Gas chromatographic – mass spectrometry profile and comparative anti-diabetic properties of Curcuma longa and Curcuma domestica (Zingibereacae) essential oils collected from Nigeria

Curcuma longa and Curcuma domestica rhizomes applies in ethno-medicine for the management of several diseases including gastric ulcer, jaundice, diabetes etc [1 – 2]. The contribution of the essential oils in the management of diabetes mellitus is the thrust of this study. Essential oil of the fresh rhizomes of C. longa (CLEO) and C. domestica (CDEO) were obtained by hydro-distillation using Clevenger-type apparatus. Their anti-diabetic property were assessed using alloxan (150 mg/kg, i.p) induced diabetic rats. Blood glucose levels were monitored using Glucometer. Only animals with glucose level > 160 mg/dl were qualified and were distributed into eight groups (n = 5) each. Group I received 5% Tween 80 (vehicle), groups II-IV received CLEO (50, 100 and 200 mg/kg respectively), while groups V-VII similarly received CDEO. Group VIII animals received glibenclamide (5 mg/kg). All administration was done orally and daily for 14 days. CLEO caused a time dependent reduction of blood glucose level in the test groups. A complete reversal of diabetes from 396.2 ± 85.0 mg/dl to 60.2 ± 12.1 mg/dl was however obtained for the group II animals which compares with the effect produced by glibenclamide (70.4 ± 3.9 mg/dl) within two weeks of treatment. CDEO also showed a significant reduction of blood glucose levels of group VI treated animals from 451 ± 65.5 mg/dl to 68.4 ± 7.3 mg/dl. The activities of the liver enzymes and the serum lipids of the animals reduced significantly (P < 0.001) while the high density lipoprotein also increased significantly (p < 0.05) in all the tested groups compared to standard agent. The chromatographic profiling by GC-MS analysis identified eucalyptol, α-caryophyllene, tumerone and α-farnesene as some of the common constituents found respectively in CDEO and CLEO. The study demonstrated that volatile oil of the two Curcuma spps possessed comparable anti-diabetic properties. It also provided information on the hepatoprotective and anti-lipidemic potentials of the oils.

Keywords: Essential oils, Curcuma spp, GC-MS, anti-diabetic, anti-lipidemic, hepatoprotective

References:

[1] Kuo ML, Huang TS, Lin JK, Curcumin, an antioxidant and anti-tumor promoter, induces apoptosis in human leukemia cells. Biochim Biophys Acta 1996; 1317: 95 – 100.

[2] Wickenberg J, Ingemansson SL, Hlebowicz J. Effects of Curcuma longa (tumeric) on postprandial plasma glucose and insulin in healthy subjects. Nutrition J 2010; 9: 43.