Publications

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    ABSTRACT: ABSTRACT:The purpose of this project was to investigate the total protein, sugar and phenolic content in phosphate extracts of marine macroalgae species from the Aegean Sea. Colpomenia sinuosa (Mertens ex Roth) Derbès & Solier, Petalonia fascia (O.F. Müller) Kuntze, Scytosiphon lomentaria (Lyngbye) Link., Dilophus spiralis (Montagne) G. Hamel, and Padina pavonia J.V. Lamouroux were collected from Izmir Bay during April, as well as Cystoseira sp. collected on the Urla, Bodrum, Fethiye and Kas coastlines during the spring and summer months. The phenolic content of five brown algae extracts varied from 2.5 mg to 21.8 mg GAE/10 g. Dilophus spiralis extracts demonstrated the lowest concentrations based on total protein assay, while Scytosiphon lomentaria extracts showed the highest sugar contents. The extract of Cystoseira sp. collected from Fethiye and Kas, gave the highest concentrations in May.
    Botanica Marina 06/2012; 36(2):91-95. · 0.91 Impact Factor
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    ABSTRACT: The biological activities of Laurencia obtusa and Laurencia obtusa var. pyramidata from Cesme coasts (Turkey) were screened by using in vitro methods. The essential oils of L. obtusa and L. obtusa var. pyramidata were obtained by steam distillation and their chemical compositions were analyzed by GC/MS. The antimicrobial activities against bacteria (two specific pathogenic strains (methicillin-oxacillin resistant Staphylococcus aureus ATCC 43300, hemorrhagic Escherichia coli (O157: H7) RSSK 232)) and one yeast strain (Candida albicans ATCC 10239) were determined by using the disc-diffusion technique. The antimicrobial potential of the L. obtusa essential oil was found considerably strong. It showed inhibitory effect on two bacteria and one yeast strain. The hexane and chloroform extracts of L. obtusa and the methanol and chloroform extracts of L. obtusa var. pyramidata were generally found as moderate antioxidants in comparison with butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA) and α-tocopherol (Vitamin E). The chloroform extracts of both the red algae have high phenolic content compared to the other extracts and essential oils.
    Roumanian biotechnological letters. 01/2011; 16(1):5927-5936.
  • Current Opinion in Biotechnology - CURR OPIN BIOTECHNOL. 01/2011; 22.
  • Dilek Unal, Nuray O. Isik, Atakan Sukatar
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    ABSTRACT: In order to contribute to understanding of the response to metal stress, Ramalina farinacea (L.) Ach. was treated with different concentrations of chromium (VI) (5, 15, and 30 mM of K2CrO4) for 1, 3, and 24 h, and alterations in the photosystem II photosynthetic quantum yield, pigment content, integrity of chlorophyll, cell viability, and proline accumulation were investigated. Significant alterations of the photosynthetic quantum yield (F v/F m) ratio were observed in response to the increase in chromium concentration. The F v/F m ratio decreased in R. farinacea following 24-h treatment with 30 mM Cr6+ solution. In present study, in both control and other plant groups treated with 5 mM Cr6+, the Chl a/b ratio was approximately within the range of 2.0–3.5. However, this ratio significantly decreased for the samples treated with 15 (exposure period of 24 h) and 30 mM; (exposure periods of 3 and 24 h) Cr6+. We also showed that cell viability of samples treated with 15 and 30 mM Cr6+ significantly decreased. Accumulation of metal resulted in proline accumulation in R. farinacea thalli; however, when photodestructive effects on photosystem II occurred, proline intracellular concentration declined. On the basis of these results, we suggest that proline accumulation might not be the stress marker during heavy metal stress. Key words Ramalina farinacea -chromium (VI)-photosynthesis-proline accumulation-lichen
    Russian Journal of Plant Physiology 01/2010; 57(5):664-669. · 0.62 Impact Factor
  • Esra Ersoy Omeroglu, Ismail Karaboz1 and Atakan Sukatar
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    ABSTRACT: Some Vibrio strains are pathogenic and cause vibriosis, a serious infectious disease in maricultured organisms, and in recent years, Vibrio harveyi has been described to be pathogenic to children with cancer. Bioluminescent V. harveyi TEMO5 and TEMS1 were isolated from intestine contents of Holothuria tubulosa and seawater of Izmir Gulf (Turkey) for the first time. Hence, in this study, susceptibility patterns of 21 different antibiotics against these isolates were investigated by agar disc diffusion and micro-dilution method. The findings indicate that while these isolates were resistant to β-lactam antibiotics (ampicillin, cephalothin and cephazolin) and very sensitive to aminoglycoside antibiotics (tobramycin and gentamicin), sulphamethoxazole/ trimethoprim and chloramphenicol, they were resistant to amoxicillin- clavulanic acid inhibiting β-lactamases. Therefore, V. harveyi TEMO5 and TEMS1 are likely to acquire resistance by maintaining in response to natural environmental selection, or changing the permeability of outer membrane anion (porin) channels, or at chromosomal level.
    Fresenius Environmental Bulletin 05/2009; 18(11):2023-2028. · 0.64 Impact Factor
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    ABSTRACT: Macroalgae are rich sources of natural bioactive products. Their secondary metabolites are attracted attends in many fields of life i.e., food, animal feeding, textile, cosmetics, medicine etc. In this study, methanol, dichloromethane and hexane extracts of Codium fragile (Chlorophyta) were tested for antimicrobial and antioxidant activities. Antioxidant effects were evaluated by hydroxyl radical scavenging assay (deoxyribose degradation assay) and b-carotene bleaching assay. The extracts indicated relatively little antioxidant activities, as compared to commercial antioxidants. The composition of the essential oil of C. fragile was also analyzed by GC and GC-MS. Twenty four compounds were identified of C. fragile essential oil and n-tricosane (11.88%) was determined as major component. Essential oil of C. fragile showed weak antibacterial activity against all gram positive bacteria tested, except methicillin-oxacillin resistant Staphylococcus aureus ATCC 43300. Similarly, all the extracts of C. fragile showed weak antimicrobial activity on tested organisms.
    Asian Journal of Chemistry 01/2009; 21(2):1197-1209. · 0.25 Impact Factor
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    ABSTRACT: The present study was conducted to evaluate the antioxidant and antimicrobial activity of methanol, dichloromethane and hexane extracts, as well as the essential oils of brown algae (Phaeophyta) Colpomenia sinuosa, Dictyota dichotoma, Dictyota dichotoma var. implexa, Petalonia fascia and Scytosiphon lomentaria. The essential oil of the macroalgae was obtained by steam distillation and analyzed by GC and GC/MS. The antioxidant activity of the algal extracts was determined using the procedures of inhibition of b-carotene bleaching and ABTS+ methods. The antioxidant effects of the extracts were compared with those of commercial antioxidants, such as butylated hydroxytoluene (BHT), butylated hydroxyanisol (BHA) and a-tocopherol. The hexane extracts of D. dichofoma var. implexa had a higher phenolic content than the other extracts. The dichloromethane extract of S. lomentaria was found to be more active in the decolorization of ABTS+ than the other extracts and generally the dichloromethane extracts were more active than the methanol and hexane extracts. Antimicrobial activities of the extracts were assessed against Gram (+) and Gram (–) bacteria and one yeast strain by the disk diffusion method. According to the re¬sults, the dichloromethane extracts generally showed more potent antimicro¬bial activity than the methanol and hexane extracts at concentrations 1.5 and 1.0 mg/disk.
    Journal of the Serbian Chemical Society. 01/2009;
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    ABSTRACT: In the present study, Physcia semipinnata samples were exposed to UV-A (352 nm) in 20 J m(-2) for 24 h, 48 h and 72 h to seek the alterations in the PSII photosynthetic quantum yield, thallus anatomy and DNA mutation rate in response to radiation. The Fv/Fm ratio decreased in P. semipinnata following exposure to UV-A for 24h, 48 h and 72 h. The data of the present study reported that Chla degradation occurred by exposition of UV-A for 24 h, 48 h and 72 h. Photobiont size and thickness of upper cortex layer also showed a gradually decrease in P. semipinnata thallus sections during 24 h, 48 h and 72 h. The thickness of the upper cortex layer, exposed to UV-A for 72 h, of P. semipinnata thallus reduced 64%, compared with control. The random amplified polymorphic DNA (RAPD) technique was used to detect DNA damage. The main changes observed in the RAPD profiles resulted in both appearance and disappearance of different bands and variation of their intensity. According to RAPD assay, the genetic distance between the control group and 24h , 48 h and 72 h UV-A exposed, groups was found 56%, 78% and 84%, respectively.
    Journal of Photochemistry and Photobiology B Biology 11/2008; 94(1):71-6. · 3.11 Impact Factor
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    ABSTRACT: The methanol, dichloromethane, hexane, chloroform, and volatile components of Dictyopteris membranaceae. (Stackhouse) Batters (Dictyotaceae) and Cystoseira barbata. (Good et Woodw.) J. Agardh (Cystoseiraceae) were tested for their antimicrobial activities (four Gram-positive bacteria, four Gram-negative bacteria, and Candida albicans. ATCC 10239). Five compounds were identified in the volatile oil of D. membranaceae. accounting for >85% of the composition of the volatile oil. Twenty-eight compounds were identified in the volatile oil of C. barbata. accounting for >67% of the composition of the volatile oil. Major components were 6-butyl-1,4-cycloheptadiene (43.21%) for D. membranaceae. and docosane (7.61%) and tetratriacontane (7.47%) for C. barbata.. Many compounds in the volatile oil of C. barbata. were identified as hydrocarbon compounds. The volatile oils of these algae did not remarkably inhibit the growth of tested microorganisms. However, the hexane extracts showed more potent antimicrobial activity than methanol, dichloromethane, and chloroform extracts.
    10/2008; 44(3):183-188.
  • Dilek Unal, Inci Tuney, Atakan Sukatar
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    ABSTRACT: Physcia semipinnata was exposed to UV-A (352nm) and visible light (210, 800 and 2000mW/cm2) for 30min, 1, 2, 24, and 48h to seek the alterations in the PSII photosynthetic quantum yield, in response to radiation. Chlorophyll a fluorescence did not influence exposure to light, 210, 800 and 2000mW/cm2. Significant alterations of the photosynthetic quantum yield ratio occurred in response to increase in UV-A exposure time. The photosynthetic quantum yield ratio decreased in P. semipinnata following exposure to UV-A for 24 and 48h. The thalli of P. semipinnata treated with 1mM polyamine were not influenced during the exposure to UV-A for 24 and 48h. It was also found that exogenously spd added samples had higher chla content than spm and put added samples. In this study, we showed that lipid peroxidation levels between UV-A-treated samples and exogenously polyamine treated samples that were previously exposed to UV-A for 24 and 48h were significantly decreased. This result is the first record to indicate that external polyamines might have some protective role on photosystem II and membrane against UV-A stress.
    Journal of Photochemistry and Photobiology B Biology 02/2008; 90(1):64-8. · 3.11 Impact Factor
  • D. Unal, A. Senkardesler, A. Sukatar
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    ABSTRACT: The levels of endogenous abscisic acid and total polyamine contents (putrescine and spermidine) were studied in two lichen species differing in desiccation tolerance. ABA and polyamine contents showed significant differences between air-dried and water-treated thalli of Pseudevernia furfuracea and Ramalina farinacea. The levels of putrescine (put) and spermidine (spd) in water-treated P. furfuracea thalli were found higher than in dry samples. The values for spd were almost threefold and for put almost 1.4-fold higher than in airdried samples. The levels of put and spd in water-treated R. farinacea were lower than in the air-dried samples. The lowest values for spd and put were almost 33-fold and 2.8-fold less, respectively. ABA contents of water-treated P. furfuracea and R. farinacea increased by 2.65% and 25.5% when compared with air-dried thallus. Key wordsPseudevernia furfuracea–Ramalina farinacea–abscisic acid–desiccation–lichens–polyamines–rehydration
    Russian Journal of Plant Physiology 01/2008; 55(1):115-118. · 0.62 Impact Factor
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    ABSTRACT: Luminous bacteria were isolated from invertebrates and coastal seawater samples in the summer season 2004, from Izmir Gulf in Turkey. The seawater samples were concentrated by using 0.22-μ pore-sized nitrocellulose membrane filters. The concentrated seawater samples and intestinal contents of Holothuria tubulosa were inoculated on Seawater Complete (SWC) and BOSS media. The agar plates were incubated at 25 °C for 48 h. After incubation, bioluminescent bacteria were isolated in a dark room, then purified and stored on a suitable medium. Bioluminescent isolates were identified with a polyphasic approach by using morphological, cultural, biochemical and molecular characteristics, in addition to 16SrDNA sequencing. Finally, the bioluminescent marine bacteria isolated from intestinal contents of H. tubulosa and seawater samples were identified as Vibrio harveyi TEM S1 and TEM O5 strains, respectively.
    Fresenius Environmental Bulletin 12/2007; 17(5):506-510. · 0.64 Impact Factor
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    ABSTRACT: The methanol, dichloromethane, hexane, chloroform and volatile oil extracts of the red alga Jania rubens were tested in vitro for their antimicrobial activity (five Gram-positive, four Gram-negative bacteria and Candida albicans ATCC 10239). GC-MS analysis of the volatile components of J. rubens identified 40 compounds which constituted 77.53% of the total. The volatile components of J. rubens consisted of n-docosane (6.35%), n-eicosane (5.77%) and n-tetratriacontane (5.58%) as major components. The methanol and chloroform extracts (4 mg/disc) showed more potent antimicrobial activity than the hexane and dichloromethane extracts and the volatile oil of J. rubens.
    Phytotherapy Research 03/2007; 21(2):153-6. · 2.07 Impact Factor
  • Inci Tuney, Atakan Sukatar
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    ABSTRACT: Prototheca is an aerobic, achlorophilic and unicellular organism with ovoid shape; it is often confused with yeasts. Prototheca cells are fairly common in a variety of enviroments such as sewage, freshwater, soil, rotting leaves, faeces, skin and various mammals (deer, cat, dog, cattle and humans). Prototheca species are widespread in housing areas, pens and pastures used by dairy cattle and can cause mastitis in dairy cattle. Protothecosis is an uncommon infection of humans and animals. Most infections are clinical and remain as chronic infections. Five species of Prototheca have been identified: P. moriformas, P. stagnora, P. ulmea, P. wickerhamii, P. zopfii; only the last two of these cause infection in humans and animals. Little is known about the ecology of Prototheca. Failure to isolate Prototheca spp. may be explained by the fact that they are readly over-grown by bacteria and fungi when culture is attemped from contaminated sources, as well as the fact that they superficially resemble yeasts. For this reason a specific culture media has been developed for Prototheca spp.
    Reviews in Medical Microbiology 07/2006; 17(3):77-82. · 0.36 Impact Factor
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    ABSTRACT: The methanol, dichloromethane, hexane, chloroform and volatile components ofEnteromorpha linza were testedin vitro for their antimicrobial activity against five Gram-positive, four Gram-negative bacteria andCandida albicans ATCC 10239. GC-MS analysis of the volatile components ofE. linza resulted in the identification of 35 compounds which constituted 84.76% of the total compounds. The volatile components ofE. linza consisted of n-tetratriacontane (8.45%), 1-heptadecanamine (6.65%) and docosane (6.46%) as major components. The methanol and chloroform extracts showed more potent antimicrobial activity than hexane and dichloromethane extracts. The volatile oils of these algae did not remarkably inhibit the growth of tested microorganisms.
    Annals of Microbiology 01/2006; 56(3):275-279. · 1.55 Impact Factor
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    ABSTRACT: We surveyed the epizoic algae growing on Emys orbicularis from several sites in the Central Anatolia region of Turkey during the nesting season (May-August) of 2005. Fifty-three algae species were found on carapaces of thirty-five E. Orbicularis, with considerable variation in the algal communities from different sites.
    Journal of Freshwater Ecology - J FRESHWATER ECOL. 01/2006; 21(3):535-538.
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    ABSTRACT: Biosorption of Cr6+ from aqueous solution on dried (Halimeda tuna, Sargassum vulgare, Pterocladia capillacea, Hypnea musciformis, Laurencia papillosa) algae were studied with variation in the parameters of pH, initial metal ion concentration and agitation time. From the batch system studies the working sorption pH value was determined as 1.0 for Halimeda tuna and Sargassum vulgare, 2.0 for Pterocladia capillacea and Hypnea musciformis, 3.0 for Laurencia papillosa. The total adsorbed quantities, equilibrium uptakes and total removal percents of Cr6+ were determined by evaluating the breakthrough curves obtained at different inlet Cr6+ concentration for each sorbent. The maximum chromium biosorption occured at 120 min for Halimeda tuna, 180 min for Sargassum vulgare, Hypnea musciformis and Pterocladia capillacea, 60 min for Laurencia papillosa. The suitability of the Freundlich and Langmiur adsorption models were also investigated for each chromium-sorbent system. The results showed that Sargassum vulgare was found suitable for removing chromium from aqueous solution. The maximum sorption capacities of Halimeda tuna, Sargassum vulgare, Pterocladia capillacea, Hypnea musciformis, Laurencia papillosa were determined as 2.3, 33.0, 6.6, 4.7 and 5.3 mgg(-1).
    Journal of Environmental Biology 07/2005; 26(2 Suppl):329-33. · 0.68 Impact Factor
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    İsmail Karaboz, Atakan Sukatar, Aslı Parlakay
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    ABSTRACT: Green fluorescent protein (GFP) isolated from marine organisms and its usages. Many marine organisms are luminescent. The proteins that produce the light are primary light producers (aequorin or luciferase) and secondary proteins that shifts the red light for better penetration into the ocean. Green fluorescent protein (GFP) which is a secondary protein has extraordinary characteristics because of the fact that it is fluoroscent, has fluorophore made up of modified amino acid residues and has 3D structure. GFP isolated from the jellyfish Aequorea victoria and the sea pansy Renilla reniformis functions as energy-transfer acceptors in these organisms. In this study, the molecular structure of GFP that is isolated from marine organisms was explained and its recently usage was discussed. Özet: Çoğu denizsel organizma lüminesens özelliklere sahiptir. Işık oluşturan proteinler, primer ışık üreticiler (aequorin ya da lusiferaz) ve denizde daha iyi nüfuz etmesi için kırmızı ışığı değiştiren sekonder fotoproteinlerdir. Bir sekonder protein olan Yeşil floresans protein (GFP) floresans özellikte olması, modifiye olmuş amino asit kalıntılarından oluşan floroforu bulunması ve üç boyutlu yapısı nedeniyle sıra dışı özelliklere sahiptir. Deniz anası Aequorea victoria ve deniz menekşesi Renilla reniformis türlerinden izole edilen GFP, bu canlılarda enerji transferinde rol oynamaktadır. Bu çalışmada, denizsel organizmalardan elde edilen GFP'nin moleküler yapısı açıklanmış ve günümüzdeki kullanım alanlarına değinilmiştir. Anahtar Kelimeler: Aequorea victoria, Renilla reniformis, yeşil floresans protein.
    Journal of Fisheries & Aquatic Sciences Cilt Sayı/Issue. 01/2004; 21:3-4.
  • Atakan Sukatar
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    ABSTRACT: Studies on the Algal Productivity in South Aegean Region of Turkey: In this study, Ulva lactuca Linnaeus, Cystoseira compressa (Esper) Gerloff et Nizamuddin, C. crinita Duby, C. elegans Sauvageau, C. schiffneri G.Hamel, Hypnea musciformis (Wulfen) J.V.Lamaouroux, Laurencia papillosa (C.Agardh) Greville and Halopithys incurva (Hudson) Batters were collected from 11 stations of South Aegean Sea. The dry and fresh weights of these algae were compared. In addition, collection periods of these commercial species were suggested.

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