Free and Bound Phenolic Compound Content and Antioxidant Activity of Different Cultivated Blue Highland Barley Varieties from the Qinghai-Tibet Plateau

Effect of different thermal treatments on starch digestion of Tsamba (Highland barley products): Insights from starch structural properties and enzyme activity

This study elucidated the mechanisms involved in the impact of Tsamba (a highland barley product) starch digestibility by different thermal treatments. The results demonstrate that different thermal processing methods (microwave, roasting, sand frying, frying, baking, and steaming) significantly alter the polyphenol content of highland barley, which in turn affects its ability to inhibit α-amylase activity. SEM, CLSM, XRD and FTIR were used to evaluate the effects on starch microstructure and digestibility. The microstructure, short-range order, and crystalline structure of starch would modify after different thermal treatments. Notably, the starch structure with the least disruption and improvement in resistance to enzyme hydrolysis suggests that microwaves may be an effective way to produce foods with higher resistant starch content. This study provides valuable insights into dietary strategies for the management of starch digestibility in people with diabetes.

Bolanthus turcicus: a promising antidiabetic with in-vitro antioxidant, enzyme inhibitory and antiadipogenic activities

It is crucial to investigate new anti-diabetic agents and therapeutic approaches targeting molecules in potential signaling pathways for the treatment of Type 2 diabetes mellitus (T2DM). The objective of the study was to investigate the total phenolic content, antioxidant capacity, α-glucosidase, and α-amylase inhibitory activities of Bolanthus turcicus (B. turcicus), as well as their cytotoxic, anti-adipogenic, anti-diabetic, apoptotic, and anti-migration potential on adipocytes. B. turcicus samples were extracted with methanol (MeOH), ethyl acetate (EA) and aqueous (Aq) solvents. The MeOH extract had the highest phenolic content (81.14 mg GAE/g), followed by EA (74.93 mg GAE/g) and Aq (51.09 mg GAE/g). All extracts exhibited dose-dependent increases in α-glycosidase and α-amylase inhibitory activity. B. turcicus extracts showed cytotoxic effect on adipocytes with IC50 values of MeOH (141.0 µg/mL) < Aq (155.3 µg/mL) < EA (199.5 µg/mL). Furthermore, B. turcicus extracts reduced lipid droplet formation and adipocyte diameter size. All extracts altered cell morphology to resemble fibroblasts. B. turcicus extracts exhibited anti-migratory effect delaying wound healing for up to 96 h. The B. turcicus extracts showed a pro-apoptotic effects on adipocytes by increasing Caspase-3 enzyme activity and the population of DAPI-positive cell with apoptotic nuclear-morphology. B. turcicus extracts upregulated the expression of the Glut-4 gene at the mRNA, protein and intracellular level in adipocytes. In conclusion, our findings indicate that B. turcicus not only exhibits strong antioxidant properties and enzyme inhibitory activities but also exerts significant anti-adipogenic and pro-apoptotic effects in adipocytes, thereby providing a comprehensive mechanism through which it may contribute to the management of T2DM. These effects highlight the potential of B. turcicus as a therapeutic agent for improving glucose homeostasis and insulin sensitivity.

Effects of Pretreatment Methods on Gamma-Aminobutyric Acid Enrichment and Quality Improvement in Highland Barley Beverages

Gamma-aminobutyric acid (GABA) is an important neurotransmitter that promotes sleep and reduces anxiety, but its natural synthesis in the body is insufficient, necessitating dietary intake. This study utilized a combination of germination, the addition of active barley powder, and fermentation to enhance GABA content in an enzymatically hydrolyzed highland barley beverage. The samples were divided into five groups: highland barley (HB), germinated highland barley (GB), highland barley supplemented with another high-glutamic-acid decarboxylase-active highland barley powder TB13 (BT), germinated barley supplemented with TB13 (GBT), and germinated barley supplemented with TB13 followed by fermentation (GBTF). The results indicated that all the pretreatments significantly elevated GABA levels, with the GBT sample showing the highest GABA content, which was 2.4 times that of the HB sample. Germination had minimal impact on the taste and aroma of the beverage, while the addition of TB13 active barley powder caused only slight changes to the aroma. The GABA content in the GBTF sample was 2.2 times higher than in the HB sample, and the GBTF sample also exhibited the highest total phenolic content, demonstrating the strongest antioxidant and free-radical scavenging abilities. Furthermore, the GBTF treatment increased acidity, reduced bitterness, and significantly altered the flavor profile of the barley beverage, enhancing its overall quality and consumer appeal as a GABA-rich functional drink.

Review on mechanisms of hypoglycemic effects of compounds from highland barley and potential applications

The rising prevalence of metabolic diseases, such as diabetes and obesity, presents a significant global health challenge. Dietary interventions, with their minimal side effects, hold great promise as effective strategies for blood sugar management. Highland barley (HB) boasts a comprehensive and unique nutritional composition, characterized by high protein, high fiber, high vitamins, low fat, low sugar, and diverse bioactive components. These attributes make it a promising candidate for alleviating high blood sugar. This review explores the mechanisms underlying the glucose-lowering properties of HB, emphasizing its nutritional profile and bioactive constituents. Additionally, it examines the impact of common HB processing techniques on its nutrient composition and highlights its applications in food products. By advancing the understanding of HB's value and mechanisms in diabetes prevention, this review aims to facilitate the development of HB-based foods suitable for diabetic patients.

Highland Barley β-Glucan Relieves Symptoms of Colitis via PPARα-Mediated Intestinal Stem Cell Proliferation

Intestinal stem cells (ISCs) are necessary to maintain intestinal renewal. Here, we found that the highland barley β-glucan (HBG) alleviated pathological symptoms and promoted the proliferation of intestinal stem cells in colitis mice. Notably, metabolomics studies showed that docosahexaenoic acid (DHA) was significantly increased by the HBG treatment. DHA is a ligand for peroxisome proliferator-activated receptor α (PPARα), which can promote ISC proliferation. Expectedly, HBG facilitated the expression of intestinal PPARα and the proliferation of ISCs in colitis mice. Further experiments verified that DHA significantly facilitated the expression of PPARα and the proliferation of ISCs in intestinal organoids. Intriguingly, the effect of DHA on ISC proliferation was reversed by the PPARα inhibitor. Together, our data indicate that HBG might accelerate PPARα-mediated ISC proliferation through DHA. This provides new insights into the effective application of polysaccharides in maintaining intestinal homeostasis.

Effect of GABA combined with ultrasound stress germination treatment on phenolic content and antioxidant activity of highland barley

BACKGROUND

This study investigated the effects of γ-aminobutyric acid (GABA) combined with ultrasonic stress germination (AUG) treatment on the phenolic content and antioxidant activity of highland barley (HB). Key variables, including germination times (ranging from 0 to 96 h), ultrasonic power (200-500 W), and GABA concentration (5-20 mmol/L), were optimized using response surface methodology (RSM) to enhance the enrichment of phenolic compounds. Furthermore, the study assessed the content, composition, and antioxidant activities of phenolic compounds in HB under various treatment conditions such as germination alone (G), ultrasonic stress germination (UG), and AUG treatment.

RESULTS

The study identified optimal conditions for the phenolic enrichment of HB, which included a germination time of 60 h, an ultrasound power of 300 W, and a GABA concentration of 15 mmol L-1. Under these conditions, the total phenolic content (TPC) in HB was measured at 7.73 milligrams of gallic acid equivalents per gram dry weight (mg GAE/g DW), representing a 34.96% enhancement compared to untreated HB. Notably, all treatment modalities - G, UG, and AUG - significantly increased the phenolic content and antioxidant activity in HB, with the AUG treatment proving to be the most effective.

CONCLUSION

These obtained results suggest that AUG treatment is a promising processing method for enriching phenolic compounds and improving antioxidant activity in HB. Subsequently, the AUG-treated HB can be used to develop phenolic-rich germinated functional foods to further broaden the application of HB. © 2024 Society of Chemical Industry.

Role of total polyphenol content in seed germination characteristics of spring barley varieties amidst climate change

The amount of total polyphenol content (TPC) in the grain could provide insights into the conditions during maturation and might also serve as an indicator of the grain's ability to germinate in the malting process or as seeds in the field. Varieties with higher natural TPC content might exhibit better germination parameters both in the field and in the malt house. This study investigates the relationship between TPC and seed germination characteristics i.e. seed vigour in four spring barley varieties over two years, considering diverse environmental conditions and exposure to drought conditions. The evaluation of seed germination characteristics in barley, with a focus on the root length and average diameter under drought conditions (-0.5 MPa) and suboptimal temperature (10 °C), was conducted. Drought conditions were induced using polyethylene glycol (PEG 6000). After durations of seven and fourteen days, the germinated seeds from the Petri dishes were scanned and subjected to analysis using WinRHIZO software following the metrics: Len 7, Len 14 (root length after seven and fourteen days in cm) and AvgD 7, AvgD 14 (root diameter after seven and fourteen days in mm). The findings support our initial hypothesis, indicating a variety-specific relationship between seed germination characteristics and increased TPC, where higher germination parameters might be associated with elevated TPC levels in some barley varieties.

Dietary polyphenols regulate appetite mechanism via gut-brain axis and gut homeostasis

Nowadays, due to the rise of fast-food consumption, the metabolic diseases are increasing as a result of high-sugar and high-fat diets. Therefore, there is an urgent need for natural, healthy and side-effect-free diets in daily life. Whole grain supplementation can enhance satiety and regulate energy metabolism, effects that have been attributed to polyphenol content. Dietary polyphenols interact with gut microbiota to produce intermediate metabolites that can regulate appetite while also enhancing prebiotic effects. This review considers how interactions between gut metabolites and dietary polyphenols might regulate appetite by acting on the gut-brain axis. In addition, further advances in the study of dietary polyphenols and gut microbial metabolites on energy metabolism and gut homeostasis are summarized. This review contributes to a better understanding of how dietary polyphenols regulate appetite via the gut-brain axis, thereby providing nutritional references for citizens' dietary preferences.

Physiological Mechanisms by Which the Functional Ingredients in Beer Impact Human Health

Nutritional therapy, for example through beer, is the best solution to human chronic diseases. In this article, we demonstrate the physiological mechanisms of the functional ingredients in beer with health-promoting effects, based on the PubMed, Google, CNKI, and ISI Web of Science databases, published from 1997 to 2024. Beer, a complex of barley malt and hops, is rich in functional ingredients. The health effects of beer against 26 chronic diseases are highly similar to those of barley due to the physiological mechanisms of polyphenols (phenolic acids, flavonoids), melatonin, minerals, bitter acids, vitamins, and peptides. Functional beer with low purine and high active ingredients made from pure barley malt, as well as an additional functional food, represents an important development direction, specifically, ginger beer, ginseng beer, and coix-lily beer, as consumed by our ancestors ca. 9000 years ago. Low-purine beer can be produced via enzymatic and biological degradation and adsorption of purines, as well as dandelion addition. Therefore, this review paper not only reveals the physiological mechanisms of beer in overcoming chronic human diseases, but also provides a scientific basis for the development of functional beer with health-promoting effects.

Ultrafine grinding improves the nutritional, physicochemical, and antioxidant activities of two varieties of whole-grain highland barley

Effects of ultrafine grinding on the nutritional profile, physicochemical properties, and antioxidant activities of whole-grain highland barley (HB) including white highland barley (WHB) and black highland barley (BHB) were studied. Whole-grain HB was regularly ground and sieved through 80 mesh get 80 M powder, and HB was ultrafine grounded and sieved through 80 mesh, 150 mesh, and 200 mesh get 80UMM, 150UMM, and 200UMM samples. Particle size of WHB and BHB reduced significantly after ultrafine grinding. As the particle size decreased, moisture content of WHB and BHB decreased significantly, whereas fat content increased significantly. Redistribution of fiber components in WHB and BHB from insoluble to soluble fractions was also observed. Wherein, content of soluble pentosan of WHB and BHB increased significantly from 0.56% and 0.78% (80 M) to 0.91% and 1.14% (200UMM), respectively. Damaged starch of WHB and BHB increased significantly from 8.16% and 8.21% (80 M) to 10.29% and 10.07% (200UMM), respectively. Content of phenolic acid and flavonoid of WHB and BHB and associated antioxidant capacity were increased after ultrafine grinding. Color of L* value increased significantly, a* and b* values decreased significantly, indicating the whiteness of WHB and BHB was increased after ultrafine grinding. Pasting temperature of WHB and BHB decreased, whereas peak viscosity increased. X-ray diffraction patterns of HB showed typical A- and V-style polymorphs and the relative crystallinity of HB decreased as the particle size decreased. Taken together, ultrafine grinding has shown great potential in improving the nutritional, physiochemical, and antioxidant properties of whole-grain HB. Our research findings could help better understand the ultrafine grinded whole grain HB in food industry.

Determination of free and bound antioxidants in Kamut® wheat by HPLC with triple detector (DAD-CAD-MS)

Kamut® wheat (Triticum turgidum ssp. turanicum), an ancient, underutilized cereal, offers potential health benefits due to its phenolic compounds. This study aimed to investigate the antioxidant potential of Kamut® wheat's free and bound phenolic extracts using an HPLC system equipped with three detectors. The bound extracts, released after alkaline hydrolysis, exhibited higher total phenolic and flavonoid content compared to the free extracts (p < 0.05). The total antioxidant capacity of bound extracts was six-fold greater than in free extracts (p < 0.05). The main antioxidants in free extracts were tyrosine, phenylalanine, tryptophan, and apigenin. In bound extracts, ferulic acid, its dimers and trimer were present. Kamut® wheat exhibited a source of dietary antioxidants and should be considered a potential ingredient for the development of functional foods. Also, the HPLC-triple detector system is effective for in-depth profiling of antioxidant compounds, paving the way for future research on similar grains.

Metabolomics Characterization of Phenolic Compounds in Colored Quinoa and Their Relationship with In Vitro Antioxidant and Hypoglycemic Activities

Chenopodium quinoa Willd. is rich in phenolic compounds and exhibits diverse biological activities. Few studies have focused on the effect of colored quinoa's phenolic profile on potential biological activity. This study used a UPLC-MS/MS-based metabolomic approach to examine the quinoa phenolics and their association with in vitro antioxidant and hypoglycemic properties. In total, 430 polyphenols, mainly phenolic acids, flavonoids, and flavonols, were identified. Additionally, 121, 116, and 148 differential polyphenols were found between the white and black, white and red, and black and red comparison groups, respectively; 67 polyphenols were screened as shared key differential metabolites. Phenylalanine, tyrosine, and the biosynthesis of plant secondary metabolites were the main differently regulated pathways. Black quinoa had better total phenolic contents (643.68 mg/100 g DW) and antioxidant capacity, while white quinoa had better total flavonoid contents (90.95 mg/100 g DW) and in vitro α-amylase (IC50 value of 3.97 mg/mL) and α-glucosidase (IC50 value of 1.08 mg/mL) inhibition activities. Thirty-six polyphenols, including epicatechin and linarin, etc., were highly correlated with in vitro antioxidant activity, while six polyphenols, including tiliroside and chrysoeriol, etc., were highly correlated with in vitro hypoglycemic activity. This study may provide important information for colored quinoa resources to develop their healthy food applications.

An investigation into the effects of various processing methods on the characteristic compounds of highland barley using a widely targeted metabolomics approach

This study explored the influence of diverse processing methods (cooking (CO), extrusion puffing (EX), and steam explosion puffing (SE), stir-frying (SF) and fermentation (FE)) on highland barley (Qingke) chemical composition using UHPLC-MS/MS based widely targeted metabolomics. Overall, 827 metabolites were identified and categorized into 16 classes, encompassing secondary metabolites, amino acids, nucleotides, lipids, etc. There 43, 85, 131, 51 and 98 differential metabolites were respectively selected from five comparative groups (raw materials (RM) vs CO/EX/SE/SF/FE), mainly involved in amino acids, nucleotides, flavonoids, and alkaloids. Compared to other treated groups, FE group possessed the higher content of crude protein (15.12 g/100 g DW), and the relative levels of free amino acids (1.32 %), key polyphenols and arachidonic acid (0.01 %). EX group had the higher content of anthocyanins (4.22 mg/100 g DW), and the relative levels of free amino acids (2.02 %) and key polyphenols. SE group showed the higher relative levels of phenolic acids (0.14 %), flavonoids (0.20 %) and alkaloids (1.17 %), but the lowest free amino acids (0.75 %). Different processing methods all decreased Qingke's antioxidant capacity, with the iron reduction capacity (988.93 μmol/100 g DW) in SE group was the lowest. On the whole, FE and EX were alleged in improving Qingke's nutritional value. CO and SF were also suitable for Qingke processing since fewer differential metabolites were identified in CO vs RM and SF vs RM groups. Differential metabolites were connected to 14 metabolic pathways, with alanine, aspartate, and glutamate metabolism being central. This study contributed theoretical groundwork for the scientific processing and quality control of Qingke products.

A comparative metabolomics study of polyphenols in highland barley (Hordeum vulgare L.) grains with different colors

Highland barley (HB) grains are gaining increasing popularity owing to their high nutritional merits. However, only limited information is available on the metabolic profiles of HB grains polyphenols, especially the difference of polyphenols in different colors of HB. In this study, we determined the metabolic profiles of black, blue, and white HB grains via an ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS)-based metabolomics. A total of 402 metabolites were identified, among which 198, 62, and 189 metabolites displayed different accumulation patterns in the three comparison groups (WHB vs. BKHB, WHB vs. BEHB, BEHB vs. BKHB), respectively. In particular, flavonoids and phenolic acids contents displayed considerable differences among the three HB cultivars. The phenolics content of black HB was relatively high. Additionally, "Flavonoid biosynthesis" and "flavone and flavonol biosynthesis" were the significantly enriched pathways. In conclusion, this study provides comprehensive insights into the adequate utilization and development of novel HB-based functional foods.

Response of salt stress resistance in highland barley (Hordeum vulgare L. var. nudum) through phenylpropane metabolic pathway

Highland barley (Hordeum vulgare L. var. nudum) is a grain crop that grows on the plateau under poor and high salt conditions. Therefore, to cultivate high-quality highland barley varieties, it is necessary to study the molecular mechanism of strong resistance in highland barley, which has not been clearly explained. In this study, a high concentration of NaCl (240 mmol/L), simulating the unfavorable environment, was used to spray the treated highland barley seeds. Transcriptomic analysis revealed that the expression of more than 8,000 genes in highland barley seed cells was significantly altered, suggesting that the metabolic landscape of the cells was deeply changed under salt stress. Through the KEGG analysis, the phenylpropane metabolic pathway was significantly up-regulated under salt stress, resulting in the accumulation of polyphenols, flavonoids, and lignin, the metabolites for improving the stress resistance of highland barley seed cells, being increased 2.71, 1.22, and 1.17 times, respectively. This study discovered that the phenylpropane metabolic pathway was a significant step forward in understanding the stress resistance of highland barley, and provided new insights into the roles of molecular mechanisms in plant defense.

Phytochemical Screening on Phenolic, Flavonoid Contents, and Antioxidant Activities of Six Indigenous Plants Used in Traditional Thai Medicine

The antioxidant activity of a traditional Thai formula has been studied and compared to each plant. The formula comprised the roots of Caesalpinia digyna Rottler, Huberantha cerasoides (Roxb.) Benth), Oxyceros horridus Lour, Antidesma ghaesembilla Gaerth, Combretum quadrangulare Kurz, and Ziziphus cambodiana Pierre. The stem was also studied in comparison. The ethanolic extract from each plant part and the mixed plants mimicking the traditional formula were prepared and investigated for antioxidant capability in vitro via DPPH radical scavenging and ferric-reducing antioxidant power assays. The phytochemical constituents were determined by chemical screening, total phenolic (TPC) and flavonoid contents (TFC), and high-performance liquid chromatography. The relationship between antioxidant activity and the contributed phytochemicals was determined using correlation analysis and principal component analysis (PCA). Results showed that extracts from both parts of the plant formula showed the highest antioxidant activity compared to a single plant extract. Among the six plants, C. digyna exhibited the highest TPC and antioxidant activity. TPC had a strong positive correlation with antioxidant activity. PCA revealed that gallic acid contributed to the antioxidant activity. In conclusion, the ethanolic extracts of the traditional formula and C. digyna have the potential for further chemical characterization and study related to antioxidant activity.

Prebiotic and Anti-Adipogenic Effects of Radish Green Polysaccharide

Radish (Raphanus sativus L.) greens are consumed as a source of nutrition, and their polysaccharides such as rhamnogalacturonan-I possess certain beneficial properties. This study investigated the prebiotic effects of a radish green polysaccharide (RGP) on gut health and obesity. The prebiotic activity of RGP was evaluated based on the pH changes and short-chain fatty acids (SCFAs) concentration. The results showed that 0.5% RGP had a higher prebiotic activity score than inulin and increased SCFAs production in all five prebiotic strains. Moreover, RGP inhibited fat accumulation in 3T3-L1 adipocytes, indicating its potential to reduce obesity. Overall, these findings suggested that the polysaccharide of radish greens has prebiotic effects and may serve as a beneficial prebiotic for gut health and obesity.

Profile of phenolic compounds and antioxidant activity of organically and conventionally grown black-grain barley genotypes treated with biostimulant

Beneficial dietary and pro-health values, have resulted in the increasing consumption importance of barley. Therefore, genotypes and cultivation methods are sought that guarantee high functional value of grain. The aim of the study was to assess the content of phenolic acids, flavonoids, chlorophylls, anthocyanidins, phytomelanin and antioxidant activity of grain of three barley genotypes depending on agricultural technology. Two of them are primary genotypes with dark grain pigmentation Hordeum vulgare L. var nigricans and H. vulgare L. var. rimpaui, the third is a modern cultivar 'Soldo' H. vulgare with yellow grain, which is the control sample. Evaluated the effect of foliar application of a amino-acids biostimulant on the functional properties of grain under the conditions of organically and conventionally cultivations. The results indicated a higher antioxidant activity and the concentration of phenolic acids, flavonoids and phytomelanin in the black-grain genotypes. Organic cultivation and application of amino acids had increased the content of phenolic compounds in grain. The antioxidant activity was correlated with the content of syringic acid, naringenin, quercetin, luteolin and phytomelanin. Organically cultivation and the foliar application of an amino acid biostimulant improved the functional properties of barley grain, in particular the original, black-grained genotypes.

Comparison between Ultrasound- and Microwave-Assisted Extraction Methods to Determine Phenolic Compounds in Barley (Hordeum vulgare L.)

Barley (Hordeum vulgare L.) is one of the major cereal crops worldwide. It is grown not only to be used as fodder but also for human consumption. Barley grains are a great source of phenolic compounds, which are particularly interesting for their health-promoting antioxidant properties, among other benefits. Two extraction methods, namely ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE), have been optimized and compared by using Box-Behnken design (BBD) to determine both the antioxidant power and the phenolic compound levels of the extracts. Three variables have been assessed based on these designs: solvent composition (% MeOH in water), temperature (°C), and sample-to-solvent ratio (mg sample mL^-1 solvent). The solvent composition used and the interaction between the solvent and the temperature were the most significant variables in terms of recovery of phenolic compounds and antioxidant capacity of the extracts. Short extraction times, a high precision level, and good recoveries have been confirmed for both methods. Moreover, they were successfully applied to several samples. Significant differences regarding the level of phenolic compounds and antioxidant power were revealed when analyzing three different barley varieties. Specifically, the amounts of phenolic compounds ranged from 1.08 to 1.81 mg gallic acid equivalent g^-1 barley, while their antioxidant capacity ranged from 1.35 to 2.06 mg Trolox equivalent g^-1 barley, depending on the barley variety. Finally, MAE was found to be slightly more efficient than UAE, presenting higher levels of phenolic compounds in the extracts.

Phytochemical profiling, anti-hyperglycemic, antifungal, and radicals scavenging potential of crude extracts of Athyrium asplenioides- an in-vitro approach

This research was aimed to evaluate the phytochemical profile, antifungal, anti-hyperglycemic, as well as antioxidant activity competence of different extracts of Athyrium asplenioides through in-vitro approach. The A. asplenioides crude methanol extract contained considerable quantity of pharmaceutically precious phytochemicals (saponins, tannins, quinones, flavonoid, phenols, steroid, and terpenoids) than others (acetone, ethyl acetate, and chloroform). Interestingly, the crude methanol extract showed remarkable antifungal activity against Candida species (C. krusei: 19.3 ± 2 mm > C. tropicalis: 18.4 ± 1 mm > C. albicans: 16.5 ± 1 mm > C. parapsilosis: 15.5 ± 2 mm  >  C. glabrate: 13.5 ± 2 mm > C. auris: 7.6 ± 1 mm) at a concentration of 20 mg mL-1. The crude methanol extract also showed remarkable anti-hyperglycemic activity on concentration basis. Surprisingly, remarkable free radicals scavenging potential against DPPH (76.38%) and ABTS (76.28%) free radicals at a concentration of 20 mg mL-1. According to the findings, the A. asplenioides crude methanol extract contains pharmaceutically valuable phytochemicals and may be useful for drug discovery.

Dry heating affects the multi-structures, physicochemical properties, and in vitro digestibility of blue highland barley starch

As a physical method for starch modification, dry heating treatment (DHT) at high temperatures (150 and 180°C, respectively) was applied to blue highland barley (BH) starch with different durations (2 and 4 h). The effects on its multi-structures, physicochemical properties, and in vitro digestibility were investigated. The results showed that DHT had changed the morphology of BH starch, and the diffraction pattern remained an "A"-type crystalline structure. However, with an extension of DHT temperature and time, the amylose content, gelatinization temperature, enthalpy value, swelling power, and pasting viscosity of modified starches decreased, while the light transmittance, solubility, and water and oil absorption capacities increased. Additionally, compared with native starch, the content of rapidly digestible starch in modified samples increased after DHT, whereas those of slowly digestible starch and RS decreased. Based on these results, the conclusion could be drawn that DHT is an effective and green way to transform multi-structures, physicochemical properties, and in vitro digestibility of BH starch. This fundamental information might be meaningful to enrich the theoretical basis of physical modification on BH starch and extend the applications of BH in the food industry.

Enhancement of Polyphenols and Antioxidant Activity in Germinated Black Highland Barley by Ultrasonication

The aim of this study was to investigate the effect of ultrasonic stress germination (USG) on total phenolic contents (TPC), total flavonoid contents (TFC), the phenolic compositions, and antioxidant activities of black highland barley (BHB). The USG processing parameters, polyphenol profile, phenolic compositions, and antioxidant activities were explored after USG. Results showed that the optimal USG parameters were as follows: 350 W ultrasonic pretreatment power, 30 °C ultrasonication temperature, 25 min ultrasonication time, and 64 h germination time. Under these conditions, the total phenolic content (688.84 ± 5.30 mg/100 g) and total flavonoid content (59.23 ± 0.45 mg/100 g) of BHB were increased by 28.55% and 10.15%, respectively, compared to the untreated samples. In addition, the USG treatment could more effectively enrich bound phenolic acids and free flavonoids, among which the content of catechin was significantly increased by USG and was the main characteristic substance. Moreover, the USG treatment could improve the antioxidant activity and had a higher antioxidant potency composite index (APC index) (97.91%) of BHB. These results indicate that USG might be an effective method to enrich polyphenols and improve antioxidant activity in BHB.

An Overview of Bioactive Phenolic Molecules and Antioxidant Properties of Beer: Emerging Trends

Beer is one of the oldest and most common beverages worldwide. The phenolic contents and antioxidant properties of beer are crucial factors in evaluating its nutritional quality. Special beers brewed with the addition of adjuncts are gaining in consumer preference, in response to demands for healthy food and new gustatory and olfactory stimuli. Many studies recently dealt with functional beers brewed with the addition of adjuncts. This review focuses on bioactive molecules, particularly the composition of phenolic compounds, and the antioxidant activity of beer. The current knowledge concerning the effect of the addition of adjuncts in the form of fruit, vegetables, herbs, and natural foods on the polyphenol content, antioxidant properties, and phenolic profile of beer is reviewed, with an outline of the emerging trends in brewing processes. Future studies need to complete the identification and characterization of the bioactive molecules in beer, as well as studying their absorption and metabolic fate in humans.

Dietary Dried Jujube Fruit Powder (DJFP) Supplementation Improves Growth Performance, Antioxidant Stability, and Meat Composition in Broilers

Nowadays, broiler production is faced with great challenges due to intensive culture modes, and chickens are more susceptible to oxidative stress. Consequently, synthetic antioxidants have been used to reduce this process, but their use has shown potential health risks. Thus, the use of natural ingredients has been suggested as a strategy to prevent oxidative stress. This study investigated how dietary dried jujube fruit powder (DJFP) supplementation influences the growth performance, antioxidant stability, meat composition, and nutritional quality of Cobb broilers. A total of 360 unsexed broilers (1-day-old) were randomly assigned to treatments that varied in DJFP levels: a basal diet without DJFP (control) and diets supplemented with 50 g/kg DJFP (P1), 100 g/kg DJFP (P2), and 150 g/kg DJFP (P3), with 9 replicates per treatment (90 broilers/treatment or 10 broilers/replicate). The results demonstrated improvement in the growth performance of broilers in terms of body weight (BW), body weight gain (WG), average daily body weight gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR) following dietary DJFP supplementation. In addition, the antioxidant stabilities in the DJFP-treated broilers were improved and inhibited the production of lipid oxidation products compared with the control, with those in the P2 group showing the most marked effect. Moreover, dietary DJFP supplementation significantly increased (p < 0.05) the activity of antioxidant enzymes in broilers. Furthermore, the breast meat of the broilers displayed an increased protein content with a simultaneous reduction in the fat content after DJFP treatment (p < 0.05). Essential amino acid levels were higher in the DJFP-supplemented groups (p < 0.05). The sum of saturated fatty acids was lower, and that of monounsaturated fatty acids (MUFAs) and the polyunsaturated fatty acid/saturated fatty acid ratio (PUFA/SFA) were higher in the DJFP-supplemented groups (p < 0.05). Together, these results indicate that up to 100 g/kg of dietary DJFP supplementation can enhance the growth performance and antioxidant capacity, meat composition, and amino acid and fatty acid composition in broiler breast meat. In conclusion, dietary DJFP supplementation is a healthy alternative to the use of synthetic antioxidants in broiler production, especially in regions rich in jujube resources.

Recent Developments in Polyphenol Applications on Human Health: A Review with Current Knowledge

Polyphenol has been used in treatment for some health disorders due to their diverse health promoting properties. These compounds can reduce the impacts of oxidation on the human body, prevent the organs and cell structure against deterioration and protect their functional integrity. The health promoting abilities are attributed to their high bioactivity imparting them high antioxidative, antihypertensive, immunomodulatory, antimicrobial, and antiviral activity, as well as anticancer properties. The application of polyphenols such as flavonoids, catechin, tannins, and phenolic acids in the food industry as bio-preservative substances for foods and beverages can exert a superb activity on the inhibition of oxidative stress via different types of mechanisms. In this review, the detailed classification of polyphenolic compunds and their important bioactivity with special focus on human health are addressed. Additionally, their ability to inhibit SARS-CoV-2 could be used as alternative therapy to treat COVID patients. Inclusions of polyphenolic compounds in various foods have demonstrated their ability to extend shelf life and they positive impacts on human health (antioxidative, antihypertensive, immunomodulatory, antimicrobial, anticancer). Additionally, their ability to inhibit the SARS-CoV-2 virus has been reported. Considering their natural occurrence and GRAS status they are highly recommended in food.

Polyphenol Profile and In Vitro Antioxidant and Enzyme Inhibitory Activities of Different Solvent Extracts of Highland Barley Bran

Five different solvent extracts of highland barley bran were analyzed and compared for their polyphenol profile, antioxidant activity, and α-glucosidase and α-amylase inhibitory activities. The highland barley bran acetone extract had the highest total phenolic content, total flavonoid content, and antioxidant capacity. It was followed by the methanol and ethanol extracts, while n-butanol and ethyl acetate extracts exhibited lower measured values. Diosmetin, luteolin, protocatechuic acid, vanillic acid, ferulic acid, phlorogucinol, diosmin, isoquercitrin, catechin, and isovitexin were among the most abundant phenolic compounds identified in different solvent extracts, and their concentrations varied according to the solvent used. The highest α-glucosidase and α-amylase inhibitory activity were observed in the ethyl acetate extract of highland barley bran, followed by the acetone and methanol extracts. In contrast, n-butanol and ethanol extracts exhibited lower measured values. The different solvent extracts were effective inhibitors for α-glucosidase and α-amylase with activity reaching to 34.45-94.32% and 22.08-35.92% of that of positive control acarbose, respectively. There were obvious correlations between the phenolic content and composition of different solvent extracts and their in vitro antioxidant activity, α-glucosidase inhibition activity and α-amylase inhibition activity. Black barley bran is an excellent natural raw material for developing polyphenol-rich functional foods and shows good antioxidant and hypoglycemic potential to benefit human health.

Effect of pearling on nutritional value of highland barley flour and processing characteristics of noodles

Highland barley is increasingly recognized as its nutritional benefits but its structure restricts the development and utilization in the food industry. The quality of highland barley products may be impacted by pearling, an essential step before the hull bran is consumed or further processed. The nutrition, function and edible qualities of three highland barley flour (HBF) with different pearling rates were assessed in this study. The content of resistant starch was the highest when the pearling rate of QB27 and BHB was 4%, while 8% of QB13. Un-pearled HBF showed higher DPPH, ABTS and superoxide radicals inhibition rates. The break rates of QB13, QB27 and BHB obviously decreased from 51.7%, 53.3% and 38.3% to 35.0%, 15.0% and 6.7% respectively at 12% pearling rate. PLS-DA model further attributed the improvement of pearling on noodles quality to the alteration of resilience, hardness, tension distance, breaking rate and water absorption of noodles.

Impacts of Proanthocyanidin Binding on Conformational and Functional Properties of Decolorized Highland Barley Protein

The impacts of interaction between proanthocyanidin (PC) and decolorized highland barley protein (DHBP) at pH 7 and 9 on the functional and conformational changes in DHBP were investigated. It was shown that PC strongly quenched the intrinsic fluorescence of DHBP primarily through static quenching. PC and DHBP were mainly bound by hydrophobic interactions. Additionally, free sulfhydryl groups and surface hydrophobicity obviously decreased in DHBP after combining with PC. The zeta potential of DHBP-PC complexes at pH 7 increased significantly. A change in the structure of DHBP was caused by interactions with PC, resulting in an increase in the number of β-sheets, a decrease in the number of α-helixes, and a spectral shift in the amide Ⅱ band. Furthermore, the presence of PC enhanced the foaming properties and antioxidant activity of DHBP. Overall, this study suggests that DHBP-PC complexes at pH 7 could be designed as a stable additive, and illustrates the potential applications of DHBP-PC complexes in the food industry.

Importance of Insoluble-Bound Phenolics to the Antioxidant Potential Is Dictated by Source Material

Insoluble-bound phenolics (IBPs) are extensively found in the cell wall and distributed in various tissues/organs of plants, mainly cereals, legumes, and pulses. In particular, IBPs are mainly distributed in the protective tissues, such as seed coat, pericarp, and hull, and are also available in nutritional tissues, including germ, epicotyl, hypocotyl radicle, and endosperm, among others. IBPs account for 20-60% of the total phenolics in food matrices and can exceed 70% in leaves, flowers, peels, pulps, seeds, and other counterparts of fruits and vegetables, and up to 99% in cereal brans. These phenolics are mostly covalently bound to various macromolecules such as hemicellulose, cellulose, structural protein, arabinoxylan, and pectin, which can be extracted by acid, alkali, or enzymatic hydrolysis along with various thermal and non-thermal treatments. IBPs obtained from various sources exhibited a wide range of biological activities, including antioxidant, anti-inflammatory, antihypertensive, anticancer, anti-obesity, and anti-diabetic properties. In this contribution, the chemistry, distribution, biological activities, metabolism, and extraction methods of IBPs, and how they are affected by various treatments, are summarized. In particular, the effect of thermal and non-thermal processing on the release of IBPs and their antioxidant potential is discussed.

Highland Barley Tea Polyphenols Extract Alleviates Skeletal Muscle Fibrosis in Mice by Reducing Oxidative Stress, Inflammation, and Cell Senescence

The tea of roasted Highland barley is a cereal-based drink rich in polyphenols. A model of skeletal muscle senescence and fibrosis was constructed using d-galactose-induced C2C12 myotubes, and Highland barley tea Polyphenols (HBP) were extracted for the intervention. We found that HBP effectively alleviated oxidative stress, inflammation, and fibrosis induced by d-galactose-induced skeletal muscle senescence. Also, HBP treatment significantly down-regulated pro-fibrotic genes, inflammation, and oxidative stress levels in a contusion model of senescent mice. Reduced levels of SIRT3 protein was found to be an essential factor in skeletal muscle senescence and fibrosis in both cellular and animal models, while HBP treatment significantly increased SIRT3 protein levels and viability in skeletal muscle. The ability of HBP to mitigate skeletal muscle fibrosis and oxidative stress was significantly reduced after SIRT3 silencing. Together, these results suggest that HBP intervention can significantly alleviate aging-induced oxidative stress, inflammation, and skeletal muscle fibrosis, with the activation of SIRT3 as the underlying mechanism of action.

Analyses of Fatty Acids, Proteins, Ascorbic Acid, Bioactive Phenolic Compounds and Antioxidant Activity of Canadian Barley Cultivars and Elite Germplasm

Barley (Hordeum vulgare L.) grain is rich in fiber and antioxidant phytochemicals, including fatty acids, proteins, phenolic compounds, vitamins, and minerals, that offer various health benefits. Research on identifying different barley genotypes based on their health attributes is very limited. In this study, we performed an analysis of fatty acids, proteins, ascorbic acid, phenolic compounds, and antioxidant activity of several Canadian barley cultivars and elite breeding lines. Linoleic acid (C18:2) was the predominant fatty acid present in the tested barley cultivars. The cultivar CDC Bold contained the highest amount of ascorbic acid, while the highest protein content was in CDC Mindon. An assessment of the free and bound phenolic compounds of barley grains showed quantitative changes among different genotypes of Canadian barley. Catechin is the most abundant molecule in free phenolics, while ferulic acid and para-coumeric acid are the most abundant in bound phenolics. Ferulic acid and vanillic acid were molecules detected in the soluble free fraction of all genotypes. Para-coumeric acid was detected only in genotypes such as CDC Copeland, CDC Bold, Lowe, and elite breeding Line 5 of both free and bound fractions of barley. Breeding Line 5 had the lowest antioxidant activity. An analysis of the above molecules and parameters of Canadian barley would help to uncover potential biomarkers in order to distinguish individual barley genotypes.

The Influence of Different Pretreatment Methods of Highland Barley by Solid-State Fermentation with Agaricus sinodeliciosus var. Chaidam ZJU-TP-08 on Its Nutrient Content, Functional Properties and Physicochemical Characteristics

To enhance the nutritional value of highland barley (HB), this work investigated the effects of solid-state fermentation (SSF) by Agaricus sinodeliciosus var. Chaidam ZJU-TP-08 on nutrient content, phenolic components, antioxidant activities, and physicochemical characteristics of HB upon different pretreatments (germination, ultrasound and soaking). The results showed that germinated highland barley (GHB) exhibited higher levels of ergosterol (0.19 ± 0.01 mg/g) in all fermentation groups. The content of β-glucan was higher in the SSF-GHB, with an increase of 24.21% compared to the control. The content of total amino acids, dietary fiber, total phenols and flavonoids were higher in the fermentation HB pretreated by ultrasound, increasing respectively by 5.60%, 61.50%, 25.10% and 65.32% compared to the control group. In addition, the colonized HB exhibited excellent physicochemical characteristics, including increased water solubility index and decreased pasting characteristics. Herein, the nutritional value and the biological activities were enriched in the pretreated HB through SSF, indicating its potential application for nutrition-enriched functional foods.

Formation and metabolism of 6-(1-acetol)-8-(1-acetol)-rutin in foods and in vivo, and their cytotoxicity

Methylglyoxal (MGO) is a highly reactive precursor which forms advanced glycation end-products (AGEs) in vivo, which lead to metabolic syndrome and chronic diseases. It is also a precursor of various carcinogens, including acrylamide and methylimidazole, in thermally processed foods. Rutin could efficiently scavenge MGO by the formation of various adducts. However, the metabolism and safety concerns of the derived adducts were paid less attention to. In this study, the optical isomers of di-MGO adducts of rutin, namely 6-(1-acetol)-8-(1-acetol)-rutin, were identified in foods and in vivo. After oral administration of rutin (100 mg/kg BW), these compounds reached the maximum level of 15.80 μg/L in plasma at 15 min, and decreased sharply under the quantitative level in 30 min. They were detected only in trace levels in kidney and fecal samples, while their corresponding oxidized adducts with dione structures presented as the predominant adducts in kidney, heart, and brain tissues, as well as in urine and feces. These results indicated that the unoxidized rutin-MGO adducts formed immediately after rutin ingestion might easily underwent oxidation, and finally deposited in tissues and excreted from the body in the oxidized forms. The formation of 6-(1-acetol)-8-(1-acetol)-rutin significantly mitigated the cytotoxicity of MGO against human gastric epithelial (GES-1), human colon carcinoma (Caco-2), and human umbilical vein endothelial (HUVEC) cells, which indicated that rutin has the potential to be applied as a safe and effective MGO scavenger and detoxifier, and AGEs inhibitor.

Polyphenols in Highland barley tea inhibit the production of Advanced glycosylation end-products and alleviate the skeletal muscle damage

SCOPE

Highland barley tea is a kind of caffeine-free cereal tea. Previous studies have shown that it was rich in polyphenol flavonoids. Here, the effect of Highland barley tea polyphenols (HBP) on the production of advanced glycosylation end-products and alleviate the skeletal muscle damage is systematically investigated.

METHODS

and results: HBP effectively inhibited the formation of AGEs in vitro, and 12 phenolic compounds were identified. In addition, D-galactose was used to construct a mouse senescence model and intervened with different doses of HBP. It was found that high doses of HBP effectively inhibited AGEs in serum and flounder muscle species and increased muscle mass in flounder muscle; also, high doses of HBP increased the expression of the mitochondrial functional protein SIRT3 and decreased the expression of myasthenia-related proteins. Furthermore, cellular experiments showed that AGEs could significantly increase oxidative stress in skeletal muscle.

CONCLUSION

These data indicate that the relationship between the biological activity and HBP properties is relevant since Highland barley could be a potential functional food to prevent AGEs-mediated skeletal muscle damage. This article is protected by copyright. All rights reserved.

Recent Developments in Fermented Cereals on Nutritional Constituents and Potential Health Benefits

Fermentation is one of the most economical and safe methods to improve the nutritional value, sensory quality and functional characteristics of raw materials, and it is also an important method for cereal processing. This paper reviews the effects of microbial fermentation on cereals, focusing on their nutritional value and health benefits, including the effects of fermentation on the protein, starch, phenolic compounds contents, and other nutrient components of cereals. The bioactive compounds produced by fermented cereals have positive effects on health regulation. Finally, the future market development of fermented cereal products is summarized and prospected.

Evaluation of Nutritional Components, Phenolic Composition, and Antioxidant Capacity of Highland Barley with Different Grain Colors on the Qinghai Tibet Plateau

The nutritional composition, polyphenol and anthocyanin composition, and antioxidant capacity of 52 colored highland barley were evaluated. The results showed that the protein content of highland barley in the black group was the highest, the total starch and fat contents in the blue group were the highest, the amylose content in the purple group was quite high, the fiber content in the yellow group was quite high, and the β-glucan content of the dark highland barley (purple, blue and black) was quite high. The polyphenol content and its antioxidant capacity in the black group were the highest, while the anthocyanin content and its antioxidant capacity in the purple highland barley were the highest. Ten types of monomeric phenolic substances were the main contributors to DPPH, ABTS, and FRAP antioxidant capacity. All varieties could be divided into four categories according to nutrition or function. The grain color could not be used as an absolute index to evaluate the quality of highland barley, and the important influence of variety on the quality of highland barley also needed to be considered. In actual production, suitable raw materials must be selected according to the processing purpose and variety characteristics of highland barley.

In Vitro and In Vivo Digestive Fate and Antioxidant Activities of Polyphenols from Hulless Barley: Impact of Various Thermal Processing Methods and β-Glucan

The unfavorable bioaccessibility of polyphenols in cereal-based food limits their physiological functions as most polyphenols bind spontaneously to the cell-wall polysaccharides. Effects of β-glucan and various thermal processing methods including flaking and roasting, stir-frying, steam-flash explosion, and popping expansion on the bioaccessibility and antioxidant properties of polyphenols from hulless barley in vitro and in vivo were investigated in this study. The bioaccessibility and antioxidant capacity (via DPPH, ·OH, and ·O₂^- free radical scavenging, TAC, and FRAP assays) of polyphenol extracts from hulless barley treated by steam-flash explosion and popping expansion increased significantly before and after in vitro digestion compared to those from raw and other processed hulless barley. Further, the total polyphenol content of hulless barley elevated dramatically following hydrolyzing with β-glucanase, which was positively correlated with the antioxidant activity. Additionally, the hulless barley treated with steam-flash explosion exhibited potent antidiabetic effects and antioxidant capacity (via TAC, SOD, GSH-Px, CAT, and MDA assays) in type 2 diabetic rats. The absorption of individual phenolic compounds in the alimentary canal of rats was impacted obviously by thermal processing. This study provides new insights into enhancing the bioaccessibility of the polyphenols and suggests that β-glucans interact with polyphenols and proteins in the hulless barley matrix.

Polyphenol and Anthocyanin Composition and Activity of Highland Barley with Different Colors

In this research, the composition of free phenols, bound phenols, and anthocyanins and their in vitro antioxidant activity and in vitro α-glucosidase inhibiting activity were observed in different barley colors. The outcomes revealed that the contents of total phenols (570.78 mg/100 gDW), total flavonoids (47.08 mg/100 gDW), and anthocyanins (48.07 mg/100 g) were the highest in purple barley. Furthermore, the structure, composition, and concentration of phenolics differed depending on the colors of barley. The types and contents of bound total phenolic acids and flavonoids were greater than those of free total phenolic acids and flavonoids. The main phenolic acids in blue barley were cinnamic acid polyphenols, whereas in black, yellow, and purple barley, benzoic acid polyphenols were the main phenolic acids, and the main types of flavonoids in black and blue barley were chalcones and flavanones, respectively, whereas flavonol was the main type of flavonoid in yellow and purple barley. Moreover, cornflower pigment-3-glucoside was the major anthocyanin in blue, yellow, and purple barley, whereas the main anthocyanin in black barley was delphinidin-3-glucoside. The dark color of barley indicated richness in the anthocyanins. In addition, the free polyphenol fractions had stronger DPPH and ABTS radical scavenging capacity as compared to the bound ones. In vitro α-glucosidase-inhibiting activity was greater in bound polyphenols than in free polyphenols, with differences between different varieties of barley. Purple barley phenolic fractions had the greatest ABTS radical scavenging and iron ion reduction capacities, as well as the highest α-glucosidase-inhibiting activity. The strongest DPPH radical scavenging capacity was found in yellow barley, while the strongest in vitro α-glucosidase-inhibiting activity was found in anthocyanins isolated from black barley. Furthermore, in different colors of barley, there was a strong association between the concentration of specific phenolic compounds and antioxidant and α-glucosidase-inhibiting activities. The outcomes of this study revealed that all colored barley seeds tested were high in phenolic compounds, and had a good antioxidant impact and α-glucosidase-inhibiting activity. As a result, colored barley can serve as an antioxidant and hypoglycemic food. Polyphenols extracted from purple barley and anthocyanins extracted from black barley stand out among them.

Effect of an Environment Friendly Heat and Relative Humidity Approach on γ-Aminobutyric Acid Accumulation in Different Highland Barley Cultivars

In this study, heat and relative humidity (HRH) treatment was applied in highland barley for γ-aminobutyric acid (GABA) accumulation. Tibetan highland barley cultivars (25) were selected for comparison and analysis. HRH treatment could accumulate GABA in several hours with low moisture content and high temperature, and the grains were treated for 2.5 h at 65 °C in this study. The GABA content of processed grains under HRH optimal condition ranged from 26.91 to 76.28 mg·100 g−1, which was significantly higher than the initial content (12.78−43.00 mg·100 g−1). The highest GABA accumulation capacity was observed in two-row yellow cultivars (YT1), increasing from 36.52 to 76.28 mg·100 g−1. Correlation analysis showed that the accumulation of GABA after HRH treatment was positively and significantly (p < 0.05) correlated with the contents of protein (0.52), total free amino acids (0.68), threonine (0.53), serine (0.51), glutamate (0.69), glycine (0.49), alanine (0.46), cysteine (0.57), tyrosine (0.50), lysine (0.53), proline (0.40), and glutamate decarboxylase (GAD) activity (0.62), which were closely related to GABA-shunt pathway. The polyamines contents, diamine oxidase (DAO) and polyamine oxidase (PAO) activities, as the substrates and critical enzymes of polyamine degradation pathway, showed no significant correlation with GABA accumulation. The results suggested that the main pathway of GABA accumulation in highland barley under HRH treatment was GABA-shunt pathway.

Beneficial Effects of Partly Milled Highland Barley on the Prevention of High-Fat Diet-Induced Glycometabolic Disorder and the Modulation of Gut Microbiota in Mice

The nutritional functions of highland barley (HB) are superior to those of regular cereals and have attracted increasing attention in recent years. The objective of this study was to investigate whether partly milled highland barley (PHB) can regulate the serum glucose and lipid disorders of mice fed a high-fat diet (HFD) and to further explore their potential gut microbiota modulatory effect. Our results showed that PHB supplementation significantly reduced fasting blood glucose (FBG) and improved oral glucose tolerance. Histological observations confirmed the ability of PHB to alleviate liver and intestine damage. Furthermore, the results of 16S amplicon sequencing revealed that PHB prevented a HFD-induced gut microbiota dysbiosis, enriching some beneficial bacteria, such as Lactobacillus, Bifidobacterium, and Ileibacterium, and reducing several HFD-dependent taxa (norank_f_Desulfovibrionaceae, Blautia, norank_f_Lachnospiraceae, unclassified_f_Lachnospiraceae, and Colidextribacter). In addition, the increase of Lactobacillus and Bifidobacterium presence has a slightly dose-dependent relationship with the amount of the added PHB. Spearman correlation analysis revealed that Lactobacillus and Bifidobacterium were negatively correlated with the blood glucose level of the oral glucose tolerance test. Overall, our results provide important information about the processing of highland barley to retain its hypoglycemic effect and improve its acceptability and biosafety.

Chemical Composition and Potential Biological Activity of Melanoidins From Instant Soluble Coffee and Instant Soluble Barley: A Comparative Study

In this work a comparative study of the chemical composition and potential biological activity of high molecular weight (HMW) melanoidins isolated from instant soluble coffee (ISC) and instant soluble barley (ISB) was performed. ISB HMW melanoidins were almost exclusively composed by an ethanol soluble (EtSn) melanoidin fraction composed by glucose (76% w/w) partially susceptible to in vitro digestion, whereas ISC was composed mainly by arabinogalactans (~41% w/w) and lower amounts of galactomannans (~14% w/w) presenting a range of ethanol solubilities and resistant to in vitro digestion. Melanoidins from ISC presented a significantly higher content of condensed phenolic compounds (17/100 g) when compared to ISB (8/100 g) showing also a higher in vitro scavenging of ABTS•+ (329 mmol Trolox/100 g vs. 124 mmol Trolox/100 g) and NO radicals (inhibition percentage of 57 and 26%, respectively). Nevertheless, ISB EtSn melanoidins presented, on average a higher inhibitory effect on NO production from LPS-stimulated macrophages. ISB melanoidins, up to 1 mg/mL, did not induce toxicity in Caco-2, HepG2 and RAW 264.7 cell lines while at the highest concentration ISC slightly reduced cell viability. Thus, consumption of a diet rich in ISC and ISB melanoidins may reduce the oxidative stress, the inflammatory levels and increase the protective effects against chronic inflammatory diseases.

Synergistic effects and antityrosinase mechanism of four plant polyphenols from Morus and Hulless Barley

Sanggenone C, oxyresveratrol, catechin and l-epicatechin exist in Morus and Hulless Barley as natural polyphenols with antityrosinase activity. Little research on their synergistic and structure-function relationships of them has been reported in recent years. In this paper, the inhibition mechanisms of these four plant polyphenols were investigated by enzyme kinetics, HPLC, fluorescence spectra, and molecular docking methods. The results showed that oxyresveratrol (IC₅₀ = 1.096 ± 0.048 μg/mL), sanggenone C (IC₅₀ = 13.360 ± 1.029 μg/mL), l-epicatechin (IC₅₀ = 55.730 ± 1.762 μg/mL), and catechin (IC₅₀ = 148.500 ± 3.355 μg/mL) exhibited tyrosinase inhibition activity. When sangenone C (14 μg/mL) was mixed with l-epicatechin (56 μg/mL) at 4:1 (40 μL + 10 μL), the highest tyrosinase inhibition was achieved. Molecular docking showed that the number and position of phenolic hydroxyls of polyphenols were the key for tyrosinase inhibition activity. This study provided new ideas for the application of these four plant polyphenols from Hulless Barley and Morus as tyrosinase inhibitors in food preservation.

Variation of Phenolics (Bound and Free), Minerals, and Antioxidant Activity of Twenty-Eight Wild Edible Fruits of Twenty-Three Species from Far North Region of Cameroon

The present study is aimed at investigating the variation of phenolics (bound and free), minerals, and antioxidant potentials of the wild edible fruits (fresh and dry) native from Far North Region of Cameroon. The results showed significant (p < 0.01) differences among fruits and species for all parameters. Bound phenolic content (mgGAE/100 g) of dry fruits (DF) ranged from 95.58 to 407.72; however, the contents were varied from 28.97 to 306.04 in fresh fruits (FF). Free phenolic content varied from 46.43 to 344.73 in DF and fold from 119.54 to 315.79 for those FF. Flavonoids (4.27-256.87 mg QE/100 g), tannins (3.24-63.42 mg CE/100 g), and anthocyanin content (8.65-168.10 mg C3GE/100 g) in fruits varied also significantly in respect with DF and FF. The mineral content analysis indicates that the wild fruits are rich in valuable macro- and trace elements. For antioxidant activities, except high 2.2-diphenyl-1-picyhydrazyl (DPPH) scavenging activity obtained with free phenolics, the bound phenolics of FF and DF had significantly high ferric reducing antioxidant power (FRAP) and 2,2-azino-bis(3-ethylbenzylthiozoline-6-sulphonic acid) (ABTS) scavenging activity. Furthermore, free and bound phenolic content was highly and positively correlated with ABTS, DPPH, and FRAP activities confirmed by the principal component analysis (F1×F2: 60.17%). The present study revealed that the wild edible fruits of twenty-three species investigated are important sources of bioactive compounds, natural antioxidants, and nutraceutical potential to prevent/to treat chronic diseases which could be benefits for the consumers.