Data Views Total Plants: 1 CSV Excel PDF Click on column headings to sort table by that column Plant Part Low PPM High PPM StdDev *Reference Withania somnifera Root -- -- Hutchings, A, Scott, AH, Lewis, G, and Cunningham, A. 1996. Zulu Medicinal Plants. An inventory. University of Natal Press, Pietermaritzburg. 450 pp. *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.