Anti-hyperglycemic activity of polyphenols isolated from barnyard millet (Echinochloa utilis L.) and their role inhibiting α-glucosidase

Abstract

The extracts and chemical compounds isolated from barnyard millet (Echinochloa utilis) grains were investigated as part of a search for naturally derived antihyperglycemic medicinal plants. Among the five different solvent extracts, the ethyl acetate extract showed the lowest IC 50 value against Saccharomyces cerevisiae a-glucosidase (70.2 lg/mL). Chromatography yielded eight phenolic compounds that may have been responsible for this effect. Among them, N-p-coumaroyl serotonin (1, CS), feruloyl serotonin (2, FS), and luteolin (5) potently inhibited aglucosidase with IC 50 values of 1.3-17.8 lM compared with those of deoxynojirimycin (DNJ, IC 50 = 2.5 ± 0.1 -lM) and acarbose (IC 50 = 255.1 ± 15.6 lM). Additionally, for the first time, we found that CS and FS were significantly inhibited mammalian rat intestinal sucrase (IC 50 of 3.0 and 8.2 lM) and reduced glucose content (73 and 52 % at 0.1 mg/wells) in Caco-2 (human intestinal epithelial) cells. Furthermore, oral glucose tolerance test revealed improved glucose tolerance following treatment with the barnyard millet grains extract by retarding the postprandial rise in blood glucose in vivo. These results suggest that barnyard millet grain can be used as a natural functional medicine to prevent and alleviate type-2 diabetes.

Isolation, characterization and in silico docking studies of synergistic estrogen receptor and #945; (ER and #945;) anticancer polyphenols from Syzygium alternifolium (Wt.) walp.

“…In the recent past, various researchers derived polyphenols from various medicinal plants to prove different biological activities such as anti-inflammatory [ 8 ], antibacterial [ 9 ], anticancer [ 10 ], antihyperglycemic [ 11 ], antimutagenic [ 12 ], antioxidant [ 13 ], hepatoprotective [ 14 ], and wound healing activities [ 15 ]. Thereafter, the exponential biologically active polyphenols were isolated from processed foods/drinks such as vanillic acid, gallic acid, caffeic acid, ferulic acid, and hydroxyphenylacetic acid from Origanum vulgare , Camellia sinensis , Prunus virginiana , Thymus vulgaris , and Olea europaea , respectively, showed synergistic biological activities [ 16 ].…”

Effect of Different Processing Methods on the Millet Polyphenols and Their Anti-diabetic Potential

“…The methanolic extract of finger millet and kodo millet protected collagen from glycation, thus possibly alleviating a complication of diabetes (47). Furthermore, Np-coumaroyl serotonin, feruloyl serotonin, and luteolin in the polyphenols from barnyard millet effectively inhibited αglucosidase activity (48). Therefore, polyphenols in millet can positively affect glucose metabolism disorders and contribute to glucose homeostasis (49,50).…”

Genetics and Genomics Interventions for Promoting Millets as Functional Foods

“…The extracts from barnyard millet were found to inhibit the activity of α-glucosidase of Saccharomyces cerevisiae [ 16 ]. Out of eight phenolic extracts from barnyard millet, N-p-coumaroyl serotonin (CS), feruloyl serotonin (FS), and luteolin displayed the α-glucosidase inhibitory activity.…”

“…Out of eight phenolic extracts from barnyard millet, N-p-coumaroyl serotonin (CS), feruloyl serotonin (FS), and luteolin displayed the α-glucosidase inhibitory activity. The CS and FS had the potential to decrease intestinal sucrase activity and reduced the glucose content in Caco-2 (human intestinal epithelial) cells [ 16 ]. The combination of millet and wheat flours has significantly lowered the blood glucose level compared to wheat flour alone [ 17 ].…”