Preparation and identification of an antioxidant peptide from wheat embryo albumin and characterization of its Maillard reaction products.

Wheat embryo albumin (WEA) extracted from wheat embryo possesses multiple effects including antioxidant, anti-inflammatory, and immunoregulatory effects. In this study, a single factor experiment was conducted to determine the optimal enzymolysis conditions of WEA. Five components (F1-F5) were obtained via ultrafiltration, among which F3 (molecular weight 3-5 kDa) displayed the best antioxidant activity. WEA and F3 were characterized by transmission electron microscopy, scanning electron microscopy, circular dichroism spectrum analysis, and amino acid composition tests. Results revealed that F3 significantly increased the contents of ß-tablets, aromatic amino acids, and hydrophobic amino acids compared to WEA. LC-MS/MS analysis demonstrated that F3 had more tyrosine and histidine moieties than WEA. Moreover, analysis of the Maillard reaction products (MRPs) showed that F3-MRPs had strong browning strength, ultraviolet absorption, higher number of free amino acids, and umami amino acid ratio compared with WEA. In conclusion, enzymolysis can improve the functional properties of WEA, which broadens the application spectrum of WEA in food and pharmaceutical fields. PRACTICAL APPLICATION: This study provides a new approach for identifying potential antioxidants and developing functional foods from WEA, and broadens the application spectrum of wheat germ resources.

In vitro dynamic digestion and anti-fatigue effects of wheat embryo albumin.

Wheat germ protein including wheat embryo albumin (WEA) demonstrates extensive biological activity. In vitro dynamic digestion of WEA was carried out under simulated gastrointestinal conditions. Anti-fatigue effects of WEA were evaluated using mice forced to swim. Results indicated that the digestibility of WEA decreased, antioxidant activity and the contents of aromatic amino acids (AAA) and hydrophobic amino acids (HAA) were significantly increased, and the ratio of essential amino acid (EAA) and non-essential amino acid (NEAA) were also changed during digestion. WEA significantly prolonged swimming time, reduced the accumulation of lactate dehydrogenase (LDH), blood urea nitrogen (BUN), and creatine kinase (CK). WEA also increased glycogen storage in liver and muscle. Meanwhile, WEA revealed antioxidant activity through enhancing the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) while decreasing the level of malondialdehyde (MDA). Notably, WEA enhanced the mRNA expression of mitochondrial biogenesis factors in the skeletal muscles of the mice. Therefore, WEA is suitable for preparation of energy foods with attractive anti-fatigue and health benefits.

Wheat embryo globulin nutrients ameliorate d-galactose and aluminum chloride-induced cognitive impairment in rats.

Wheat embryo globulin nutrient (WEGN), with wheat embryo globulin (WEG) as the main functional component, is a nutritional combination that specifically targets memory impairment. In this study, we explored the protective role of WEGN on Alzheimer's disease (AD)-triggered cognitive impairment, neuronal injury, oxidative stress, and acetylcholine system disorder. Specifically, we established an AD model via administration of d-galactose (d-gal) and Aluminum chloride (AlCl3) for 70 days, then on the 36th day, administered animals in the donepezil and WEGN (300, 600, and 900 mg/kg) groups with drugs by gavage for 35 days. Learning and memory ability of the treated rats was tested using the Morris water maze (MWM) and novel object recognition (NOR) test, while pathological changes and neuronal death in their hippocampus CA1 were detected via HE staining and Nissl staining. Moreover, we determined antioxidant enzymes by measuring levels of superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) in serum, cortex, and hippocampus, whereas changes in the acetylcholine system were determined by evaluating choline acetyltransferase (ChAT), and acetylcholinesterase (AChE) activities, as well as choline acetylcholine (Ach) content. Results revealed that rats in the WEGN group exhibited significantly lower escape latency, as well as a significantly higher number of targeted crossings and longer residence times in the target quadrant, relative to those in the model group. Notably, rats in the WEGN group spent more time exploring new objects and exhibited lower damage to their hippocampus neuron, had improved learning and memory activity, as well as reversed histological alterations, relative to those in the model group. Meanwhile, biochemical examinations revealed that rats in the WEGN group had significantly lower MDA levels and AChE activities, but significantly higher GSH, SOD, and ChAT activities, as well as Ach content, relative to those in the model group. Overall, these findings indicate that WEGN exerts protective effects on cognitive impairment, neuronal damage, oxidative stress, and choline function in AD rats treated by d-gal/AlCl3.