Mmol Dm Research Articles

5-Bromo- and 3,5-dibromo-2-hydroxy-N-phenylbenzamides — inhibitors of photosynthesis

Abstract5-Bromo-(Br-PBA) and 3,5-dibromo-2-hydroxy-N-phenylbenzamides (Br2-PBA) inhibited photosynthetic electron transport (PET) and their inhibitory efficiency depended on the compound lipophilicity as well as on the electronic properties of the R substituent in the N-phenyl moiety. Br-PBA showed higher PET inhibiting activity than Br2-PBA with the same R substituent. The most effective inhibitors in the tested series were the derivatives with R = 3-F (Br-PBA; IC50 = 4.3 μmol dm−3) and R = 3-Cl (Br2-PBA; IC50 = 8.6 μmol dm−3). Bilinear dependence of the PET inhibiting activity on the lipophilicity of the compounds as well as on the Hammett constant, σ, of the R substituent was observed for both investigated series. Using EPR spectroscopy it was found that the site of action of the tested compounds in the photosynthetic apparatus is situated on the donor side of PS 2, in D· or in the Z·/D· intermediates. Interaction of the studied compounds with chlorophyll a and aromatic amino acids present in the pigment-protein complexes mainly in photosystem 2 was documented by fluorescence spectroscopy.

Bioaccumulation of PBDE congener 2,2′,4,4′-tetrabromodiphenyl ether by Heterosigma akashiwo in response to different nutrient concentrations

Abstract Changes in the bioaccumulation of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) in the marine alga Heterosigma akashiwo (Raphidophyceae) were examined for different concentrations of nitrate (0, 128, and 512 μmol dm−3) and phosphate (0, 8, and 32 μmol dm−3) in the semi-continuous culture with 20% renewal rate. The BDE-47 content per cell and per culture, as well as the accumulated percentage of available BDE-47, presented a significant decreasing trend with the increase in nitrate and phosphate concentrations. The N-0 (4.0 × 10−6 ng cell−1) and P-0 (5.8 × 10−6 ng cell−1) treatments had significantly higher BDE-47 content per cell than other treatments. In comparison, the difference in BDE-47 per algal culture and accumulated percentage between the nitrate treatments or phosphate treatments was not as obvious as the BDE-47 content per cell. BDE-47 per cell presented significantly negative correlation with nitrate and phosphate concentrations, and the accumulated BDE-47 was in positive correlation with lipid content. log BAFlip for BDE-47 in H. akashiwo ranged from 6.70 to 7.25. The results of this study indicate that variation in BDE-47 accumulation by H. akashiwo corresponds to the change in cellular lipid content induced by different nitrate and phosphate concentrations.

Reliability of protonation constants of vildagliptin dimers by the regression analysis of pH-titration data

Abstract Protonation constants of protonated monomers and dimers of the vildagliptin are determined potentiometrically. For the low concentration c L = 3.3 mmol dm−3 the monomers L and LH dominate, while for a higher concentration c L = 6.3 mmol dm−3 the dimers L2H2, L2H3, L2H4 and L2H are mainly present. The algorithm used has little influence on the precision of the formation constants in comparison with the reproducibility of the titration. The mixed protonation constants of vildagliptin dimers Lq Hr at various temperatures are determined using FBSTAC4 and HYPERQUAD regression analysis of the potentiometric titration data. The accuracy of the protonation constants log10 βqr depends on the accuracy of the group parameters. As two group parameters L 0, H T are ill conditioned in a model, their determination is therefore uncertain; both can significantly cause a systematic error in the estimated common parameters log10 βqr . Using various regression diagnostics the goodness-of-fit proves the reliability of all parameter estimates. A rough estimation of thermodynamic enthalpies ΔH 0 (kJ mol−1) and entropies ΔS 0 (J K−1 mol−1) is determined from the temperature variation of protonation constants. The enthalpy shows the protonation process is exothermic, and the entropy indicates that it is spontaneous.

Platinum Dissolution in Nitrogen Oxides-Containing HClO4 Solution Studied by Electrochemical Quartz Crystal Microbalance

Platinum (Pt) dissolution has been elucidated by measuring a mass loss of Pt black-deposited Au quartz resonators in 0.1 mol dm-3 HClO4 containing NaNO2. A continuous weight loss of ca. 50 ng cm-2 cycle-1 was detected at [NaNO2] = 0.01 mol dm-3 under the potential cycling between 0.6 and 1.4 V vs. RHE. The magnitude of Pt dissolution depends on the concentration of NaNO2 and the range of potential cycling. The average mass loss decreases to 5~10 ng cm-2 cycle-1 at [NaNO2] = 1 mmol dm-3. The Pt dissolution occurs when the higher potential limit is more than 1.0 V vs. RHE and the lower potential limit is less than 0.9 V vs. RHE, suggesting that the reduction of Pt oxide in the presence of NaNO2 in the bulk solution contributes to the dissolution.

Impact of 1 mmol dm−3 concentrations of small molecules containing nitrogen-based cationic groups on the oxygen reduction reaction on polycrystalline platinum in aqueous KOH (1 mol dm−3)

Alkaline anion-exchange membranes (AAEMs) containing cationic head-groups (e.g. involving quaternary ammonium and imidazolium groups) are of interest with regard to application in alkaline polymer electrolyte fuel cells (APEFCs). This initial ex situ study evaluated the effect of 1 mmol dm(-3) concentrations of model molecules containing (AAEM-relevant) cationic groups on the oxygen reduction reaction on a polycrystalline platinum disk (Ptpc) electrode in aqueous KOH (1 mol dm(-3)). The cationic molecules studied were tetramethylammonium (TMA), benzyltrimethylammonium (BTMA), 1-benzyl-3-methylimidazolium (BMI), 1-benzyl-4-aza-1-azoniabicyclo[2.2.2]octane (BAABCO) and 6-(benzyloxy)-N,N,N-trimethylhexan-1-aminium (BOTMHA). Both cyclic and hydrodynamic linear sweep rotating disk electrode voltammetry techniques were used. The resulting voltammograms, derived estimates of apparent electrochemically active surface areas, Tafel slopes, apparent exchange-current densities and the number of electrons transferred (per O2 molecule) were compared. The results strongly suggest that 1 mmol dm(-3) concentrations of BTMA, BAABCO, and (especially) BMI seriously inhibit the catalytic activities of Ptpc in an aqueous KOH electrolyte at 25 °C. The negative influence of (benzene-ring-free) TMA and Cl(-) anions (KCl control experiment) appeared to be less severe. The separation of the trimethylammonium group from the benzene ring via a hexyloxy spacer chain (in BOTMHA) also produced a milder negative effect.

Flow Chemiluminescence Determination of Antimony(III,V) Using a Rhodamine B-Cetyltrimethylammonium Chloride Reversed Micelle System Following Liquid–Liquid Extraction

A flow chemiluminescence (CL) method combined with a liquid-liquid extraction technique is proposed for the indirect determination of antimony in aqueous samples using rhodamine B (RB). In the liquid-liquid extraction process, the antimony(V) chloro-complex anion, [SbCl(6)](-), was extracted from an aqueous acidic solution into toluene via ion-pair formation with the protonated RBH(+) ion. Upon mixing the extract with a reversed micellar reagent solution of cetyltrimethylammonium chloride (CTAC) in 1-hexanol-cyclohexane/water (0.60 mol dm(-3) H(2)SO(4)) containing cerium(IV), uptake of the ion-pair by CTAC reversed micelles occurred easily, followed by an oxidation reaction of RB with Ce(IV) in the CL process. The CL signal produced was then measured. Using a flow injection system, the detection limits (DL) of 0.25 μmol dm(-3) Sb(III) and 0.20 μmol dm(-3) Sb(V), and linear calibration graphs with dynamic ranges from the respective DLs to 16 μmol dm(-3) for Sb(III) and Sb(V) were obtained under optimized experimental conditions. The proposed method was successfully applied to a mixture of Sb(III) and Sb(V), where total antimony, Sb(III) + Sb(V), was measured using ceric sulfate as an oxidant to oxidize Sb(III) to Sb(V) prior to extraction, Sb(V) was determined directly without the use of an oxidant, and Sb(III) was calculated by difference.

Fabrication of an efficient polyaniline–polyphenol oxidase based biosensor for catechol

Amperometric polymerization of aniline was carried out in the presence of TritonX-100. Entrapment of tyrosinase (polyphenol oxidase, PPO) onto polyaniline in the presence of TritonX-100 with glutaraldehyde as a cross-linking agent results in a biosensor for polyphenols. Catechol is taken as a model compound. Cyclic voltammetric studies reveal the electroactivity of catechol on the developed biosensor. HR-SEM shows the surface morphology of polyaniline prepared in the presence of TritonX-100 (PANI(T)) and polyphenol oxidase entrapped polyaniline in the presence of TritonX-100 (PANI(T)–PPO). The optimum reaction conditions to construct the polyaniline, tyrosinase based catechol biosensor are studied. The linear concentration range is from 5 × 10−7 to 1.65 × 10−4 mol dm−3, with a Michealis–Menten constant Km = 85.44 μmol dm−3 and an activation energy of 41.74 kJ mol−1. It retains 65% of the original activity after 25 days, which is much higher than that of other biosensors. With a lower quantity of enzyme loading, better response, sensitivity, shelf life and higher stability are observed. The developed biosensor was used to quantify catechol in green tea samples and the results were compared with those from HPLC.

Electrochemical metal-ion sensor based on a cobalt phthalocyanine complex captured in Nafion® on a glassy carbon electrode

This article describes an electrochemical metal-ion sensor based on a cobalt phthalocyanine (CoPc) complex and determination of its sensor activity for some transition metal ions. Ag+ and Hg2+, among several transition metal ions, coordinate to the sulfur donors of CoPc and alter the electrochemical responses of CoPc in solution, indicating possible application of the complex as Ag+ and Hg2+ sensor. For practical application, CoPc was encapsulated into a polymeric cation exchange membrane, Nafion, on a glassy carbon electrode and used as an electrochemical coordination element. This composite electrode was potentiometrically optimized and potentiometrically and amperometrically characterized as transition metal-ion sensors with respect to reproducibility, repeatability, stability, selectivity, linear concentration range, and sensitivity. A µmol dm−3 sensitivity of the CoPc-based sensor indicates its possible practical application for the determination of Ag+ and Hg+2 in waste water samples.

Alternating current cloud point extraction on a microchip: A comprehensive study

We present a comprehensive study of alternating current cloud point extraction (ACPE) on a microchip. ACPE is an extraction technique for preconcentration of membrane-associated biomolecules. To characterize and optimize ACPE, we carried out ACPE experiments under various experimental conditions including amplitude and frequency of applied voltages, flow velocity, and concentration of surfactant, analyte, and salt. We found that ACPE has an amplitude threshold (15 V(p-p)), above which the extraction was more efficient. The dependence of the extraction on frequency (>5 MHz) was insignificant. Efficient extraction was achieved when the velocity of the test solution was 0.10∼0.67 mm s⁻¹ and the concentration of surfactant was 0.10∼1.0%. In contrast, the extraction was independent of the concentration of analytes (0.20∼20 μmol dm⁻³). The technique was applicable to solutions with a salt concentration of 0.050∼0.15 mol dm⁻³ under temperature control of the devices. Solution temperature in ACPE was also studied. These results provide guidelines for use of the ACPE technique in microfluidic chemical and biochemical analyses.

Kinetics of the reaction between 1,3-diphenylisobenzofuran and nitrogen dioxide studied by steady-state fluorescence

1,3-Diphenylisobenzofuran (DPBF) is a fluorescent molecule which is believed to react highly specifically toward reactive oxygen species such as singlet oxygen (1O2), hydroxy (HO·), alkyloxy (RO·), and alkylperoxy (ROO·) radicals. In all cases the reaction product is 1,2-dibenzoylbenzene. In order to prove that DPBF gives the same product in contact with reactive nitrogen species, its reaction with nitrogen dioxide radical has been studied in 2,2,4-trimethylpentane using the steady-state fluorescence method and mass spectrometry. The progress of the studied reaction was measured by observation of changes in fluorescence intensity of DPBF after addition of nitrogen dioxide (NO2). The rate constants of DPBF fluorescence decay affected by NO2 have been determined. Experiments were conducted over the temperature range of 13–37 °C and for NO2 concentrations from 0.02 to 0.14 mmol dm−3. It has been found that the reaction between 1,3-diphenylisobenzofuran and nitrogen dioxide proceeds in two steps. The first step is a very rapid reaction whose rate could not be measured under established experimental conditions. The second step is slower. The reaction product was identified by registration of mass spectra. The probable reaction mechanism is proposed.

Photocatalytically driven dissolution of macroscopic metal surfaces. Part 1: Silver

We present the first observation of photocatalytically driven, hydrogen peroxide mediated, dissolution of a macroscopic metal surface. Specifically, we report on the dissolution of silver in the presence of photocatalytically generated H2O2 produced by ultra-band gap illumination of TiO2 at 365 nm in the presence of O2. Direct measurements of photocatalytically generated H2O2 in the TiO2 suspensions studied indicate that peroxide concentration never exceeds 32 μmol dm−3. However, comparison of electrochemical quartz crystal microgravimetrically determined rates of Ag dissolution with rates recorded from solutions spiked with H2O2 indicates that dissolution occurs at a rate equivalent to a bulk solution concentration of ∼100 mmol dm−3 H2O2. This suggests that a local enhancement occurs in the rate of photocatalytically induced metal dissolution on surfaces under direct illumination, which is attributed to two causes: (i) local modification of the TiO2 by deposition of dissolved Ag, so increasing its efficiency for peroxide generation; and (ii) peroxide generation local to the electrode surface mitigating against photolytic loss reactions seen to occur in the solution bulk. The photoinduced dissolution process is found to be both highly controllable/light switchable and spatially specific.

Continuous sorption of synthetic dyes on dried biomass of microalga Chlorella pyrenoidosa

AbstractThe sorption of thioflavine T (TT) and malachite green (MG) cationic synthetic dyes on dried biomass of green microalga (Chlorella pyrenoidosa) immobilised in polyurethane foam under continuous column systems conditions using spectrophotometric methods of detection was investigated. Data characterising the sorption of TT and MG on microalgal biomass immobilised in polyurethane foam in a column system from single (C 0 = 25 μmol dm−3) or binary equimolar (C 0 = 25 μmol dm−3) dye solutions in the form of breakthrough curves were well described by the Thomas (R 2 = 0.994–0.912), Yoon-Nelson (R 2 = 0.994–0.911), and Clark (R 2 = 0.993–0.911) models. Useful parameters characterising the sorption column system were obtained from these mathematical models. The Thomas model, in particular, provided the Q max (maximal sorption capacity in μmol g−1) parameter for characterisation of biosorbent and also for evaluation of competitive effects in the TT and MG dyes sorption. For the purposes of biomass regeneration, a one-step desorption of the dyes studied from the microalgal biomass in batch and continuous column systems was performed. Efficiency of TT desorption from microalgal biomass increased in the order: deionised H2O (50.7 %), 99.5 vol. % 1,4-dioxane (67 %), 20 mmol dm−3 NiCl2 (83 %), 96 vol. % ethanol (85 %), 0.1 mol dm−3 HCl (89 %), 1 mol dm−3 acetic acid (89 %). In the case of MG, the desorption efficiency increased in the order: deionised H2O (13 %), 20 mmol dm−3 NiCl2 (50 %), 0.1 mol dm−3 HCl (91 %), 99.5 vol. % 1,4-dioxane (94 %), 1 mol dm−3 acetic acid (99 %), 96 vol. % ethanol (> 99 %). The presence of carboxyl, phosphoryl, amino, and hydroxyl groups, the important functional groups for sorption of cationic xenobiotics, was also confirmed on the algae biomass surface by potentiometric titration and ProtoFit modelling software. The data obtained showed that the dried immobilised algae biomass could be used as a sorbent for removing toxic xenobiotics from liquid wastewaters or contaminated waters and also presenting the possibilities of mathematical modelling of sorption processes in continuous column systems in order to obtain important parameters for use in practice.

Spectrofluorimetric, spectrophotometric and chemometric analysis of wheat grains infested by Sitophilus granarius

Invisible infestation of wheat grains by Sitophilus granarius during postharvest handling is one of the main problems particularly for small enterprises and farm grain storage facilities due to the lack of cheap and fast methods for early detection of infestation, especially when only a small proportion of grain is infested by larvae. In order to determine whether the spectrofluorimetric, spectrophotometric or chemometric analysis of various extracts of wheat grains infested by S. granarius larvae could be used for detection of infested grain, four different types of extracts: 50 mmol dm−3 Tris–HCl pH 8.9, aqueous iso-propanol (φ = 0.55), methanol, and aqueous trichloroacetic acid (γ = 0.2 mg cm−3), of non-infested and infested wheat grains have been examined for fluorescence properties and UV/VIS spectral characteristics, while the chemometric analysis included determination of protein, reactive amino groups, polyphenols and soluble sugar content. Analysis of extracts revealed significant differences in UV/VIS spectral characteristics, level of reactive amino groups and polyphenol content between infested and non-infested grains. The results obtained indicate that instrumental analysis of spectral characteristics of grain extracts could be used as a method for determination of grain infestation.

Experimental study on the nickel (II) removal from aqueous solutions using silica fume with/without apocarbonic anhydrase

Abstract The silica fume is a fine-grain, thin and very high surface area silica. Although the silica fume is a waste material of industrial applications, it has become the most valuable by-product among the pozzolanic materials due to its very active and high pozzolanic property. In this study, the potential use of silica fume in the remediation of polluted heavy metal water to remove nickel ions is presented. For studying metal adsorption, 1 g of silica fume has been taken as adsorbent and then it has been suspended in 50 ml of 3 mmol dm−3 NiCl2, at pH between 3 and 9 and contacted batchwise in a thermostatic (t = 25°C ± 0.1°C) water-bath agitator for 1 h to enable equilibration of the sorbent and solution phases. The nickel concentrations in the samples taken from the silica fume treated aqueous solutions of polluted river water with/without apocarbonic anhydrase (apoCA) and NiCl2 solution have been determined by spectrophotometric method using dithizone. The nickel concentration in the samples of sili...

Electrochemical Behaviour for Europium Doped Tantalum Oxide Coated Glass Carbon Electrode

Europium doped tantalum oxide (europium-Ta2O5) particles were synthesized with a low temperature hydrothermal method. The electrochemical behaviour of an europium-Ta2O5 film electrode in 0.1 mol dm-3 KCl solution containing 5 mmol dm-3 K3Fe(CN)6 was investigated using cyclic voltgrammetry (CV). The CV results indicated that the europium-Ta2O5 film electrode exhibited good stable and reversible electrochemistry properties. The electrochemical reaction of K3Fe(CN)6 was a diffusion-controlling process on the europium-Ta2O5 film electrode. The europium-Ta2O5 particles might have potential applications in electrochemical fields.

Sodium–potassium synergism inTheobroma cacao: stimulation of photosynthesis, water‐use efficiency and mineral nutrition

In ecological setting, sodium (Na(+)) can be beneficial or toxic, depending on plant species and the Na(+) level in the soil. While its effects are more frequently studied at high saline levels, Na(+) has also been shown to be of potential benefit to some species at lower levels of supply, especially in C4 species. Here, clonal plants of the major tropical C3 crop Theobroma cacao (cacao) were grown in soil where potassium (K(+)) was partially replaced (at six levels, up to 50% replacement) by Na(+), at two concentrations (2.5 and 4.0 mmol(c) dm(-3)). At both concentrations, net photosynthesis per unit leaf area (A) increased more than twofold with increasing substitution of K(+) by Na(+). Concomitantly, instantaneous (A/E) and intrinsic (A/g(s)) water-use efficiency (WUE) more than doubled. Stomatal conductance (g(s)) and transpiration rate (E) exhibited a decline at 2.5 mmol dm(-3), but remained unchanged at 4 mmol dm(-3). Leaf nitrogen content was not impacted by Na(+) supplementation, whereas sulfur (S), calcium (Ca(2+)), magnesium (Mg(2+)) and zinc (Zn(2+)) contents were maximized at 2.5 mmol dm(-3) and intermediate (30-40%) replacement levels. Leaf K(+) did not decline significantly. In contrast, leaf Na(+) content increased steadily. The resultant elevated Na(+)/K(+) ratios in tissue correlated with increased, not decreased, plant performance. The results show that Na(+) can partially replace K(+) in the nutrition of clonal cacao, with significant beneficial effects on photosynthesis, WUE and mineral nutrition in this major perennial C3 crop.

Spatial extent and historical context of North Sea oxygen depletion in August 2010.

Prompted by recent observations of seasonal low dissolved oxygen from two moorings in the North Sea, a hydrographic survey in August 2010 mapped the spatial extent of summer oxygen depletion. Typical near-bed dissolved oxygen saturations in the stratified regions of the North Sea were 75-80% while the well-mixed regions of the southern North Sea reached 90%. Two regions of strong thermal stratification, the area between the Dooley and Central North Sea Currents and the area known as the Oyster Grounds, had oxygen saturations as low as 65 and 70% (200 and 180μmoldm-3) respectively. Low dissolved oxygen was apparent in regions characterised by low advection, high stratification, elevated organic matter production from the spring bloom and a deep chlorophyll maximum. Historical data over the last century from the International Council for the Exploration of the Sea oceanographic database highlight an increase in seasonal oxygen depletion and a warming over the past 20years. The 2010 survey is consistent with, and reinforces, the signal of recent depleted oxygen at key locations seen in the (albeit sparse) historical data.

Content of bioactive compounds in semi-dry red wine

The aim of the present work was to compare the content of bioactive compounds (polyphenols and minerals) in semi-dry wines. The material for the study consisted of 6 types of semi-dry red wine originating from Bulgaria (Sofino Melnik), Hungary (Loci), France (Bongeronde) and Spain (Don Kichot). The wines were subjected to organoleptic scoring assessment, followed by analyses of crude ash, anthocyanins, the total content of phenol compounds, zinc, manganese, copper, iron and magnesium. Additionally, the browning index was determined. All the samples attained positive organoleptic assessment. The highest score for the color was given to the wines from France and Spain. The total acidity in the analyzed red wines ranged between 4.97 g dm –3 (Spanish wine) and 5.56 g dm –3 (Bulgarian wine), which fulfills the quality requirements for grape wine. Grape wine contains from 1.0 to 4.0 g dm–3 of polyphenols. The analyzed wine samples contained a slightly lower concentration of phenolic compounds: 1.28 g dm –3 on average. The average content of p-coumaric acid in the examined samples was 1.85 mmol dm –3 . The concentration of anthocyanins, compounds responsible for the color of wine, was significantly lower in Bulgarian and Hungarian wine samples (26.05±0.25 mg dm–3 and 23.60±0.80 mg dm–3 respectively), in comparison with French (59.90±0.20 mg dm–3) and Spanish wine particularly (75.90±2.40 mg dm –3 ). All the analyzed wine samples, independently of their place of manufacture, achieved high organoleptic assessment, especially for clarity and color. The highest rated wines from France were characterized a high level of bioactive compounds: total polyphenols and anthocyanins. They also had a high content of crude ash and minerals such as Mg, Mn, Zn. Relatively high concentrations of polyphenols, anthocyanins and crude ash were also determined in Spanish wines.

The influence of pregnancy and lactation on the magnesium and calcium concentration in goats’ blood serum

The aim of this work was to trace differences in magnesium and calcium concentrations (both total and ionic form) between goats which were in late pregnancy and lactating goats. The study involved 30 goats. Blood samples were taken three times from each goat. Total concentrations of magnesium and calcium were determined with the colorimetric method and (A – 1.581 mmol dm–3; B – 2.052 mmol dm–3; C – 2.112 mmol dm–3). Ionic form of calcium based on using ion–selective analysis (A – 1.219 mmol dm–3; B – 1.126 mmol dm –3 ; C – 1.123 mmol dm –3 ). The study showed that mean value of both the total of calcium from each goat did not reach the reference level for this species. Ionic form of calcium was within the lever limit of the physiological norm. The content of magnesium in all the groups was within the range of reference concentrations (A – 1.051 mmol dm–3; B – 1.165 mmol dm–3; C – 1.117 mmol dm–3).

Differentiated microelement content in anthurium (Anthurium cultorum Birdsey) leaves

The main objective of the study was to determine the nutritional status in terms of the content of microelements, such as iron, manganese, zinc, copper and boron in several standard cultivars of anthurium (Anthurium cultorum Birdsey) called Baron, Choco, Midori, Pistache, President and Tropical. The plants were grown in expanded clay (ř 8-18 mm) using drip fertigation with standard nutrient for anthurium grown in inert substrates with the following components: N-NH4<1.0, N-NO3 7.5, P 1.0, K 4.5, Ca 1.5, Mg 1.0, S-SO4 1.5 (mmol dm –3 ), Fe 15, Mn 3.0, Zn 3.0, Cu 0.5, B 20.0, Mo 0.5 (µmol dm –3 ), pH 5.5-5.7, EC 1.5-1.8 mS cm–1. Every two months, anthurium indicator parts were sampled for chemical analyses. The indicator parts included fully developed leaves from plants after freshly cut flowers. The average microelement content in the indicator parts showed the following values (in mg kg –1 d.m.): Fe 47.6-58.0, Mn 36.9-45.1, Zn 60.3-67.6, Cu 5.01-6.43, B 63.5-89.0. It was found that a significant effect on the nutritional status with respect to microelements was produced by the plant cultivar type. The highest content of iron in the indicator parts was found in cv. Baron; manganese was most abundant in cv. Choco; cv. Midori was the richest in zinc and boron appeared in the highest level in cv. Pistache. Coefficients of variability (CV) of the analyzed microelements were determined. The smallest variability during 3 years of studies was shown by copper (CV 15.4-24.3%), a mean value was found in boron (CV 20.9-26.7%) and in iron (CV 25.1-31.4%), while the highest values were shown by zinc (CV 39.7-44.7%) and by manganese (CV 40.4-58.5%).