Chemical efficiency

White, E. H., Rapaport, E., Seliger, H. H., and Hopkins, T. A. (1971). The chemi- and bioluminescence of firefly luciferin an efficient chemical production of electoronically excited states. Bioorg. Chem. 1 92-122. 

Europe is still the main market for leather products and leather produced in the developing countries, e.g. Southeast Asia, may therefore end up on the European market and to European consumers. Chemicals that are added during the production, and which stay on/in the product, will hence be transported by the product to the final markets, and there will be a chemical flow around the world through the transport of leather and leather products containing chemicals. Since the tanning industry is a chemically intensive industry, an efficient chemical management in tanneries is necessary in order to minimise the overall use of chemicals and in particular also to reduce the amount of hazardous chemicals used in order to minimise eventual health effects on the consumer. 

There are several initiatives and actions in order to control and stimulate a more efficient chemical management in the tanning sector. The main incentives are environmental legislations and customer requirements. The customer requirement can be expressed as either eco-labels or restriction substance lists (RSL) of chemicals in the products developed by major brands or several industrial groups. 

One example for a chemically defended zooplankton species is the Antarctic pteropod Clione antarctica. This shell-less pelagic mollusk offers a potentially rich source of nutrients to planktivorous predators. Nonetheless fish do not prey on this organism, due to its efficient chemical defense. In a bioassay-guided structure elucidation, pteroenone 37 could be isolated and characterized as the main defensive principle of C. antarctica [82,83]. If embedded in alginate, this compound is a feeding-deterrent in nanomolar concentrations. This unusual metabolite is likely to be produced by C. antarctica itself and not accumulated from its food, since its major food sources did not contain any detectable quantities of 37. 

Figure 16 Fluorophores with efficient chemical excitation in the PO-CL reaction. TMP, 2,4,6,8-tetrathiomorpholinopyrimido 5,4-rf pyrimidine DTDCI, 3,3 -diethylthiadicarbo-cyanine iodide.

Vol. 3 (2007/3) New Avenues to Efficient Chemical Synthesis Editors P.H. Seeberger, T. Blume... 

Sun, Z., et al., A highly efficient chemical sensor material for H2S a-Fe203 nanotubes fabricated using carbon nanotube templates. Advanced Materials, 2005.17(24) p. 2993-2997. 

Seeberger PH, Blume T. New Avenues to Efficient Chemical Synthesis Emerging Technologies—Proceedings 06.3, Springer-Verlag, Berlin, 2007. 

Here, we describe, as a representative example, an efficient chemical synthesis of 4-fluorophenylpyruvic acid (Procedure 1, Section 10.5.1) followed by its biocatalytic conversion to L-4-fluorophenylalanine catalysed by the N145V mutant of PheDH (Procedure 2, Section 10.5.2). 

The extensive use of enzymatic catalysts in organic synthesis has been documented [10], Enzymes represent a broad range of efficient chemical catalysts. They are classified mainly into six categories ... 

By far the most efficient catalysts are enzymes, which regulate most biological reactions. Biological catalysts are without question the most important catalysts (to us) because without them life would be impossible. Enzymes are proteins that may be either isolated molecules in solution (homogeneous) or molecules bound to large macromolecules or to a cell wall (heterogeneous). We have not yet learned how to create catalysts with nearly the efficiency and selectivity of nature s enzyme catalysts. We will consider biological reactors at the end of this chapter as the example of the most efficient chemical reactor possible. 

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