Variation in the Chemical Composition of Five Varieties of Curcuma longa Rhizome Essential Oils Cultivated in North Alabama

Turmeric (Curcuma longa L.) is an important spice, particularly is Asian cuisine, and is also used in traditional herbal medicine. Curcuminoids are the main bioactive agents in turmeric, but turmeric essential oils also contain health benefits. Turmeric is a tropical crop and is cultivated in warm humid environments worldwide. The southeastern United States also possesses a warm humid climate with a growing demand for locally sourced herbs and spices. In this study, five different varieties of C. longa were cultivated in north Alabama, the rhizome essential oils obtained by hydrodistillation, and the essential oils were analyzed by gas chromatographic techniques. The major components in the essential oils were α-phellandrene (3.7-11.8%), 1,8-cineole (2.6-11.7%), α-zingiberene (0.8-12.5%), β-sesquiphellandrene (0.7-8.0%), ar-turmerone (6.8-32.5%), α-turmerone (13.6-31.5%), and β-turmerone (4.8-18.4%). The essential oil yields and chemical profiles of several of the varieties are comparable with those from tropical regions, suggesting that these should be considered for cultivation and commercialization in the southeastern United States.