Tugba Bayrak Ozbucak

Essential oil composition and antiradical activity of the oil of Iraq plants

This study examined the antiradical activity and chemical composition of essential oils of some plants grown in Mosul, Iraq. The essential oils of myrtle and parsley seed contained α-pinene (36.08% and 22.89%, respectively) as main constituents. Trans-Anethole was the major compound found in fennel and aniseed oils (66.98% and 93.51%, respectively). The dominant constituent of celery seed oil was limonene (76.63%). Diallyl disulphide was identified as the major component in garlic oil (36.51%). Antiradical activity was higher in garlic oil (76.63%) and lower in myrtle oil (39.23%). The results may suggest that some essential oils from Iraq possess compounds with antiradical activity, and these oils can be used as natural antioxidants in food applications.

Foliar resorption in Quercus petraea subsp. iberica and Arbutus andrachne along an elevational gradient

Abstract• The resorption of nutrients (mainly N and P) from senescing leaves may be a key component of adaptive mechanisms that conserve scarce nutrients. Resorption may be expressed in two ways as resorption efficiency (RE) which is the ratio of the resorbed amounts of nutrient losses during leaf senescence in relation to its prior amount deposited in leaves and resorption proficiency (RP) is the level to which nutrient concentration per unit leaf mass is reduced in senescent leaves.• There is still much debate whether or not different life-forms (i.e. deciduous and evergreen species) show different foliar resorption patterns. Two sympatric species, namely Quercus petraea (Mattuschka) Liebl. subsp. iberica (Steven ex Bieb.) Krassiln. (deciduous) and Arbutus andrachne L. (evergreen) along an elevational gradient were compared with each other to determine whether or not nitrogen and phosphorus resorption efficiency and proficiency varies along the elevational gradient and which leaf parameters were as related to RE and RP.• NRE was found to be rather low in Q. petraea subsp. iberica compared to other deciduous species. Similarly, PRE in A. andrachne was rather low compared to other evergreen species. Mean residence time (MRT) measures how long a unit of nitrogen (MRTN) and phosphorus (MRTP) is present in the plant. MRTN and MRTP were found to be considerably higher in A. andrachne compared to Q. petraea subsp. iberica. In both species, the foliar N/P ratio was below 14 along the elevational gradient and, according to this threshold value, N-limitation occurred in the study area. Although both species in the present study show incomplete resorption deciduous species was more proficient as compared to evergreen one due to low N and P concentrations in senescent leaves. Based on the significant correlations (p < 0.05 and 0.01) between MRT and foliar resorption, it can be concluded that MRT could interfere with the mechanisms controlling nutrient resorption.Résumé• La résorption des éléments nutritifs (essentiellement N et P) par sénescence des feuilles peut être une composante clé des mécanismes d’adaptation qui permettent de conserver les rares éléments nutritifs. La résorption peut être exprimée de deux façons : l’efficience de résorption (RE) qui est le rapport entre la quantité résorbée des pertes d’éléments nutritifs au cours de la sénescence des feuilles par rapport à son montant déposé auparavant dans les feuilles et la capacité de résorption (RP) qui est le niveau auquel la concentration des éléments nutritifs par unité de masse de feuilles est réduite dans les feuilles sénescentes.• Il reste encore beaucoup de débat pour déterminer si les différentes formes de vie (c’est-à-dire les espèces décidues et les espèces sempervirentes) présentent différents modes de résorption foliaire. Deux espèces sympatriques, à savoir Quercus petraea (Mattuschka) Liebl. subsp. iberica (Steven ex Bieb.) Krassiln. (décidue) et Arbutus andrachne L. (sempervirente), ont été comparées l’une à l’autre, le long d’un gradient altitudinal, afin de déterminer si l’efficience de résorption de l’azote et du phosphore et la capacité de résorption varient le long d’un gradient altitudinal et quels paramètres de la feuille sont liés à RE et RP.• NRE a été trouvé plutôt faible chez Q. petraea subsp. iberica par rapport à d’autres espèces décidues. De même, chez A. andrachne PRE a été plutôt faible par rapport à d’autres espèces sempervirentes. Le temps de résidence moyen (MRT) mesure combien de temps une unité d’azote (MRTP) et de phosphore (MRTP) est présente dans la plante. MRTP et MRTP étaient considérablement plus élevés chez A. andrachne par rapport à Q. petraea subsp. iberica. Chez les deux espèces, le ratio foliaire N/P était inférieur à 14 le long du gradient altitudinal, en fonction de la valeur de ce seuil, une limitation d’azote s’est produite dans la zone d’étude. Bien que les deux espèces, dans la présente étude, montrent une résorption incomplète, l’espèce décidue avait une meilleure capacité de résorption comparativement à l’espèce sempervirente en raison de la faible concentration de N et de P dans les feuilles sénescentes. Sur la base des corrélations significatives (p < 0.05 et 0.01) entre MRT et la résorption foliaire, il peut être conclu que MRT pourrait interférer avec les mécanismes de contrôle de la résorption des éléments nutritifs.

Individual and Combined Use of Rosemary and Origanum in Soybean Oil as Natural Antioxidants

Dried rosemary and origanum were added to soybean oil, individually and in combination, to determine their effect on the oxidation stability of soybean oil. Samples were stored at two different temperatures (60°C and room temperature) and oxidation was determined by peroxide value and conjugated diene value. The treated soybean oil samples showed evidence of antioxidant activity at 60°C and at room temperature. Furthermore, it was observed that the herbs stored under room temperature had a higher activity compared to those stored at 60°C.

The Effects of Elevation on the Morpho-Anatomical and Ecological Traits in Cyclamen coum subsp. coum Mill. Populations in the Central Black Sea Region of Turkey in Contrasting Habitats

ABSTRACT The differences in morpho-anatomical, ecological and biochemical traits of Cyclamen coum subsp. coum, threatened plant listed in CITES (Convention on International Trade in Endangered Species of Wild Fauna & Flora) have been investigated in the central Black Sea region of Turkey in the context of its distribution at different altitudes. We found that shoot length, bulb width, leaf width and length, number of branches and flowers were significantly different along elevation gradient, whereas length of tubers, number of living and dead leaves, number of nodes, specific leaf area (SLA) and leaf mass area (LMA) values, did not differ significantly, PCA analysis revealed that leaf length and width, the number of branches, soil organic matter content and available potassium concentration and N concentrations of above and belowground parts and reproductive effort (RE3) played significant role in differentiation of the studied populations, while several other studied factor were found not significant. The reproductive effort of individuals from the sea level was higher. We suggest that significant differences in the studied traits may indicate the ecotypic differentiation among populations.