Kinetics of Shrinkage of Mushrooms during Blanching

Kinetics of shrinkage of mushroom tissue and whole mushrooms was investigated. Shrinkage of tissue was found to be described by three apparent first order reactions, consisting of an initial slow phase, a second rapid phase, and a third slow phase. The duration of each phase depended on temperature. The major part of the shrinkage took place during the rapid shrinkage period. Activation energies during this phase were 18.25 Kcal mole^?1 and 16.80 Kcal mole^?1 for mass and volume shrinkage, respectively. Results for whole mushrooms were consistent with those for tissue.     

PURIFICATION AND SOME PROPERTIES OF LINAMARASE FROM CASSAVA (Manihot esculenta) CORTEX

The enzyme linamarase (E. C. 3.2.1.21) has been purified from cassava cortex (Manihot caculenta) by techniques involving acetone precipitation, ammonium sulfate fractionation, gel filtration and ion-exchange chromatography. Two peaks of linamarase activity (A & B) were eluted by linear gradient on DEAE-Sephadex column. Both forms of the enzyme were found to catalyze similar reactions, however, at different rates. Double reciprocal plots from initial velocity data gave K_m of 1.47 mM & 1.44 mM for linamarase A & B, respectively, with linamarin as substrate. The K_m values with the artificial substrate para-nitrophenyl glucoside (PNP-G) were 0.48 mM, Both enzyme forms exhibited maximal activity at pH 6.0 and 30°C. Arrhenius plots gave activation energy (E_a) as 49 KJ/mole (11.72 Kcal mole^?1) and 36.5 KJ/mole (8.72 Kcal mole^?1) for linamarase A & B, respectively. Analysis of cyanide levels in cassava and its products with the crude enzyme showed the leaves to contain high levels of the toxic factor.     

Kinetics of Ascorbic Acid Autoxidation as a Function of Dissolved Oxygen Concentration and Temperature

The kinetics of ascorbic acid autoxidation was studied at pH 6.1 (μ= 0.08) using a buffered model system. Oxygen replenishment in the solution was accomplished by shaking the reaction vessel in a shaker water bath or by bubbling oxygen-nitrogen gas mixtures through the solution. Using the former system, a second order rate constant of 58.19 ± 11.92 min^?1 M^?1 was calculated (45°C), Since the shaker bath did not assure oxygen replenishment and dissolved oxygen levels could not be varied, the latter system was developed. The second order rate constants in the gas mixture experiments ranged from 20.80 ± 2.28 min^?1 M^?1 (30°C) to 176 ± 6.93 min^?1 M^?1 (55°C). Activation energies measured under different conditions ranged from 9.47 to 16.43 kcal mole^?1.     

Thermal Inactivation Kinetics of Wheat Germ Lipoxygenase

Thermal inactivation curves for wheat germ lipoxygenase (LPO) in partially purified and crude extracts were determined in capillary tubes at 60–68°C. The biphasic curves fitted a two-fraction first order model suggesting the presence of 2 groups of isozymes. At 60°C, the inactivation rate constants were 9.112 × 10^?-⁵ set^?1 and 9.174 × 10^?-⁶ set^?1 respectively, for thermolabile phase I and thermostable phase II in the partially purified extract, a difference of one order of magnitude. For the temperature change from 60 to 68°C, the rate constants increased by three orders of magnitude, implying a very high sensitivity (for LPO inactivation in partially purified extract ΔH^?= 646261 J.mole^?1, ΔS^?= 1619 J.mole^?1.K^?1 for phase I, ΔH^?= 546099 J.mole-^l, ΔS^?= 1298 J.mole^?1.K-1^′ for phase II) to heat by both phases, although phase I was clearly the least stable.     

Kigelia africana seed: proximate,mineral, vitamin E,fibre, amino acid and fatty acid composition

Research reports on the ethnomedical and pharmacological potential of Kigelia africana extracts. In this study, the nutritional potential of K. africana seed and seed oil was evaluated by chemical analyses. Organic matter and ash constituted 915.23 ± 7.98 g kg^?1 DM and 49.05 ± 4.55 g kg^?1 DM of the seed mass, respectively. Oil constituted 492.2 g kg^?1 DM of the seed mass with oleic acid, linoleic acid and α‐linolenic acid constituting 17.6%, 12.9% and 54.3%, respectively, of the seed oil. Vitamin E concentration was 0.94 ± 0.25 μg g^?1. Crude protein was 357.35 ± 3.39 g kg^?1 DM. Arginine (6.14 ± 0.31 g per 100 g) as the most abundant amino acid and hydroxyproline (0.11 ± 0.06 g per 100 g) the least. Phosphorus (1123.2 mg per 100 g) and calcium (56.1 mg per 100 g) were, respectively, the most and least abundant minerals. Gross energy was 29.6 ± 0.06 MJ kg^?1. Kigelia africana seeds could be exploited as nutrient‐dense dietary supplement rich in protein, oleic acid and essential fatty acids.     

Thermal Degradation Kinetics of Pyridoxine Hydrochloride in Dehydrated Model Food Systems

The thermal degradation kinetics of pyridoxine hydrochloride were examined using a dehydrated model food system designed to simulate a ready-to-eat breakfast cereal. This study was carried out to provide information useful in estimating the thermal losses of pyridoxine hydrochloride in the processing of breakfast cereals and other low moisture dehydrated food systems. Portions of the model system which were fortified with pyridoxine hydrochloride were toasted in a conduction oven at 155°, 170°, 185°, and 200°C for a minimum of six heating times at each temperature. Pyridoxine (PN) content was determined in the heat treated model systems by high performance liquid chromatography (HPLC). For each heat treatment, the loss of pyridoxine could be described by a first order kinetics model. The first order rate constants for 155°, 170°, 185°, and 200°C were 1.74 × 10^?2 min^?1, 5.22 × 10^?2 min^?1, 16.88 × 10^?2 min^?1, and 48.95 × 10^?2 min^?1, respectively. The calculated Arrhenius activation energy was 29.8 Kcal/mol. In comparing the HPLC method to the standard microbiological assay, the HPLC assay gave lower PN values for the toasted model system. To explain this discrepancy, HPLC fractions were collected and analyzed by the microbiological assay. No significant vitamin B₆ activity was found in any fraction other than that containing the PN peak. It is possible that the milder extraction procedure used in the HPLC assay is less capable of recovering forms of PN which may become bound during the toasting process. These potentially bound forms may or may not be biologically available.     

The effect of pH on the formation of aroma compounds produced by heating a model system containing l-ascorbic acid with l-threonine/l-serine

The identification of aroma compounds, formed from the reactions of l-ascorbic acid with l-threonine/l-serine at five different pH values (5.00, 6.00, 7.00, 8.00, or 9.55) and 143 ± 2 °C for 2 h, was performed using a SPME–GC–MS technique, and further use of LRI. The results showed 35 aroma compounds. The reaction between l-ascorbic acid and l-threonine/l-serine led mainly to the formation of pyrazines. Many of these were alkylpyrazines, such as 2-methylpyrazine, 2,5-dimethylpyrazine, 2-ethylpyrazine, 2-ethyl-6-methylpyrazine, 2-ethyl-5-methylpyrazine, 3-ethyl-2,5-dimethylpyrazine, 2,3-diethyl-5-methylpyrazine, and 3,5-diethyl-2-methylpyrazine; other compounds identified were furans and aldehydes. More volatiles were generated in l-ascorbic acid with l-threonine systems than in l-ascorbic acid with l-serine systems. The studies showed that furans, such as furfural, 2-furanmethanol, benzofuran, 2,5-furandicarboxaldehyde and 2-furfurylfuran were formed mainly at acidic pH. In contrast, higher pH values could promote the production of pyrazines.     

Diffusion of Acetic and Propionic Acids from Chitosan-based Antimicrobial Packaging Films

The diffusion of acetic or propionic acids from thin (44 to 54 μm) chitosan‐based antimicrobial packaging films in which they were incorporated was measured after immersion of the films in water, and the effects of pH (5.7, 6.4, or 7.0) and temperature (4 °C, 10 °C, or 24 °C) on diffusion were investigated. The kinetics of acetic‐ and propionic‐acid release deviated from the Fickian model of diffusion. Diffusion was found to be unaffected by pH in the range of values tested, but a decrease in temperature from 24 °C to 4 °C resulted in a reduction of diffusion coefficients from 2.59 × 10^?12 m².s^?1 to 1.19 × 10^?12 m².s^?1 for acetic acid and from 1.87 × 10^?12 m².s^?1 to 0.91 × 10^?12 m².s^?1 for propionic acid. The effect of temperature on diffusion was well (r² > 0.9785) described by an Arrhenius‐type model with activation energies of 27.19 J.mole^?1 (acetic) and 24.27 J.mole^?1 (propionic). Incorporation of lauric acid or essential oils (cinnamaldehyde or eugenol) into the chitosan film at the time of preparation produced a subsequent reduction in the diffusion of acetic or propionic acid, and maximum effects were obtained with lauric acid and cinnamaldehyde incorporated to final concentrations of 1.0% and 0.5% (w/w), respectively.     

Occurrence of the C-series fumonisins in maize from the former Transkei region of South Africa

Fumonisins are a group of structurally related mycotoxins produced mainly in maize by Fusarium verticillioides and F. proliferatum. The most abundant naturally occurring analogue is fumonisin B₁ (FB₁), with lesser amounts of fumonisin B₂ (FB₂) and fumonisin B₃ (FB₃) occurring. The C-series fumonisins (FCs) are structurally analogous to the B-series but lack the C-1 methyl group. Good and mouldy subsistence-grown maize samples were collected from the Centane and Bizana districts in the former Transkei region of South Africa. After extraction with methanol/water and clean-up on strong anion exchange solid phase extraction cartridges, FB₁, FB₂, FB₃, FC₁, FC₃ and FC₄ were determined by reversed-phase LC–MS/MS using positive ion electrospray ionisation. FB₁ levels in both good and mouldy maize from Centane (means (±SD) 2.75?±?2.24 and 23.4?±?12.5?mg?kg^?1, respectively) were higher than the corresponding levels in maize samples from Bizana (means 0.056?±?0.157 and 3.71?±?5.01?mg?kg^?1, respectively). Similarly, FC₁ levels in both good and mouldy maize from Centane (means 0.107?±?0.099 and 0.814?±?0.391?mg?kg^?1, respectively) were higher than in Bizana, where FC₁ was detected in only one (0.018?mg?kg^?1) of 19 good maize samples and occurred in mouldy maize with a mean of 0.102?±?0.135?mg?kg^?1. A significant correlation (r?=?0.982, p?<?0.01) was observed between FB₁ and FC₁ levels in all samples, with FC₁ levels at 3.3% of the corresponding FB₁ levels. FC₄ levels were similar to FC₁, whereas only low amounts of FC₃ were detected.     

Chemical composition and in vitro antioxidant studies on Syzygium cumini fruit

Syzygium cumini, widely known as Jamun, is a tropical tree that yields purple ovoid fleshy fruit. Its seed has traditionally been used in India for the treatment of diabetes. Based on the available ethno‐pharmacological knowledge, further studies were extended to understand the chemical composition and antioxidant activities of three anatomically distinct parts of fruit: the pulp, kernel and seed coat. Fruit parts, their corresponding ethanol extracts and residues were evaluated for chemical composition. The alcoholic extract was evaluated for its antioxidant potential against DPPH^?, OH^?, O₂^?? and lipid peroxidation. The whole fruit consisted of 666.0 ± 111.0 g kg^?1 pulp, 290.0 ± 40.0 g kg^?1 kernel and 50.0 ± 15.0 g kg^?1 seed coat. Fresh pulp was rich in carbohydrates, protein and minerals. Total fatty matter was not significant in all three parts of fruit. Detailed mineral analysis showed calcium was abundant in all fruit parts and extracts. Total phenolics, anthocyanins and flavonoid contents of pulp were 3.9 ± 0.5, 1.34 ± 0.2 and 0.07 ± 0.04 g kg^?1, respectively. Kernel and seed coat contained 9.0 ± 0.7 and 8.1 ± 0.8 g kg^?1 total phenolics respectively. Jamun pulp ethanol extract (PEE), kernel ethanol extract (KEE) and seed coat ethanol extract (SCEE) showed a high degree of phenolic enrichment. DPPH radical scavenging activity of the samples and standards in descending order was: gallic acid > quercetin > Trolox > KEE > BHT > SCEE > PEE. Superoxide radical scavenging activity (IC₅₀) of KEE was six times higher (85.0 ± 5.0 µg mL^?1) compared to Trolox (540.0 ± 5.0 µg mL^?1) and three times compared to catechin (296.0 ± 11.0 µg mL^?1). Hydroxyl radical scavenging activity (IC₅₀) of KEE was 151.0 ± 5.0 µg mL^?1 which was comparable with catechin (188.0 ± 6.0 µg mL^?1). Inhibition of lipid peroxidation of the extracts was also studied and their activity against peroxide radicals were lower than that of standard compounds (BHT, 79.0 ± 4.0 µg mL^?1; quercetin, 166.0 ± 13.0 µg mL^?1; Trolox, 175.0 ± 4.0 µg mL^?1; PEE, 342.0 ± 17.0 µg mL^?1; KEE, 202.0 ± 13.0 µg mL^?1 and SCEE, 268.0 ± 13.0 µg mL^?1. Copyright © 2007 Society of Chemical Industry     

Evolution of amino acids and biogenic amines in natural ciders as a function of the year and the manufacture steps

The evolution of biogenic amines and other nitrogen compounds during the elaboration period of natural ciders in two successive seasons and two types of presses was studied. The harvest year affects the concentrations of most of the amino acids, while few of them were affected by the type of press. Asparagine and aspartic acid were the most abundant amino acids in fresh musts followed by α‐alanine, α‐aminobutyric acid, glutamine and glutamic acid. The mean concentrations of these amino acids in the fresh musts from the two harvest years were 12.35, 11.12, 6.45, 6.29, 5.28 and 4.87 mg L^?1, respectively. During cidermaking, a decrease in the sum of all amino acids was detected (from 128 ± 54.311 mg L^?1 to 22.5 ± 4.863 mg L^?1 in 2005 and from 72.2 ± 15.256 mg L^?1 to 6.5 ± 4.112 mg L^?1 in 2006). Furthermore, significant differences in the concentration of most amino acids related to harvest year were observed. Concerning the biogenic amine content, putrescine was the main and the only amine present in all musts (3.72 ± 1.68 mg L^?1) and ciders (3.59 ± 1.83 mg L^?1). Histamine was the second biogenic amine of quantitative importance in final ciders (1.15 ± 0.69 mg L^?1), and tyramine was only detected in one of the cidermaker cellars at the end of the elaboration period. The low concentrations of biogenic amines in ciders were attributed to the low contents of the corresponding precursor amino acids and do not affect to cider quality.     

Effect of cellulase/glucanase/xylanase (Roxazyme G2) enzymes combination on nutrients utilisation of vegetable meal (Amaranthus cruentus) fed as sole dietary protein source in rat assay

Amaranthus cruentus vegetable meal (ACVM) had 23% crude protein. Ca, Na, K, Mg and Fe were abundant at 2.0 g kg^?1, 7.1 g kg^?1, 4.8 g kg^?1, 2.5 g kg^?1, 1109 mg kg^?1, respectively. P‐phosporous, oxalates and tannins were noticeable. Lysine, methionine and cystine were limiting. Weight gain for rats on the reference (casein) diet 2 at 6.30 g ±2.87 was highest (P < 0.05) followed by diet 6 (12% ACVM with enzyme supplementation) at 5.01 g ±2.42. Feed intakes were similar (P > 0.05) for rats on the reference diet and for rats on 10% and 12% with/without enzyme supplementation ranging from 42.90 g ± 4.52 in reference diet to 45.12 g ± 3.64. Nitrogen retention was highest for rats on reference diet but similar (P > 0.05) to rats on 12% enzyme supplemented diet at 0.53 ± 1.12 and 0.53 ± 2.10, respectively. Other investigated protein evaluation parameters revealed similar results among rats kept on reference diet and the rats on ACVM based diets with enzyme supplementations. Enzyme supplementation had a complimentary role in ACVM nutrition in rat trial.     

VOLATILE NITROGEN-CONTAINING COMPOUNDS GENERATED FROM MAILLARD REACTIONS UNDER SIMULATED DEEP-FAT FRYING CONDITIONS

A total of 29 volatile nitrogen-containing compounds were identified from model systems containing glutamine, glutamic acid, asparagine and aspartic acid, respectively, with glucose under simulated deep-fat frying conditions in corn oil. Alkylpyrazines were the most important flavor compound generated. Glutamine, which released free ammonia easily under this condition gave the highest yield of alkylpyrazines. The profiles of pyrazines produced by each amino acid were significantly different. In a glutamine system, 2-(2-furyl)pyrazine, 2-(2-furyl)- 5-methylpyrazine and 2-(2-furyl)-6-methylpyrazine were the major compounds generated.     

Characteristics of the leaf parts of some traditional Korean salad plants used for food

BACKGROUND: Total phenolics content, antioxidant activity and cytotoxicity of the methanol extracts from leaf parts of 13 Korean traditional salad plants were investigated in order to determine their properties. RESULTS: The highest phenolics content (mg ferulic acid equivalents kg^?1 dry weight (d.w.), omit one) was found in methanol extracts from Polygonum aviculare, at 293.7 ± 6.0, followed by Euonymus alatus, at 250.7 ± 3.3, Saxifraga stolonifera, at 125.0 ± 8.1 and Ligularia fischeri, at 122.5 ± 5.9. The methanol plant extracts dose‐dependently increased free radical scavenging activity. Methanol extracts of Polygonum aviculare, Euonymus alatus and Saxifraga stolonifera, at 31 mg kg^?1, exhibited the highest 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging activity (%) by 90.8 ± 4.2, 85.7 ± 3.9 and 64.1 ± 3.2, respectively. According to 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay, the methanol extracts from Portulaca oleracea (IC₅₀ < 25.0 µg mL^?1) showed the highest cytotoxicity against Calu‐6, followed by Plantago asiatica (49.2 µg mL^?1) and Osmunda japonica (89.6 µg mL^?1). CONCLUSION: Total phenolics content of the tested plant extracts was correlated with the DPPH radical scavenging activity, suggesting the phenolics compounds are contributing to the antioxidant properties of Korean salad plants. The leaf parts of the 13 Korean traditional salad plants described here that are currently used as foods may also provide some benefit to human health, and research into their potential benefits as preventative and/or therapeutic agents is warranted. Copyright © 2008 Society of Chemical Industry     

Antioxidant and Antihemolytic Activities of Ethanolic Extract of Flowers,Leaves, and Stems of Hyssopus officinalis L. Var. angustifolius

In this study, antioxidant and antihemolytic activities of ethanolic extract of flowers, leaves, and stems of Hyssopus officinalis L. Var. angustifolius were investigated employing different in vitro assay systems. Extracts showed good antioxidant activity. IC₅₀ for 1,1-diphenyl-2-picryl hydrazyl radical-scavenging activity were 148.8 ± 4.31 μg mL^?1 for flowers, 79.9 ± 2.63 μg mL^?1 for stems, and 208.2 ± 6.45 μg mL^?1 for leaves. All extracts showed moderate iron (II) chelating ability. Extracts exhibited good antioxidant activity in the hemoglobin-induced linoleic acid model and also they were capable of scavenging hydrogen peroxide in a concentration dependent manner. Extracts showed good antihemolytic activity againts hydrogen peroxide-induced hemolysis (IC₅₀ were 48.51 ± 2.27 μg mL^?1 for flowers, 19.47 ± 0.73 μg mL^?1 for leaves, and 63.1 ± 2.65 μg mL^?1 for stems). The total amount of phenolic compounds in the extracts was determined as gallic acid equivalents and total flavonoid content was calculated as quercetin equivalents from a calibration curve.     

Effect of heat pasteurisation on some egg white enzymes

It has been shown by a potassium permanganate titration method that solutions of egg white decompose hydrogen peroxide. Using an oxygen electrode the 1st-order rate constants for the decomposition of hydrogen peroxide (during the first minute of the reaction) by different samples of newly laid and laboratory heat-treated egg white, have been calculated. An Arrhenius plot of calculated denaturation constants has shown that the activation enthalpy, free energy and entropy changes required for the heat inactivation of the catalase-like property' were 39.8 kcal mole^?1, 22.6 kcal mole^?1 and 51 entropy units, respectively. The effect of heat on the lyspzyme, the a-mannosidase and the N-acetyl-β-D-glucosaminidase enzymes of egg white has also been studied and it has been shown that the activity of N-acetyl-β-D-glucosaminidase enzyme is reduced by heat at 53 to 57°. The activation enthalpy, free energy and entropy changes required for the heat inactivation of N-acetyl-β-D-glucosaminidase were 62.9 kcal mole^?1, 21.8 kcal mole^?1 and 124.5 entropy units, respectively. The results are discussed with particular reference to the occurrence, disputed by some workers, of a catalase enzyme in egg white, and to a possible application of the effects of heat on the egg white enzymes as a method for measuring the effectiveness of heat pasteurisation processes.     

Use of methylpyrazine ratios to monitor the coffee roasting

The formation of methylpyrazines has been determined in roasted coffee beans (Arabica and Robusta). The determination of different methylpyrazines was studied by the coupled steam distillation-microdistillator as extraction method and gas chromatography using a capillary column and a thermionic detector.

The pyrazine; 2-methyl-; 2,3-dimethyl-; 2,5-dimethyl-; 2,6-dimethyl-; trimethyl- and tetramethyl pyrazine were detected in coffee beans. The principal compound was 2-methylpyrazine. The concentration of the latter pyrazine was more than 2000 μg/100 g of coffee beans depending on the time, the temperature of roasting and the origin of the beans. The correlation of the methylpyrazine quantity with the sensory analysis of the beans has shown the possibility of monitoring the roasting process of coffee beans.     

The catalysis of the N-nitrosation of secondary amines by nitrosophenols

p-Nitrosophenols and the structurally related compounds, p-nitroso-N-alkylanilines and p-nitroso-N-dialkylanilines, have been found to catalyse the N-nitrosation of pyrrolidine and morpholine. The p-nitroso-o-cresol catalysed N-nitrosation of pyrrolidine at pH 5 was found to be first order with respect to each of nitrosocresol, pyrrolidine and nitrite. The third order rate constant for the reaction has a value of 2·08 mole^?2litre²min^?1. The corresponding reaction with morpholine follows similar kinetics and has a third order rate constant of 18·47 mole^?2litre²min^?1. p-Nitroso-o-cresol has no effect on the N-nitrosation of N-methylaniline. A mechanism is proposed in which the nitrosophenol reacts, via its quinonemonoxime tautomer, with nitrous acid (or species in equilibrium with nitrous acid) to produce an intermediate nitrosating agent which under goes attack by the amine to produce the N-nitrosamine and regenerate the catalyst.     

Bifurcaria bifurcata: a key macro‐alga as a source of bioactive compounds and functional ingredients

The aim of this work was to study the proximate composition and the bioactive profile of Bifurcaria bifurcata. It contains 73.31 ± 0.69% of moisture, 8.57 ± 0.11 g per 100 g dry weight (d.w.) of protein, 5.81 ± 0.14 g per 100 g d.w. of lipid content and 30.15 ± 0.00 g per 100 g d.w. of ash. The polyunsaturated fatty acids were the most abundant fatty acid (FA), accounting for 2426.56 mg per 100 g which represents 41.77% of the total FA. The methanolic fraction showed high quantity of polyphenols (220.01 ± 0.010 phloroglucinol equivalents g^?1 extract), DPPH radical reduction capacity (EC₅₀:58.82 μg mL^?1) and oxygen radical absorbent capacity (3151.35 ± 119.33 μmol Trolox equivalents g^?1 extract). The highest antimicrobial effect was observed against Pseudomonas aeruginosa (11.3 ± 1.5 mm) and Saccharomyces cerevisiae (IC₅₀:17.07 μg mL^?1) induced by methanolic and dichloromethane fractions, respectively. Dichloromethane fraction revealed the highest antitumor activity on Caco‐2 and HepG‐2 cells. Bifurcaria bifurcata can be a promising source of bioactive compounds and functional ingredients.     

Determination of Chromium Species in Various Medicinal Plants Consumed in Hatay Region in Turkey

In this study, 22 species of medicinal plants (anise, centaury, chamomile, fennel, flax, green tea, indian hemp, laurel, licorice, linden, marestail, melissa, nettle, oat, red clover, riesenfenchel, rosehip, rosemary, sage, senna tea, yam, yarrow) were taken from five different local herbalists in Hatay. Chromium concentrations were determined by inductively coupled plasma-atomic emission spectroscopy. The highest chromium concentrations were detected in chamomile (4.21 ± 0.18 mg kg^?1), licorice (2.80 ± 0.12 mg kg^?1), melissa (2.71 ± 0.10 mg kg^?1), marestail (2.66 ± 0.10 mg kg^?1), and anise (1.98 ± 0.06 mg kg^?1). Minimal concentrations of chromium were found in riesenfenchel (0.33 ± 0.01 mg kg^?1), red clover (0.37 ± 0.01 mg kg^?1), centaury (0.43 ± 0.01 mg kg^?1), senna tea (0.49 ± 0.01 mg kg^?1), and linden (0.50 ± 0.01 mg kg^?1). Cr(III) and Cr(VI) concentrations in medicinal herbs were found in the range of 0.26–3.12 mg kg^?1 and 0.07–1.09 mg kg^?1, respectively.