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To investigate the characteristics of growth and oil production of peppermint cells during a batch culture, cells derived from peppermint callus was cultivated in an air bubble reactor. During the batch culture, effects of inoculum size, abiotic stress, yeast elicito;two stage culture on the cell growth, the productivity of oleolesin, and the formation of flavor components were determined and also the sugar concentrations and kinetics of cell growth were analyzed. Among the various sizes of inoculum, the culture with 2.0% packed cell volume inoculum showed the optimum condition for cell growth in the proposed bioreacto;the cell yield and essential oil production reached to 5.8g/8 and 0.109g/8 , respectively. When the abiotic stress of daily 8hr dark and 10°C cold treatments were given to the culture, cell growth decreased but essential oil production increased to 0.546g/e . In a modified Lin-Staba medium in which 100mg/Q yeast extract as an elicitor was added to the culture, the cell growth and oil production increased, and menthol content was 22.5% of oil. In the two stage culture, in which the basic culture conditions of 271C, light, and without elicitor were employed during the first six days followed by the second stage with daily 8hr treatment of cold and dark condition, and also with yeast extract as an elicito;cell growth decreased after eight days, essential oil production was not increased, and menthol was not detected. Dry cell yield was 0.38 g dry cell/g sugar and specific growth rate was 0.25 day-´. The major terpenoid in the oil was not the menthol but pulegone and piperitone, precursors of menthol were accumulated. Howeve;when yeast elicitor was added, menthol was produced to the level of 22.5% which was the highest value in the peppermint cell culture reported so far.
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