No abstract

Thymus is represented by 39 species (60 taxa) in Turkey and the rate of its endemism is 45% in Turkey. The herb is widely used for several purposes. Its essential oil compositions and biologically active substances are affected by the phenological stages. Therefore, the aim of this study is to evaluate the variations in the essential oil composition of Thymus × citriodorus (Pers.) Schreb. growing in Southeastern Anatolia Region of Turkey at different phenological stages (pre-flowering, full flowering, post flowering). The oils were obtained by hydrodistillation of air-dried samples. The yields of oils (w/w %) at different phenological stages was respectively 2.0% at pre-flowering state, 1.9% at flowering stage, and 1.3% at post-flowering stage. T. × citriodorus was determined mainly by using GC/MS. A total of 21 compounds, representing 93.9% in the preflowering stage, 98.8% in the flowering stage and 98.91% in post-flowering of the total oil, were identified. Monoterpene hydrocarbons (terpinolene) and oxygenated monoterpenes (α-terpineol) were observed to have the highest percentage in T. × citriodorus oil. The major compounds of the oil were terpinolene, α-terpineol, linalool, bornyl acetate and borneol. The highest percentage of terpinolene was determined to be 71% in flowering stages.

In Turkey, almonds are grown via the following three methods: organic (O), conventional (C) and good agricultural practice (GAP). Almond seeds are mostly consumed as nuts; thus, the researchers have focused different analyses on only seeds. However, in Turkey, unripe green almond hulls are also consumed. Therefore, we studied the contents of some bioactive components, pigments, and malondialdehyde (MDA) and the antimicrobial, antioxidant, and antimutagenic activities of O, C, and GAP 'Ferradual' (Frd) and 'Ferragnes' (Frg) almond hull extracts. The highest total ascorbic acid content was found in O Frd (2.1 mg/g fresh weight [FW]) and GAP Frg (2.0 mg/g FW). The total phenolic content and total flavonoid content in all the genotypes ranged from 19.2 and 43.9 mg/g FW and 3.2 and 20.2 mg/g FW, respectively. In general, the antioxidant activity of C Frg and C Frd was low. C Frg had the highest MDA content (8.53 µmol MDA/g FW), whereas O Frg had the lowest MDA content (0.89 µmol MDA/g FW). The samples had varying ratios of chlorophyll a and b. The O samples had more total carotenoid content than the C samples. The antibacterial activity was only observed in the O and GAP Frd extracts. The antifungal activity could not be detected in any of the extracts of samples. Varying antimutagenic activity in Salmonella typhimurium TA 98 strain and content of some phenolics were observed depending on the variety, growing conditions, and dose.

Indigo blue is a natural dye used for thousands of years by civilizations to dye fabric blue and it is naturally obtained from Isatis tinctoria. I. tinctoria is not only used for extraction of indigo blue color but also used medicinally in Traditional Chinese Medicine because of its active compounds. Sodium dithionite (Na 2 S 2 O 4 ) is used in dye bath for indigo blue extraction, but this reducing agent and its derivatives are major pollutants of textile industry and subsequently have hazardous influences on public health. Herein, the present study was designed to obtain the high yield of natural indigo dye but with low possible toxic effect. In this context, genotoxic effects of particular combinations of natural dye solutions obtained from Isatis tinctoria subsp. tomentolla with Na 2 S 2 O 4 as reducing agent were investigated. Dye solutions were obtained using two different pH levels (pH 9 and 11) and three different concentrations of Na 2 S 2 O 4 (2.5, 5 and 10 mg/ml). In addition to the dye solutions and reducing agent, aqueous extracts of I. tinctoria were assessed for their genotoxicity on human lymphocytes. For in vitro testing of genotoxicity, chromosomal aberrations (CAs), sister chromatid exchanges (SCEs) and mitotic indexes (MI) assays were used. Accordingly, Na 2 S 2 O 4 caused significant increases in CA and SCE as well decrease in MI but the genotoxic effects of sodium dithionite were reduced with natural indigo dye. As a result, aqueous extracts of Isatis leaves removed the toxic effects of sodium dithionite and showed anti-genotoxic effect. For the optimal and desired quality but with less toxic effects of natural dye, 2.5 mg/ml (for wool yarn) and 5 mg/ml (for cotton yarn) of Na 2 S 2 O 4 doses were found to be the best doses for reduction in the dye bath at Ph 9.

Indigo dye has a distinctive blue color and is one of the oldest known dyestuffs. In order to identify new Isatis genotypes for indigo production, 14 Isatis taxa collected from native area were grown under field conditions in Kahramanmaraş, Turkey. The effects of taxa and harvest times on leaf, indigo and indican yield were analyzed and compared with culture species (Isatis tinctoria and Isatis indigotica) by using spectrophotometer and HPLC. High indigo yield (87.13 kg/ha) was obtained from Isatis constricta and I. tinctoria subsp. tomentolla (Mersin location) had high indican yield (12.25 mg/g) in fresh leaves. The present work identified high indigo yielding taxa that may be used for genetic improvement in order to re-introduce Isatis species in the agricultural systems of Mediterranean regions. Especially I. constricta can be evaluated in terms of higher indigo yield than the native and culture taxa. I. constricta is an endemic plant in endangered category. This situation reveals that the need for the conservation of the species. To the best of our knowledge, there is no previous study reported about indigo contents of the studied 11 Isatis spp. so far.