Gürcan Güleryüz

Antimicrobial Activity of Three Endemic Verbascum Species

The extracts obtained from three Verbascum L. species (Verbascum olympicum Boiss., Verbascum prusianum Boiss., and Verbascum bombyciferum Boiss.) have been investigated for their antimicrobial activity. Growth inhibition, using the agar disc diffusion assay, was determined against Escherichia coli ATCC 11230, Micrococcus luteus La 2971, Staphylococcus aureus ATCC 6538P, Salmonella thyphi ATCC 19430, Klebsiella pneumoniae UC57, Pseudomonas aeroginosa ATCC 27893, Corynebacterium xerosis CCM 2824, Bacillus cereus ATCC 7064, Bacillus megaterium DSM 32, Mycobacterium smegmatis CCM 2067, Proteus vulgaris ATCC 8427, Candida albicans ATCC 10231, Rhodotorula rubra, and Saccharomyces cerevisiae ATCC 9763. We found that Verbascum L. species showed antimicrobial activity against the Gr(+) bacteria and yeasts, but no activity was seen against the Gr(-) bacteria used in this study.

Element Content (Cu, Fe, Mn, Ni, Pb, and Zn) of the Ruderal Plant Verbascum olympicum Boiss. from East Mediterranean

In this study, heavy metal content (Cu, Fe, Mn, Ni, Pb, Zn) was determined in soils and different organs of Verbascum olympicum Boiss. This species is endemic to Uludağ and spreads on destroyed areas such as: roadsides, developed building areas, ski lift stations and sheep folds. Soils and different organs (roots, stems, leaves and flowers) of plant samples were analyzed using an atomic absorption spectrophotometer for determining the element content. Heavy metal contents in soils and different organs in this species were highly correlated (P < 0.05). However, the contribution of plant organs to the accumulation capacity varied according to the metal. These results suggest that this species may be useful as a bioindicator for heavy metals.

Verbascum bombyciferum Boiss. (Scrophulariaceae) as possible bio-indicator for the assessment of heavy metals in the environment of Bursa, Turkey.

In this study, we determined the heavy metal content (Cd2+, Cr3+, Cu2+, Fe3+, Ni2+, Pb2+, and Zn2+) in the soil surrounding the roots and different organs of Verbascum bombyciferum Boiss. (Scrophulariaceae), which is endemic to Uludağ Mountain, Bursa, Turkey. Plant samples were collected from roadsides, and heavy metal accumulation capabilities were tested. This is one of the pioneer species of ruderal plant communities on roadsides, building sites, rubbish dumps, etc. Different organs of plant samples (roots, stems, leaves, and flowers) and their soils were analyzed by inductively couple plasma optical emission spectroscopy for their heavy metal contents. Some of the analyzed heavy metals (Cd2+, Cr3+, Pb2+, and Zn2+) were usually increased depending on the traffic in the sample sites, and this variation was also reflected in heavy metal content of plant samples. Our results show that this plant can be used as a bio-indicator species in the monitoring of increased Cd2+, Cr3+, Pb2+, and Zn2+ in the environment. We also concluded that V. bombyciferum have the capability of Cd2+, Cr3+, Cu2+, Ni2+, Pb2+, and Zn2+ accumulation.

Protein Mobilization and Proteolytic Enzyme Activities during Seed Germination of Broad Bean (Vicia faba L.)

The protein mobilization from attached and detached seeds of Vicia faba L. cv. Eresen 87 (Fabaceae) was investigated. While the total soluble protein content decreased, the free amino acid content increased during the 7 days germination period. Among the three proteolytic enzymes, only endopeptidase activity was found to be affected by the removal of the embryonic axis. Leucine aminopeptidase activity was high at the beginning, then it decreased; carboxypeptidase activity reached the highest value at day 5. In order to examine the effects of plant growth regulators on detached cotyledons incubated with plant growth regulators [10−4 ᴍ benzyladenine (BA), gibberellic acid (GA3), indole acetic acid (IAA) and 10−5 ᴍ abscisic acid (ABA)], only benzyladenine was found promotive on protein mobilization. Our results suggest that the removal of the embryonic axis in seeds of Vicia faba L. cv. Eresen 87 decreases protein mobilization and endopeptidase activity.

Ni-induced Changes in Nitrate Assimilation and Antioxidant Metabolism of Verbascum olympicum Boiss.: Could the Plant be Useful for Phytoremediation or/and Restoration Purposes?

Verbascum olympicum Boiss. (Scrophulariaceae) were studied as a candidate plant for remediating the Ni polluted soils. The metabolic responses, such as nitrate assimilation (nitrate reductase and glutamine synthetase activity) and antioxidant system activity [superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) activity], of this species exposed to nickel in Hoaglands nutrient medium were investigated as remediation performance parameters. The accumulation of nickel and the variations in the content of some elements (B, Cu, Fe, Mg, Mn, Mo and Zn) and some growth parameters, such as the water content, biomass production, and contents of chlorophyll and soluble protein, were also examined. The accumulation of Ni in both the roots and leaves varied depending on the exposure times and doses. Increased oxidative stress was suggested by the increases in the activities of SOD, CAT and APX. Although some element contents were inhibited by Ni treatments, these inhibitory effects was decreased depending on the time, and even these elements are accumulated in roots. These results are the novelties in the use of this species in biotechnology.

Variation in trace element mobility and nitrogen metabolism of Verbascum olympicum Boiss. under copper stress

The aim of this study was to evaluate the effects of copper (Cu) stress on accumulation and transport of trace elements, nitrogen assimilation, and growth parameters of Verbascum olympicum. Eight-week-old seedlings were grown in Hoaglands solution and exposed to 0, 50, 250, or 500 µM CuSO4 for seven days in laboratory conditions. Bioaccumulation of trace elements (boron, bismuth, cobalt, Cu, iron, lithium, manganese, molybdenum, nickel, lead, zinc) in the roots and leaves was determined by inductively coupled plasma–mass spectrometry after one, three, and seven days. Chlorophyll content, nitrate reductase, and glutamine synthetase activities, soluble protein content, and biomass were determined. Copper accumulated in the roots and leaves (up to 19609.8 and 256.2 mg kg−1 dry weight, respectively). Other trace elements accumulated to higher levels in the roots of Cu-treated plants compared with those of control plants. High Cu concentrations decreased nitrogen-assimilatory enzyme activities. Compared with control plants, those treated with high Cu concentrations showed lower chlorophyll contents, total protein contents, and biomass. Nitrogen assimilation and growth parameters of V. olympicum were negatively affected by Cu treatment but mineral nutrition was not severely disrupted. The results support the suitability of V. olympicum as a candidate for phytoremediation of Cu-contaminated soils.

Assessment of Trace Elements in Plantago holosteum Scop. (Plantaginaceae) from Abandoned Tungsten Mine Works Using Inductively Coupled Plasma–Mass Spectrometry

ABSTRACT The influence of tungsten on the uptake and translocation of essential elements (B, Bi, Cd, Co, Cr, Cu, Fe, Mn, Mo, Pb, Zn, and W) of Plantago holosteum around the abandoned tungsten mine works on Uludağ Mountain, Turkey was evaluated. Open-wet and Kjeldahl digestion procedures were applied to the samples before elements were determined by inductively coupled plasma–mass spectrometry. Accuracy was evaluated using standard tea and spinach leaf and soil-certified reference materials. The novel approach of this work identified P. holosteum as a possible candidate bioaccumulator species, which was widespread in the tungsten mining area and provided overall, realistic evaluations for many elements, particularly W. Thus, the specific behavior of the selected species separated this species from the others in this damaged ecosystem. The W concentrations in soils and plants were in the range from 6 to 2591 mg kg−1 dry weight and 0.6 to 85.3 mg kg−1 dry weight, respectively. The concentrations of elements in soil samples from the waste removal pool were higher than those from the unpolluted sites, and all elements except manganese increased in plant samples.

Antioxidative defense mechanism of the ruderal Verbascum olympicum Boiss. against copper (Cu)-induced stress

Abstract The endemic Verbascum olympicum has characteristics that allows it to live in degraded areas of Uludağ Mountain, Turkey and therefore known as a ruderal species. In this study, V. olympicum seeds collected from Uludağ Mountain were grown in the Hoagland nutrient solution, under hydroponic conditions. The activity of antioxidative enzymes (superoxide dismutase, SOD; catalase, CAT; ascorbate peroxidase, APX) were examined to demonstrate the role of antioxidative mechanism in the seedlings exposed to different Cu concentrations (0, 50, 250, 500 μM) for seven days. Also, certain growth parameters (such as the water content, biomass production, soluble protein), the level of lipid peroxidation, cell membrane injury and permeability were investigated. As a result, some toxic effects are observed following the application of 500 μM Cu, after the seedlings growing in 50 and 250 mM Cu concentrations showed high resistance and survived in hydroponic conditions. Our findings provide information about the resistance of V. Olympicum seedlings to oxidative stress caused by excessive Cu concentrations.

Germination Responses to GA3 and Stratification of Threatened Festuca L. Species from Eastern Mediterranean

The seed germination characteristics of three threatened Festuca sp. [F. punctoria Sm., F. cyllenica Boiss. et Heldr. subsp. uluana Markgr.-Dannenb., F. paphlagonica (St.-Yves) Markgr.-Dannenb. subsp. paphlagonica] were investigated. These species are endemic and spread on alpine belt. The study was carried out with wet-cold and dry-cold stratification throughout 15 days, different doses of GA3 (50, 100 and 150 ppm) and hormone-stratification combined treatments, and non-treatment series. We found that the germination rates of three fescue seeds for various treatment series were different. The mean germination percentage of F. cyllenica was higher (80%) than that of F. punctoria and F. paphlagonica which were fairly low (50-60%). Germination rates increased by wet-stratification treatment in F. punctoria and also increased with 100 ppm GA3 application to the seeds of F. paphlagonica. When taken into consideration the germination percentages of all fescue species, the seeds of F. punctoria and F. paphlagonica can be dormant, but the seeds of F. cyllenica are non-dormant.