Browsing by Author "Vurdu H."

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Botany of Crocus ancyrensis through domestication
(2010-01-31) Kravkaz I.S.; Vurdu H.
Crocus ancyrensis (Herbert) Maw is an endemic species and widely distributed in the Central Anatolia and the Western Black Sea region of Turkey. The species is under threat of heavy grazing, uncontrolled gathering, recreational pressure and many different kinds of land disturbances. The aim of this study is to examine the phenology, morphology and seed formation of this species in its natural habitat in Kastamonu area. The observation and the measurements have been made at three locations. C. ancyrensis is a yellow colored spring flowering species. Leaf initiation starts in just a couple of days before or with flowering. Flowering time is between the second half of February and the first half of March. The lifespan of the flower is about 15 days depending on climate. The capsule can be seen in mid April above the soil and seed maturation is at the end of May which is about 45 days after flower disappearance. The leaves dry and disappear in July. On the average, each capsule has 30 seeds and the one thousand seed weight is 3,52 g. The seed requires 10°C±2°C and 70% relative humidity for germination. As a result, there is a possibility to domesticate this species from its seeds in order to conserve or to make mass agricultural production for its further uses.
Coating performances of crimean juniper (juniperus excelsa M. Bieb.) wood
(2019-01-01) Öncel M.; Vurdu H.; Kaymakçi A.; Özkan O.E.; Aydogan H.
The purpose of this study is to determine the varnish layer hardness and varnish adhesion strength of the varnished Crimean juniper (Juniperus excelsa M. Bieb.) wood growing naturally in the Kastamonu region of Turkey. Test samples were varnished with UV-resistant polyurethane alkyd resin high gloss varnish (PAV) and water-based acrylic resin gloss varnish (WBAV). The varnish adhesion strength test was carried out by using universal testing machine. The varnish layer hardness was measured by using König pendulum hardness tester. Additionally, the colour properties were measured by spectrophotometer equipment that used the L*a*b* colour space. The adhesion strength of the polyurethane varnish and the water-based varnish were determined 2.81 MPa and 2.25 MPa respectively. Surface hardness value for water-based varnish and polyurethane varnish were determined 71 and 25 oscillation respectively. Detecting the performance of polyurethane and water-based varnish applications for the Crimean juniper wood will provide guidance in which type of varnish will be better for finishing. As a result, in varnish applications of the wood, it is recommended that water-based acrylic varnish should be applied when surface hardness is required. In addition, polyurethane alkyd varnish should be applied when better surface adhesion strength is desired.
DNA protection, antioxidant, antibacterial and enzyme inhibition activities of heartwood and sapwood extracts from juniper and olive woods
(2015-08-21) Özkan O.E.; Zengin G.; Akça M.; Baloʇlu M.C.; Olgun Ç.; Altuner E.M.; Ateş S.; Aktümsek A.; Vurdu H.
In this study, DNA protective, antioxidant, antibacterial and enzyme inhibiting properties of methanol extracts obtained from juniper and olive heartwood and sapwood were determined. These extracts were tested by five antioxidant methods (DPPH scavenging, FRAP, CUPRAC, metal chelating and phosphomolybdenum). Generally, heartwood extracts of both species are more efficient for DPPH radical scavenging activity, cupric ion reducing activity, ferric reducing antioxidant power and metal chelating activity than sapwood extracts. When compared to heartwood extracts, sapwood extracts have larger inhibition zone in disk diffusion test. In addition, all extracts showed high antibacterial activity against Staphylococcus aureus. DNA protection of both extracts had a capacity to inhibit the DNA damage arisen from Fenton's reagent. The highest DNA protective activity was observed in juniper sapwood extract with 84%. Furthermore, other extracts also indicated more than 60% of DNA protective activity. Olive wood extracts displayed the strongest enzyme inhibition activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Although juniper heartwood extracts showed highest anti-amylase, anti-glucosidase and anti-tyrosinase effects, they had no ability for inhibition BChE. The methanol extracts of olive samples demonstrated the most antioxidant activity (DPPH, CUPRAC and FRAP). In addition, juniper samples showed the highest anti-amylase, anti-tyrosinase, metal chelating and DNA protective activity. According to these results, the extracts of juniper and olive wood can be considered as a source of natural bio active agents for dietary, pharmacological and medicinal applications. This research will also serve as a base for future studies about biological activities of wood extracts.
Effect of post-heat treatment on fire retardant treated wood properties
(2022-07-01) Özkan O.E.; Temiz A.; Tor Ö.; Vurdu H.
In this study, Anatolian black pine (Pinus nigra subsp. pallasiana) was treated with fire retardants of 10, 20, and 30% aqueous solutions composed of di-ammonium phosphate (DAP), borax, boric acid, and glucose to determine the effectiveness of these chemicals in preventing the spread of fire. The treated wood was subjected to post-heat treatment at 120, 150, and 180 °C for 1 h to examine the effects of the post-heat treatment on pH changes, anti-swelling efficiency, water absorption, mechanical strength, accelerated weathering, leaching resistance, thermogravimetric analysis (TGA), UL-94 vertical burning test and crystallinity index. The post-heat treatment of fire-retardant treated wood reduced water intake and increased dimensional stability, while also improving mechanical and thermal properties in general. DAP/glucose complexes promote phosphorus fixation in wood and reduce leaching, resulting in long-term fire protection of wood in service. Because of these improvements in the post-heat treated wood by impregnated fire retardant, it can potentially be used as a reliable engineering material in a wide range of structural applications.
The tensile shear strength of outdoor type plywood produced from fir, alnus, pine and poplar wood
(2019-01-01) Öncel M.; Vurdu H.; Aydoğan H.; Özkan O.; Kaymakci A.
In this study, it is aimed to determine both the tensile-shear strengths of plywood that produced by using phenol formaldehyde resin from Uludağ fir (Abies nordmanniana subsp. bornmülleriana Mattf.), alder (Alnus glutinosa L.), scots pine (Pinus sylvestris L.) and Samsun poplar (77/51 Populus deltoides Bartr.) trees rotary cut veneers combinations of poplar-pine, poplar-fir, poplar-alder and poplar wood along with the effect of wood types on adhesion quality of glue. According to standards TS 3969 EN 314-1, and TS EN 314-2 adhesion class 3, the test specimens were prepared and tested for the adhesion quality. The obtained data were analyzed statistically by using SPSS 22 statistical program. As a result, the tensile-shear strength values of poplar, pine-poplar, fir- poplar and alder-poplar plywood types were found to be as averages 1.34 N.mm-2, 1.66 N.mm-2, 2.18 N.mm-2 and 2.46 N.mm-2 respectively. Also, it was found that there was no significant difference between the alder poplar and fir-poplar plywood types about tensile-shear strength. Since these all plywood combinations are satisfied the required 1 N.mm-2 strength value according to TS EN 314-2, all plywood types in this study are of suitable quality for outdoor uses.
The World Saffron and Crocus collection: Strategies for establishment, management, characterisation and utilisation
(2011-01-01) Fernández J.A.; Santana O.; Guardiola J.L.; Molina R.V.; Heslop-Harrison P.; Borbely G.; Branca F.; Argento S.; Maloupa E.; Talou T.; Thiercelin J.M.; Gasimov K.; Vurdu H.; Roldán M.; Santaella M.; Sanchís E.; García-Luis A.; Suranyi G.; Molnár A.; Sramko G.; Gulyas G.; Balazs L.; Horvat O.; Rodríguez M.F.; Sánchez-Vioque R.; Escolano M.A.; Reina J.V.; Krigas N.; Pastor T.; Renau-Morata B.; Raynaud C.; Ibadli O.; Polissiou M.; Tsimidou M.Z.; Tsaftaris A.; Sharaf-Eldin M.; Medina J.; Constantinidis T.; Karamplianis T.; De-Los-Mozos-Pascual M.
Since 2007, the European Commission AGRI GEN RES 018 "CROCUSBANK" action has permitted the creation of the alleged World Saffron and Crocus Collection (WSCC), a unique collection which contains a representation of the genetic variability present in saffron crop and wild relatives at global scale. At present the germplasm collection, housed at the Bank of Plant Germplasm of Cuenca (BGV-CU, Spain), consists of 572 preserved accessions representing 47 different Crocus species (including saffron Crocus) and is expected to increase up to more than 600 accessions by the end of CROCUSBANK action (May 2011). The preserved biodiversity of saffron (Crocussativus L.) covers a wide range of the genetic variability of the crop and currently consists of 220 accessions from 15 countries: 169 of these come from European cultivation countries, 18 from commercial areas in non EU countries, 26 from regions of minimal or relict production and/or from abandoned fields and 7 from commercial nurseries. The non-saffron Crocus collection currently comprises 352 accessions: 179 collected from the wild in 12 countries of natural distribution, 24 from donations of public and private institutions, 91 from commercial nurseries and 58 acquired from BGV-CU collection management. Here we provide a record of collections, activities concerns and current strategies for documentation, conservation, characterisation, and management of the collection as important tools for researchers with interest in these valuable genetic resources. © 2010 The Author(s).