A Comparison between The Effect of Black Tea and Kombucha Tea on Blood Glucose Level in Diabetic Rat

Diabetes mellitus is a metabolic disorder characterized by insufficient insulin secretion and/or insensitive target tissues to metabolic actions of insulin. Despite progressive efforts in production of synthetic drugs for treating diabetic patients there is a widespread propensity of patients to herbal medicine. Among these herbal remedies consumption of Kombucha tea (a solution of Kombucha mushroom cultivated in sweeted black tea) is relatively popular in some societies as an antidiabetic drink. On the other hand black tea (camellia sinensise) is a normal drink approximately in all societies. A casecontrol clinical trial study was conducted to evaluate the effect of black tea and Kombucha tea on blood glucose level in diabetic rats. In this study Wistar male rats with a free access to normal diet and lightdark cycle were used in room temperature of 22-25°C. Diabetes mellitus was induced on 15 rats by intraperitoneal injection of 60 mg/kg BW Streptozotocin. The diabetic animals (with blood glucose level equal or more than 300 mg/dl) divided equally into two groups. The animals in group 1 consumed black tea and in group 2 Kombucha tea instead of fresh water while animals in group 3 consumed fresh water. The blood samples were obtained from each animal in 3, 7 and 15 days after diabetic induction and blood glucose level in these stages relative to that in the onset of diabetes induction and were compared with each other. Our data showed that blood sugar level of both the black tea and Kombucha tea consuming diabetic rats declined significantly (p<0.01). The blood sugar of the control group however remained at normal levels (p<0.107). There was no significant differences between black tea and Kombucha tea groups (p<0.273). Therefore, if there is any antidiabetic effect in Kombucha tea, it seems to be due to some components of black tea which is the basic element in production of Kombucha tea.