Towards ex situ conservation of globally rare Turkish endemic Tripleurospermum fissurale (Asteraceae)

In Vitro Cellular & Developmental Biology - Plant - A rapid and efficient in vitro micropropagation system was developed to conserve Tripleurospermum fissurale (Sosn.) E.Hossain (Asteraceae), a...     

Evaluation of a new biosensor-based mushroom (Agaricus bisporus) tissue homogenate: investigation of certain phenolic compounds and some inhibitor effects

A biosensor based on mushroom tissue homogenate for detecting some phenolic compounds (PCs) and usage of the biosensor for quantifying certain substances that inhibit the polyphenol oxidase activity in mushroom (Agaricus bisporus) tissue homogenate is described. The mushroom tissue homogenate was immobilized to the top of a Clark-type oxygen electrode with gelatin and glutaraldehyde. Optimization of the experimental parameters was done by buffer system, pH, buffer concentration, and temperature. Besides, the detection range of eight phenolic compounds were obtained with the help of the calibration graphs. Thermal stability, storage stability, and repeatability of the biosensor were also investigated. A linear response was observed from 20 x 10(-3) to 200 x 10(-3) mM phenol. The biosensor retained approximately 74% of its original activity after 25 days of storage at 4 degrees C. In repeatability studies, variation coefficient (C.V.) and standard deviation (S.D.) were calculated as 2.44% and +/-0.002, respectively. Inhibition studies revealed that the proposed biosensor was applicable for monitoring benzoic acid and thiourea in soft drinks and fruit juices.     

Identification of promoters bound by c-Jun/ATF2 during rapid large-scale gene activation following genotoxic stress

The NH2-terminal Jun kinases (JNKs) function in diverse roles through phosphorylation and activation of AP-1 components including ATF2 and c-Jun. However, the genes that mediate these processes are poorly understood. A model phenotype characterized by rapid activation of Jun kinase and enhanced DNA repair following cisplatin treatment was examined using chromatin immunoprecipitation with antibodies against ATF2 and c-Jun or their phosphorylated forms and hybridization to promoter arrays. Following genotoxic stress, we identified 269 genes whose promoters are bound upon phosphorylation of ATF2 and c-Jun. Binding did not occur following treatment with transplatin or the JNK inhibitor SP600125 or JNK-specific siRNA. Of 89 known DNA repair genes represented on the array, 23 are specifically activated by cisplatin treatment within 3-6 hr. Thus, the genotoxic stress response occurs at least partly via activation of ATF2 and c-Jun, leading to large-scale coordinate gene expression dominated by genes of DNA repair.     

Antimicrobial activity of some Satureja essential oils

The genus Satureja is represented by fifteen species of which five are endemic and Satureja pilosa and S. icarica have recently been found as new records for Turkey. Aerial parts of the Satureja pilosa, S. icarica, S. boissieri and S. coerulea collected from different localities in Turkey were subjected to hydrodistillation to yield essential oils which were subsequently analysed by GC and GC/MS. The main constituents of the oils were identified, and both antibacterial and antifungal bioassays were applied. Carvacrol (59.2%, 44.8%, 42.1%) was the main component in the oils of S. icarica, S. boissieri and S. pilosa, respectively. The oil of S. coerulea contained beta-caryophyllene (10.6%) and caryophyllene oxide (8.0%) as main constituents.     

Using biplots to interpret gene expression patterns in plants

Plant biologists in fields of ecology, evolution, genetics and breeding frequently use multivariate methods. This paper illustrates Principal Component Analysis (PCA) and Gabriel's biplot as applied to microarray expression data from plant pathology experiments.     

Levels of zinc and magnesium in senile and diabetic senile cataractous lenses

Zinc and magnesium in serum, hair, and lens were determined in diabetic and nondiabetic patients who have been operated because of senile cataract. Both trace elements were measured by atomic absorption spectrometry, after acidic digestion of the lens and hair samples. Although there was no difference in serum, lens, and hair levels of magnesium between the two groups, the lens levels of zinc in diabetic patients (0.56+/-0.05 micromol/g dry weight) were significantly higher as compared with nondiabetic group (0.42+/-0.03 micromol/g dry weight). There was no statistically significant difference in serum and hair levels of zinc between the groups. The increased concentration of zinc in the lens of diabetic patients suggests that zinc might play a role in developmental mechanism of the diabetic senile cataract.     

Thalictricoside, a new phenolic compound from Thalictrum orientale

From the underground parts of Thalictrum orientale Boiss., a new phenolic compound 1 was isolated in addition to one known cyanoglycoside, lithospermoside (2). For the structure elucidation of all compounds, 1D- and 2D-NMR techniques (DEPT, COSY, HMBC, HSQC) and MS (HR-MALDI) were used. The structure of the new compound was established as 2-(4'-hydroxyphenyl)-nitroethane-4'-O-[beta-xylopyranosyl-(1 --> 6)-beta-glucopyranoside] (1).