ABSTRACT

The study investigated the nutrient composition and effect of aqueous extracts of ginger (Zingiber officinale) and lemongrass (Cymbopogon citratus) on the blood glucose and lipid profile of alloxan-induced hyperglycemic rats. The proximate, mineral and vitamin content of Zingiber officinale and Cymbopogon citratus extracts were investigated. Albino Wistar rats, 100-150g weight, fed on standard animal feed and water ad libitum were divided into six (6) groups of six (6) animals each. Group 1: Non-diabetic control rats, Group 2: Non-treated diabetic control rats, Group 3: Glibenclamide (anti-diabetic drug) treated diabetic rats, Group 4: Ginger-treated diabetic rats, Group 5: Lemongrass-treated diabetic rats, Group 6: Ginger-lemongrass-treated diabetic rats. Group 2, 3, 4, 5 and 6 were induced diabetes by intraperitoneal injection of 160mg/b/w of alloxan. Rats having blood glucose of 150 mg on day 3 (72 hours after alloxan injection) were considered diabetic and selected for the experiment. Blood samples was drawn from the tail of the rats and used to estimate the fasting blood sugar level day at 1, 7, 14 and 21 using a glucometer. On day 21, the animals were sacrificed by cervical dislocation, blood was collected by cardiac puncture and serum separated for lipid estimation. Data was statistically analyzed by Duncan’s post hoc and ANOVA. The proximate analysis showed that minerals and vitamin composition of the extracts (Zingiber officinale and Cymbopogon citratus) are good sources of nutrients with great potentials. The result obtained from the experiment showed that administration of aqueous ginger and lemongrass extracts significantly (p< 0.05) restored blood glucose level to normal when compared to the normal group. The group treated with ginger extract (400 mg/kg dose) showed a reduction (from 416.83±5.76 to 79.20±14) while the group treated with lemongrass extract of 400 mg/kg dose showed a reduction of blood glucose from 435.16 ± 41.35 to 73.00±13.60. Lemongrass and ginger extracts of 400 mg/kg dose for 21 days showed a reduction in the level of TC, TG and LDL-C, but elevated level of HDL concentration. Ginger and lemongrass extract exhibited hypocholesterolemic effect on the alloxan-induced diabetic rats. The weights of the rats after induction showed that the group treated with ginger extract, lemongrass extract, combined ginger and lemongrass extract and glibeanclamide (standard drug) significantly regained their weight by day 14. Weight increase progressed to day 21. This might be as a result of restoration of normal glucose metabolism. Findings in this study therefore showed that the administration of aqueous extracts of ginger (Zingiber officinale) and lemongrass (Cymbopogon citratus) has significant ameliorative effect on alloxan-induced hyperglycaemic and hyperlipidemic diabetic rats and this may be of immense benefits in the management of diabetes and its associated complications.