Biotransformation of Monoterpenes by Polyurethane Foam-Immobilized Cells of Petroselinum crispum

Cells o f Petroselinum crispum cv. “Paramount” and “Plain-leaved” immobilized in polyure­ thane foam retained the biotransformational characteristics o f their freely suspended cells for certain monoterpenic substrates. Immobilized cells o f both cultivars were more efficient than their free cells in isomerizing geraniol into nerol, but less efficient (<60% ) in reducing the alde­ hydes, citral and citronellal. Maintenance o f the immobilized cells under the condition of growth limitation did not enhance the efficiency o f the biochemical reactions. Under the same condition, the freely suspended cells o f cult. “Paramount” exhibited higher efficiency (up to 1.6 times) o f biotransformation o f citral when compared to those in sucrose-supplemented me­ dia. This investigation lends support to the view that the biochemical productivity of cultured plant cells for especially monoterpenoids may not necessarily be improved upon immobiliza­ tion.