Effect of aqueous and ethanol extracts of Cassia auriculata L. flowers on diabetes using alloxan induced diabetic rats

In the present study the antidiabetic potential of aqueous and ethanol extract of Cassia auriculata L. flowers was assessed in alloxan-induced diabetic rats. The phytochemical screening and antioxidant activity were made in these extracts. Antidiabetic agents (Flavonoids and phenolic acids) and free radical scavenging activity in water-soluble fraction of the ethanol extract was higher compared to that of aqueous extract. Diabetic rats showed increase in blood glucose (p<0.01) and decrease in plasma insulin (p<0.01) levels after 48 hrs of alloxan administration. The oral administration of water-soluble fraction of the ethanol extract at a dose of 0.25 and 0.5g/kg of body of weight, for 30 days exhibited a significant (p<0.001) reduction in the blood glucose level and a remarkable increase in plasma insulin level compared to the aqueous extract-treated rats and diabetic control. The level of serum triglycerides and total cholesterol were significantly (p<0.01) increased in diabetic rats. The marker enzymes of liver toxicity such as serum alanine transaminase (ALT), serum aspartate transaminase (AST), serum acid phosphatase (ACP), and serum alkaline phosphatase (ALP) were elevated significantly (p<0.01) in diabetic control. The liver glycogen and glycogen synthase levels were also increased significantly (p<0.01) in alloxan-induced diabetic rats. In addition changes in the body weight and food intake were also analyzed in diabetic and the extracts-treated rats. Treatment with water soluble fraction of ethanol extract and aqueous extract of C. auriculata flowers restored the above altered parameters significantly in diabetic animals. The water soluble fraction of the ethanol extract showed a more efficient antihyperglycemic effect compared to the aqueous extract.