethylaminocinnamaldehyde (3). The tryptophan recovered from pure proteins averaged 99.0 (1), 94.3 (2) and 98.1%(3). Method 1 was found to yield the highest and least dispersed values for the tryptophan content of samples of plant material.

GIS-ASSISTED REGRESSION ANALYSIS TO IDENTIFY SOURCES OF SELENIUM IN STREAMS

ABSTRACT: Using a geographic information system, a regression model has been developed to identify and to assess potential sources of selenium in the Kendrick Reclamation Project Area, Wyoming. A variety of spatially distributed factors was examined to determine which factors are most likely to affect selenium discharge in tributaries to the North Platte River. Areas of Upper Cretaceous Cody Shale and Quaternary alluvial deposits and irrigated land, length of irrigation canals, and boundaries of hydrologic subbasins of the major tributaries to the North Platte River were digitized and stored in a geographic information system. Selenium concentrations in samples of soil, plant material, ground water, and surface water were determined and evaluated. The location of all sampling sites was digitized and stored in the geographic information system, together with the selenium concentrations in samples. A regression model was developed using stepwise multiple regression of median selenium discharges on the physical and chemical characteristics of hydrologic subbasins. Results indicate that the intensity of irrigation in a hydrologic subbasin, as determined by area of irrigated land and length of irrigation delivery canals, accounts for the largest variation in median selenium discharges among subbasins. Tributaries draining hydrologic subbasins with greater intensity of irrigation result in greater selenium discharges to the North Platte River than do tributaries draining subbasins with lesser intensity of irrigation.

Evaluation of automated analysis of 15N and total N in plant material and soil

Simultaneous determination of 15N and total N using an automated nitrogen analyser interfaced to a continuous-flow isotope ratio mass spectrometer (ANA-MS method) was evaluated. The coefficient of variation (CV) of repeated analyses of homogeneous standards and samples at natural abundance was lower than 0.1%. The CV of repeated analyses of 15N-labelled plant material and soil samples varied between 0.3% and 1.1%. The reproductibility of repeated total N analyses using the automated method was comparable to results obtained with a semi-micro Kjeldahl procedure. However, the automated method gave results which were 3% to 5% higher than those obtained with the Kjeldahl procedure. Since only small samples can be analysed, careful sample homogenization and fine grinding are very important. Evaluation of a diffusion method for preparing nitrate and ammonium in solution for automated 15N analysis showed that the recovery of inorganic N in the NH3 trap was lower when the N was diffused from water than from 2 M KCl. The results also indicated that different proportions of the NO3- and the NH4+ in aqueous solution were recovered in the trap after combined diffusion. The method is most suited for diffusing either NO3- or NH4+ alone, but can be used for combined diffusion of the two ions.

Levels of Cd and Some other Trace Elements in Soils and Crops as Influenced by Lime and Fertilizer Level

Abstract Plant material and soil samples from seven long-term field experiments with different liming rates and fertilizer levels were analysed for Mn, Zn, Cu, Ni, Pb, Cd, Cr and As. Liming consistently decreased the plant levels of Mn, Zn and Ni, whereas Pb, Cr and As did not seem to be influenced. Cu was only slightly influenced and the influence on Cd levels varied inconsistently in grain/seeds. In straw/ley the expected decrease in Cd level with increasing base saturation and pH was found. Liming consistently decreased easily soluble fractions of Zn, Ni and Pb in soils. Only Cd was influenced by the level of fertilizer, with an obvious tendency towards increasing Cd levels in plants and soils at increasing rates of fertilizer application.

The effects of feeding by the black bean aphidAphis fabae Scop. (Homoptera: Aphididae) on copper and cadmium accumulation in broad bean (Vicia faba L.)

Broad beans (Vicia faba L.), cultured hydroponically were supplied with 100 μg mL(-1) copper or 50 μg mL(-1) cadmium in nutrient solution. Samples of plant material from both nutrient regimes were analysed before and after infestation by the black bean aphid (Aphis fabae Scop.). Heavy aphid infestation resulted in a significant reduction in copper content of shoots in comparison with uninfested plants. A similar, but less well- defined, situation occurred in the case of cadmium.Further investigations examined the effects of different levels of aphid infestation on the above phenomena. In all cases the presence of feeding aphids reduced elemental accumulation in plant shoots. Long term infestation with population densities as low as three adult aphids showed a reduction in shoot copper and cadmium content.

Flow-Injection Extraction-Spectrophotometric Determination of Copper with Dithiocarbamates

Several salts of MN-substituted derivatives of dithiocarbamic acid were studied as potential reagents for flow-injection extraction-spectrophoto metric determination of copper. A specific and sensitive method for the determination of copper was developed. Copper is extracted with a chloroform solution of lead diethyldithiocarbamate (DDTC) and the absorbance of the Cu-DDTC complex is measured at 436 nm. Effects of total flow rate, sample volume, mixing and extraction coils length are studied. The detection limit is 0.04 ppm of Cu and calibration graph is linear up to 2 ppm Cu. The method developed was applied to the determination of copper in samples of water and plant materials showing good precision and accuracy.

Oviposition by the banded fruit weevil, Phlyctinus callosus (Schoenherr) (Coleoptera: Curculionidae), in deciduous fruit orchards in South Africa

AbstractOviposition sites of Phlyctinus callosus (Schoenherr) in an apple and a nectarine orchard in the South Western Cape, South Africa, were investigated. No eggs were found on the fruit trees, only in different fractions of the orchard floor, viz. in orchard weeds, leaf litter and soil. Significantly more oviposition took place in plant material on the orchard floor than in the top 20 mm of the soil. Microscopic dissection of samples of such plant material revealed that females prefer to oviposit in confined or hollow spaces in moist, live or decaying plant tissue on the soil surface or in weeds comprising the cover-crop. P. callosus females favoured certain weeds above others for oviposition. The dispersion pattern of eggs in the cover-crop was contagious. The implications of the observed ovipostion behaviour in terms of control strategy, and for exploitation in a monitoring system for this species, are discussed.

Quantification by ELISA of Cytokinins in Root‐Pressure Exudates of Urtica dioica Plants Grown under Different Nitrogen Levels

SummaryELISAs for [9R]iP, [9R]Z and (diH) [9R]Z have been worked out which, in combination with HPLC., allow the quantitative determination of cytokinins of the isopentenyladenin‐, zeatin‐ and dihydrozeatin‐type in samples of plant material. The three ELISAs are optimally applicable in the range from 0.5 to 20 pmoles of cytokinins per assay but reliable measurements can still be performed down to 0.05 pmoles. The assay has been applied to root pressure exudates obtained from Urtica dioica plants grown under controlled conditions and at different nitrogen (nitrate) levels. The predominant cytokinins of the xylem exudate were Z, Z‐nucleotide, iP, [9R]iP and iP‐nucleotide, while (diH)Z was present to a minor extent. The concentrations of these compounds were found to range between 0.2 and 3 pmoles per ml exudate.Interestingly, no effect of the different nitrogen nutrition on the pattern and concentration of cytokinins in the xylem exudate could be established.

Determination of phosphate and phosphite in plant material by gas chromatography-mass spectrometry and ion chromatography

A method is described for the rapid and simultaneous detection of phosphate and phosphite in samples of plant material as small as 10 mg fresh weight. Samples are extracted into formic acid-isopropanol, clarified by the addition of chloroform and partially purified by sequential passage through cation- and anion-exchange resins. The analytes can then be separated directly by single-column anion-exchange chromatography using a conductivity detector. Alternatively they can be separated by capillary gas chroamtography after the formation of tert.-butyldimethylsilyl esters. Recoveries of 95% or better were achieved, estimated both by the addition of 32P or by mass addition. The lower limit of detection was 100 ng using ion chromatography and 100 pg with mass spectrometry.

Alternative Gramineous Hosts of Leptosphaeria nodorum Including Two New Records for the U. S. A.

Abstract Leptosphaeria nodorum was isolated from various wheat sources (seeds, seedling, straw, and volunteers) and from triticale, little wild barley, ryegrass, smooth bromegrass, aegilops, quackgrass, Bermuda grass, and air. The level of seed contamination in wheat cultivars varied from 3–63%. Initial detection of the pathogen from field samples of plant material varied from 5–58%. Four out of the 12 plates exposed to the air showed growth of the pathogen. The presence of spores from aerial sporetrapping decreases to zero by 30 December. The pathogen was undetected from the leaf samples of wheat and triticale from 15 January to 15 February. Spore size and cultural growth differed among the various isolates. Isolates from wheat straw, Bermuda grass, little wild barley, and triticale were fluorescent variable while the other isolates fluoresced under NUV light. Symptoms were induced when wheat cv.‘Callahan 513’ and four other grasses were inoculated with isolates of L. nodorum from various gramineous sources. The infection by the pathogen on ‘Callahan 513’ was greater than the infection of the same isolates in their gramineous weed hosts. Ryegrass and Bermuda grass were demonstrated as additional alternative gramineous hosts of L.nodorum in the United States.

Single-sample technique for measuring oxygen production and consumption in macrophytic algae

Macroalgae production studies are handicapped by the broad range of variability within experimental replicates. Practically, it is impossible to obtain identical duplicate samples of plant material for the dark and light bottles. A new modification of the oxygen technique, described here, eliminates this difficulty, and also provides an approximation of the respiration in the light bottle. It consists of measurements of dissolved oxygen changes, produced by a single sample of algal biomass, incubated in short alternate periods of light and dark. In this way, each thallus tested provides daily curves of net photosynthesis and respiration. From the data obtained, daily curves of primary productivity are extrapolated.

Signal Enhancement and Elimination of Water-Vapor Interference in Fourier-Transformed Infrared Photoacoustic Spectroscopy of Powdered Plant Materials

A simple and efficient method to enhance the Fourier-transformed infrared photoacoustic signal from powdered samples of plant materials is described. The increase in signal strength appears to be inversely related to the rate of absorption of added water by the dry cellulose, starch, lignin, and hemicellulose of the plant. The method also provides an accurate and convenient technique for obtaining photoacoustic infrared spectra of powdered plant materials free of interference from incidental water vapor in the sample. A hypothesis to account for the nonlinear behavior of the interference is proposed.