Millets, often overlooked as food crops, have regained potential as promising stable food sources of bioactive compounds to regulate blood sugar levels in the diabetic populace. This comprehensive review delves into various millet varieties, processing methods, and extraction techniques aimed at isolating bioactive compounds. The review elucidates the inhibitory effects of millet-derived bioactive compounds on key enzymes involved in carbohydrate metabolism, such as α-amylase and α-glucosidase. It further explores the relationship between the antibacterial activity of phenols, flavonoids, and anthocyanins in millets and their role in amylase inhibition. In particular, phenols, flavonoids, and proteins found in millets play pivotal roles in inhibiting enzymes responsible for glucose digestion and absorption. However, processing methods can either enhance or reduce the bioactive compounds, thereby influencing enzyme inhibition capacity. Studies underscore the presence of phenolic compounds with notable inhibitory activity in: foxtail, finger, barnyard, and pearl millet varieties. Furthermore, extraction techniques, such as Soxhlet and ultrasonic-assisted extraction, emerge as efficient methods for isolating bioactive compounds, thus enhancing their therapeutic efficacy. This review highlights the challenges in preserving the inhibitory activity of millets during processing and optimizing processing methods to ensure better retention of bioactive compounds. It also emphasizes the utilization of millet as a natural dietary supplement or functional food to manage diabetes and promote overall well-being.
Keywords: bioactive; diabetes; hyperglycemia; phytochemicals; α-Amylase; α-glucosidase.