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The properties of a frugal laccase have been exploited to develop two enzyme assays for the phenolic content of natural beverages: first, by monitoring the fall in oxygen tension after addition of enzyme to a diluted juice sample in an end-point batch assay; second, by monitoring the current due to reduction of products after injection of sample into a flow injection analysis (FIA) system which incorporates the immobilized enzyme. Using apple juices, a linear (R>0.9) correlation was observable between these enzyme assays and the Folin-Ciocalteu wet chemical assay for total phenol content. Using purified substrates, a study has been made of those phenolic constituents measured in the two enzyme assays. Oxidative treatment of juices with laccase was shown by HPLC to specifically remove these phenolics

Matrix-inolated mono- and dichlorocyclopropenylidene have been generated by high-vacuum flash pyrolysis from di- and trichlorocyclopropenes. By subsequent photolysis they have been isomerized to the corresponding vinylidenecarbenes and propargylenes. The identification of six new carbenes in based on the comparison of their experimental and calculated (MP2/6-31G * ) infrared spectra. All have singlet electronic ground states

Photochimie du carbenacyclopropene prepare par pyrolyse du cyclopropene-2dipercarboxylate-1,1 de di-t-butyle