ESSENTIAL OIL OF CURCUMA LONGA L. RHIZOMES CHEMICAL COMPOSITION, YIELD VARIATION AND STABILITY

Turmeric (Curcuma longa L.) is a medicinal plant that is cultivated worldwide. This study was conducted to evaluate the variability in the percentage and the chemical composition of volatile oils from 12 turmeric samples. Rhizomes of the turmeric plant were collected from three different producers in the Brazilian like savanna (Cerrado) habitat in the state of Bahia. The chemical composition of the oils derived from the rhizomes was analysed by thin-layer chromatography and GC-MS. The average oil content was 3.97% ± 0.61%, varying from 3.0% to 5.16%. There were differences between producers; however, all samples met the specification of the Brazilian Pharmacopoeia. Thin-layer chromatographic analysis revealed qualitative similarity in both oil and curcuminoid components among the samples. The major components identified in the oils by gas chromatography were ar-turmerone (40.00% ± 13.20%), α-turmerone (10.05% ± 2.90%) and curlone (22.73% ± 12.72%). Regarding stability, there was a difference between the essential oil percentages after 6 months, but the content was maintained adequate and the chromatographic profile remained similar. The vegetable raw material obtained from C. longa rhizomes produced in the western region of the state of Bahia met the quality requirement of the Brazilian Pharmacopoeia.