Hypoglycemic Activity Of Different Parts Of Maize

Objective: To explore the hypoglycemic effective parts,effective components and mechanism of maize.Methods: The effective components of different parts of maize(whisker,straw skin,straw maize)were extracted by conventional physicochemical methods and systematic solvent methods,and the content of each effective component was determined.The stereoscopic model of α-glucosidase and α-amylase inhibitory activity was established to determine the hypoglycemic effective parts of maize.The hydroxyl radical method,DPPH method 、 ABTS+ and FRAP method were used to detect the four different antioxidant enzymes,The antioxidant activities of total flavonoids from different parts of maize were compared by chemical activity evaluation system.The potential Hypoglycemic Active Components in active parts of maize were identified by liquid chromatography-mass spectrometry(UF-LC-MS).The α-glucosidase and α-glucosidase inhibitory active components in total flavonoids from different parts of maize were screened based on ultrafiltration affinity technology.Objective to establish the in vitro activity screening model of insulin resistance(IR)Hep G2 cells and high glucose injured HUVEC cells,and determine the activity of potential active ingredients;to explore the effect of active ingredients of maize on IR-Hep G2 cell metabolism based on ~ 1H NMR.Results: In vitro enzyme activity inhibition test showed that the optimal conditions for inhibiting α-glucosidase reaction were p H 6.8,temperature 37℃,time 20min;the optimal conditions for inhibiting α-amylase reaction were p H 6.8,temperature 37℃,time10 min.The contents of total flavonoids(5.80~18.23%),total saponins(7.87~10.99%),total polysaccharides(24.48~35.36%)and total protein(9.41~13.02%)in different parts of maize were significantly different.The inhibitory effect of total flavonoids extracts from different parts of maize on α-glucosidase was significant,and the 50% inhibitory concentration of total flavonoids extracts from maize whisker,straw core and straw skin onα-glucosidase was higher than that from other parts(The IC50 of acarbose was 0.739 mg/ml,and the concentration of total flavonoids in silk,straw skin and straw core was 0.125~2mg/m L.The maximum inhibition rates of α-amylase were 36.41%,21.46% and 14.63%,respectively.The results of antioxidant experiment showed that the total flavonoids of maize stalk peel had strong reducingability and DPPH,ABTS+,·OH scavenging ability,and showed obvious dose-dependent,and the scavenging effect of corn stalk peel on ABTS+ was stronger than that of BHT.The active components of α-glucosidase andα-amylase in different parts of maize were screened by targeted affinity liquid chromatography-mass spectrometry,and the effective compounds in different parts of maize were identified as geranyl glucoside,5,7,4,-trihydroxy-3-methoxyflavone-3-c-arabinose-6-c-rhamnose,5,7,4,-The identified components of trihydroxyflavone-2-c-arabinose-6-c-glucose,6-C-β-rhamnopyranosyl-4’methoxyflavone-7-o-β-glucopyranoside and maize stalk core were trans-4’-methoxy-4-nitrochalcone,4’-methyl-epigallocatechin-3’-glucouronide,4’-methyl-epigallocat echin-3 ’-glucouronide,respectively,8-dimethoxy-epigallocatechin-3’-glucuronide,The glucose consumptionability of different parts of maize was determined by using the glucose consumption ability of IR-Hep G2 cells as the index.The results showed that the glucose consumption ability of different parts of maize could be improved in different degrees when the total flavonoids were 62.5~500μg/ml.The activities of GK and G-6-P were significantly increased(P<0.05)and decreased(P<0.05).The protective effects of total flavonoids from different parts of maize(62.5~500μg/ml)on HUVEC cells injured by high glucose were investigated.It was found that total flavonoids from different parts of maize could increase the contents of no and t-PA and decrease the contents of ET-1 and PAI-1 in varying degrees The difference was significant(P<0.05).the results of cell metabonomics showed that different parts of maize had hypoglycemic effects on IR-Hep G2 cells mainly by affecting glucose metabolism,energy metabolism and lipid metabolism.Conclusion: The crude extract of total flavonoids from different parts of maize should be the effective part of reducing blood sugar in different parts of maize by epnzyme activity test in vitro.The possible compounds in different parts of maize we-re speculated by liquid chromatography-mass spectrometry,and the potential α-amino-acids in total flavonoids from different parts of maize were preliminarily inferred bytargeted affinity liquid chromatography-mass spectrometry-Glucosidase and α-amylase inhibit active components.The insulin resistance model of human hepatoma cell line(Hep G2)was established.The results showed that the total flavonoids from different parts of maize could enhance the glucose consumption ability,and the protective effect of total flavonoids from different parts of Maize on the injury of human umbilical vein inner epidermal cells(HUVEC)in high glucose model;Total flavonoids from different parts of maize have hypogl-ycemic effect by affecting glucose metabolism,energy metabolism,lipid metabolisma-nd other ways.It is an effective choice for the prevention and treatment of diabetes.The pharmacodynamic components and potential mechanisms of total flavonoids fromdifferent parts of maize were preliminarily discussed.The experimental results provid-ea basis for the development of different parts of maize Reliable scientific basis.