Agricultural chemicals, optically active

Microelectronic circuits for communications. Controlled permeability films for drug delivery systems. Protein-specific sensors for the monitoring of biochemical processes. Catalysts for the production of fuels and chemicals. Optical coatings for window glass. Electrodes for batteries and fuel cells. Corrosion-resistant coatings for the protection of metals and ceramics. Surface active agents, or surfactants, for use in tertiary oil recovery and the production of polymers, paper, textiles, agricultural chemicals, and cement. 

Synthetic pyrethroids now account for at least 30% of the world insecticide market and are rapidly replacing other agricultural chemicals for control of insect pests. Fenvalerate is one of the more widely used synthetic pyrethroid insecticides. It is derived from a combination of a-cyano-3-phenoxybenzyl alcohol and a-isopropyl phenylacetate ester. Technical fenvalerate is a mixture of four optical isomers, each occurring in equal amounts but with different efficacies against insect pests. Fenvalerate does not usually persist in the environment for >10 weeks, and it does not accumulate readily in the biosphere. Time for 50% loss (Tb 1/2) in fenvalerate-exposed amphibians, birds, and mammals was 6 to 14 h for reptiles, terrestrial insects, aquatic snails, and fish it was >14 h to <2 days and for various species of crop plants, it was 2 to 28 days. Fenvalerate degradation in water is due primarily to photoactivity, and in soils to microbial activity. Half-time persistence in nonbiological materials is variable, but may range up to 6 days in freshwater, 34 days in seawater, 6 weeks in estuarine sediments, and 9 weeks in soils. 

Use of Microorganisms and Enzymes in the Synthesis and Production of Optically Active Agricultural Chemicals... 

CALTON Production of Optically Active Agricultural Chemicals... 

Development of microbial and enzymatic systems for production of natural product chemistry for agriculture, including pesticides, secondary metabolites (e.g. bialaphos, with herbicidal activity), optical isomers, specialty chemicals, etc. 

The production of both specialty and cammodlty chemicals by enzyme reaction has become a reality due to recent advances In Immobilization. These Immobilization techniques have provided an econcmlcal system for reuse of enzyme and thus provide a route to optical Iscmiers In high enantiomeric yields. This provides specific stereoisomers for agricultural synthesis at reasonable cost. The advantages of stereoisomers Include high activity levels as well as reduced toxicity due to the absence of the Incorrect stereoisomer. Methods of Immobilization will be reviewed with emphasis on Immobilization by polyazetldlne. Enzymatic reaction via immobilization enzymes and Immobilized whole cells will be reviewed with emphasis on the production of agrlcultaral chemicals. 

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