Polymers with their myriad functions are indispensable to any modern technology. Today, their production is largely based on fossil fuels. In view of their limited range, other sources are desirable on the long term. Beyond such considerations, renewable resources are also attractive as they can contain unique chemical structures. Thus, carbohydrates, fatty acids or terpenes contain a wealth of...

Maize (Zea mays) emits volatile terpenes in response to insect feeding and egg deposition to defend itself against harmful pests. However, maize cultivars differ strongly in their ability to produce the defense signal. To further understand the agroecological role and underlying genetic mechanisms for variation in terpene emission among maize cultivars, we studied the production of an important...

The essential oils of the leaves and fine stems of Pilocarpus microphyllus, collected on iron mineralized soil of the Serra de Caraj s, Southeast of Par State, Brazil, during the rainy and dry seasons, were obtained by hydrodistillation and analyzed by GC-MS. The main identified compounds were 2-tridecanone, beta-caryophyllene, 2-pentadecanone, caryophyllene oxide and germacrene D. Their perce...

The aim of this study was to perform chemical characterization of Lippia alba accessions from the Active Germplasm Bank of the Federal University of Sergipe. A randomized block experimental design with two replications was applied. The analysis of the chemical composition of the essential oils was conducted using a gas chromatograph coupled to a mass spectrometer. The chemical composition of th...

صلاخلا ــ ة : مت ةقرولا هذه يف ءاشنإ يف هدعاسملل مدقتم ماظن بناوج ذيفنتو ميمصت ضرع قتو و مي ءادأ حيحصت تارفش لأا ءاطخ ةليلق لا ةناتم ، ةينبم ىلع ءوفاكتلا رايتخا . موقي امه نيتيسيئر نيتفيظوب ةساردلا هذه يف مدقتملا ماظنلا : 1 ادأ باسحل ةيزاوتملا هاآاحملا ء تارفش حيحصت لأا ءاطخ ةليلق نمزب ةفاثكلا ادج ريصق ةنراقم ةمظنأب ةاآاحملا ةدوجوملا . 2 ةليلق ءاطخلأا حيحصت تارفشو فعضلا قطانم صحف نع ة...

The fresh leaves and brine of leaves of Thymbra spicata var. spicata (KARAKIZ) were analyzed by hydrodistillation, headspace and GC/MS techniques. The main components were determined as carvacrol, p-cymene, beta-myrcene, gamma-terpinene, a-terpinene and trans-caryophyllene. The essential oil and the main compounds, carvacrol and trans-caryophyllene, have been tested against E. coli, S. epidermi...

Composition of the essential oil obtained from dried flowering aerial parts of Teucrium scordium L. (Labiatae) was analyzed by GC and GC/MS. Fifty-six components were identified in the essential oil of T. scordium. The major constituents of the oil were beta-caryophyllene (22.8%), (E)-beta-farnesene (10.4%), caryophyllene oxide (8.6%), 1,8-cineole (6.1%) and beta-eudesmol (5.1%).

صخلملا Seasonal variation of zooplankton biomass has been carried out at two selected sites on Greater Zab River. Monthly samples of water were collected during period from January to December 2008. Some physico-chemical properties of water were studied including water temperature (from 8 to 30.5 C), hydrogen ion concentration (from 6.3 to 8), EC (from 255 to 821 μs.cm), turbidity (1085 NTU), d...