A comprehensive review on influence of millet processing on carbohydrate-digesting enzyme inhibitors and implications for diabetes management

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.

Advances in the novel and green-assisted techniques for extraction of bioactive compounds from millets: A comprehensive review

Millets are rich in nutritional and bioactive compounds, including polyphenols and flavonoids, and have the potential to combat malnutrition and various diseases. However, extracting these bioactive compounds can be challenging, as conventional methods are energy-intensive and can lead to thermal degradation. Green-assisted techniques have emerged as promising methods for sustainable and efficient extraction. This review explores recent trends in employing green-assisted techniques for extracting bioactive compounds from millets, and potential applications in the food and pharmaceutical industries. The objective is to evaluate and comprehend the parameters involved in different extraction methods, including energy efficiency, extraction yield, and the preservation of compound quality. The potential synergies achieved by integrating multiple extraction methods, and optimizing extraction efficiency for millet applications are also discussed. Among several, Ultrasound and Microwave-assisted extraction stand out for their rapidity, although there is a need for further research in the context of minor millets. Enzyme-assisted extraction, with its low energy input and ability to handle complex matrices, holds significant potential. Pulsed electric field-assisted extraction, despite being a non-thermal approach, requires further optimization for millet-specific applications, are few highlights. The review emphasizes the importance of considering specific compound characteristics, extraction efficiency, purity requirements, and operational costs when selecting an ideal technique. Ongoing research aims to optimize novel extraction processes for millets and their byproducts, offering promising applications in the development of millet-based nutraceutical food products. Therefore, the current study benefits researchers and industries to advance extraction research and develop efficient, sustainable, and scalable techniques to extract bioactive compounds from millets.

Endosperm enzyme activity is responsible for texture and eating quality of cooked rice grains in Japanese cultivars

Eating quality of cooked rice grains is an important determinant of its market price and consumer acceptance. To comprehensively assess the variation of eating-quality traits in 152 Japanese rice cultivars, we evaluated activities of eight endosperm enzymes related to degradation of starch and cell-wall polysaccharides. Endosperm enzyme activities showed a wide range of variations and were lower in recently developed cultivars than in landraces and old improved cultivars. Activities of most endosperm enzymes correlated significantly with the eating-quality score and surface texture of cooked rice grains. Principal component analysis revealed that rice cultivars with high eating-quality scores had high stickiness of the grain surface and low levels of endosperm enzyme activities. These results suggest that endosperm enzyme activities control texture and eating quality of cooked rice grains in Japanese rice cultivars.