The genus Curcuma consists of nearly hundred & thirty accepted species in the family Zingiberaceae. Turmeric is a perennial herb spread across tropical and sub-tropical regions like India, Pakistan, Bangladesh and Sri Lanka.
The turmeric producing regions in India are Salem and Erode in Tamil Nadu; Alleppy, Wayanad in Kerala; Sangli and Marathwada in Maharashtra; Nizamabad in Andhra; Cuddappah in Telangana; Gundelpet in Karnataka; Kandhamal in Orissa and the North eastern states of Meghalaya, Assam & Sikkim.
Curcumin, demethoxycurcumin and bisdemethoxycurcumin referred to as curcuminoids are the major polyphenolic compounds in turmeric. Environmental factors such as minimum relative humidity, altitude, soil nitrogen content and soil pH contributed to the varying curcumin content of the different varieties of turmeric. The pale yellow to orange-yellow volatile oil of turmeric consists of a number of mono- and sesquiterpenes referred to as curcumenone.