Many contaminated soils contain several toxic elements (TEs) in elevated contents, and plant-TE interactions can differ from single TE contamination. Therefore, this study investigated the impact of combined contamination (As, Cd, Pb, Zn) on the physiological and metabolic processes of lettuce. After 45 days of exposure, TE excess in soil resulted in the inhibition of root and leaf biomass by 40 and 48%, respectively. Oxidative stress by TE accumulation was indicated by markers-malondialdehyde and 5-methylcytosine-and visible symptoms of toxicity (leaf chlorosis, root browning) and morpho-anatomical changes, which were related to the change in water regime (water potential decrease). An analysis of free amino acids (AAs) indicated that TEs disturbed N and C metabolism, especially in leaves, increasing the total content of free AAs and their families. Stress-induced senescence by TEs suggested changes in gas exchange parameters (increase in transpiration rate, stomatal conductance, and intercellular CO2 concentration), photosynthetic pigments (decrease in chlorophylls and carotenoids), a decrease in water use efficiency, and the maximum quantum yield of photosystem II. These results confirmed that the toxicity of combined contamination significantly affected the processes of lettuce by damaging the antioxidant system and expressing higher leaf sensitivity to TE multicontamination.

• Klíčová slova
• anthropogenic contamination, bioaccumulation, metals/metalloids, nitrogen metabolism, oxidative stress, stress response,
• Publikační typ
• časopisecké články MeSH

Halophytes are plant species widely distributed in saline habitats, such as beaches, postindustrial wastelands, irrigated lands, salt flats, and others. Excessive salt level, known to limit plant growth, is not harmful to halophytes, which have developed a variety of defense mechanisms allowing them to colonize harsh environments. Plants under stress are known to respond with several morpho-anatomical adaptations, but also to enhance the production of secondary metabolites to better cope with difficult conditions. Owing to these adaptations, halophytes are an interesting group of undemanding plants with a high potential for application in the food and pharmaceutical industries. Therefore, this review aims to present the characteristics of halophytes, describe changes in their gene expression, and discuss their synthesized metabolites of pharmacognostic and pharmacological significance. Lobularia maritima is characterized as a widely spread halophyte that has been shown to exhibit various pharmacological properties in vitro and in vivo. It is concluded that halophytes may become important sources of natural products for the treatment of various ailments and for supplementing the human diet with necessary non-nutrients and minerals. However, extensive studies are needed to deepen the knowledge of their biological potential in vivo, so that they can be introduced to the pharmaceutical and food industries.

• Klíčová slova
• Lobularia maritima, biopotential, halophyte, molecular mechanisms, phytochemicals, stress genes,
• MeSH
• Brassicaceae * metabolismus   MeSH
• chlorid sodný farmakologie   MeSH
• fyziologická adaptace MeSH
• halotolerantní rostliny * genetika   MeSH
• lidé MeSH
• vývoj rostlin MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• chlorid sodný MeSH

Arsenic is a ubiquitous toxic element that can be accumulated into plant parts. The present study investigated the response of Pteris cretica and Spinacia oleracea to As treatment through the analysis of selected physiological and metabolic parameters. Plants were grown in pots in As(V) spiked soil (20 and 100 mg/kg). Plants' physiological condition was estimated through the determination of elements, gas-exchange parameters, chlorophyll fluorescence, water potential, photosynthetic pigments, and free amino acid content. The results confirmed differing As accumulation in plants, as well as in shoots and roots, which indicated that P. cretica is an As-hyperaccumulator and that S. oleracea is an As-root excluder. Variations in physiological and metabolic parameters were observed among As treatments. Overall, the results revealed a significant effect of 100 mg/kg As treatment on the analysed parameters. In both plants, this treatment affected growth, N, Mg, S, Mn, and Zn content, as well as net photosynthetic rate, chlorophyll fluorescence, and total free amino acid content. In conclusion, the results reflect the similarity between P. cretica and S. oleracea in some aspects of plants' response to As treatment, while physiological and metabolic parameter changes related to As treatments indicate the higher sensitivity of S. oleracea.

• Klíčová slova
• abiotic stress, amaranthaceae family, arsenic contamination, fern, metalloid, pteridaceae family, spinach,
• Publikační typ
• časopisecké články MeSH

Cadmium (Cd) toxicity affects numerous metabolic processes in plants. In the presence of Cd, plants accumulate specific amino acids which may be beneficial to developing Cd tolerance. Our study aimed to characterize the changes in the metabolism of selected free amino acids that are associated with Cd tolerance, and investigate the levels of selected microelements in order to relate these changes to the adaptation strategies of two metallophytes-Noccaea caerulescens (Redlschlag, Austria) and Noccaea praecox (Mežica, Slovenia). The plants were exposed to Cd contamination (90 mg Cd/kg soil) for 120 days in a pot experiment. Our results showed higher Cd accumulation in N. praecox compared to N. caerulescens. Cadmium contamination reduced the zinc and nickel levels in both species and a mixed effect was determined for copper and manganese content. Differences in free amino acid metabolism were observed between the two metallophytes growing under Cd-free and Cd-loaded conditions. Under Cd-free conditions, aromatic amino acids (phenylalanine, tryptophan and tyrosine) and branched-chain amino acids (leucine, isoleucine and valine) were accumulated more in the leaves of N. praecox than in N. caerulescens. Cd stress increased the content of these amino acids in both species but this increase was significant only in N. caerulescens leaves. Marked differences in the responses of the two species to Cd stress were shown for alanine, phenylalanine, threonine and sarcosine. Cadmium contamination also induced an increase of threonine as alanine and sarcosine decrease, which was larger in N. caerulescens than in N. praecox. All these factors contribute to the higher adaptation of N. praecox to Cd stress.

• MeSH
• aminokyseliny metabolismus   MeSH
• Brassicaceae klasifikace   účinky léků   růst a vývoj   metabolismus   MeSH
• fyziologický stres účinky léků   MeSH
• kadmium toxicita   MeSH
• listy rostlin účinky léků   růst a vývoj   metabolismus   MeSH
• metabolické sítě a dráhy účinky léků   MeSH
• sarkosin metabolismus   MeSH
• stopové prvky metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• aminokyseliny MeSH
• kadmium MeSH
• sarkosin MeSH
• stopové prvky MeSH

BACKGROUND: Many areas throughout the world are simultaneously contaminated by high concentrations of soluble salts and by high concentrations of heavy metals that constitute a serious threat to human health. The use of plants to extract or stabilize pollutants is an interesting alternative to classical expensive decontamination procedures. However, suitable plant species still need to be identified for reclamation of substrates presenting a high electrical conductivity. SCOPE: Halophytic plant species are able to cope with several abiotic constraints occurring simultaneously in their natural environment. This review considers their putative interest for remediation of polluted soil in relation to their ability to sequester absorbed toxic ions in trichomes or vacuoles, to perform efficient osmotic adjustment and to limit the deleterious impact of oxidative stress. These physiological adaptations are considered in relation to the impact of salt on heavy metal bioavailabilty in two types of ecosystem: (1) salt marshes and mangroves, and (2) mine tailings in semi-arid areas. CONCLUSIONS: Numerous halophytes exhibit a high level of heavy metal accumulation and external NaCl may directly influence heavy metal speciation and absorption rate. Maintenance of biomass production and plant water status makes some halophytes promising candidates for further management of heavy-metal-polluted areas in both saline and non-saline environments.

• Klíčová slova
• Antioxidants, ROS scavenging, glycinebetaine, halophytes, metal distribution, metallothioneins, mucilage, osmoprotectants, phytochelatins, phytoextraction, phytoremediation, phytostabilization, salt marsh species,
• MeSH
• biodegradace MeSH
• chlorid sodný metabolismus   MeSH
• halotolerantní rostliny metabolismus   MeSH
• hornictví MeSH
• látky znečišťující půdu metabolismus   MeSH
• mokřady MeSH
• pouštní klima MeSH
• regenerace a remediace životního prostředí * MeSH
• těžké kovy metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• chlorid sodný MeSH
• látky znečišťující půdu MeSH
• těžké kovy MeSH