Data Views Total Plants: 3 CSV Excel PDF Total Activities: 13 Click on column headings to sort table by that column Plant Part All Rhizome Rhizome Essent. Oil Root Low PPM High PPM StdDev *Reference Curcuma longa Rhizome 740.0 5800.0 * Curcuma longa Rhizome Essent. Oil 183800.0 596870.0 * Curcuma longa Root -- -- * *Unless otherwise noted all references are to Duke, James A. 1992. Handbook of phytochemical constituents of GRAS herbs and other economic plants. Boca Raton, FL. CRC Press.