UHPLC-ESI-QTOF-MS/MS characterization, antioxidant and antidiabetic properties of sorghum grains

Advanced Glycation End Products and Health: A Systematic Review

Advanced glycation end products (AGEs) have garnered significant attention due to their association with chronic diseases and the aging process. The prevalence of geriatric diseases among young individuals has witnessed a notable surge in recent years, potentially attributed to the accelerated pace of modern life. The accumulation of AGEs is primarily attributed to their inherent difficulty in metabolism, which makes them promising biomarkers for chronic disease detection. This review aims to provide a comprehensive overview of the recent advancements and findings in AGE research. The discussion is divided into two main sections: endogenous AGEs (formed within the body) and exogenous AGEs (derived from external sources). Various aspects of AGEs are subsequently summarized, including their production pathways, pathogenic mechanisms, and detection methods. Moreover, this review delves into the future research prospects concerning AGEs. Overall, this comprehensive review underscores the importance of AGEs in the detection of chronic diseases and provides a thorough understanding of their significance. It emphasizes the necessity for further research endeavors to deepen our comprehension of AGEs and their implications for human health.

Investigating the involvement of the NLRP3/ASC/caspase-1 and NF-κb/MAPK pathways in the pathogenesis of gouty arthritis: Insights from irradiated and non-irradiated Trifolium alexandrium L. extracts and some metabolites

ETHNOPHARMACOLOGICAL RELEVANCE

Trifolium alexandrinum L. (TA), has traditionally been used in folk medicine for its anti-inflammatory properties against hyperuricemia and gout. However, the specific mechanisms of action of TA have not been thoroughly studied.

AIM OF THE WORK

This study aimed to evaluate the protective effects of irradiated (TR25) and non-irradiated (TR0) Trifolium alexandrinum L. aqueous extract (TAAE), along with two isolated compounds, caffeine (CAF) and saponin (SAP), in a rat model of acute gouty arthritis (GA).

MATERIALS AND METHODS

The GA model was established by injecting a monosodium urate (MSU) suspension into the knee joint. Synovial tissue pathology was assessed, and levels of TNF-α, IL-6, IL-1β, NF-κB, mTOR, AKT1, PI3K, NLRP3, and ASC were measured by ELISA. mRNA expression of ERK1, JNK, and p-38 MAPK was detected using qRT-PCR, and Caspase-1 protein expression was assessed by immunohistochemical analysis. Knee swelling, uric acid levels, liver and kidney function, and oxidative stress markers were also evaluated.

RESULTS

TAAE analysis identified 170 compounds, with 73 successfully identified using LC-HR-MS/MS, including caffeine citrate and theasapogenol B glycoside as the main constituents. The studied materials demonstrated significant protective effects against GA. TR25 administration significantly mitigated knee joint circumference compared to other treatments. It demonstrated potential in alleviating hyperuricemia, renal and hepatic impairments induced by MSU crystals. TR25 also alleviated oxidative stress and reduced levels of IL1β, IL-6, TNF-α, and NF-κB. Weak Caspase-1 immune-positive staining was observed in the TR25 group. TR25 decreased NLRP3 and ASC expression, reducing inflammatory cytokine levels in GA. It effectively inhibited the PI3K, AKT, and mTOR signaling pathways, promoting autophagy. Additionally, TR25 suppressed ERK1, JNK, and p-38 MAPK gene expression in synovial tissue. These effects were attributed to various components in TAAE, such as flavonoids, phenolic acids, tannins, alkaloids, and triterpenes.

CONCLUSION

Importantly, irradiation (25 KGy) enhanced the antioxidant effects and phtchemical contents of TAAE. Additionally, TR0, TR25, CAF, and SAP exhibited promising protective effects against GA, suggesting their therapeutic potential for managing this condition. These effects were likely mediated through modulation of the NLRP3/ASC/Caspase-1 and ERK/JNK/p-38 MAPK signaling pathways, as well as regulation of the PI3K/AKT/mTOR pathway. Further research is warranted to fully elucidate the underlying mechanisms and optimize their clinical applications.

A colorimetric sensing strategy based on chitosan-stabilized platinum nanoparticles for quick detection of α-glucosidase activity and inhibitor screening

α-Glucosidase (α-Glu) is implicated in the progression and pathogenesis of type II diabetes (T2D). In this study, we developed a rapid colorimetric technique using platinum nanoparticles stabilized by chitosan (Ch-PtNPs) to detect α-Glu activity and its inhibitor. The Ch-PtNPs facilitate the conversion of 3,3',5,5'-tetramethylbenzidine (TMB) into oxidized TMB (oxTMB) in the presence of dissolved O2. The catalytic hydrolysis of 2-O-α-D-glucopyranosyl-L-ascorbic acid (AA-2G) by α-Glu produces ascorbic acid (AA), which reduces oxTMB to TMB, leading to the fading of the blue color. However, the presence of α-Glu inhibitors (AGIs) hinders the generation of AA, allowing Ch-PtNPs to re-oxidize colorless TMB back to blue oxTMB. This unique phenomenon enables the colorimetric detection of α-Glu activity and AGIs. The linear range for α-Glu was found to be 0.1-1.0 U mL-1 and the detection limit was 0.026 U mL-1. Additionally, the half-maximal inhibition value (IC50) for acarbose, an α-Glu inhibitor, was calculated to be 0.4769 mM. Excitingly, this sensing platform successfully detected α-Glu activity in human serum samples and effectively screened AGIs. These promising findings highlight the potential application of the proposed strategy in clinical diabetes diagnosis and drug discovery.

Novel approach on the evaluation of enzyme-aided alkaline extraction of polysaccharide from Hordeum vulgare husk and molecular insight on the multifunctional scaffold

Hordeum vulgare husk, a cereal grain, is rich in dietary fiber and prebiotics beneficial for the gut microbiota and host organism. This study investigates the effects of barley husk-derived water-soluble xylan (BH-WSX) on gut homeostasis and the microbiome. We enzymatically extracted BH-WSX and evaluated its prebiotic and antioxidant properties. A 40.0 % (w/v) xylan yield was achieved, with the extracted xylan having a molecular mass of 212.0885 and a xylose to glucuronic acid molar ratio of 6:1. Specialized optical rotation research indicated that the isolated xylan is composed of monomeric sugars such as D-xylose, glucose, and arabinose. Fourier Transform Infrared (FTIR) spectroscopy revealed that the xylan comprises β (1 → 4) linked xylose units, randomly substituted with glucose residues, α-arabinofuranose, and acetyl groups. Nuclear Magnetic Resonance (NMR) analysis showed that the barley husk extract's backbone is substituted with 4-O-methyl glucuronic acid at the O2 position. Thermogravimetric analysis indicated that WSX exhibits a single sharp peak at 266 °C on the Differential Thermal Gravimetry (DTG) curve. Furthermore, a combination of in vitro, in vivo models, and molecular docking analysis elaborated on the anti-adhesion properties of BH-WSX. This study presents a novel approach to utilizing barley husk as an efficient source of functional polysaccharides for food-related industrial applications.

Nontargeted Lipidomics of Sorghum Grain Reveals Novel Fatty Acid Esters of Hydroxy Fatty Acids and Cultivar Differences in Lipid Profiles

Sorghum, a globally grown gluten-free cereal, is used mainly as an animal feed in developed countries regardless of its potential for human consumption. In this study, we utilized nontargeted lipidomics to thoroughly analyze, compare, and characterize whole-grain lipids in six sorghum cultivars (cv) grown in a single field trial in Australia: Buster, Bazley, Cracker, Liberty, MR43, and Tiger. In total, 194 lipid molecular species representing five major lipid classes were identified. Multivariate analysis unveiled distinct lipid profiles among the cultivars. The most distinct lipid profile belonged to cv. MR43. The lower ω-6 to ω-3 ratio and optimal P/S ratio in cv. Bazley reflect this as a valuable source of balanced essential fatty acids in the diet. The novel bioactive lipids known as FAHFAs (fatty acid esters of hydroxy fatty acids) were identified and characterized in sorghum grains. These findings further emphasize the potential of whole-grain sorghum as a basis for new health-promoting food products.

Gomes PW, Fernández-Ochoa Á, Simões Larraz Ferreira M. Overview of the Metabolite Composition and Antioxidant Capacity of Seven Major and Minor Cereal Crops and Their Milling Fractions

Cereal grains play an important role in human health as a source of macro- and micronutrients, besides phytochemicals. The metabolite diversity was investigated in cereal crops and their milling fractions by untargeted metabolomics ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) of 69 samples: 7 species (barley, oat, pearl millet, rye, sorghum, triticale, and wheat), 23 genotypes, and 4 milling fractions (husk, bran, flour, and wholegrain). Samples were also analyzed by in vitro antioxidant activity. UHPLC-MS/MS signals were processed using XCMS, and metabolite annotation was based on SIRIUS and GNPS libraries. Bran and husk showed the highest antioxidant capacity and phenolic content/diversity. The major metabolite classes were phenolic acids, flavonoids, fatty acyls, and organic acids. Sorghum, millet, barley, and oats showed distinct metabolite profiles, especially related to the bran fraction. Molecular networking and chemometrics provided a comprehensive insight into the metabolic profiling of cereal crops, unveiling the potential of coproducts and super cereals such as sorghum and millet as sources of polyphenols.

Exploring the Potential of Anthocyanin-Based Edible Coatings in Confectionery-Temperature Stability, pH, and Biocapacity

This study aims to develop purple-coloured polymeric coatings using natural anthocyanin and desoxyanthocianidins (3-DXA) colourants for application to chocolate almonds. The objective is to achieve a stable and uniform colour formulation throughout processing and storage, enhancing the appearance and durability of the almonds to appeal to health-conscious consumers and align with market demands. Plant materials like sweet potato pulp, sweet potato peel, radish peel, black carrot, and sorghum were employed to obtain the desired purple hue. Anthocyanidins and 3-DXA were extracted from the matrices using solvent extraction and ultrasound-assisted methods at different pH values. High-performance liquid chromatography with diode array detection (HPLC-DAD) and high-resolution tandem mass spectrometry (HRMS/MS) were used to identify the compounds in the extracts. The highest antioxidant capacities, as measured by the DPPH• and FRAP methods, were observed in purple sweet potato and dye factory extracts, respectively; meanwhile, sorghum extract inhibited both α-amylase and α-glucosidase, indicating its potential for managing postprandial hyperglycemia and type 2 diabetes. The degradation kinetics of coloured coatings in sugar syrup formulations with anthocyanins and 3-DXA revealed that locust bean gum offered the best colour stabilization for plant extracts, with sorghum extracts showing the highest and black carrot extracts the lowest colour variation when coated with Arabic gum. Sweet potato pulp extracts exhibited less colour variation in sugar pastes, both with and without blue spirulina dye, compared to factory dye, highlighting their potential as a more stable and suitable alternative for colouring purple almonds, particularly over a five-month storage period. This study supports sustainable practices in the confectionery industry while aligning with consumer preferences for healthier and environmentally friendly products.

Sweet tea extract encapsulated by different wall material combinations with improved physicochemical properties and bioactivity stability

Aim: To prepare sweet tea extract microcapsules (STEMs) via a spray-drying by applying different wall material formulations with maltodextrin (MD), inulin (IN), and gum arabic (GA). Methods: The microcapsules were characterised by yield, encapsulation efficiency (EE), particle size, sensory evaluation, morphology, attenuated total reflectance-Fourier transform infra-red spectroscopy and in vitro digestion studies. Results: The encapsulation improved the physicochemical properties and bioactivity stability of sweet tea extract (STE). MD5IN5 had the highest yield (56.33 ± 0.06% w/w) and the best EE (e.g. 88.84 ± 0.36% w/w of total flavonoids). MD9GA1 obtained the smallest particle size (642.13 ± 4.12 nm). MD9GA1 exhibited the highest retention of bioactive components, inhibition of α-glucosidase (96.85 ± 0.55%), α-amylase (57.58 ± 0.99%), angiotensin-converting enzyme (56.88 ± 2.20%), and the best antioxidant activity during in vitro gastrointestinal digestion. Conclusion: The encapsulation of STE can be an appropriate way for the valorisation of STE with improved properties.

Sorghum (Sorghum bicolor L. Moench) Gluten-Free Bread: The Effect of Milling Conditions on the Technological Properties and In Vitro Bioaccessibility of Polyphenols and Minerals

The absence of gluten proteins in sorghum allows for the production of baked goods that are suitable for celiacs. Previous studies have shown that the milling process affects the performance of sorghum flour in baked products, especially those that are gluten-free (GF). This study aimed to explore the effects of mill type (impact and roller) on flour properties and GF bread quality by assessing the technological quality, antioxidant activity, and mineral content of the bread. All particle populations of flour obtained via both millings presented a bimodal distribution, and the volume mean diameter (D 4,3) ranged from 431.6 µm to 561.6 µm. The partially refined milled flour obtained via polishing and impact milling produced bread with a soft crumb, fewer but larger alveoli in the crumb, and a structure that did not collapse during baking, showing the best performance in bread quality. In the in vitro bread digestibility assay, the total polyphenol content and antioxidant activity decreased during the digestion steps. High mineral (Cu, Fe, Mn, and Zn) contents were also found in a portion of the bread (120 g) made with whole sorghum flour; however, their potential bioavailability was reduced in the presence of a higher amount of bran.

Exploring the potentials of sorghum genotypes: a comprehensive study on nutritional qualities, functional metabolites, and antioxidant capacities

Introduction

Sorghum, long regarded as one of the most underutilized crops, has received attention in recent years. As a result, conducting multidisciplinary studies on the potential and health benefits of sorghum resources is vital if they are to be fully exploited. In this study, the nutritional contents, functional metabolites, and antioxidant capacities of 23 sorghum breeding lines and three popular cultivars were assessed.

Materials and method

All of the sorghum genotypes were grown under the same conditions, and mature seeds were hand-harvested. The metabolite contents and antioxidant capacities of sorghum seeds were assessed using standard protocols. Fatty acids were quantified using a gas chromatography-flame ionization detector, whereas flavonoids and 3-deoxyanthocyanidins were analyzed using a liquid chromatography-tandem mass spectrometry method. The data were analyzed using both univariate and multivariate statistical approaches.

Results and discussion

Total protein (9.05-14.61%), total fat (2.99-6.91%), crude fiber (0.71-2.62%), dietary fiber (6.72-16.27%), total phenolic (0.92-10.38 mg GAE/g), and total tannin (0.68-434.22 mg CE/g) contents varied significantly across the sorghum genotypes (p < 0.05). Antioxidant capacity, measured using three assays, also differed significantly. Five fatty acids, including palmitic, stearic, oleic, linoleic, and linolenic acids, were found in all the sorghum genotypes with statistically different contents (p < 0.05). Furthermore, the majority of the sorghum genotypes contained four 3-deoxyanthocyanidins, including luteolinidin, apigeninidin, 5-methoxyluteolinidin, and 7-methoxyapigeninidin, as well as two dominant flavonoids, luteolin and apigenin. Compared to the cultivars, some breeding lines had significantly high levels of metabolites and antioxidant activities. On the other hand, statistical analysis showed that total tannin, total phenolic, and antioxidant capacities varied significantly across white, yellow, and orange genotypes. Principal component analysis was used to differentiate the sorghum genotypes based on seed color and antioxidant index levels. Pearson's correlation analysis revealed strong links between biosynthetically related metabolites and those with synergistic antioxidant properties.

Conclusion

This research demonstrated the diversity of the sorghum resources investigated. Those genotypes with high levels of nutritional components, functional metabolites, and antioxidant activities could be used for consumption and breeding programs.

Metabolomics based inferences to unravel phenolic compound diversity in cereals and its implications for human gut health

Background

Scope and approach

Key findings and conclusion

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Phenolic compounds are critical in avoiding metabolic disorders associated with oxidative stress.

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Breeding cereal crops to enrich phenolic compounds in grains contributes to personalized nutrition.

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A diet rich in cereal phenolics likely to increase human gut health, thereby lowering the risk of non-communicable illness.

Genetic diversity for agromorphological traits, phytochemical profile, and antioxidant activity in Moroccan sorghum ecotypes

Sorghum, the fifth most important cereal crop, is a well-adapted cereal to arid/semi-arid regions. Sorghum is known for multiple end-uses as food, feed, fuel, forage, and as source of bioactive compounds that could be used for medical applications. Although the great improvement in the process of sorghum breeding, the average yield of this crop is still very low. Therefore, exploring the genetic diversity in sorghum accessions is a critical step for improving this crop. The main objective of the current work was to study the genetic variation existing in a Moroccan sorghum collection. Indeed, 10 sorghum ecotypes were characterized based on agromorphological descriptors. Both quantitative (25) and qualitative (7) traits revealed variability (p < 0.05) among the studied ecotypes. At the seedling stage, most of the ecotypes showed good to high vigor (70%). However, as the sorghum plants grow, the difference between genotypes become more apparent, especially at the generative phase. For instance, three different panicle shapes have been observed, erect (50%), semi-bent (30%), and bent (20%) with different degree of compactness (20% for loose, semi-compact, and compact panicles, and 30% for semi-loose panicles). In another part of this study, the phytochemical composition and antioxidant activities of the sorghum ecotypes have been determined. The results showed variable total phenolic contents, and total flavonoid contents ranging from 125.86 ± 1.36 to 314.91 ± 3.60 mg GAE/g dw and 114.0 ± 13.2 to 138.5 ± 10.8 (mg catechin equivalent/100 g, dw) respectively, with a differential antioxidant activities as well. These results indicate that for any crop breeding program, it is preferable to take into consideration both morphological and biochemical traits for a better selection of high yielding varieties with high added value compounds. Therefore, the implication of these results in the context of sorghum breeding activities could be a resourceful option for farmers.

A review of extrusion-modified underutilized cereal flour: chemical composition, functionality, and its modulation on starchy food quality

Compared with three major cereals, underutilized cereals (UCs) are those with less use but having abundant bioactive components and better functionalities after proper processing. As a productive and energy-efficient technology, extrusion has been used for UC modification to improve its technological and nutritional quality. Extrusion could induce structural and quantitative changes in chemical components of UC flour, the degree of which is affected by extrusion intensity. Based on the predominant component (starch), functionalities of extruded underutilized cereal flour (EUCF) and potential mechanisms are reviewed. Considering bioactive compounds, it also summarizes the physiological functions of EUCF. EUCF incorporation could modulate the dough rheological behavior and starchy foods quality. Controlling extrusion intensity or incorporation level of EUCF is vital to achieve sensory-appealing and nutritious products. This paper gives comprehensive information of EUCF to promote its utilization in novel staple foods.

Generation, characterization and molecular binding mechanism of novel dipeptidyl peptidase-4 inhibitory peptides from sorghum bicolor seed protein

Food proteins and their constituent peptides impart huge health benefits besides their nutritional attributes. Sorghum bicolor protein hydrolysates (SPH) and derived bioactive peptides generated by simulated gastrointestinal digestion were studied for DPP-4 inhibitory properties using in vitro and in situ assays. Identified peptides, LSICGEESFGTGSDHIR (PEP1), SLGESLLQEDVEAHK (PEP2) and QLRDIVDK (PEP4) displayed potent DPP-4 inhibition with IC50 values of 73.5, 82.5 and 8.55 µM respectively. DPP-4 inhibition mechanism by the peptides was investigated by DPP4-peptide inhibition kinetics, molecular docking and microscale thermophoresis binding studies. The peptides bound to DPP-4 with micromolar affinities and PEP4 showed significantly increased affinity. The mixed type enzyme inhibition by peptides suggested that the peptides either block the active site of DPP-4 or changes the enzyme conformation via a secondary binding site. Overall, the results demonstrate that sorghum seeds are an adequate source of peptides with DPP-4 inhibitory properties that could be used in functional food formulations.

Comprehensive profiling of bioactive compounds in germinated black soybeans via UHPLC-ESI-QTOF-MS/MS and their anti-Alzheimer's activity

Black soybeans contain several bioactive compounds and commonly consumed due to their health-related activities but rarely cultivated as edible sprouts. The present study investigated the changes that occurred during germination in two new genotypes black soybeans. Raw and germinated seeds were tested against in vitro Alzheimer's disease (AD) biomarkers, including oxidative stress, inflammatory factors and cholinesterase enzymes as well as γ-aminobutyric acid (GABA) levels. Sprouts significantly inhibited the cholinesterase enzymes and inflammatory factors (protein denaturation, proteinase and lipoxygenase) than seeds. An increase in phenolic, flavonoid and GABA (10-folds) content and antioxidant capacity (ABTS, DPPH, and FRAP) was observed in germinated seeds. However, anthocyanin content was decreased in sprouts. UHPLC-ESI-QTOF-MS2 metabolites profiling approach identified 22 compounds including amino acids, peptides, fatty acids, and polyphenols. Among identified compounds, daidzein, genistein, gallic acid, spermidine, L-asparagine, and L-lysine exhibited the highest increase after germination. The current study reveals that germination of black soybeans have promising potential to inhibit/prevent AD and can be used to develop functional foods.

Potential food applications of sorghum (Sorghum bicolor) and rapid screening methods of nutritional traits by spectroscopic platforms

Sorghum is a drought-resistant crop widely spread in tropical regions of the American, African, and Asian continents. Sorghum flour is considered the main alternative for wheat flour, and it exhibits gluten-free nature. Generally, conventional wet chemical methods are used to analyze the nutritional profile of sorghum. Since many sorghum plants are available in breeding grounds, the application of conventional methods has limitations due to high cost and time consumption. Therefore, rapid screening protocols have been introduced as nondestructive alternatives. The current review highlights novel and portable devices that can be used to analyze the nutritional composition, color parameters, and pest resistance. Sorghum is often a traditional food item with minimal processing, and the review elaborates on emerging food applications and feasible food product developments from sorghum. The demand for gluten-free products has been rapidly increasing in developed countries. In order to develop food products according to market requirements, it is necessary to screen high-quality sorghum plants. Rapid analysis techniques effectively select the best sorghum types, and the novel tools have outperformed existing conventional methods.

Bioactive Compounds and Biological Activities of Sorghum Grains

Sorghum is the fifth most commonly used cereal worldwide and is a rich source of many bioactive compounds. We summarized phenolic compounds and carotenoids, vitamin E, amines, and phytosterols in sorghum grains. Recently, with the development of detection technology, new bioactive compounds such as formononetin, glycitein, and ononin have been detected. In addition, multiple in vitro and in vivo studies have shown that sorghum grains have extensive bio-logical activities, such as antioxidative, anticancer, antidiabetic, antiinflammatory, and antiobesity properties. Finally, with the establishment of sorghum phenolic compounds database, the bound phenolics and their biological activities and the mechanisms of biological activities of sorghum bioactive compounds using clinical trials may be researched.

UPLC-QTOF-MS/MS and GC-MS Characterization of Phytochemicals in Vegetable Juice Fermented Using Lactic Acid Bacteria from Kimchi and Their Antioxidant Potential

This study aims to investigate fermentative metabolites in probiotic vegetable juice from four crop varieties (Brassica oleracea var. capitata, B. oleracea var. italica, Daucus carota L., and Beta vulgaris) and their antioxidant properties. Vegetable juice was inoculated with two lactic acid bacteria (LAB) (Companilactobacillus allii WiKim39 and Lactococcus lactis WiKim0124) isolated from kimchi and their properties were evaluated using untargeted UPLC-QTOF-MS/MS and GC-MS. The samples were also evaluated for radical (DPPH^• and OH^•) scavenging activities, lipid peroxidation, and ferric-reducing antioxidant power. The fermented vegetable juices exhibited high antioxidant activities and increased amounts of total phenolic compounds. Fifteen compounds and thirty-two volatiles were identified using UPLC-QTOF-MS/MS and GC-MS, respectively. LAB fermentation significantly increased the contents of d-leucic acid, indole-3-lactic acid, 3-phenyllactic acid, pyroglutamic acid, γ-aminobutyric acid, and gluconic acid. These six metabolites showed a positive correlation with antioxidant properties. Thus, vegetable juices fermented with WiKim39 and WiKim0124 can be considered as novel bioactive health-promoting sources.

Phenolic Compounds in Whole Grain Sorghum and Their Health Benefits

Sorghum grain (Sorghum bicolor L. Moench) is a staple food grown across the globe, and is mainly cultivated in the semi-arid regions of Africa and Asia. Recently, sorghum grain is increasingly utilized for human consumption, due to the gluten-free nature and potential phenolic-induced health benefits. Sorghum grain is rich in bioactive phenolic compounds, such as ferulic acid, gallic acid, vanillic acid, luteolin, and apigenin, 3-deoxyanthocyanidins (3-DXA), which are known to provide many health benefits, including antioxidant, anti-inflammatory, anti-proliferative, anti-diabetic, and anti-atherogenic activities. Given an increasing trend of sorghum consumption for humans, this article reviews the content and profile of phenolics in sorghum. It covers aspects of their health benefits and explores their mechanisms of action. The impact of thermal processing, such as boiling, steaming, roasting, and extrusion on sorghum phenolics is also discussed. Compelling data suggest the biological functions of sorghum phenolics, however, further investigations appear warrant to clarify the gap in the current research, and identify promising research topics in future.

Chemical Composition Profiling and Biological Activities of Phenolic Compounds in Eleven Red Sorghums

The profiles of soluble and insoluble phenolic compounds in 11 commercial red sorghums (B11, B12, B13, B14, J124, J127, J138, J140, J142, J152, and J158) were investigated using ultraperformance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS) analysis. A total of 48 phenolic compounds including 35 phenolic acids and their derivatives, 12 flavonoids, and 1 proanthocyanidin were identified, and 8 phenolic compounds were reported for the first time in sorghums. Four major 3-deoxyanthocyanidins were also quantified, with their soluble forms accounting for 99.75-99.87% of the total contents. Pearson's correlation analyses indicated that 3-deoxyanthocyanidins significantly contributed to the antioxidant capacities of the red sorghums and that 5-methoxy-luteolinidin showed the strongest correlation. Besides, the soluble phenolic fraction of B13 dose-dependently inhibited the proliferation of Caco-2 cells and the secretion of IL-1β and NO in RAW264.7 macrophages, which might be attributed to its relatively high total phenolic (TPC), flavonoid (TFC), and proanthocyanidin content (TPAC) values and radical scavenging capacities.

Sorghum polyphenols: plant stress, human health benefits, and industrial applications

MAIN CONCLUSION

Various phenolic compounds of sorghum are effective in the management of abiotic stress (salt, nutrients) and biotic stress (caused by birds, fungi and aphids). The health and industrial application of phenolics is mainly contributed by inherent antioxidant and nutraceutical potential. In a natural environment, plant growth is affected by various biotic and abiotic stresses. In every ecosystem, the presence of a wide range of harmful biological agents (bacteria, fungi, nematodes, mites, and insects) and undesirable environmental factors (drought, salinity, heat, excessive or low rainfall, etc.) may cause a heavy loss in crop productivity. Being sessile during evolution, plants have evolved multiple defense mechanisms against various types of microbial pathogens and environmental stresses. A plant's natural defense system produces some compounds named secondary metabolites, which include phenolics, terpenes, and nitrogen. The phenolic profile of grain sorghum, the least utilized staple crop, is unique, more diverse, and more abundant than in any other common cereal grain. It mainly contains phenolic acids, 3-deoxyanthocyanidins and condensed tannins. Sorghum polyphenols play a major role in plant defense against biotic and abiotic stresses and have many additional health benefits along with various industrial applications. The objective of this review is to discuss the phenolic compounds derived from grain sorghum and describe their role in plant defense, human health, and industrial applications.

α-Glucosidase inhibitory triterpenoids from Euonymus fortunei

α-Glucosidase plays an important role in catalyzing the hydrolytic cleavage of disaccharides into monosaccharides. In this study, a phytochemical investigation of the potential α-glucosidase inhibitory fraction from the aerial parts of Euonymus fortunei led to the isolation and identification of two new tetracyclic triterpenoids, fortunenones A and B (1-2), together with 11 known triterpenoids (3-13). Fortunenones A and B are rare C₃₂ triterpenoids possessing a 24,24-dimethyl group. The partial isolated compounds were evaluated their effects on α-glucosidase, of which echinochlorin D (5), lupenone (7), wilforlide B (12), and wilforlide A (13) exhibited remarkable inhibitory effects with the half inhibitory concentration ranged from 207.2 × 10^-6 M to 388.3 × 10^-6 M compared with the positive control, acarbose. An enzyme kinetics analysis by Lineweaver-Burk plots revealed that the inhibition types of the four active compounds were all mixed inhibition. Molecular docking further revealed that hydrophobic interactions and hydrogen bonds play an important role in the inhibition of α-glucosidase activity. Our results demonstrate the potential of E. fortunei extract and its constituents to inhibit α-glucosidase.

Exploring Molecular Insights of Cereal Peptidic Antioxidants in Metabolic Syndrome Prevention

The prevalence of metabolic syndrome (MetS) is presently an alarming public health problem globally. Oxidative stress has been postulated to be strongly correlated with MetS, such as type 2 diabetes, obesity, hypertension, cardiovascular diseases, and certain cancers. Cereals are important staple foods which account for a huge proportion of the human diet. However, owing to recent growing demand and the search for natural antioxidants for the prevention and management of MetS, cereal peptides have gained increasing attention for developing functional ingredients or foods with substantial antioxidant properties. This review explores the current production techniques for cereal peptidic antioxidants and their potential mechanism of action in the prevention and management of MetS.

A colorimetric sensing strategy based on enzyme@metal-organic framework and oxidase-like IrO2/MnO2 nanocomposite for α-glucosidase inhibitor screening

A highly sensitive colorimetric sensing strategy based on enzyme@metal-organic framework (GAA@Cu-MOF) and IrO₂/MnO₂ nanocomposite was exploited innovatively for screening of α-glucosidase (GAA) inhibitors. IrO₂/MnO₂ nanocomposite exhibits excellent oxidase-mimicking activity which can directly catalyze the oxidation of 3,3^,5,5^,-tetramethylbenzidine (TMB) into a blue product with an absorption maximum at 652 nm. And GAA@Cu-MOF can decompose L-ascorbic acid-2-O-α-D-glucopyranosyl (AAG) to ascorbic acid (AA). The produced AA can destroy the IrO₂/MnO₂ nanocomposite and reduce its oxidase-like activity. However, the generation of AA is restricted when GAA inhibitors are added to the system, which allows the oxidase-like activity of the IrO₂/MnO₂ nanocomposite to be maintained. In view of this, a method for screening of GAA inhibitors was developed. In addition to enhancing the stability of GAA, the method can also effectively avoid the potential interference of H₂O₂ in the screening process of GAA inhibitors, which helps to improve the sensitivity of the method. Therefore, highly sensitive determination for acarbose and ascorbic acid are achieved with detection limits of 6.27 nM and 1.23 μM, respectively. The proposed method was successfully applied to screen potential GAA inhibitors from oleanolic acid derivatives. Graphical abstract.