Pengaruh Ekstrak Daun Teh Hitam Terhadap Kadar Gula Darah Sewaktu Pada Tikus Wistar Jantan Model Diabetes Mellitus

Diabetes mellitus (DM) is a metabolic disorder characterized by hyperglycemia due to impaired insulin secretion or insulin action. Long-term antidiabetic therapy may cause adverse effects, supporting investigation of natural products for glycemic control. Black tea leaf extract contains bioactive compounds with potential antihyperglycemic activity. This study aimed to determine its effect on random blood glucose (RBG) and compare doses of 100 and 200 mg/kg body weight in male Wistar rats with DM. A true experimental pre-test–post-test control group design was used. The population consisted of adult male Wistar rats used as a DM model. Twenty-four rats were selected by simple random sampling and divided into four groups of six: healthy control, diabetic control, 100 mg/kg extract, and 200 mg/kg extract. The independent variable was black tea leaf extract administration and the dependent variable was RBG level. Diabetes was induced with alloxan 150 mg/kg body weight, followed by oral extract administration for seven days. RBG was measured from tail blood using a digital glucometer. Data were analyzed using Shapiro–Wilk, Levene, One-Way ANOVA, and Tukey Post Hoc tests; ethical approval No. 72/EC/KEPKUGJ/V/2026 was obtained. Mean RBG reductions were 150.7 mg/dL at 100 mg/kg and 163.3 mg/dL at 200 mg/kg, compared with 3.3 mg/dL in the diabetic control. One-Way ANOVA showed a significant difference among groups (p=0.001), while Tukey analysis showed a significant difference between the two doses (p=0.041). Black tea leaf extract reduced RBG in diabetic male Wistar rats, with the 200 mg/kg dose producing a greater effect.