Anti- diabetic and Antioxidant Effects of Grapefruit, Mango and Strawberry Juice in Streptozotocin – Induced Diabetic Rats

Aim: The aim of the present study is to evaluate the phytochemical screening of mango, grapefruit and strawberry juice using HPLC and to investigate the anti- diabetic and antioxidant effects of grapefruit, mango and strawberry juice in streptozotocin – induced diabetic rats

Methodology: Mango, grapefruit and strawberry juice were orally administered at a dose of 1ml/100g body weight/day to streptozotocin - induced diabetic rats for four weeks. Blood samples were collected for analysis of Serum triglycerides (TAG), glucose, Insulin, total lipid (TL), total cholesterol (TC), low-density lipoprotein (LDL) and high-density lipoprotein (HDL) in diabetic rats compared with control negative rats and diabetic rats fed on different fruit juice.

Results: The results showed that mango has the highest levels of protein, crude fiber, ash content and total carbohydrates (0.82, 0.72, 0.51 and 9.61 g/100g fresh weight) followed by strawberry (0.50, 0.35, 0.27 and 8.95 g/100g fresh weight) and grapefruit was 0.40, 0.25, 0.19 and 8.76 g/100g fresh weight, respectively. There was no significant difference the pH at 20 ºC, titratable acidity (TA) g/L, total soluble solids (TSS oBrix), Vit. C. mg/100g and density g/cm (at 20ºC) between different fruit juices. Results also revealed that all fruit juices had rich content of the polyphenols and the results also illustrated that the mango, grapefruit, and strawberry juice oral adminstration decreased serum triglycerides (TAG), serum glucose, serum insulin, total lipid (TL), total cholesterol (TC), low-density lipoprotein (LDL) and MDA in diabetic rats. On the other hand, oral administration of fruit juices significantly increased serum HDL- cholesterol and modified oxidative stress.

Conclusion: From the obvious results, we can conclude that the grapefruit, mango, and strawberry juice have a strong antioxidant and hypolipidemic effects which might be attributed to their high polyphenols and flavonoid content.