Diabetes has become the most common metabolic disease worldwide. In particular, type 2 diabetes is the most commonly encountered type of diabetes, which is characterized by impaired insulin secretion and/or action. One of the effective methods to control diabetes is to inhibit the activity of α-amylase and α-glucosidase enzymes which are responsible for the breakdown of starch to more simple sugars, using plant products. This study evaluated the total phenolic (TPC), total flavonoid (TFC), and

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... ntidiabetic potential of Thymus schimperi and Thymus vulgaris via in vitro inhibition of α-amylase and α-glucosidase, using the hot water and aqueous: methanol (20:80, v/v) extracts. The α-amylase inhibitory potentials of the extracts were investigated through reducing sugars analysis using 3,5-dinitrosalicylic acid color reagent (DNSA) using starch solution as substrate. The α-glucosidase inhibition was determined by pre-incubating α-glucosidase with different concentrations of the extracts followed by the addition of p-nitrophenylglucopyranoside (pNPG). Aqueous: methanol (20:80, v/v) extract of T. schimperi contained highest TPC (46.01 ± 4.54 mg GAE/g dw) and TFC (14.72 ± 1.14 mg QE/g dw) also showed stronger α-amylase inhibition activity (IC50 = 0.33 ± 0.05 mg/mL) and the hot water extract exhibited stronger α-glucosidase inhibition (IC50 = 0.05 ± 0.01 mg/mL) capacity than that of T. vulgaris. The TPC and TFC were positively related (p < 0.05) with α-amylase inhibition activity but negatively correlated (p > 0.05) with α-glucosidase inhibitory activity. These results indicated that the inhibition of these enzymes can lead to lower postprandial blood glucose.