Data Views Total Plants: 102 CSV Excel PDF Total Activities: 5 , Previous123456 Show all rows. Paginate rows. Click on column headings to sort table by that column Plant Part All Bark Bulb Essential Oil Flower Fruit Fruit Juice Leaf Pericarp Petiole Plant Rhizome Rhizome Essent. Oil Seed Shoot Twig Wood Jf Low PPM High PPM StdDev *Reference Zingiber officinale Rhizome -- -- * Zingiber officinale Rhizome Essent. Oil -- -- * *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.