Tomáš Vaněk

Accumulation of heavy metals using Sorghum sp.

The essential requirement for the effective phytoremediation is selection of a plant species which should be metal tolerant, with high biomass production and known agronomic techniques. The above mentioned criteria are met by crop plant sorghum (Sorghum bicolor). The response of hydroponically grown S. bicolor plants to cadmium and zinc stress was followed. The impact of metal application on physiological parameters, including changes in chlorophylls contents and antioxidative enzymes activities, was followed during the stress progression. Cadmium and zinc were accumulated primarily in the roots of sorghum plants. However, elevation of metal concentrations in the media promoted their transfer to the shoots. Toxic effects of metals applied at lower concentrations were less serious in the shoots in comparison with their influence to the roots. When applied at higher concentrations, transfer of the metals into the leaves increased, causing growth reduction and leading to Chl loss and metal-induced chlorosis. Moreover, higher metal levels in the roots overcame the quenching capacity of peroxidase and glutathione transferase, which was associated with reduction of their activities. Fortification of antioxidant system by addition of glutathione significantly increased the accumulation of cadmium in the roots as well as in the shoots at the highest cadmium concentration applied.

New approach to the characterisation of petroleum mixtures used in the modelling of separation processes

Characterisation of complex mixtures is a common tool especially in oil processing industry. Characterisation procedures result in experimentally gained characterisation curves, but for the simulation of industrial processes the definition of a substitute mixture is required. Traditionally, a system of pseudocomponents is derived from the True Boiling Point (TBP) characterisation curve, but there are a number of disadvantages, e.g. the physical properties of pseudocomponents must be estimated by unreliable empirical methods. The new approach to the characterisation of complex mixtures is based on representing the original mixture by a system of real components. Such substitute mixture is fully defined, it has a chemical character, and physical properties can be simply retrieved from databases. Utilisation of a substitute mixture of real components in the simulation of crude oil processing proved that the new approach could replace the traditional one in normal boiling temperature ranges where real components are available. Both approaches could be also easily combined.

Phytoremediation of Pharmaceuticals—Preliminary Study

Phytoremediation of selected pharmaceuticals (diclofenac, ibuprofen, and acetaminophen) using Armoracia rusticana and Linum usitatissimum cell cultures and by hydroponically cultivated Lupinus albus, Hordeum vulgaris, and Phragmites australis plants in laboratory conditions is described. During in vitro experiments, the best results for acetaminophen were achieved using Armoracia rusticana hairy root cultures, where 100% of the starting amount was removed from the media during eight days. Total removal of ibuprofen and diclofenac was achieved using a Linum usitatissimum suspension culture after one and six days, respectively. In the hydroponic arrangement, the best results were achieved for Lupinus, where acetaminophen was totally removed from media during two or four days in concentrations of 0.1 or 0.2 mM, respectively. The best effectiveness of ibuprofen removal (50% of starting amount) was found in case of Phragmites. Effectiveness of all tested plants for diclofenac removal was low. The best removal was achieved using Phragmites in the case of 0.2 mM concentration—67% of the starting amount and Hordeum for 0.1 mM starting concentration, 56%.

ACCUMULATION OF HEAVY METALS BY IN VITRO CULTURES OF PLANTS

The aim of the project is to study heavy metals accumulation by the selected plants in both laboratory and field conditions. Within the experiments the aspen (Populus tremula × tremuloides), sunflower (Helianthus annuus) and corn (Zea mays) plants were studied. The reasons for this selection were: a fast growth of these plants, an accumulation capacity and an ability to survive in different types of soils. The study was carried out on the aspen plantlets grown in vitro. The plants were exposed to the aqueous solutions having concentrations 0.1 mM, 0.5 mM of Pb2+ or Ni2+, respectively. The accumulation capacityfor aspen, was about 70% of Pb2+ originally present in the solution. The starting concentration of Pb2+ (0.5 mM) exhibited no negative impact on the growth. Besides in vitro expositions, a pilot-scale phytoremediation experiment was carried out at the polluted industrial area (Zn – 75000 mg/kg), (Pb – 16000 mg/kg), (Cr – 590 mg/kg), (Cd – 90 mg/kg) and (Cu – 1700 mg/kg).

Uranium uptake by hydroponically cultivated crop plants.

Hydroponicaly cultivated plants were grown on medium containing uranium. The appropriate concentrations of uranium for the experiments were selected on the basis of a standard ecotoxicity test. The most sensitive plant species was determined to be Lactuca sativa with an EC(50) value about 0.1mM. Cucumis sativa represented the most resistant plant to uranium (EC(50)=0.71 mM). Therefore, we used the uranium in a concentration range from 0.1 to 1mM. Twenty different plant species were tested in hydroponic solution supplemented by 0.1mM or 0.5mM uranium concentration. The uranium accumulation of these plants varied from 0.16 mg/g DW to 0.011 mg/g DW. The highest uranium uptake was determined for Zea mays and the lowest for Arabidopsis thaliana. The amount of accumulated uranium was strongly influenced by uranium concentration in the cultivation medium. Autoradiography showed that uranium is mainly localized in the root system of the plants tested. Additional experiments demonstrated the possibility of influencing the uranium uptake from the cultivation medium by amendments. Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba up to 2.8 times or 1.9 times, respectively. Phosphate deficiency increased uranium uptake up to 4.5 times or 3.9 times, respectively, by Brassica oleracea and S. alba. In the case of deficiency of iron or presence of cadmium ions we did not find any increase in uranium accumulation.

Study of soil-plant transfer of 226Ra under greenhouse conditions.

A soil-plant transfer study was performed using soil from a former uranium ore processing factory in South Bohemia. We present the results from greenhouse experiments which include estimates of the time required for phytoremediation. The accumulation of (226)Ra by different plant species from a mixture of garden soil and contaminated substrate was extremely variable, ranging from 0.03 to 2.20 Bq (226)Ra/g DW. We found differences in accumulation of (226)Ra between plants from the same genus and between cultivars of the same plant species. The results of (226)Ra accumulation showed a linear relation between concentration of (226)Ra in plants and concentration of (226)Ra in soil mixtures. On the basis of these results we estimated the time required for phytoremediation, but this appears to be too long for practical purposes.

Biotransformation of (−)-limonene using Solanum aviculare and Dioscorea deltoidea immobilized plant cells

The biotransformation course of S-(−)-limonene by Solanum aviculare and Dioscorea deltoidea plant cells was studied using 5 different immobilization methods (entrapment into alginate, carrageenan and pectate gels, binding to polyphenyleneoxide and permeation into polyurethane foam). All techniques, with exception of permeation into pre-formed matrix, affected the product ratio. The main products were cis- and trans-carveol and carvone.

Phytoremediation of Selected Explosives

The phytoremediation of trinitrotoluene (TNT), nitroglycerine (NG) and pentaerytritoltetranitrate (PETN) using in vitrocultures of Rheum palmatum, Saponaria officinalisand Populus simonii were studied. All above mentioned explosives were degradated to less toxic products and finally probably bound to the cell wall or further involved in the metabolism. The formation of trinitrobenzene (TNB) during degradation of TNT which is a product of alternative degradation pathway was found too.

High-performance liquid chromatographic enantiomeric resolution in the ten-vertex carborane series: Comparison of acetyl- and native β-cyclodextrin bonded chiral stationary phases

The HPLC resolution on native and acetyl β-cyclodextrin columns is reported for thirteen enantiomeric pairs of racemates, members of two series of positional isomers in the ten-vertex carborane family, the exo-9-L-arachno-5,6-C2B8H12 (L=NH3, primary or secondary amino group) or exo-6-L-arachno-5,10-C2B8H12 (L=secondary or tertiary amino group). The study of influence of the structural factors on retention, selectivity and resolution of individual compounds is described on both chiral stationary phases (CSPs). The deep differences in enantio-selectivities has been observed for native and acetyl β-cyclodextrin CSPs. Circular dichroism (CD) spectra of exo-9-t-BuNH2-arachno-5,6-C2B8H12 and exo-6-Et3N-arachno-5,10-C2B8H12, members of each series are presented. The CD results indicate the different enantiodiscrimination mechanism on the two CSPs under study.

The health signalling of ornamental traits in the Grey Partridge (Perdix perdix)

AbstractBirds express various secondary ornaments that can indicate individual condition and health. Amongst these, red-coloured carotenoid-based ornaments are supposed to be particularly valuable predictors of individual quality, due to their sensitivity to oxidative stress. Nevertheless, melanin-pigmented traits might also signal health and immune functions. Both types of ornaments may be either skin-based or feather-based, each differing in their dynamics. In the present study, we compared the health- and stress-indicating capacity of melanin-based feather ornamentation and putatively carotenoid-based skin ornamentation in a single species—the Grey Partridge (Perdix perdix), a vulnerable avian species of the European agricultural landscape. In captive males, we firstly verified the carotenoid content of the red-coloured skin tissue behind the eye by chromatography (HPLC). Secondly, we assessed the individual health status of all males by examining differential leukocyte count, the frequency of immature erythrocytes, malaria prevalence and proinflammatory immune responsiveness to phytohaemagglutinin (PHA). Both the size of the melanin-based ornament and red chroma of the carotenoid-based ornament were related to the heterophil:lymphocyte (H/L) ratio. Hence, in the Grey Partridge, both redness of the skin ornament and area of the feather ornament may serve as honest indicators of individual health and long-term stress. However, the two ornamental components were unrelated to each other, and the directions of their association to the H/L ratio were opposite. We therefore propose that, in this species, larger melanin-based feather ornamentation size is linked to higher levels of stress (possibly caused by more intensive social interactions with other males), while the level of expression of the carotenoid-based skin ornamentation more reliably signals actual individual health status. Our results are potentially valuable from the perspective of Grey Partridge conservation efforts, as they indicate a simple method for assessing individual quality in this species.ZusammenfassungOrnamentmerkmale als Signale für den Gesundheitszustand beim Rebhuhn (Perdix perdix) Vögel schmücken diverse sekundäre Merkmale, die die Kondition und den Gesundheitszustand eines Individuums anzeigen können. Aufgrund ihrer Empfindlichkeit gegenüber oxidativem Stress gelten unter diesen rote, auf Karotinen basierende Schmuckmerkmale als besonders wichtig. Dennoch können auch auf Melaninpigment basierte Merkmale Gesundheitszustand und Immunfunktionen signalisieren. Beide Ornamenttypen treten sowohl in der Haut als auch in Federn auf, wo sie sich hinsichtlich der Dynamik unterscheiden. In der vorliegenden Arbeit verglichen wir die Kapazität von melaninbasierten Gefiedermerkmalen und die vermutlich karotinbasierte Hautfärbung hinsichtlich ihrer Gesundheitszustands- und Stressindikation beim Rebhuhn (Perdix perdix), einer gefährdeten Vogelart der europäischen Agrarlandschaft. Von Rebhuhnmännchen aus Gefangenschaft bestimmten wir zunächst mittels Chromatographie (HPLC) den Karotingehalt der rot gefärbten Haut hinter dem Auge. Daraufhin ermittelten wir den individuellen Gesundheitszustand aller Männchen indem wir differenzielles Blutbild, den Anteil unreifer Erythrozyten, Malaria-Prävalenz und die entzündliche Immunantwort auf Phytohämagglutinin (PHA) untersuchten. Sowohl die melaninbasierte Ornamentik, als auch die Rotfärbung der auf Karotin basierten Merkmale waren mit dem Verhältnis Heterophile zu Lymphozyten (H/L) korreliert. Damit können beim Rebhuhn beide Schmuckkomponenten, die Rotintensität der Haut, und Gefiederpartien als ehrliche Indikatoren der individuellen Gesundheit und von Langzeitstress dienen. Allerdings ließ sich kein Korrelation zwischen den beiden Komponenten feststellen, und die Zusammenhänge beider mit dem H/L Verhältnis waren gegenteilig. Wir vermuten daher, dass beim Rebhuhn größere melaninbasierte Gefiederornamente mit höheren Stresswerten in Verbindung stehen (möglicherweise verursacht durch intensivere soziale Interaktionen mit anderen Männchen), wohingegen die Stärke der karotinbasierten Hautornamentik zuverlässiger den individuellen Gesundheitsstatus signalisieren. Unsere Ergebnisse sind potentiell aus der Sicht von Rebhuhnschutzmaßnahmen von Nutzen, da sie eine einfache Methode zur Bestimmung individueller Qualität bei dieser Art aufzeigen.