The phenolic compounds profile, quantitative analysis and antioxidant activity of four naked barley grains with different color

Assessing the influences of β-glucan on highland barley starch: Insights into gelatinization and molecular interactions

Developing highland barley products is complex, possibly due to the presence of β-glucan in highland barley. This study aims to investigate the impact of β-glucan on the physicochemical properties, microstructure, and molecular interactions of highland barley starch (HBS) during gelatinization and aging. Increasing the β-glucan content significantly reduced peak viscosity, setback viscosity, and breakdown viscosity, indicating altered gelatinization behavior. The β-glucan content increase caused a significant drop in peak viscosity. With 20% β-glucan addition, it reduced by 883 mPa·s, nearly 38%. Rheological analysis showed a transition from a solid-like to a liquid-like texture or quality, ultimately leading to a shear-thinning behavior. Fourier-transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) confirmed the interaction between HBS and β-glucan via intermolecular hydrogen bonding, promoting the formation of double helical structures in starch. These findings provide a deeper understanding of the role of β-glucan in the processing of highland barley, highlighting its influence on the starch's properties.

Metabolic basis for superior antioxidant capacity of red-fleshed peaches

Peach fruit is an important natural source of phenolic compounds that are well-known to have health benefits, but their metabolic basis remain elusive. Here, we report on phenolic compounds accumulation and antioxidant activity of ripe fruits in peach. A considerable variation in phenolic compounds content was observed among peach germplasm, with significantly higher levels detected in red-fleshed peaches compared to non-red-fleshed peaches. Antioxidant activity of crude extracts from ripe fruits showed significant differences among peach germplasm, with red-fleshed peaches having the strongest antioxidant activity. Intriguingly, it was observed that total phenolics instead of anthocyanins were strongly associated with antioxidant activity. Phenolic compounds content and antioxidant activity showed dynamic changes throughout fruit development, and these were much higher in the peel than in the flesh. Metabolomic analysis unveiled a coordinated accumulation of anthocyanins as well as key components of flavonoids and phenolic acids, which endows red-fleshed peaches with superior antioxidant activity.

Barley-derived beer brewing by-products contain a high diversity of hydroxycinnamoylagmatines and their dimers

To aid valorisation of beer brewing by-products, more insight into their composition is essential. We have analysed the phenolic compound composition of four brewing by-products, namely barley rootlets, spent grain, hot trub, and cold trub. The main phenolics detected were hydroxycinnamoylagmatines and dimers thereof. Barley rootlets contained the highest hydroxycinnamoylagmatine content and cold trub the highest dimer content. Additionally, variations in (dimeric) hydroxycinnamoylagmatine composition and content were observed in fourteen barley rootlet samples. The most abundant compound in all rootlets was the glycosylated 4-O-7'/3-8'-linked heterodimer of coumaroylagmatine and feruloylagmatine, i.e. CouAgm-4-O-7'/3-8'-(4'Hex)-DFerAgm. Structures of glycosylated and hydroxylated derivatives of coumaroylagmatine were elucidated by NMR spectroscopy after their purification from a rootlet extract. An MS-based decision tree was developed, which aids in identifying hydroxycinnamoylagmatine dimers in complex mixtures. In conclusion, this study shows that the diversity of phenolamides and (neo)lignanamides in barley-derived by-products is larger than previously reported.

Peruvian fava beans for health and food innovation: physicochemical, morphological, nutritional, and techno-functional characterization

Peruvian fava beans (PFB) are used in traditional cuisine as a nutrient-rich, flavorful, and textural ingredient; however, little is known about their industrial properties. This study evaluated the physicochemical, nutritional, and techno-functional characteristics of PFB varieties: Verde, Quelcao, and Peruanita. PFB exhibited distinct physical characteristics, quality parameters, and morphology. The color patterns of the seed coat and the hardness were the main parameters for distinguishing them. Nutritionally, all three samples exhibited high protein (23.88-24.88 g/100 g), with high proportion of essential amino acids, high dietary fiber (21.74-25.28 g/100 g), and mineral content. They also contain polyphenols (0.79-1.25 mg GAE/g) and flavonoids (0.91-1.06 mg CE/g) with antioxidant potential (16.60-21.01 and 4.68-5.17 µmol TE/g for ABTS and DPPH assays, respectively). Through XRD measurements, the semi-crystalline nature of samples was identified, belonging to the C-type crystalline form. Regarding techno-functionality, PFB flours displayed great foaming capacity, with Verde variety being the most stable. Emulsifying capacity was similar among samples, although Peruanita was more stable during heating. Upon heating with water, PFB flours reached peak viscosities between 175 and 272 cP, and final viscosities between 242 and 384 cP. Quelcao and Verde formed firmer gels after refrigeration. Based on these results, PFB would be useful to developing innovative, nutritious, and healthy products that meet market needs.

Improvement of plant quality by amino acid transporters: A comprehensive review

Amino acids serve as the primary means of transport and organic nitrogen carrier in plants, playing an essential role in plant growth and development. Amino acid transporters (AATs) facilitate the movement of amino acids within plants and have been identified and characterised in a number of species. It has been demonstrated that these amino acid transporters exert an influence on the quality attributes of plants, in addition to their primary function of transporting amino acid transport. This paper presents a summary of the role of AATs in plant quality improvement. This encompasses the enhancement of nitrogen utilization efficiency, root development, tiller number and fruit yield. Concurrently, AATs can bolster the resilience of plants to pests, diseases and abiotic stresses, thereby further enhancing the yield and quality of fruit. AATs exhibit a wide range of substrate specificity, which greatly optimizes the use of pesticides and significantly reduces pesticide residues, and reduces the risk of environmental pollution while increasing the safety of fruit. The discovery of AATs function provides new ideas and ways to cultivate high-quality crop and promote changes in agricultural development, and has great potential in the application of plant quality improvement.

Analysis of Antioxidant Compounds in Vitex negundo Leaves Using Offline 2D-LC-ECD and LC-MS/MS

Vitex negundo has strong antioxidant activity, but its primary antioxidant components are not clear. In this study, the antioxidant components were screened by offline two-dimensional liquid chromatography coupled with electrochemical detection (2D-LC-ECD) and subsequently assessed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) identification, radical scavenging capacity, and molecular docking. Various fractions were isolated from Vitex negundo leaves, and 39 antioxidant components were screened and identified. All of the fractions containing the antioxidant components exhibited certain antioxidant activity. Correlation analysis revealed a strong correlation between the response of LC-ECD and the in vitro antioxidant activity of the fractions. Molecular docking demonstrated that components with high response to LC-ECD exhibited robust interaction with antioxidant-related target proteins. The main antioxidant components of Vitex negundo leaves were isoorientin, chlorogenic acid, agnuside, cynaroside, and scutellarin. The 2D-LC-ECD combined with LC-MS/MS was rapid and effective in screening the antioxidant components in Vitex negundo leaves and could also provide technical support for the discovery of antioxidant components with different polarities and contents in other medicinal and edible plants.

Characterization and discrimination of the taste and aroma of Tibetan Qingke baijiu using electronic tongue, electronic nose and gas chromatography-mass spectrometry

Consumers rely on flavor characteristics to distinguish different types of Qingke Baijiu (QKBJ). Clarifying QKBJ's traits enhances its recognition and long-term growth. Thus, this study analyzed eight QKBJ samples from different regions of Tibet (Lhasa, Sannan, Shigatse, and Qamdo) using GC-MS, electronic nose and electronic tongue. The radar charts of the electronic tongue and electronic nose revealed highly similar profiles for all eight samples. Fifteen common compounds were found in all samples, with the main alcohol compounds being 3-Methyl-1-butanol, 1-hexanol, isobutanol, 1-butanol, 1-nonanol, and phenylethyl alcohol, imparting fruity, floral, and herbal aromas. However, the Sannan samples had higher total alcohol content than total ester content, emphasizing bitterness. Lhasa1 exhibited the most prominent sweetness, Lhasa2 the most noticeable sourness, and Qamdo the most pronounced umami. Lhasa3 and Lhasa4 had total acid content second only to total ester content. Tyd had the highest alkanes, while Lhasa had most aldehydes among samples.

Effects of roasting and steeping on nutrients and physiochemical compounds in organically grown naked barley teas

Barley tea, a popular beverage with cultural traditions in East Asia, has long been esteemed for its flavor, aroma, thirst-quenching properties and perceived health benefits attributed to bioactive compounds. This study investigated the nutritional, bioactive, and antioxidant aspects of three commercial naked barley varieties, focusing on the impact of roasting and subsequent steeping for tea. Roasting did not affect total dietary fiber or β-glucan content. The process reduced sugar content and led to the disappearance of free amino acids, contributing to high levels of acrylamide and color changes. Roasting diminished total phenolic compounds, particularly flavonoids, resulting in reduced antioxidant activity. Metabolite analysis identified compounds in roasted grains that could influence tea flavor and aroma. Roasted barley tea made from these varieties was not a source of dietary fiber or antioxidants, but also contained no acrylamide. Therefore, consumers seeking such benefits from barley are urged to consume whole grain foods.

Unlocking Phenolic Potential: Determining the Optimal Grain Development Stage in Hull-Less Barley Genotypes with Varying Grain Color

Barley is rich in phenolic compounds, providing health benefits and making it a valuable addition to a balanced diet. However, most studies focus on these compounds at barley's final maturity, neglecting their synthesis during grain development and its impact on barley quality for food applications. This study investigates phenolic profiles during grain development in four hull-less barley genotypes with different grain colors, specifically bred for food applications. The objectives were to determine the phenolic profile and identify the optimal maturity stage for maximum phenolic content and antioxidant capacity. Using UPLC-MS/MS and in vitro antioxidant capacity assays, results show that total phenolic compounds decrease as grain matures due to increased synthesis of reserve components. Flavan-3-ols, phenolic acids, and flavone glycosides peaked at immature stages, while anthocyanins peaked at physiological maturity. The harvest stage had the lowest phenolic content, with a gradient from black to yellow, purple, and blue genotypes. Antioxidant capacity fluctuated during maturation, correlating positively with phenolic compounds, specially bound phenolic acids and anthocyanins. These findings suggest that early harvesting of immature grain can help retain bioactive compounds, promoting the use of immature barley grains in foods. To support this market, incentives should offset costs associated with decreased grain weight.

Applications of magnetic solid-phase extraction in the sample preparation of natural product analysis (2020-2023)

Sample preparation, including extraction, separation, and purification, is a vital process for natural product analysis. As an attractive sample pretreatment method, magnetic solid-phase extraction (MSPE) has gained plenty of attention, mainly due to its simpler operation, less consumption of organic solvents, and shorter processing time than traditional SPE. This updated review is devoted to summarizing the applications of MSPE based on different magnetic nanomaterials in the analysis of various natural products in complex matrixes, such as biological samples, plants, and Chinese herbal preparations in the past four years (2020-2023). The preparation and fabrication of different materials are briefly introduced. Furthermore, the extraction mechanism and interaction forces between adsorbent and analytes are elaborated, and the advantages and disadvantages of different adsorbents coupled with various analytical methods for MSPE of different natural products are summarized. Moreover, the future trends and opportunities for MSPE in the natural product analysis are discussed. It is expected that this work can provide updated information for future research on the applications of MSPE in such fields.

Unravelling the metabolomic diversity of pigmented and non-pigmented traditional rice from Tamil Nadu, India

Rice metabolomics is widely used for biomarker research in the fields of pharmacology. As a consequence, characterization of the variations of the pigmented and non-pigmented traditional rice varieties of Tamil Nadu is crucial. These varieties possess fatty acids, sugars, terpenoids, plant sterols, phenols, carotenoids and other compounds that plays a major role in achieving sustainable development goal 2 (SDG 2). Gas-chromatography coupled with mass spectrometry was used to profile complete untargeted metabolomics of Kullkar (red colour) and Milagu Samba (white colour) for the first time and a total of 168 metabolites were identified. The metabolite profiles were subjected to data mining processes, including principal component analysis (PCA), Orthogonal Partial Least Square Discrimination Analysis (OPLS-DA) and Heat map analysis. OPLS-DA identified 144 differential metabolites between the 2 rice groups, variable importance in projection (VIP) ≥ 1 and fold change (FC) ≥ 2 or FC ≤ 0.5. Volcano plot (64 down regulated, 80 up regulated) was used to illustrate the differential metabolites. OPLS-DA predictive model showed good fit (R2X = 0.687) and predictability (Q2 = 0.977). The pathway enrichment analysis revealed the presence of three distinct pathways that were enriched. These findings serve as a foundation for further investigation into the function and nutritional significance of both pigmented and non-pigmented rice grains thereby can achieve the SDG 2.

Transcriptional convergence after repeated duplication of an amino acid transporter gene leads to the independent emergence of the black husk/pericarp trait in barley and rice

The repeated emergence of the same trait (convergent evolution) in distinct species is an interesting phenomenon and manifests visibly the power of natural selection. The underlying genetic mechanisms have important implications to understand how the genome evolves under environmental challenges. In cereal crops, both rice and barley can develop black-coloured husk/pericarp due to melanin accumulation. However, it is unclear if this trait shares a common origin. Here, we fine-mapped the barley HvBlp gene controlling the black husk/pericarp trait and confirmed its function by gene silencing. The result was further supported by a yellow husk/pericarp mutant with deletion of the HvBlp gene, derived from gamma ray radiation of the wild-type W1. HvBlp encodes a putative tyrosine transporter homologous to the black husk gene OsBh4 in rice. Surprisingly, synteny and phylogenetic analyses showed that HvBlp and OsBh4 belonged to different lineages resulted from dispersed and tandem duplications, respectively, suggesting that the black husk/pericarp trait has emerged independently. The dispersed duplication (dated at 21.23 MYA) yielding HvBlp occurred exclusively in the common ancestor of Triticeae. HvBlp and OsBh4 displayed converged transcription in husk/pericarp tissues, contributing to the black husk/pericarp trait. Further transcriptome and metabolome data identified critical candidate genes and metabolites related to melanin production in barley. Taken together, our study described a compelling case of convergent evolution resulted from transcriptional convergence after repeated gene duplication, providing valuable genetic insights into phenotypic evolution. The identification of the black husk/pericarp genes in barley also has great potential in breeding for stress-resilient varieties with higher nutritional values.

Comparison of phenolic composition in Australian-grown date fruit (Phoenix dactylifera L.) seeds from different varieties and ripening stages

In this research, different seeds of Australian-grown date palm (Phoenix dactylifera L.) were studied to evaluate the antioxidant potential and analyze their phenolic constituents. Phenolic compounds were extracted from seeds of various Australian-grown date varieties at different ripening stages. Eight varieties of date seeds (Zahidi, Medjool, Deglet nour, Thoory, Halawi, Barhee, Khadrawy, and Bau Strami) at three ripening stages (Kimri, Khalal, and Tamar) were investigated in this study. Date seeds at Khalal (9.87-16.93 mg GAE/g) and Tamar (9.20-27.87 mg GAE/g) stages showed higher total phenolic content than those at Kimri stage (1.81-5.99 mg GAE/g). For antioxidant assays like DPPH, FRAP, ABTS, RAP, FICA, and TAC, date seeds at Khalal and Tamar stages also showed higher antioxidant potential than Kimri stage. However, date seeds at Kimri stage (55.24-63.26 mg TE/g) expressed higher radical scavenging activity than Khalal (13.58-51.88 mg TE/g) and Tamar (11.06-50.92 mg TE/g) stages. Phenolic compounds were characterized using LC-ESI-QTOF-MS/MS, revealing the presence of 37 different phenolic compounds, including 8 phenolic acids, 18 flavonoids, and 11 other phenolic compounds. Further, phenolic compounds were quantified using LC-DAD, revealing that Zahidi variety of date seeds exhibited the highest content during the Kimri stage. In contrast, during the Khalal and Tamar stages, Deglet nour and Medjool date seeds displayed higher concentrations of phenolic compounds. The results indicated an increase in phenolic content in date seeds after the Kimri stage, with significant variations observed among different date varieties.

Co-culture fermentation by Saccharomycopsis fibuligera and lactic acid bacteria improves bioactivity and aroma profile of wheat bran and the bran-containing Chinese steamed bread

Co-culture fermentation with yeast and lactic acid bacteria (LAB) exhibits advantages in improving the bioactivity and flavor of wheat bran compared to single-culture fermentation, showing application potentials in bran-containing Chinese steamed bread (CSB). To explore the effects of combination of yeast and different LAB on the bioactivity and flavor of fermented wheat bran, this study analyzed the physicochemical properties, phytate degradation capacity, antioxidant activities, and aroma profile of wheat bran treated with co-culture fermentation by Saccharomycopsis fibuligera and eight different species of LAB. Further, the phenolic acid composition, antioxidant activities, texture properties, aroma profile, and sensory quality of CSB containing fermented wheat bran were evaluated. The results revealed that co-culture fermentation brought about three types of volatile characteristics for wheat bran, including ester-feature, alcohol and acid-feature, and phenol-feature, and the representative strain combinations for these characteristics were S. fibuligera with Limosilactobacillus fermentum, Pediococcus pentosaceus, and Latilactobacillus curvatus, respectively. Co-culture fermentation by S. fibuligera and L. fermentum for 36 h promoted acidification with a phytate degradation rate reaching 51.70 %, and improved the production of volatile ethyl esters with a relative content of 58.47 % in wheat bran. Wheat bran treated with co-culture fermentation by S. fibuligera and L. curvatus for 36 h had high relative content of 4-ethylguaiacol at 52.81 %, and exhibited strong antioxidant activities, with ABTS•+ and DPPH• scavenging rates at 65.87 % and 69.41 %, respectively, and ferric reducing antioxidant power (FRAP) at 37.91 μmol/g. In addition, CSB containing wheat bran treated with co-culture fermentation by S. fibuligera and L. fermentum showed a large specific volume, soft texture, and pleasant aroma, and received high sensory scores. CSB containing wheat bran treated with co-culture fermentation by S. fibuligera and L. curvatus, with high contents of 4-ethylguaiacol, 4-vinylguaiacol, ferulic acid, vanillin, syringaldehyde, and protocatechualdehyde, demonstrated strong antioxidant activities. This study is beneficial to the comprehensive utilization of wheat bran resources and provides novel insights into the enhancement of functions and quality for CSB.

Phytochemical analysis, GC-MS characterization and antioxidant activity of Hordeum vulgare seed extracts

Barley scientifically known as Hordeum vulgare (HV) is a major grain crop. Over the course of time, great interest has been developed in the usage of barley, because of its various pharmacological activities. Current study is designed to determine the chemical constituents of Hordeum vulgare (HV) seed extract by GC-MS technique, and Invitro antioxidant assays i.e. 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH) and 2-azino-bis(3-ethyl benzthiazoline-6-sulfonic acid) (ABTS) methods. GC-MS identified 16 non-polar compounds in the hexane extract of HV plant, which includes carboxylic acid (6.25%), fatty acid (37.5%), carboxylic acid amide derivative of fatty acid (6.25%), triterpinoids (18.75%), fat soluble vitamin (6.25%), phytosterol (6.25%), stigmastanes (6.25%), beta diketones (6.25%), and cycloartenol (6.25%) respectively. The major compound includes Hexadecanoic acid, methyl ester (6.84%), n-Hexadecanoic acid (8.58%), 9,12-Octadecanoic acid (Z,Z)-, Methyl Ester (8.04%), 9,12-Octadecadienoic acid (Z,Z) (57.01%), Lup-20(29)-en-3-one (3.57%), γ-Sitosterol (3.31%). Some constituents such as Lup-20(29)-en-3-one, campesterol and squalene were observed and were not previously reported. Total phenolic and total flavonoid content were determined using spectrophotometric technique and calculated as gallic acid equivalents GAE/g dry weight and rutin equivalent RE/g of dry weight respectively.The highest phenolic content exhibited by the acetone extract of HV seedsi.e. 0.0597 mg GAE/g while the highest flavonoid content exhibited by dichloromethane extract i.e. 0.09 mg RE/g and 0.25 mg QE/g of dry weight respectively. All the extracts showed significant antioxidant activity in DPPH and ABTS cation decolorization assays. Methanol and dichloromethane extract showed the highest DPPH radical scavenging activity i.e. 52.41% and 42.07% at the concentration of 100 mg/ml respectively. Moreover, the IC50 has been determined by the acetone and methanol extract of HV seeds. The high antioxidant activity of its seed extracts has made this plant pharmacologically important. Conclusively, there is a vast scope to further explore the active principals of barley so that more of its pharmacological properties can be identified.

Fermentation of Lactobacillus fermentum NB02 with feruloyl esterase production increases the phenolic compounds content and antioxidant properties of oat bran

In this study, strains producing feruloyl esterase were screened by Oxford Cup clear zones method and by evaluating the ability to decompose hydroxycinnamoyl esters. The strain was identified by 16S rDNA molecular biology. The contents of dietary fiber, reducing sugar, water-extractable arabinoxylans, phytic acid, total phenolics, total flavonoid, phenolic compounds composition, microstructure and antioxidant activity in bran before and after fermentation were studied. Eight strains producing feruloyl esterase were screened, among which strain P1 had the strongest ability to decompose hydroxycinnamoyl esters. The strain was identified and named L. fermentum NB02. Compared with unfermented bran, fermented bran exhibited higher contents of soluble dietary fiber, reducing sugar, water-extractable arabinoxylans, total phenolics, total flavonoid, and lower insoluble dietary fiber and phytic acid content. The dense surface structure of bran was destroyed, forming a porous structure. The release of phenolic compounds increased significantly. L. fermentum NB02 fermentation improved the antioxidant capacity of bran.

Insight into the dynamic molecular mechanism underlying the endogenous polyphenols inhibiting the in vitro starch digestion of highland barley noodles

Highland barley is a type of grain with slow-digesting characteristics. It is worth exploring the impact of non-starch components on starch digestion. In this study, four varieties of highland barley were used to investigate the impacts of endogenous polyphenols (EP) on the relationship between starch structure, physicochemical properties, and the time course digestibility of highland barley noodles. The results showed that EP removal decreased the proportion of long-chain amylopectin and disrupted the crystalline structure, while increasing the short-range ordered structure in the residue. Significant correlations indicated that these structural changes make starch more susceptible to thermal degradation and digestion, causing a 12.60%-52.00% increase in rapidly digestible starch (RDS) and a 12.70%-25.22% decrease in resistant starch (RS). These results revealed the internal factors that affect the slow digestion characteristics of highland barley noodles from the perspective of EP and provide important reference values for a slow digestion diet.

Phytochemical Profiling and Biological Activities of Pericarps and Seeds Reveal the Controversy on "Enucleation" or "Nucleus-Retaining" of Cornus officinalis Fruits

The fruits of Cornus officinalis are used not only as a popular health food to tonify the liver and kidney, but also as staple materials to treat dementia and other age-related diseases. The pharmacological function of C. officinalis fruits with or without seeds is controversial for treating some symptoms in a few herbal prescriptions. However, the related metabolite and pharmacological information between its pericarps and seeds are largely deficient. Here, comparative metabolomics analysis between C. officinalis pericarps and seeds were conducted using an ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry, and therapeutic effects were also evaluated using several in vitro bioactivity arrays (antioxidant activity, α-glucosidase and cholinesterase inhibitory activities, and cell inhibitory properties). A total of 499 secondary metabolites were identified. Thereinto, 77 metabolites were determined as key differential metabolites between C. officinalis pericarps and seeds, and the flavonoid biosynthesis pathway was identified as the most significantly different pathway. Further, 47 metabolites were determined as potential bioactive constituents. In summary, C. officinalis seeds, which demonstrated higher contents in total phenolics, stronger in vitro antioxidant activities, better α-glucosidase and butyrylcholinesterase inhibitory activities, and stronger anticancer activities, exhibited considerable potential for food and health fields. This work provided insight into the metabolites and bioactivities of C. officinalis pericarps and seeds, contributing to their precise development and utilization.

pH-Responsive Carrier-Free Polyphenol Nanoparticles Assembled by Oxidative Polymerization with Enhanced Stability and Antioxidant Activity for Improved Bioaccessibility

Encapsulation of plant polyphenols with micro-/nano-carriers for enhanced bioavailability has been well documented, but the preparation of these carriers and subsequent loading of polyphenols is a multiple process, which is generally complicated with potentially unexpected negative effects on the bioactivity of the polyphenols. Here, we reported a convenient method to assemble carrier-free polyphenol nanoparticles (NPs) based on oxidative coupling polymerization. The effectiveness was assessed with five different polyphenols including pyrocatechol (PY), catechin (CA), epigallocatechin gallate (EGCG), tannic acid (TA), and proanthocyanidin (PC). The structural characteristics of these assembled nanoparticles (PY NPs, CA NPs, EG NPs, TA NPs, and PC NPs) were systematically analyzed with dynamic light scattering (DLS), transmission electron microscopy (TEM), UV-visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR). All NPs were colloidally stable with varying NaCl concentrations from 0 to 300 mM, were acid-resistant and alkali-intolerant, and were suitable for oral administration. An array of antioxidant assays further confirmed the superior antioxidant capabilities of NPs over Trolox and polyphenol monomers, indicating that the oxidative polymerization of polyphenols did not compromise the polyphenol activity of NPs. The in vitro simulated digestion studies validated that these responsive NPs were actually gastrointestinal pH-responsive and applicable to the gastrointestinal physiological environment. The bioaccessibility assessments by using a static in vitro digestion model revealed that better results were achieved with NPs than polyphenol monomers, with TA NPs showing about 1.5-fold higher bioaccessibility than other polyphenol nanoparticles. The present study with five polyphenols demonstrated that the oxidative polymerization of polyphenols provides an effective platform to assemble various carrier-free NPs with enhanced antioxidant activity, favorable stability, and improved bioaccessibility, which could be used promisingly as a functional food ingredient in food matrices or as oral drug delivery candidates for helping to manage human health or treating various gastrointestinal disorders in both the pharmaceutical and nutritional fields.

Comparative study on chemical composition, functional properties of dietary fibers prepared from four China cereal brans

Comparison of chemical composition and functional properties of insoluble and soluble dietary fiber (IDF, SDF) obtained from four China cereal brans was investigated. With findings, IDFs and SDFs for rice bran (RB), wheat bran (WB), highland barely bran (HBB) and tartary buckwheat bran (TBB) contained several monosaccharides such as arabinose, galactose, glucose, xylose, and galacturonic acid. The RBIDF was shrinking and formed a rugged microscopic structure, while the structure of WBIDF was dense and flat. HBBIDF and TBBIDF showed fold and flake structure. The glucose adsorption capacity of the HBBIDF was highest among all samples, which was 3.2 mmol/g. TBBIDF exhibited the highest value of cholesterol adsorption capacity (10.5 mg/g) at pH 7.0 and maximum binding capacity (BCmax, 365.2 μmol/g) for cadmium at pH 7.0 among all samples, respectively. As a result, HBBIDF and TBBIDF are potential fiber-rich ingredients in functional foods.

Phenolic Compounds and Antioxidant Capacity Comparison of Wild-Type and Yellow-Leaf gl1 Mutant of Lagerstroemia indica

BACKGROUND

The yellow-leaf gl1 mutant of Lagerstroemia indica exhibits an altered phenylpropanoid metabolism pathway compared to wild-type (WT). However, details on the metabolites associated with leaf color variation, including color-specific metabolites with bioactive constituents, are not fully understood.

METHODS

Chemical and metabolomics approaches were used to compare metabolite composition and antioxidant capacity between the gl1 mutant and WT leaves.

RESULTS

The mutant exhibited an irregular xylem structure with a significantly lower phenolic polymer lignin content and higher soluble phenolic compounds. Untargeted metabolomics analysis identified phenolic compounds, particularly lignans, as key differential metabolites between gl1 and WT, with a significant increase in the mutant. The neolignan derivative balanophonin-4-O-D-glu was identified as a characteristic metabolite in the gl1 mutant. The soluble phenolic compounds of the gl1 mutant exhibited higher FRAP, ABTS, DPPH, and hydroxyl radical scavenging activity than in WT. Correlation analysis showed a positive relationship between antioxidant capacity and phenolic compounds in L. indica.

CONCLUSIONS

Metabolites associated with leaf color variation in the L. indica yellow-leaf gl1 mutant demonstrated high antioxidant capacity, particularly in scavenging hydroxyl radicals.

Metabolomic profiling reveals key factors and associated pathways regulating the differential behavior of rice (Oryza sativa L.) genotypes exposed to geogenic arsenic

Arsenic (As) toxicity is an escalating problem; however, information about the metabolic events controlling the varied pattern of As accumulation in rice genotypes within their natural environment is still lacking. The present study is thus an advancement in unravelling the response of such rice genotypes. Soil-water-rice samples were analyzed for As accumulation using ICP-MS. Furthermore, we implemented metabolomics through LC-MS/MS and UHPLC to identify metabolic signatures regulating As content by observing the metalloid's composition in rice agrosystem. Results showed that rice genotypes differed significantly in their levels of metabolites, with Mini mansoori and Pioneer having the highest levels. Mini mansoori contained least As which might have been regulated by Ala, Ser, Glu, Phe, Asn, His, Ile, Lys, Gln, Trp, Tyr, chlorogenic, p-coumaric, trans-ferulic, rutin, morin, naringenin, kampferol, and myricetin, while Asp, Arg, Met, syringic, epigalocatechin, and apigenin contributed to the greater As acclimatization ability of Pioneer. Multivariate tools separated the rice genotypes into two major clusters: Pioneer-Mini mansoori and Damini-Sampoorna-Chintu. KEGG identified three major metabolic pathways (aminoacyl-tRNA, phenylpropanoid, and secondary metabolites biosynthesis route) linked with As tolerance and adaptation mechanisms in rice. Overall, these two genotypes symbolize their As hostile and accommodating attitudes probably due to the accumulated metabolites and the physicochemical attributes of the soil-water. Thus, thorough understanding of the metabolic reactions to As may facilitate the emergence of As tolerant/resilient genotypes. This will aid in the selection of molecular markers to cultivate healthier rice genotypes in As-contaminated areas.

Effects of unfolding treatment assisted glycation on the IgE/IgG binding capacity and antioxidant activity of ovomucoid

Ovomucoid is the immune-dominant allergen in the egg white of hens. Due to its structure based on nine disulfide bonds as well as its resistance to heat and enzymatic hydrolysis, the allergenicity of this food protein is difficult to decrease by technological processes. We sought to reduce its allergenicity through the Maillard reaction. The unfolding of ovomucoid with L-cysteine-mediated reduction was used to increase accessibility to conformational and linear epitopes by modifying the secondary and tertiary structures of the allergen. Glycation with different saccharides revealed the beneficial effect of maltose glycation on the IgG-binding capacity reduction. By determining the better glycation conditions of unfolded ovomucoid, we produced ovomucoid with reduced IgE binding capacity due to the glycation sites (K17, K112, K129, and K164) on epitopes. Moreover, after simulated infant and adult gastrointestinal digestion, the unfolded plus glycated ovomucoid showed higher ABTS˙+ scavenging activity, O2˙- scavenging activity, ˙OH scavenging activity, Fe2+ chelating activity, and a FRAP value; in particular, for ˙OH scavenging activity, there was a sharp increase of more than 100%.

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.

Targeted metabolic reveals different part of maize in polyphenolic metabolites during germination and hypoglycemic activity analysis

In this study, qualitative and quantitative analyses of phenolic compounds in the maize germinating seed embryo, radicle, and germ were performed at 0, 48, and 96 h post-germination, followed by the evaluation of their hypoglycemic activity. The results revealed the accumulation of 80 phenolics in different parts of germinated maize, of which 47, 48, and 53 were present in the seed embryo, radicle, and germ. After germination 22, 26, and 34 polyphenols were found to differential accumulate in the seed embryo, radicle, and germ. At 96 h post-germination, the content of monomeric phenols in the germ was higher than that in the radicle and seed embryo. Moreover, the inhibitory activity of polyphenols in the germ towards α-glucosidase and α-amylase was higher than that in the radicle and seed embryo. These results indicate that germination can effectively improve the type and content of phenolic compounds in different parts of maize.

Chemoinformatic modelling of the antioxidant activity of phenolic compounds

BACKGROUND

Antioxidants are chemicals used to protect foods from deterioration by neutralizing free radicals and inhibiting the oxidative process. One approach to investigate the antioxidant activity is to develop quantitative structure-activity relationships (QSARs).

RESULTS

A curated database of 165 structurally heterogeneous phenolic compounds with the Trolox equivalent antioxidant capacity (TEAC) was developed. Molecular geometries were optimized by means of the GFN2-xTB semiempirical method and diverse molecular descriptors were obtained afterwards. For model development, V-WSP unsupervised variable reduction was used before performing the genetic algorithms-variable subset selection (GAs-VSS) to construct the best five-descriptor multiple linear regression model. The coefficient of determination and the root mean square error were used to measure the performance in calibration (R²  = 0.789 and RMSEC = 0.381), and test set prediction (Q²  = 0.748 and RMSEP = 0.416), along several cross-validation criteria. To thoroughly understand the TEAC prediction, a fully explained mechanism of action of the descriptors is provided. In addition, the applicability domain of the model defined a theoretical chemical space for reliable predictions of new phenolic compounds.

CONCLUSION

This in silico model conforms to the five principles stated by the Organisation for Economic Co-operation and Development. The model might be useful for virtual screening of the antioxidant chemical space and for identifying the most potent molecules related to an experimental measurement of TEAC activity. In addition, the model could assist chemists working on computer-aided drug design for the synthesis of new targets with improved activity and potential uses in food science. © 2023 Society of Chemical Industry.

Secondary Metabolomic Analysis and In Vitro Bioactivity Evaluation of Stems Provide a Comprehensive Comparison between Dendrobium chrysotoxum and Dendrobium thyrsiflorum

The stems of Dendrobium chrysotoxum (DC) are commonly used as health-promoting foods due to their excellent biological activities. However, the stems of D. thyrsiflorum (DT) are often used to meet the scarcity of DC in production because of their highly similar morphology. However, the related metabolomic and bioactive information on the stems of DC and DT are largely deficient. Here, secondary metabolites of DC and DT stems were identified using an ultra-performance liquid chromatography-electrospray ionization-mass spectrometry, and their health-promoting functions were evaluated using several in vitro arrays. A total of 490 metabolites were identified in two stems, and 274 were significantly different. We screened out 10 key metabolites to discriminate the two species, and 36 metabolites were determined as health-promoting constituents. In summary, DT stems with higher extract yield, higher total phenolics and flavonoids, and stronger in vitro antioxidant activities demonstrated considerable potential in food and health fields.

A Novel Process for One-Step Separation and Cyclodextrin Inclusion of Ginsenoside Rg5 from Ginseng Stem-Leaf Saponins (GSLS): Preparation, Characterization, and Evaluation of Storage Stability and Bioactivity

BACKGROUND

Ginsenoside Rg5 has been proven to possess numerous health benefits. However, Rg5 is difficult to prepare using the current methods, and the poor stability and solubility of Rg5 are intractable properties that limit its application. We try to establish and optimize a new method for preparing Rg5.

METHODS

Different amino acids acted as catalysts, and reaction conditions were investigated to transform Rg5 in GSLS. Different CDs and reaction conditions were investigated for the preparation of CD-Rg5 based on yield and purity; ESI-MS, FT-IR, XRD and SEM analyses were used to prove the formation of the CD-Rg5 inclusion complex. Both the stability and bioactivity of β-CD-Rg5 were investigated.

RESULTS

The content of Rg5 reached 140.8 mg/g after transformation of GSLS using Asp as a catalyst. The yield of β-CD-Rg5 reached a maximum of 12% and a purity of 92.5%. The results showed that the β-CD-Rg5 inclusion complex can improve its stability of Rg5 against light and temperature. Antioxidant activity analyses against DPPH, ABTS⁺, and Fe²⁺ chelation showed enhanced antioxidant activity of the β-CD-Rg5 inclusion complex.

CONCLUSIONS

A novel and effective strategy for the separation of Rg5 from ginseng stem-leaf saponins (GSLS) was developed to improve the stability, solubility, and bioactivity of Rg5.

Classification of Chinese traditional cereal vinegars and antioxidant property predication by fluorescence spectroscopy

In this work, a rapid and accurate strategy for classification of Chinese traditional cereal vinegars (CTCV) and antioxidant property predication was proposed by using the combination fluorescence spectroscopy and machine learning. Three characteristic fluorescent components were extracted by parallel factor analysis (PARAFAC), which have correlations greater than 0.8 with antioxidant activity of CTCV obtained by Pearson correlation analysis. Machine learning methods, including linear discriminant analysis (LDA), partial least squares-discriminant analysis (PLS-DA) and N-way partial least squares discriminant analysis (N-PLS-DA), were used for the classification of different types of CTCV, and the correct classification rates was higher than 97%. The antioxidant property of CTCV were further quantified by using optimized variable-weighted least-squares support vector machine based on particle swarm optimization (PSO-VWLS-SVM). The proposed strategy provides a basis for further research on antioxidant active ingredients and antioxidant mechanisms of CTCV, and enable the continued exploration and application of CTCV from different types.

Modulation of redox-sensitive transcription factors with polyphenols as pathogenetically grounded approach in therapy of systemic inflammatory response

One of the adverse outcomes of acute inflammatory response is progressing to the chronic stage or transforming into an aggressive process, which can develop rapidly and result in the multiple organ dysfunction syndrome. The leading role in this process is played by the Systemic Inflammatory Response that is accompanied by the production of pro- and anti-inflammatory cytokines, acute phase proteins, and reactive oxygen and nitrogen species. The purpose of this review that highlights both the recent reports and the results of the authors' own research is to encourage scientists to develop new approaches to the differentiated therapy of various SIR manifestations (low- and high-grade systemic inflammatory response phenotypes) by modulating redox-sensitive transcription factors with polyphenols and to evaluate the saturation of the pharmaceutical market with appropriate dosage forms tailored for targeted delivery of these compounds. Redox-sensitive transcription factors such as NFκB, STAT3, AP1 and Nrf2 have a leading role in mechanisms of the formation of low- and high-grade systemic inflammatory phenotypes as variants of SIR. These phenotypic variants underlie the pathogenesis of the most dangerous diseases of internal organs, endocrine and nervous systems, surgical pathologies, and post-traumatic disorders. The use of individual chemical compounds of the class of polyphenols, or their combinations can be an effective technology in the therapy of SIR. Administering natural polyphenols in oral dosage forms is very beneficial in the therapy and management of the number of diseases accompanied with low-grade systemic inflammatory phenotype. The therapy of diseases associated with high-grade systemic inflammatory phenotype requires medicinal phenol preparations manufactured for parenteral administration.

Food Service Kitchen Scraps as a Source of Bioactive Phytochemicals: Disposal Survey, Optimized Extraction, Metabolomic Screening and Chemometric Evaluation

Untargeted metabolomics is a powerful tool with high resolution and the capability to characterize a wide range of bioactive natural products from fruit and vegetable by-products (FVB). Thus, this approach was applied in the study to evaluate the phenolic compounds (PC) by metabolomic screening in five FVB after optimizing their extraction. The total phenolic content and antioxidant activity analyses were able to select the best extractor (SM) and ultrasonication time (US) for each FVB; methanol was used as a control. Although ultrasonication yielded a lower number of PC identifications (84 PC), the US extract was the most efficient in total ionic abundance (+21% and +29% compared to the total PC and SM extracts, respectively). Ultrasonication also increased the phenolic acid (+38%) and flavonoid classes (+19%) extracted compared to SM, while the multivariate analyses showed the control as the most dissimilar sample. FVB extracted from the same parts of the vegetable/fruit showed similarities and papaya seed presented the most atypical profile. The application of the metabolomics approach increased the knowledge of the bioactive potential of the evaluated residues and possibilities of exploring and valorizing the generated extracts.

Comprehensive Overview: The Effect of Using Different Solvents for Barley Extraction with Its Anti-Inflammatory and Antioxidant Activity

Barley (Hordeum vulgare L.) is one of the world's oldest cereal crops. There is considerable interest in barley's potential usage in human diets. Barley is rich in bioactive metabolites such as high content of β-glucan, fiber, and vitamin E. It is also well-known as a rich source of phytochemical derivatives, namely, phenolic acids, flavonols, chalcones, flavones, proanthocyanidins, and flavanones. Phenolic compounds are recognized as excellent dietary materials with antioxidant and anti-inflammatory activities. This review was written to give an overview of the main components that are separated from barley using different solvents. Even though there were numerous biological activities for barely, the antioxidant, as well as the anti-inflammatory, are the main focus of this review.

Nutritional Composition and Antioxidant Activity of Gonostegia hirta: An Underexploited, Potentially Edible, Wild Plant

Wild, edible plants have received increasing attention as an important complement to cultivate vegetables, as they represent an easily accessible source of nutrients, mineral elements, and antioxidants. In this study, the tender stems and leaves of Gonostegia hirta, an edible species for which only scarce data are available in the literature, are thoroughly evaluated for their nutritional profile, chemical characterization, and antioxidant activity. Being considered as an underexploited, potentially edible plant, the nutritional composition of Gonostegia hirta was identified, and several beneficial compounds were highlighted: sugars, potassium, calcium, organic acids, fatty acids, phenolics, and flavonoids. A total of 418 compounds were identified by metabolomic analysis, including phenolic acids, flavonoids, amino acids, lipids, organic acids, terpenoids, alkaloids, nucleotides, tannins, lignans, and coumarin. The plant sample was found to have good antioxidant capacities, presented by DPPH, FRAP, ABTS⁺, hydroxyl radical scavenging capacity, and its resistance to the superoxide anion radical test. In general, Gonostegia hirta has a good nutritional and phytochemical composition. The health benefits of Gonostegia hirta as a vegetable and herbal medicine is important for both a modern diet and use in medication.

The variability of phenolic constituents and antioxidant properties among wild populations of Ziziphora clinopodioides Lam

In this study, phenolic derivatives and antioxidant activities of fourteen Ziziphora clinopodioides populations, as well as LC-MS/MS analysis of three specific flavonoids were evaluated. Generally, high contents of phenolic derivatives were found in shoot extracts compared to roots. LC-MS/MS, a powerful analytical technique, was employed for the identification and quantify the individual flavonoids in Z. clinopodioides populations' extracts, in a quantity order of quercetin > rutin > apigenin. Scavenging activity by DPPH and FRAP was performed, and accordingly, in the shoot, the highest values for the DDPH were 4.61 ± 0.4 and 7.59 ± 0.26 µg ml- 1 in populations 1 and 13, respectively, and for the FRAP were 328.61 ± 5.54 and 292.84 ± 2.85 mg g DW- 1, in populations 6 and 1 respectively. Multivariate analysis results of the principal component analysis indicated the amount of polyphenols to be useful indicators in differentiating the geographical localities which explain 92.7% of the total variance. According to the results of hierarchical cluster analysis, the studied populations could be separated into two groups in that the contents of phenolic derivatives and antioxidant activities of different plant parts. Both shoot and root samples were well discriminated with the orthogonal partial least squares discriminant analysis (R2X: 0.861; Q2: 0.47) model. The validity of the model was confirmed by using receiver operating characteristic curve analysis and permutation tests. Such data make an important addition to our current knowledge of Ziziphora chemistry and are decisive in the identification of germplasms with a homogeneous phytochemical profile, high chemical content and bioactivity. The present results could also be helpful for the potential application of Z. clinopodioides in different kinds of industries as natural antioxidants.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12298-023-01283-y.

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.

Comparative analysis of rice reveals insights into the mechanism of colored rice via widely targeted metabolomics

Pigmented rice, particularly black rice, has attracted widespread global interest due to its high nutritional value. To obtain a better understanding of differential metabolites between pigmented rice and white rice, we used a widely-targeted metabolomics-based approach to investigate the metabolite profiling of black, red, glutinous, and common white rice. In total, 732 metabolites were identified, of which 281, 305, 241, 267, and 265 differential metabolites were screened by comparing the following group: glutinous/white vs black, glutinous/white vs red, and red vs black. Venn diagram demonstrated that 69 metabolites were shared between pigmented and non-pigmented rice, and 117 between glutinous/white/red vs black. Additionally, metabolic pathways analysis of differential metabolites in glutinous/white/red vs black revealed that the flavonoid biosynthesis, anthocyanin biosynthesis, and flavone and flavonol biosynthesis are differential enrichment metabolic pathways. As such, identifying these different metabolites contribute to a better understanding of the function and nutritional value of various rice strains.

The phenolics, antioxidant activity and in vitro digestion of pomegranate (Punica granatum L.) peels: an investigation of steam explosion pre-treatment

Pomegranate peels, the main byproduct of pomegranate production, are rich in phenolic compounds that are known for their effective antioxidant properties and have vast application prospects. In this study, steam explosion, an environmentally friendly technique, was applied to pretreat pomegranate peels for phenol extraction. We investigated the effects of explosion pressure, duration, and particle size on the content of total and individual phenolics, and antioxidant activity of pomegranate peels before and after in vitro digestion. The optimal conditions for a steam explosion for pomegranate peels in terms of total phenol content were a pressure of 1.5 MPa, a maintenance time of 90 s, and a particle size of 40 mesh. Under these conditions, pomegranate peel extract presented a higher yield of total phenols, gallic acid, and ellagic acid. However, it also had a lower content of punicalin and punicalagin, compared to the unexploded peels. There was no improvement in the antioxidant activity of pomegranate peels after the steam explosion. Moreover, the content of total phenol, gallic acid, ellagic acid, punicalin, and punicalagin, as well as the antioxidant activity of pomegranate peels, all increased after gastric digestion. Nevertheless, there was a large variation in the pomegranate peel processed by different pressure, duration, and sieve fractions. Overall, this study demonstrated that steam explosion pre-treatment could be an efficient method for improving the release of phenolics, especially gallic acid, and ellagic acid, from pomegranate peels.

Regulatory network characterization of anthocyanin metabolites in purple sweetpotato via joint transcriptomics and metabolomics

INTRODUCTION

Sweet potato is an important staple food crop in the world and contains abundant secondary metabolites in its underground tuberous roots. The large accumulation of several categories of secondary metabolites result in colorful pigmentation of the roots. Anthocyanin, is a typical flavonoid compound present in purple sweet potatoes and it contributes to the antioxidant activity.

METHODS

In this study, we developed joint omics research via by combing the transcriptomic and metabolomic analysis to explore the molecular mechanisms underlying the anthocyanin biosynthesis in purple sweet potato. Four experimental materials with different pigmentation phenotypes, 1143-1 (white root flesh), HS (orange root flesh), Dianziganshu No.88 (DZ88, purple root flesh), and Dianziganshu No.54 (DZ54, dark purple root flesh) were comparably studied.

RESULTS AND DISCUSSION

We identified 38 differentially accumulated pigment metabolites and 1214 differentially expressed genes from a total of 418 metabolites and 50893 genes detected. There were 14 kinds of anthocyanin detected in DZ88 and DZ54, with glycosylated cyanidin and peonidin as the major components. The significantly enhanced expression levels of multiple structural genes involved in the central anthocyanin metabolic network, such as chalcone isomerase (CHI), flavanone 3-hydroxylase (F3H), dihydroflavonol 4-reductase (DFR), anthocyanidin synthase/leucocyanidin oxygenase (ANS), and glutathione S-transferase (GST) were manifested to be the primary reason why the purple sweet potatoes had a much higher accumulation of anthocyanin. Moreover, the competition or redistribution of the intermediate substrates (i.e. dihydrokaempferol and dihydroquercetin) between the downstream production of anthocyanin products and the flavonoid derivatization (i.e. quercetin and kaempferol) under the regulation of the flavonol synthesis (FLS) gene, might play a crucial role in the metabolite flux repartitioning, which further led to the discrepant pigmentary performances in the purple and non-purple materials. Furthermore, the substantial production of chlorogenic acid, another prominent high-value antioxidant, in DZ88 and DZ54 seemed to be an interrelated but independent pathway differentiated from the anthocyanin biosynthesis. Collectively, these data from the transcriptomic and metabolomic analysis of four kinds of sweet potatoes provide insight to understand the molecular mechanisms of the coloring mechanism in purple sweet potatoes.

Modified Highland Barley Regulates Lipid Metabolism and Liver Injury in High Fat and Cholesterol Diet ICR Mice

Highland barley (Hordeum vulgare L. HB) has been demonstrated to have a series of dietotherapy values, including being low fat, low sugar, high fiber, and especially high in β-glucan. Long-term consumption could reduce the incidence of chronic diseases and metabolic syndromes. In this study, the regulating effect of modified highland barley (MHB) products, namely microwave fluidized HB, extruded and puffed HB, and ultrafine pulverized HB on lipid metabolism and liver injury in mice fed a high fat and cholesterol diet (HFCD) was investigated using microbiota diversity gene sequencing and untargeted metabolomics. A total of six groups of mice were supplemented with a normal diet or an HFCD, with or without MHB, and the experimental period lasted 10 weeks. The obtained results demonstrated that MHB supplementation could effectively reverse the increase in body weight gain and adipose tissue accumulation caused by an HFCD (p < 0.05). Moreover, serum biochemical parameters showed that MHB supplementation significantly decreased total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) levels, while increasing high-density lipoprotein cholesterol (HDL-C) levels. The results of hematoxylin and eosin (H&E) assays showed that MHB supplementation could significantly improve the liver injury and adipose tissue accumulation. In addition, 16S rRNA amplicon sequencing showed that MHB supplementation increased the bacteroidetes/firmicutes ratio and the abundance Lactobacillus abundance, while also decreasing the Proteobacteria abundance, which are bacteria closely associated with the hyperlipidemia caused by HFCD. LC-MS metabolomics indicated that MHB supplementation significantly enhanced the levels of Deoxycholic acid, Myclobutanil, 3-Epiecdysone, 3,4-Dihydroxybenzeneacetic acid, and so on. In addition, MHB supplementation promoted activation of the Arachidonic acid metabolism pathways, the expression of ABC transporters, bile secretion, primary bile acid biosynthesis, and so on. Above all, this study showed the potential capacity of MHB to relieve hyperlipidemia and provides a reference for developing a new dietary intervention supplement to ameliorate hyperlipidemia.

Polyphenol Composition and Antioxidant Activity of Japonica Rice Cultivars and Intake Status

Japonica rice is produced mainly in northeast China, Japan, and the Korean Peninsula. Polyphenols and flavonoids are the main antioxidants in japonica rice. This study reported the polyphenol content and antioxidant activity of nine brown and white japonica rice cultivars. The total phenolic and flavonoid contents of brown rice were in the ranges of 241.98-296.76 GAE mg/100 g, and 225.30-276.80 RE mg/100 g, respectively. These values were significantly higher than that of white rice by 118.98-206.06% and 135.0-217%, respectively. The bound fraction from phenolics and flavonoids contributed 41.1-63.6% and 62.22-78.19% of the total phenolic and flavonoid content in brown rice, respectively, while these ranges were 55.5-73.5% and 46.07-66.83% in white rice, respectively. p-Hydroxybenzonic acid was the predominant phenolic acid in japonica rice. All four antioxidant capacities of brown rice (DPPH, ABTS, OH, FRAP) were higher by up to 1.68-2.85 times than those of white rice. The PZ21 (Yanfeng 47) japonica rice variety has outstanding antioxidant capacity based on the weights of each antioxidant index. According to the differences of functional substances among varieties, it can provide guidance for consumers and theoretical basis for the production of healthy food.

Response surface methodology optimization and HPLC-ESI-QTOF-MS/MS analysis on ultrasonic-assisted extraction of phenolic compounds from okra (Abelmoschus esculentus) and their antioxidant activity

Okra (Abelmoschus esculentus) has attracted a growing attention for its nutritional and medicinal values, while few studies focused on systemic study of okra polyphenols (OP). In order to obtain the maximum extracted efficiency, response surface methodology was used to optimize ultrasonic-assisted extraction conditions. The maximum TPC was 7.02 mg GAE/g dw under the condition of solid-liquid ratio 1:25, ethanol concentration 70 %, 40 min, and 142 W at 46 °C. Then 27 compounds in OP were identified by HPLC-ESI-QTOF-MS/MS, among which 7-hydroxycoumarin, scopoletin, luteolin and et al were firstly identified from okra. Furthermore, OP exhibited antioxidant activity in reducing power (FRAP, 9.77 mM Fe²⁺/g OP) and radical scavenging (DPPH, IC₅₀ 19.31 µg/mL; SARC, IC₅₀ 210.81 µg/ml). Moreover, OP significantly inhibited cell apoptosis and ROS generation, and alleviated oxidative damage in t-BHP induced HUVECs. Overall, our findings could provide perspective for further potential employments of okra as functional food.

Top-dressing treatment of spring barley to modify its quality

New barley products can be developed by modifying the content of bioactive components in the grain through breeding, as well as improving its quality at lower fertilizer costs. We aimed to study the effects of the genotype, growth conditions, and top-dressing application of nitrogen and organo-mineral fertilizers on the chemical composition of barley grain. The barley varieties Novichok, Rodnik Prikamya, and Pamyaty Rodinoy were grown under normal (2020) and dry (2021) field conditions. The plants were top-dressed with mineral (CAS; SpetsKhimAgro, Kirovo-Chepetsk, Russia) or organo-mineral (Amino Start and Alfastim; Polydon® Agro, Moscow, Russia) fertilizers in the tillering or heading phases. The contents of protein, starch, fat, and crude fiber in the grain were analyzed with an INFRAMATIC 8620 instrument (Perten Instruments, Stockholm, Sweden). The CAS fertilizer reduced protein, fat, and fiber by 4.5–8.3% (Novichok) during the drought and increased starch by 2.1% (Novichok), fiber by 14.2% (Rodnik Prikamya), and fat by 18.9% (Pamyaty Rodinoy) under normal humidity. Amino Start applied under normal conditions increased starch by 2.9% and reduced protein and fat by 7.8–8.9% in Rodnik Prikamya, as well as increased protein and fat by 14.4 and 6.3%, respectively, but reduced starch by 5.1% in Pamyaty Rodinoy. Alfastim applied under normal conditions reduced the content of protein by 10.7% (Rodnik Prikamya), but increased it by 3.6–7.2% in the other cultivars. It also increased fiber by 22.8% in Rodnik Prikamya, but decreased it by 18.6% in Pamyaty Rodinoy. Finally, this fertilizer decreased fat by 12.7% in Rodnik Prikamya, but increased it by 9.8% in Pamyaty Rodinoy. In the drought, the fertilizers Alfastim and Amino Start increased the protein content by 5.2–12.2% in Rodnik Prikamya and Pamyaty Rodinoy. Top-dressing barley plants with mineral or organo-mineral fertilizers can modify the grain composition (up to 10.4% of fiber, 3.6% of starch, and 7.5% of protein and fat), depending on the consumer’s requirements.