Cation exchange column chromatography was investigated for simple and efficient separation of lysozyme from homogenized egg white. A macroporus weak acid type resin, Duolite C-464, was selected based on high lysozyme recovery in the 90-95% range, retention of whipping and gelling properties in the lysozyme-separated egg white, and ease of column operation. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate indicated high purity of the recovered lysozyme and simultaneous recovery of avidin under the eluting conditions used. The process for lysozyme separation from egg white using Duolite C-464 is suitable for operation in an automated, continuous mode.

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A practical guideline for community-level ecological risk management is proposed, with particular emphasis on the mutual interdependencies of the scientific analysis, public consensus building, and an adaptive management. The procedure we recommend spans the screening of potential ecological risks, the involvement of related stakeholders, the conceptual development from the ''undesired event'' over assessment endpoints to measures of effect and stress factors, the risk assessment for the no-action case, the planning phase from the public decision to become active and the setting of goals over a specification of monitoring and control methods to an assessment of feasibility and a public approval of the management plan and finally the adaptive management from initiation over continued monitoring to revisions of the plan, if required. The procedure contains several checkpoints, alternative routes, and possibilities to correct previous decisions.

Molecularly imprinted cavities have functioned as a regioselective reaction field for the [4 + 4] photocyclodimerization of 2-anthracenecarboxylic acid (2-AC). Molecularly imprinted polymers were prepared by precipitation polymerization of N-methacryloyl-4-aminobenzamidine as a functional monomer to form a complex with template 2-AC and ethylene glycol dimethacrylate as a crosslinking monomer. The 2-AC-imprinted cavities thus constructed preferentially bound 2-AC with an affinity greater than that toward structurally related 9-anthracenecarboxylic acid, 2-aminoanthracene, and unsubstituted anthracene. Moreover, from the four possible regioisomeric cyclodimers, they mediated the [4 + 4] photocyclodimerization of 2-AC specifically to the anti-head-to-tail (anti-HT) isomer. This indicates that the imprinted cavities accommodate two 2-AC molecules in an anti-HT manner, thereby facilitating the subsequent regioselective photocyclodimerization.

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