A New Mint (Variety of Mentha aquatica L.) Containing (—)-Isopinocamphone as a Major Constituent of Essential Oil

Certain strains of Rhodotorula were found capable of utilizing L-phenylalanine as a sole carbon and nitrogen source and of accumulating ether-soluble metabolite in the cultured broth. The metabolite was isolated and identified as trans-cinnamic acid. The nonoxidative deamination of phenylalanine to trans-cinnamic acid was catalyzed by dried cells, acetone-dried cells or intact cells with surface active agents. The distribution of phenylalanine ammonia-lyase activity in yeasts was investigated. It was found that the enzyme activity specifically occurred in Rhodotorula and that the formation of enzyme was enhanced by culturing on the medium supplemented with phenylalanine.