Common bean (Phaseolus vulgaris L.) α-amylase inhibitors as safe nutraceutical strategy against diabetes and obesity: An update review

Overweight and obesity are constantly increasing, not only in Western countries but also in low-middle-income ones. The decrease of both the intake of carbohydrates and their assimilation are among the main dietary strategies to counter these conditions. α-Amylase, a key enzyme involved in the digestion of carbohydrates, is the target enzyme to reduce the absorption rate of carbohydrates. α-Amylase inhibitors (α-AIs) can be found in plants. The common bean, Phaseolus vulgaris is of particular interest due to the presence of protein-based α-AIs which, through a protein–protein interaction, reduce the activity of this enzyme. Here we describe the nature of the various types of common bean seed extracts, the type of protein inhibitors they contain, reviewing the recent Literature about their molecular structure and mechanism of action. We also explore the existing evidence (clinical trials conducted on both animals and humans) supporting the potential benefits of this protein inhibitors from P. vulgaris, also highlighting the urgent need of further studies to confirm the clinical efficacy of the commercial products. This work could contribute to summarize the knowledge and application of P. vulgaris extract as a nutraceutical strategy for controlling unwanted weight gains, also highlighting the current limitations.