Phenolic acid and flavonoid diversity in four Eucalyptus species

Fazilet Özlem Albayrak | Yüksel Keleş

The economic importance of Eucalyptus trees is due to their rapid growth and high biomass productivity, as well as the beneficial chemical compounds found in their various tissues. Eucalyptus cultivation is common in the southern part of Turkey, especially in the coastal areas of the Mediterranean. In this study, phenolic acids and flavonoids were analyzed in methanol extracts leaf tissues of four eucalyptus species by HPLC. Fifteen different phenolic compounds were determined in the leaf tissues of the four Eucalyptus species examined. The highest total phenolic amounts were found in E. botryoides (160.56 mg g-1DW), followed by E. tereticornis (66.47 mg g⁻¹ DW) and E. citriodora (64.02 mg g⁻¹ DW). Twelve different compounds were determined in E. botryoides and E. citriodora species, 10 in...

Responses of antioxidant defense system of Helianthus annuus to abscisic acid treatment under drought and waterlogging.

Yüksel Keleş, Serpil Ünyayar

The effect of abscisic acid (ABA) treatment on growth pigments and antioxidant defense system were in vestigated in seedlings of Helianthus annuus (cvs. Nantio F1 and Özde mirbey) subjected to drought and waterlogging stress. In addition, seedlings were sprayed with 10 µM ABA three times every other day. Reltive growth rate (RGR) was significantly reduced in both genotypes under drought stress, however, this growth inhibition was less in ABA-treated plants. Total chlorophyll content increased by drought stress in both gentypes. Ascorbate was not influenced by drought, while α-tocopherol in creased in cv. Nantio F1. Ascorbate and α-tocopherol in creased with drought stress in cv. Özdemirbey. ABA treat ment de creased ascorbate and ß-carotene contents while it increased α-tocopherol and xan...

Isolation and characterization of lytic bacteriophages infecting fish pathogen Vibrio sp. strains

Talaş, Gizem | Coral, Gökhan | Coral, Mutlu Nisa Ünaldı | Yılmaz, Şakir Necat

In this study, bacteria were isolated from infected organs of sea bass (Dicentrarhus labrax) and identified as Vibrio sp. according to 16S rRNA analysis. Four bacteriophages were isolated from seawater samples collected from the coast of Mersin province in Turkey.Vibrio sp. strains were used as hosts for bacteriophage isolation. Bacteriophages inhibit the growth of their hosts; Vibrio sp. K12, Vibrio sp. K11, Vibrio sp. L8, Vibrio sp. L5 which are potential bacterial pathogen of sea bass. Bacteriophages were characterized by Restriction Analysis (RA) and Transmission Electron Microscopy (TEM). Restriction Analysis showed that genomes of bacteriophages LP8, KP12, LP5 and KP11 are double stranded DNAs and the sizes of these genomes are 73, 55, 44 and 23 kb respectively. Only three out of pha...

A new record of potentially ichtyotoxic haptophyte species, Prymnesium parvum f. patelliferum, in the Sea of Marmara during a large-scale mucilage event in June 2021

Eker-Develi, Elif | Tekdal, Dilek

A non-calcifying haptophyte species, Prymnesium parvum f. patelliferum (Green, Hibberd & Pienaar) Larsen, is reported for the first time in the Sea of Marmara from the mucilage event on 11 June 2021. The species was identified with a light microscope and scanning electron microscope. In addition, the 18S rRNA gene was partially sequenced in this study. Amplified gDNA of the expected size was sequenced and analyzed via bioinformatics applications. Results of the analysis vigorously recommended that a 672 bp PCR product was component of a small subunit ribosomal RNA gene sequence. The isolate was named MEUE1, and the partial 18S rRNA sequence of MEUE1 was submitted to the NCBI database (accession number OQ740296). Sequence analysis of isolated culture also verified that it was P. parvum f. p...

The response of phytoplankton assemblages to environmental parameters in the Azad Dam Lake in the west of Iran.

Eker-Develi, Elif

Seasonal variations of phytoplankton abundance, species composition, and their interaction with environmental parameters were investigated in the Azad Dam Lake, in the West of Iran during 2015–2016. Sampling was conducted seasonally at five stations in the lake.Multivariate statistical analyses were carried out to define the abiotic variables influencing phytoplankton community composition. A total of 51 taxa of phytoplankton belonging to six phyla were identified. Bacillariophyta (diatoms) were most diverse with 22 taxa, comprised more than 90%of the total density. Despite the low Shannon–Wiener index (H0) diversity (0.10–1.54), pointing out the dominant density of Bacillariophyta resulted in high water quality. Statistical analysis showed seasonal phytoplankton assemblages differences i...

Marker pigments and carbon biomass of phytoplankton on the northeastern Mediterranean Sea coast

Eker-Develi, Elif

Marker pigments are used to determine taxonomic composition and biomass of microalgae in different oceanic regions. However, sometimes discrepancies are encountered between microscopy and marker pigment based approaches principally because of altering environmental factors influencing diversity of phytoplankton. In the present investigation, marker pigments from HPLC-CHEMTAX analysis concurrent with carbon biomass estimated by microscopy were investigated during 2015–2016 at weekly intervals in the eastern Mediterranean Sea coast. Counting nanoplankton (in particular non-calcifying haptophytes and prasinophytes) in live samples provided a better correlation between microscopy and pigment-based results than in fixed samples. Nanoplankton and picoplankton constituted ~56% of chlorophyll a ba...

New records of haptophyte species from the Northeastern Mediterranean Sea for algal flora of Turkey.

Eker-Develi, Elif

Chrysochromulina alifera, Chrysochromulina lanceolata, Chrysochromulina parkeae, Haptolina cf. ericina, Umbellosphaera irregularis, Umbellosphaera tenuis, Umbilicosphaera foliosa, Syracosphaera molischii, Rhabdosphaera clavigera var stylifera and Ophiaster formosus were recorded for the first time along the Turkish coasts. Non-calcified haptophyte species Chrysochromulina alifera, C. lanceolata, C. parkeae and H. cf. ericina were observed in live samples since formaldehyde damages cells. Among them only C. alifera could be observed with SEM. Either SEM pictures or light microscope images of other species were presented. Although previously reported along Turkish coasts Syracosphaera pulchra was a coccolithophore species most frequently observed after Emiliania huxleyi in the study area. Sc...

The response of phytoplankton assemblages to environmental parameters in the Azad Dam Lake in the west of Iran.

Eker-Develi, Elif

Seasonal variations of phytoplankton abundance, species composition, and their interaction with environmental parameters were investigated in the Azad Dam Lake, in the West of Iran during 2015–2016. Sampling was conducted seasonally at five stations in the lake.Multivariate statistical analyses were carried out to define the abiotic variables influencing phytoplankton community composition. A total of 51 taxa of phytoplankton belonging to six phyla were identified. Bacillariophyta (diatoms) were most diverse with 22 taxa, comprised more than 90%of the total density. Despite the low Shannon–Wiener index (H0) diversity (0.10–1.54), pointing out the dominant density of Bacillariophyta resulted in high water quality. Statistical analysis showed seasonal phytoplankton assemblages differences i...

Thermostable alkaline protease produced by an Aspergillus niger strain

Coral, Mutlu Nisa Ünaldı | Coral, Gökhan

A thermostable alkaline protease was isolated from the Aspergillus niger Z1 strain in a liquid Czapek Dox medium, containing casein (1% w/v) as the sole nitrogen source. Enzyme extract was subjected to electrophoresis in SDS-polyacrylamide gel. Two protein bands were seen on polyacrylamide gel. Active enzyme was visualized in a zymogram and protease activity exhibited a molecular mass of 68 kDa on SDS-polyacrylamide gel. The optimum pH for activity was found to be 9.0. The temperature optima of the enzyme was found to be 40 °C at pH 9.0 and it remained stable up to 90 °C, with 48.4% of the original activity retained after heat treatment at 90 °C for 15 min. Proteolytic activity was inhibited by PMSF, but slightly inhibited by SDS.

Aqueous extract of Acacia cyanophylla leaves as environmentally friendly inhibitor for mild steel corrosion in 1 MH2SO4 solution

Gülşen Avcı, Yüksel Keleş

The efficiency of Acacia cyanophylla leaves extract as an environmentally friendly inhibitor for mild steel in aerated aqueous 1M H2SO4 solution has been investigated by potentiodynamic polarization measurements and electrochemical impedance spectroscopy techniques. Addition of inhibitor decreases the corrosion current whereas the corrosion potential values show slight shifts in positive directions. Inhibition efficiency was found to be about 93% (the maximum value was determined from the polarization curve). Efficiencies obtained from both electrochemical techniques are in good agreement. Adsorption of acacia cyanophylla leaves extracton mild steel surface in 1 M H2SO4 solution obeys Langmuir adsorption isotherm. Polarization curves were also obtained at different temperatures in order to...

Incidence of inducible bacteriophage in Bacillus sp. And Pseudomonas sp. Strains isolated from contaminated soil in Mersin

Coral, Mutlu Nisa Ünaldı

In the current study, the effects of environmental agents on induction of soil lysogenic bacteria were studied. To estimate the prevalence of lysogeny within bacterial communities from contaminated soil, induction assays were carried out by extracting bacteria from soil. A series of experiments were conducted with samples collected in Mersin to assess the impact of some physical and chemical agents on propage induction in natural populations. A total of 90 bacteria were isolated from these sites. UV radiation, temperature, some mutagens and hydrocarbons were used to induce prophage in lysogenic bacteria. Two-thirds of the lysogenic bacteria showed prophage induction by one of the agents. The effects of these agents on the efficiency of plating (EOP) and on the adsorption of lytic bacteriop...

Detection of polycyclic aromatic hydrocarbon (PAH) degradation genes in polluted soil by DNA extraction and colony hybridization

Coral, Gökhan | Coral, Mutlu Nisa Ünaldı

The aim of this study is to detect the DNA sequences for the PAH-dioxygenase gene, the key enzyme of the aeго-bic catabolic for polycyclic aromatic hydrocarbon degra-dation, in soil microorganisms by using extraction of total DNA, PCR amplification PAH-dioxygenase sequences, and detection with colony hybridization. To determine whether bacteria containing PAH-dioxygenase gene actually exist in environments contaminated by crude oil or not, the ge-nomic DNA was purified using a genomic DNA purifica-tion kit. Purified genomic DNA was then amplified with a thermal cycler, and the PCR products were separeted by agarose gel electrophoresis. Pseudomonas sp. strain ARP 26, which is capable of degrading phenanthrene, was used as target for colony hybridization. It was confirmed that Pseudomonas sp...

FEN BİLİMLERİ ÖĞRETMENLERİNİN OKULDIŞI (DOĞA DENEYİMİNE DAYALI) EĞİTİME YÖNELİK GÖRÜŞLERİNİN DEĞERLENDİRİLMESİ

Coral, Mutlu Nisa Ünaldı

Bu çalışmanın amacı Fen Bilimleri Öğretmenlerinin okul dışı (doğa deneyimine dayalı) eğitime yönelik görüşlerini ortaya koymaktır.Araştırmanın çalışma grubunu elverişli örnekleme metoduyla belirlenen 20 fen bilimleri öğretmeni oluşturmaktadır. Veri toplama aracı olarak araştırmacı tarafından hazırlanan ve 6 açık uçlu sorudan oluşan yarı yapılandırılmış görüşme formu kullanılmıştır. Görüşmeler her bir öğretmenle yaklaşık yirmişer dakikalık oturumlar şeklinde gerçekleştirilmiş ve ses kaydı alınmıştır. Ayrıca araştırmacı görüşme boyunca görüşme formu üzerine de notlar almıştır.Elde edilen verilerin dijital ortama aktarılmasının ardından verilere içerik analizi uygulanmış, kodlar ve temalar belirlenmiştir. Elde edilen bu kod ve temalar çerçevesinde öğretmen görüşleri saptanmış ve değerlendiril...

Fen Bilgisi Öğretmenliği Programındaki Alan Derslerinin Mesleki Yeterliliğe Katkısına Yönelik Öğretmen Adayı Görüşleri

Say, Fuat Serkan

GÖKYÜZÜ GÖZLEM YAZILIMI İLE DESTEKLENMİŞ ASTRONOMİ ÖĞRETİMİNİN FEN BİLGİSİ ÖĞRETMEN ADAYLARININ ASTRONOMİ ÖĞRETİMİ ÖZ-YETERLİKLERİNE ETKİSİ

Say, Fuat Serkan

Plasmid mediated heavy metal resistances in Enterobacter spp. isolated from Sofulu landfill, in Adana, Turkey

Coral, Mutlu Nisa Ünaldı | Coral, Gökhan

A total of 15 Enterobacter spp. were isolated from water drainage near the landfill in Sofulu village in Adana and were characterised on the basis of morphological, cultural and biochemical characteristics. The Maximum Tolerable Concentrations of cadmium, copper, chromium and nickel for growth were used to determine metal tolerance of the isolated strains. Among the resistant strains used in this study, Ent-5, Ent-7 and Ent-15 were found to have plasmid resistance to copper and nickel. One resistant strain, Ent-5, functioned as a donor of copper resistance. Copper resistance transferred from Ent-5 to Escherichia coli AB3505 at a frequency of approximetely 2.7 x 10-5 per recipient cell. Transformant strain had one plasmid with the same molecular weight donor strain’s plasmid. These isolates...