ABSTRACT
Introduction: Medicinal plants have been reported to play an important role in modulating glycemic responses; they are also known to have preventive and therapeutic implications in disorders of carbohydrate and lipid metabolism. This study reports the possible hypoglycemic effects of Morus indica (Mulberry) and Costus speciosus (Insulin plant) in an in vitro system. Methods: Glucose adsorption, diffusion and starch hydrolysis of Mulberry leaf powder (MLP) and Insulin plant powder (IPP) were studied using in vitro techniques that simulated gastrointestinal conditions and compared with commercial dietary fibre sources such as wheat bran (WB), acarbose (ACB) and guar gum (GG) at three different levels (2, 4, and 6 %). Results: The glucose binding capacity of both Morus indica.L (MLP) and Costus speciosus (IPP)increased with increased levels and was significantly high compared to wheat bran and acarbose. At higher levels (4 and 6 %), the diffusion rate of glucose was lower compared to wheat bran, acarbose and guar gum. The a-amylase inhibitory effect was significantly high in MLP (51%) and IPP (18%) compared to WB (8%). The effect of samples on glucose diffusion was also studied in a system comprising of starch-a-amylase sample. The glucose diffusion rate was significantly low in the systems where MLP (6%) and IPP (6%) were used compared to the positive control and to commercial sources of fibre (ACB and GG). Conclusion: The data reveals that the samples may lower the rate of glucose absorption and as a result, decrease postprandial hyperglycemia by these mechanisms.