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Carvacrol is a major component of many essential oils of the genus Thymus, Satureja, and Origanum, determining their antimicrobial, antioxidant, and other properties. The aim of the present study was to investigate some physicochemical and biological properties of pure carvacrol. The surface tension and density were measured at six different temperatures (30, 40, 50, 60, 70, and 80°C). The surface tension values were between 53.11 and 60.38 mN/m, while density varied from 0.978 to 0.99 kg/m3. The antibacterial activity against seven pathogenic and conditionally pathogenic bacteria was investigated. The diameter of the inhibition zones was determined in the range of 3.9–4.9 mm. The antioxidant activity was determined by the oxygen radical absorbance capacity (1687.0 µmol TE/mL) method.

Morus nigra, black mulberry, is the most attractive among mulberry species. The study aimed to determine human health-promoting content and antifungal activity in fruits of seven black mulberry genotypes grown in the Tortum district of Turkey. The genotypes exhibited significant differences in most of the human health-promoting content. Among individual sugars and organic acids, glucose (6.98–8.03 g/100 g fresh weight base) and malic acid (6.33–10.45 g/100 g fresh weight base) were predominant. The ascorbic acid content of genotypes was found between 18.13 and 26.77 mg/100 g fresh weight base, indicating that black mulberry fruits had moderate ascorbic acid content. Total phenolic content, total antioxidant capacity, and total anthocyanin contents in fruit extracts of seven black mulberry genotypes were also investigated. The results showed that the levels of the aforementioned parameters changed depending on genotypes. The total phenolic and total anthocyanin contents were in the range of 1,656–2,348 μg gallic acid equivalent (GAE)/g and 623–804 μg C3GE (cyanidin-3-glucoside equivalent)/g, respectively. The genotypes had antioxidant capacity between 17.41 and 3.86 μg/mL and between 10.08 and 14.11 μmol TE/g measured by the 2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power assay, respectively. Some of the genotypes (TOR-1 and TOR-2) had high antifungal activity particularly against C. albicans. It was determined that the people living in the region traditionally use mulberries as blood enhancer, immune system booster, and mouth lesion treatments to protect themselves against different types of cancers and against inflammation. The present results confirm that attractive fruits of black mulberry are a rich natural source of phenolic antioxidants and can contribute to the dietary intake of antioxidants, depending on genotypes.

The motherland of the olive is considered as east of the Mediterranean Basin. Turkey is partly located within this basin having a rich source of biodiversity. Olive growing in Turkey is carried out in the Aegean, Marmara, Mediterranean, Southeastern Anatolia and Black Sea Regions. Climatic factors determine the cultivation limits of olive which is not very selective in terms of soil demand. In regions where olives are grown, the Mediterranean climate prevails. Winters are warm and rainy in the region, while summers are hot and dry. On the other hand, severe cold damage in some years can cause significant damage especially in the inner parts of Aegean, Marmara and Black Sea Regions. As a matter of fact, it is known that 31.8% of olive plantations in Turkey are exposed to occasional frost damage. This situation has revealed the necessity of determining the varieties with high frost tolerance and determining the suitable varieties for the regions where cold damage may occur. In the study, 40 registered olive cultivars in "Kemalpaşa Olive Germplasm Bank" in Bornova Olive Research Institute, in İzmir were screened in terms of frost tolerance. To evaluate the frost tolerance (LT50) of cultivars, as estimated by ion leakage (electrical conductivity), leaf samples taken in six different periods over two years were exposed to temperatures at +4 °C (control), -2 °C, -5°C, -8 °C, -11°C, -14 °C, -17 °C and -20 °C. In conclusion; it has been determined that frost tolerance of olive varieties revealed significant variability both genetically and seasonally. Butko, Memeli, Otur, Gemlik, Sinop No 5, Yün Çelebi, Kara Yaprak, Satı and Sarı Ulak were determined as cultivars that were more tolerant of frost. Sinop No 1, Marantelli, Ayvalık, Görvele, Çakır, Samsun Tuzlamalık, Erkence, Saurani, Eşek Zeytini (Tekirdağ), Kan Çelebi, İzmir Sofralık, Çilli, Samsun Yağlık, Domat, Eşek Zeytini (Ödemiş), Saçaklı Otur, Sinop No 4, Memecik, Nizip Yağlık, Tekirdağ Çizmelik and Patos were found to be moderately tolerant cultivars while Edincik, Sinop No 6, Çekişte, Mavi, Kiraz, Kilis Yağlık, Çelebi (İznik), Trabzon Yağlık, Uslu and Girit olive cultivars were grouped as cultivars having low tolerance to frost. In addition, data showed that cold acclimation in the olive is quite important, and exposure to low temperatures for a certain period of time has significantly increased the frost tolerance. However, this condition was not stable and could rapidly become reversed when temperature reached to the point at which adapdation did not ensure. [ABSTRACT FROM AUTHOR]

Annual patterns of cold hardiness, total soluble sugars (TSS) and proteins (TSP) were characterised during two consecutive years (May 2003-April 2005) in leaf and bark tissues of olive (Olea europaea L.) `Gemlik' trees. One- year-old shoots from 13-year-old olive trees were collected each month and exposed to low temperature at 4°C, -5°C, -10°C, or -20°C for 12 h to determine their cold-hardiness (LT50 assessed by electrolyte leakage). A considerable increase in cold-hardiness was observed with decreasing temperature. Leaf and bark tissues exhibited an increase in cold-hardiness during the Autumn, which reached a maximum in mid-Winter, then gradually decreased during the Spring, and reached a minimum in mid-Summer. Results indicated that leaf and bark tissues in both experimental years responded similarly to cold, with a continuous increase in their TSS and TSP contents during field adaptation in Autumn and Winter, which paralleled their cold-hardiness. The annual cycle of TSP from leaf and bark tissue was characterised by one dimensional SDS-PAGE. A seasonal fluctuation was observed in leaf proteins of 66 kDa and 43 kDa, and in bark proteins of 70 kDa, 43 kDa and 16 kDa, which paralleled cold- acclimation. Evaluation of these leaf and bark TSP profiles showed that these polypeptides disappeared in the Summer, followed by their accumulation again during the Autumn and Winter. Moreover, all these polypeptides became less visible during the Spring. The relationships between these five proteins, TSS contents, and cold-hardiness in olive are discussed. [ABSTRACT FROM AUTHOR]

The effects of heat injury induced by long exposures were evaluated in strawberry (Fragaria × ananassa 'Camarosa') plants in this study. Seedlings were grown in 14 × 12 cm pots using perlite for three weeks at 25/10°C day/night temperature, and watered daily by modified 1/3 Hoagland nutrient solution. Half of the plants were transferred to a growth chamber with a constant 25°C, 16/8 h (light/dark) photoperiod regime and 1200 lux light intensity for a week to acclimate the plants. Temperature was increased stepwise (5 K per 48 h) to 30, 35, 40°C and finally to 45°C. In addition to others, plants were transferred from the outside to the growth chamber, at each temperature step to impose a heat shock. Leaf relative water content (RWC, %), loss of turgidity, chlorophyll content (Spad value) and heat-stress tolerance (HTS; LT[sub 50]) were measured in control and stressed plants. Total soluble proteins and total DNA were extracted from the leaves following the above treatments using standard procedures and total protein contents were determined using a Bradford assay. In general, effects of gradual heat stress (GHS) and shock heat stress (SHS) on the variables studied were mostly significant, except for chlorophyll content, while the effect of temperatures was significant for all the variables. Interaction between the heat stress type and temperature treatments was not significant for leaf RWC, loss of turgidity and chlorophyll content. Data also indicated that total protein and DNA contents were changed significantly by heat stress types (GHS and SHS) and/or temperature treatments. The plants exposed to GHS exhibited a significant increase in HST compared with the plants exposed to SHS (LTs0 of 41.5°C and 39°C, respectively). Consequently, gradual heat stress increased HST in strawberry leaves. Increased HST may be associated with the accumulation of several heat-stable proteins in GHS plants. [ABSTRACT FROM AUTHOR]