Biological Control: Isolation and Bacterial Oxidation of the Taste‐and‐Odor Compound Geosmin

Naturally occurring tastes and odors in water supplies have been attributed to a variety of microorganisms as the causative agents. In this regard, certain species of blue-green algae, particularly of the planktonic types, and the actinomycetes bacteria have been documented as the primary organisms responsible for the production of these metabolites. The study of such metabolities in water, however, has been primarily restricted to odors, since it was indicated by the AWWA Com. on Taste and Odors, organized in 1965, that taste as a specific sensory process is rarely a problem in water supply.1 In the review, the chemical data for the two most important of these microbial odor compoundsmucidione and geosminwere given by the committee in addition to descriptions of odortreatment methods such as the novel application of biological control techniques. One of the first considerations for biological control was reported by Silvey and Roach, who observed an interrelationship among various types of idigenous microorganisms in their studies of microbiotic cycles in surface waters.2 In this investigation the organisms appeared and attained peak populations during predictable periods of the year. However, it was noted in this observation that the actinomycete metabolites seemed to serve as a source of nutrition for the