Rai Prashant K, Jaiswal Dolly, Mehta Shikha, Watal Geeta
Drug Development Division, Department of Chemistry, University of Allahabad, Allahabad, India.
Indian J Med Res. 2009 May;129(5):561-5.
BACKGROUND & OBJECTIVE: This study was undertaken to evaluate the glycaemic potential of aqueous extract of Psidium guajava unripe fruit peel on blood glucose level (BGL) of normal and streptozotocin induced mild and severely diabetic rats as an extension of our previous work carried out on Psidium guajava ripe fruit peel.
The aqueous extract of P. guajava unripe fruits was prepared. Male 6-8 wk old albino Wistar rats were selected for the experiments. Diabetes was induced by streptozotocin infection. Blood glucose levels were measured by glucose oxidase method. Antihyperglycaemic activity of the extract was assessed in mild and severely diabetic rats.
The maximum fall of 21.2 per cent (P<0.01) and 26.9 per cent (P<0.01) after 3 h of glucose administration during glucose tolerance test (GTT) was observed in BGL from a dose of 400 mg/kg, identified as the most effective dose, in normal and mild diabetic rats respectively. In severely diabetic rats the maximum fall of 20.8 and 17.5 per cent in fasting blood glucose (FBG) and post prandial glucose (PPG) levels, and 50 per cent (P<0.01) in urine sugar levels was observed with the same dose. Haemoglobin level increased by 5.2 per cent (P<0.05) and body weight by 2.5 per cent (P<0.05) after 21 days treatment.
INTERPRETATION & CONCLUSION: Normal, mild and severely diabetic rat models had shown hypoglycaemic as well as antidiabetic effect of the unripe guava fruit peel aqueous extract. Further studies need to be done to characterize the active components of the peel.
作为我们之前对番石榴成熟果皮所做研究的延伸，本研究旨在评估番石榴未成熟果皮水提取物对正常大鼠以及链脲佐菌素诱导的轻度和重度糖尿病大鼠血糖水平（BGL）的血糖影响。
制备番石榴未成熟果实的水提取物。选用6 - 8周龄的雄性白化Wistar大鼠进行实验。通过链脲佐菌素感染诱导糖尿病。采用葡萄糖氧化酶法测量血糖水平。在轻度和重度糖尿病大鼠中评估提取物的降血糖活性。
在葡萄糖耐量试验（GTT）中，给药葡萄糖3小时后，正常大鼠和轻度糖尿病大鼠中，剂量为400mg/kg（被确定为最有效剂量）时，血糖水平分别最大下降21.2%（P<0.01）和26.9%（P<0.01）。在重度糖尿病大鼠中，相同剂量下，空腹血糖（FBG）和餐后血糖（PPG）水平分别最大下降20.8%和17.5%，尿糖水平下降50%（P<0.01）。治疗21天后，血红蛋白水平升高5.2%（P<0.05），体重增加2.5%（P<0.05）。
正常、轻度和重度糖尿病大鼠模型均显示出番石榴未成熟果皮水提取物的降血糖和抗糖尿病作用。需要进一步研究以确定果皮中的活性成分。
