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Two new optically active phosphinopyrrolidine monomers were prepared by the reaction of (2S,4S)-4-(diphenylphosphino)-2-[(diphenylphosphino)methyl]pyrrolidine and (2ñ,4R)-4-(diphenylphosphino)-2-[(diphenylphosphino)methyl]pyrrolidine with acryloyl chloride to give IV-acryloyl-Copolymerization of 1 and 2 with hydrophilic comonomers and a divinyl monomer provided cross-linked insoluble polymers containing 3-5% of 1 or 2 that would swell in polar solvents. Exchange of rhodium® onto the polymer gave catalysts which were active for the asymmetric hydrogenation of jY-acyl «-amino acids in high optical yields, the phosphine derived from the enantiomer of the naturally occurring 4-hydroxyproline giving (S)-amino acids. The catalysts could be reused with no loss in selectivity by simple filtration.

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Escherichia coli O157:H7 is an important food-borne pathogen. Often E. coli O157:H7 is difficult to detect, because it is present sporadically at very low levels together with very high levels of competitor organisms which can be difficult to distinguish phenotypically. Cultural methods are time-consuming and give variable results in the detection of E. coli O157:H7. This study examined the performance of BAX for Screening/E. coli O157:H7, a new rapid method for the detection of E. coli O157:H7, against traditional and improved cultural methods and an immunodiffusion assay. All cultural methods demonstrated inadequacy in detecting the presence of E. coliO157:H7 in inoculated samples. The limitations of these cultural methods further complicate evaluation of screening methodologies. The BAX for Screening/E. coli O157:H7 assay outperformed the other methods, with a detection rate of 96.5%, compared to 39% for the best cultural method and 71.5% for the immunodiffusion method. The BAX for Screening/E. coli O157:H7 assay proved to be a rapid, highly sensitive test for the detection of low levels ofE. coli O157:H7 in ground beef.