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Objective: The purpose of this study was therefore to investigate various physicochemical properties, phenolic composition and antioxidant capacities of the oak honey, large quantities of which are produced in the Thrace region of Northwest Turkey. Methods: Hunter color values (Lab), optical rotation, electrical conductivity, moisture and ash were measured as physicochemical determinants. Sugar, proline content, mineral, phenolic acids, total phenolic flavonoids contents were evaluated as chemical parameters. Ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging were used as antioxidant determinants. Results: The results determined that dark-colored honeys (mean 24.95±8.35 L) have proline levels (649.82±203.90 mg/kg), total phenolic content (TPC) (67.29±13.10 mgGAE/100 g) and total flavonoid content (TFC) (10.14±4.78 mgQE/100 g), a high ratio of fructose/glucose (1.65±0.18). Rutin (11.14±8.50 μg/g), p-coumaric acid (6.97±5.80 μg/g) and protocatechuic acid (6.12±4.39 μg/g) were the major phenolic components, and quercetin was also detected in varying amounts in all samples. Potassium (2523±0.28 mg/kg), calcium (63.40±3.20 mg/kg) and magnesium (38.88±0.65 mg/kg) were the major minerals in the honeys. Conclusion: Our results showed that physicochemical properties, phenolic compounds, antioxidant capacity, sugar and mineral contents successfully distinguish the geographical origins of oak honey. These findings will contribute to a more accurate evaluation of oak honey in the literature. [ABSTRACT FROM AUTHOR]

The honeydew of Marchalina hellenica is collected by honeybees for pine honey production, which is of great economic importance in Turkey. During 2009-2011 we investigated the predators of M. hellenica, which is distributed mainly in the areas with a Mediterranean climate - in the Aegean, Marmara and Mediterranean regions of Turkey. The findings showed that M. hellenica has many predators in the studied areas and that these play an important role in the forest ecosystem. These predators are: Anystis baccarum (L.) (Acarina: Anystidae); Allothrombium triticium Zhang and Allothrombium pulvinum Ewing (Acarina: Trombidiidae); Neoleucopis kartliana (Tanasijtshuk) (Diptera: Chamaemyiidae); Myrrha octodecimguttata (L.), Rodolia cardinalis Mulstant, Scymnus subvillosus (Goeze) (Coleoptera: Coccinellidae), Dichochrysa genei (Rambur), Dichochrysa prasina (Burmeister) and Chrysoperla lucasina (Lacroix) (Neuroptera: Chrysopidae); Wesmaelius subnebulosus (Stephens) (Neuroptera: Hemerobiidae), Cardiastethus nazarenus Reuter and Elatophilus pachycnemis Horváth (Hemiptera: Anthocoridae). The most efficient and common predator was N. kartliana, here recorded for the first time from Turkey. [ABSTRACT FROM AUTHOR]

Marchalina hellenica is the main honeydew producing insect of pine trees. It is endemic to Greece and Turkey and introduced to the Italian island of Ischia. It has one generation per year and the adult females appear on the trees only after mid March. Studies on the genetic structure of the insect show that the low genetic variability may be due to the fact that it can not be dispersed long distances in correlation with the parthenogenetic reproduction. The amount of honeydew produced by the insect varies over the year and mainly depends on the size and age of the nymphs. [ABSTRACT FROM AUTHOR]