Synthesis and structure-activity relationship of diene modified analogs of<Emphasis Type="Italic"> Matsucoccus</Emphasis> sex pheromones

The biological activity of the Matsucoccus spp. sex pheromones and diene modified analogs has been tested in forests of Israel and Portugal in order to explore the structure-activity relationship of the pine bast scale pheromone/kairomone system. The response of the adult predatory bugs, Elatophilus hebraicus and E. crassicornis and of the brown lacewing, Hemerobius stigma is more selective than that of the conspecific Matsucoccus males. The removal of the terminal methyl group from the diene terminus of both pheromones 1 and 2 eliminates all kairomonal activity but retains moderate pheromonal activity. Addition of a methyl group to the diene terminus of pheromones 1 and 2 sustains full pheromonal and kairomonal activities of the Elatophilus spp. but eliminates entirely the kairomonal activity of H. stigma. Subtle designed alterations in the structure of the diene group, typical of all Matsucoccus pheromones, change the mode of the kairomonal activity markedly.     

Anatomical localization and stereoisomeric composition of <Emphasis Type="Italic">Tribolium castaneum</Emphasis> aggregation pheromones

We report that the abdominal epidermis and associated tissues are the predominant sources of male-produced pheromones in the red flour beetle, Tribolium castaneum and, for the first time, describe the stereoisomeric composition of the natural blend of isomers of the aggregation pheromone 4,8-dimethyldecanal (DMD) in this important pest species. Quantitative analyses via gas chromatography–mass spectrometry showed that the average amount of DMD released daily by single feeding males of T. castaneum was 878 ± 72 ng (SE). Analysis of different body parts identified the abdominal epidermis as the major source of aggregation pheromone; the thorax was a minor source, while no DMD was detectable in the head. No internal organs or obvious male-specific glands were associated with pheromone deposition. Complete separation of all four stereoisomers of DMD was achieved following oxidation to the corresponding acid, derivatization with (1R, 2R)- and (1S, 2S)-2-(anthracene-2,3-dicarboximido)cyclohexanol to diastereomeric esters, and their separation on reversed-phase high-performance liquid chromatography at −54°C. Analysis of the hexane eluate from Porapak-Q-collected volatiles from feeding males revealed the presence of all four isomers (4R,8R)/(4R,8S)/(4S,8R)/(4S,8S) at a ratio of approximately 4:4:1:1. A walking orientation bioassay in a wind tunnel with various blends of the four synthetic isomers further indicated that the attractive potency of the reconstituted natural blend of 4:4:1:1 was equivalent to that of the natural pheromone and greater than that of the 1:1 blend of (4R,8R)/(4R,8S) used in commercial lures.     

Synthesis of hydrogarnet from molten slag and its hydrogen chloride fixation performance at high temperature

Hydrogarnet was synthesized hydrothermally below 200°C using molten slag obtained from municipal solid waste. For comparison, it was also synthesized using pure-phase CaO–Al₂O₃–SiO₂–H₂O, as reported previously. The structural and textural properties of this material were investigated using various analytical and spectroscopic techniques such as X-ray diffraction, X-ray fluorescence spectrometry, atomic absorption spectrometry (AAS), thermogravimetry/differential thermal analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. The Cl⁻ fixation ability of hydrogarnet was investigated in the temperature range 500–800°C in a fixed-bed flow reactor using a HCl concentration (1000 p.p.m.v.) similar to that of incinerator exhaust gas. Under these experimental conditions, the hydrogarnet was capable of reducing the HCl gas level to less than 1 p.p.m.v. Analysis of the spent catalyst revealed that the hydrogarnet was being transformed into wadalite and CaCl₂ at high temperatures. The elution test for chromium ions in hydrogarnet obtained from slag was also used, and it was found that chromium ions were not eluted from hydrogarnet. Received: January 27, 2001 / Accepted: October 11, 2001     

Removal of Cr(VI) from contaminated soil by electrokinetic remediation

A new process for the removal of hexavalent chromium [Cr(VI)] contaminated soil is described. The process provides for an efficient removal of anionic chemicals from contaminated soils. Chromate anions were removed from the soil to the anodic reservoir by the moving force of electromigration. In this process, the chromate anions that accumulate in the anodic reservoir are simultaneously eliminated by using a column packed adsorbent. The adsorbent (immobilized tannin) used was chemically incorporated into cellulose. Cr(VI) was found to be adsorbed to this adsorbent efficiently. In the electrokinetic process, the pH of the aqueous solution in the anodic reservoir was decreased by the electrolysis of water. In the present study, the pH of the solution in the anodic reservoir is maintained at pH 6 by the addition of an aqueous alkaline solution during the electrokinetic process. The advantage of pH control is that it promotes the release of Cr(VI) from the soil by electromigration, thus permitting the maximum adsorption of Cr(VI) on the immobilized tannin. Simultaneous collection of Cr(VI) from the anodic reservoir leads to the protection from secondary contamination with Cr(VI).     

Vitellogenin induction in Cyprinus carpio treated with 17beta-estradiol and 4-nonylphenol

The aim of the present study was to demonstrate induction ofvitellogenin in the common carp (Cyprinus carpio) as abiomarker for monitoring freshwater ecosystems. Sexually undifferentiated specimens of common carp were treated experimentally with 17-estradiol and increasing doses of 4-nonylphenol and levels of plasma Vtg were measured in orderto: 1) validate an ELISA assay for plasma Vtg in the common carpusing the polyclonal rabbit anti-salmon Vtg antibody AA1 (Biosense, Norway); 2) check the sensitivity of carp juvenilesin producing Vtg in response to estrogen stimulation. The grouptreated with 17-estradiol showed high induction (156%)with respect to controls, also groups treated with 4-nonylphenolshowed induction of Vtg. The group treated with 100 mg kg^-1b.wt showed an induction of 61%. A statistically significantcorrelation was found between dose and response. This preliminary study demonstrate a response to the ELISA assay for Vtg in the common carp using rabbit anti-salmon antibody AA1. With further evidence the tested biomarker might be proposed for large scale monitoring of estrogenic effects caused by pollution in urban and industrial effluents.