Do heavy metals and metalloids influence the detoxification of organic xenobiotics in plants?

Background, aim and scope  

Mixed pollution with trace elements and organic industrial compounds is characteristic for many spill areas and dumping sites. The danger for the environment and human health from such sites is large, and sustainable remediation strategies are urgently needed. Phytoremediation seems to be a cheap and environmentally sound option for the removal of unwanted compounds, and the hyperaccumulation of trace elements and toxic metals is seemingly independent from the metabolism of organic xenobiotics. However, stress reactions, ROS formation and depletion of antioxidants will also cause alterations in xenobiotic detoxification. Here, we investigate the capability of plants to detoxify chlorophenols via glutathione conjugation in a mixed pollution situation.     

Molecular/chemical ecology in sponges: evidence for an adaptive antibacterial response in<Emphasis Type="Italic"> Suberites domuncula</Emphasis>

Sponges (Porifera) represent the evolutionary oldest metazoan phylum still extant today. They have developed a complex Bauplan, based on the existence of structural and regulatory molecules; many of these have been cloned and analyzed in the past years. The demosponge Suberites domuncula has been used as a suitable model to demonstrate that these animals not only possess an adaptive immune response on the level of cytokines, but also, as pointed out here, on the level of synthesis of bioactive alkyl-lipid derivatives. From specimens of S. domuncula the two lyso-PAF (platelet-activating factor) compounds, 1-O-hexadecyl-sn-glycero-3-phosphocholine and 1-O-octadecyl-sn-glycero-3-phosphocholine, have been identified and characterized. These two lyso-PAFs showed pronounced anti-bacterial activity. In the central part of this paper it is shown that the level of synthesis of the lyso-PAF congeners increased in response to the model compound, the endotoxin lipopolysaccharide (LPS). Treatment of the tissue with LPS for 72 h substantially increased the synthesis. In order to prove that the lyso-PAFs are really synthesized by the sponge, the key enzyme of the alkyl-dihydroxyacetonephosphate pathway, i.e. alkyl-dihydroxyacetonephosphate synthase (ADS), was cloned from S. domuncula. This sponge enzyme comprises the characteristic features of metazoan ADS enzymes; it is increasingly expressed in the tissue and in the in vitro cell culture system after exposure to LPS. These data are taken as a strong indication that bioactive, low-molecular weight, non-proteinaceous lipid derivatives function in an adaptive manner in response to the endotoxin.Communicated by R. Cattaneo-Vietti, Genova     

Korrelation meteorologischer und pflanzenphänologischer Indikatoren des Klimawandels

Goal and Scope

While the rise of the air temperature as part of the global climatic change seems to be widely assured, questions about the effects of this phenomenon in ecological systems get more and more interesting. In this sense this article shows by the example of monitoring sites in Baden-Württemberg the correlation of air temperature measurements with data on the phenology of selected plants.

Methods

To this end the data on air remperature and plant phenology which are gathered from spatial dislocated measurement sites were correlated by prior application of Kriging interpolation. In addition, geostatistics are ssed to analyze and cartographically depict the spatial structure of the phenology in spring and in summer.

Results and Conclusion

The statistical analysis reveals a significant relationship between the rising air temperature and the early beginning phenological phases like blooming or fruit maturation. From 1991 to 1999 spring time as indicated by phenological phases begins up to 14 days earlier than from 1961 to 1990. As proved by geostatistics, this holds true for the whole territory of Baden-Württemberg.

Recommendation and Perspective

The effects of the rise of air temperature should be examined not only by monitoring of biological individuals as for example plants, but on ecosystem level, too. The German ecosystem research and the environmental monitoring should be supplemented by the study of the effects of the climatic change in ecosystems. Because air temperature and humidity have a great influence on the temporal and spatial distribution of pathogen carriers (vectors) and pathogens mapping of the determinants of vector and pathogen distribution in space and time should be done in order to identify hot spots for risk assessment and further detailed epidemiological studies.     

New methods for fast on-site measurement of odorous compounds

New methods for measurement of odorous gases, especially for aerosol-bound chemical compounds, have been developed in the Department of Measurement Technology (Technical University of Hamburg Harburg--MT-TUHH). Odorous compounds in the waste gases produced by the food industry were analysed based on high-volume aerosol sampling techniques, enrichment on solid phase micro extraction (SPE) cartridges and analytical measurement techniques using thermal desorption gas chromatography-mass spectrometry. The analysis results were compared to classic analytical procedures using adsorbence materials (Tenax) for enrichment. In comparison to aerosol sampling, analysis of Tenax samples was found to be ineffective, especially for analyzing polar semi volatile compounds. In addition, sensor arrays were also used in the study to characterize odors of different waste gases emitted by food production facilities. Measuring the odor units of the waste gas of a fat producing factory, the results of sensor-array-measurements show good correlation with results obtained with olfactometric measurements.