Search Results (62)

Background/Objectives: In this study, the angiotensin-converting enzyme (ACE) inhibitory activity of selected phenolic acids, flavonoids, their O-glucosides, and low-molecular-weight phenolic metabolites was addressed to show their importance against blood hypertension. Methods: A fluorescence assay was used for the determination of the ACE inhibitory activity, whereas the first anodic peak oxidation potential (${\mathrm{E}}_{\mathrm{p}\mathrm{a}}$) was provided by the differential pulse voltammetry (DPV) method. The relationship between the ACE inhibitory activity and ${\mathrm{E}}_{\mathrm{p}\mathrm{a}}$ was evaluated. Results: Phenolic acids showed a very low ACE inhibitory activity, and their rank was chlorogenic acid > p-coumaric acid > sinapic acid > gentisic acid > ferulic acid > syringic acid > vanillic acid > protocatechuic acid > caffeic acid. The low-molecular-weight phenolic metabolites of flavonoids showed a moderate ACE inhibitory activity. In contrast, flavonoid aglicones had the highest ACE inhibitory activity, and the order was luteolin > quercetin > kaempferol > cyanidin > delphinidin > pelargonin > naringenin. A lower inhibition activity was noted for quercetin-3-O-glucoside, luteolin-4′-O-glucosides, cyanidin-3-O-glucoside, and pelargonidin-3-O-glucosides, whereas a higher ACE inhibition activity was observed for 7-O-glucosides of luteolin, apigenin, and kaempferol. A lack of correlation was found between the IC₅₀ of phenolic acids, low-molecular-weight phenolic metabolites, and their ${\mathrm{E}}_{\mathrm{p}\mathrm{a}}$ values. In contrast, weak positive correlations were found between the IC₅₀ of aglicons, 3-O-glucosides, 7-O-glucosides, and their ${\mathrm{E}}_{\mathrm{p}\mathrm{a}}$ values provided by the DPV (r = 0.61, r = 0.66 and r = 0.88, respectively). Conclusions: This study expands our knowledge of the ACE inhibitory activity of phenolic compounds. Full article

Pea (Pisum sativum L.) is a significant source of dietary protein, starch, fiber, and minerals, offering health benefits and serving as both a green vegetable and dry grain. The pigment contents in pea pods with different colors and related genes are still unclear. We conducted an integrated transcriptome and metabolome analysis on three cultivars, including QiZhen (QZ) with green immature pods, FengMi (FM) with yellow immature pods, and ZiYu (ZY) with purple immature pods, to identify the key genes and metabolites involved in anthocyanin accumulation. ZY showed the highest total anthocyanin content compared with FM and QZ. Subsequent quantification revealed that four metabolites, including Delphinidin-3-O-galactoside, Delphinidin-3-O-(6″-O-xylosyl)glucoside, Cyanidin-3-O-galactoside, and Pelargonidin-3-O-(xylosyl)glucoside, were the most highly accumulated in the ZY cultivar, suggesting their role in the purple pigmentation of ZY pea pods. There were 49 differentially accumulated anthocyanidins in ZY vs. FM, 43 differentially accumulated anthocyanidins in ZY vs. QZ, and 21 differentially accumulated anthocyanidins in FM vs. QZ. These findings highlight the importance of the type and concentration of anthocyanin compounds, especially those based on delphinidin, cyanidin, and pelargonidin, in the development of purple pea pods. The transcriptomic analysis revealed that certain anthocyanin biosynthetic genes were expressed at higher levels in ZY than in FM and QZ. In ZY, the higher expression levels of five key genes (PAL, 4CL, CHS, F3H, and UFGT) resulted in elevated anthocyanin content compared to FM and QZ. Furthermore, the BSA-seq analysis identified a candidate region associated with purple color in pea pods, which is located on chromosome 6 and contains 21 DEGs. Sequence variation in KIW84_061698, which encodes a bHLH transcription factor, was identified as the key candidate gene controlling anthocyanin content. This study clarifies the molecular mechanisms behind pea pod coloration and identifies potential genetic engineering targets for breeding anthocyanin-rich sugar snap peas. Full article

Pasta, due to its convenience, follows bread as the most common cereal product in the human diet. Typical wheat pasta is a high-energy product, since it contains a large amount of starch; at the same time, it is characterized by a low content of health-promoting ingredients, such as dietary fiber, minerals, vitamins, and polyphenols. Food industry by-products, or even waste, can be applied as a source of many bioactive substances, thus enriching pasta with bioactive ingredients. Two by-products, Cherry Pomace (CP) and Red Potato Pulp (RPP) were applied as health-promoting supplements for wheat pasta, at three levels (10, 20, and 30%). The antioxidant potential of the resulting pasta was examined (by DPPH, ABTS, FRAP, and FOMO methods), and the antioxidant’s content was also tested. The amount of polyphenols determined by HPLC was higher in the case of CP than in RPP, and the main ones were 5-O-Caffeoylquinic acid and Cyanidin 3-O-rutinoside in CP, whereas for RPP it was Pelargonidin 3-(4‴-p-coumaroylrutinoside)-5-glucoside. Fortified pasta samples were characterized by a higher content of total polyphenols and phenolic acids, flavonoids, flavanols, and anthocyanins. In pasta with a share of CP, some polyphenols were unstable during pasta production. Pasta with a share of CP was characterized by very high antioxidant activity due to a high level of phenolic acids and anthocyanins acting synergistically. It was also characterized by a higher content of phytosterols. A 30% addition of CP into pasta is considered the most beneficial in terms of increasing the health-promoting properties of such a product. Full article

Anthocyanins constitute the primary pigment components in hawthorn (Crataegus pinnatifida) peel, yet their specific composition and concentration profiles remain poorly characterized. This study employed ultra-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (UPLC-ESI-MS/MS)-based metabolomics to systematically compare anthocyanin profiles between red-peel (CPR) and yellow-peel (CPY) hawthorn cultivars. Our analysis identified 26 anthocyanin metabolites in CPR and 24 in CPY, with cyanidin-3-O-galactoside and cyanidin-3-O-arabinoside being the predominant compounds in both. Multivariate analysis revealed seven significantly differential metabolites, including cyanidin-3-O-galactoside, cyanidin-3-O-arabinoside, pelargonidin-3-O-galactoside, pelargonidin-3-O-glucoside, pelargonidin-3-O-arabinoside, and peonidin-3-O-galactoside. Notably, all the differential metabolites exhibited reductions in CPY compared to CPR. Chromatic analysis demonstrated that CPR possessed highly significantly lower hue angle values (h_ab) than CPY (47.7093 ± 4.1706, 83.6427 ± 1.4604, p < 0.01), showing strong negative correlations with key anthocyanins. These findings enhance the scientific understanding of anthocyanin biosynthesis in hawthorn peel and provide a certain reference for the development and utilization of anthocyanins in hawthorn peel. Full article

Flavonoids are secondary metabolites that are beneficial to life activities and are mainly concentrated in buds and leaves in the form of glycosides. Flavonoid glycosides have important effects on the properties and quality of tea plants. Research has shown that the abundance of flavonoid glycosides varies greatly among different cultivars, but research on the regulatory mechanisms that cause their differential accumulation among tea plant cultivars with different leaf colors is lacking. In this study, an integrated analysis of metabolomics and transcriptomics was conducted to determine the regulatory networks regulating astringency and color-related flavonoids in tea plant cultivars with diverse leaf colors. A total of five anthocyanidins, four catechins, and nine flavonol glycosides were found to partially contribute to the differences in taste and leaf color among tea plant cultivars with diverse leaf colors. Furthermore, 15 MYB genes and 5 Dof genes were identified as potential regulators controlling the expression of eight key structural genes, resulting in differences in the accumulation of specific compounds, including epicatechin (EC), catechin (C), cyanidin, cyanidin 3-O-glucoside, pelargonidin 3-O-glucoside, and quercetin 3-O-glucoside, in tea plant cultivars with diverse leaf colors. These findings provide insights into the development and utilization of resources from tea plants with diverse leaf colors. Full article

Strawberries (Fragaria × ananassa) are highly valued for their colorful fruit and flavorful taste. Anthocyanins provide much of the red fruit color, and the flavor is highly affected by soluble sugars and non-volatile organic acids. These fruit composition parameters impact consumer decisions. In this study, strawberry fruits from 17 commercial cultivars and advanced selections were collected weekly from replicated trials at three locations in North Carolina. The relative effects of the location and germplasm on fruit composition were determined, including the soluble solid concentration (SSC), titratable acidity (Tacid), and total anthocyanin content (TAC). The breeding criteria of at least 8.0% SSC and 0.80% Tacid were met by eight and six genotypes, respectively and five of these met both criteria. The fruit TAC ranged from 24.0 to 45.7 mg pelargonidin-3-O-glucoside (P3G) equivalents/100 g FWT. P3G was the dominant pigment in all genotypes, followed by pelargonidin-3-O-rutinoside (P3R). As harvest dates advanced, pH, TAC, P3G, P3R, and pelargonidin-3-O-(6″-malonylglucoside) (P3MG) generally decreased, while Tacid, SSC, and cyanidin-3-O-glucoside (C3G) increased. Composition of field-grown strawberries in this mid-Atlantic location were more influenced by the genotype and harvest date than by the growing location. Full article

This research paper investigates the phytochemical profile, antioxidant activity, antidiabetic potential, and antibacterial activity of Myrtus communis berries. Two extraction methods were employed to obtain the extracts: solid–liquid ultrasound-assisted extraction (UAE) and supercritical fluid extraction (SFE). The extracts were characterized using spectrophotometric methods and Reversed-Phase High-Performance Liquid Chromatography (RP-HPLC). The UAE extract exhibited higher total flavonoid and anthocyanin content, while the SFE extract prevailed in total phenolic content and antioxidant activity in the DPPH radical screening assay. RP-HPLC characterization identified and quantified several polyphenolic compounds. In the UAE extract, epigallocatechin was found in a concentration of 2656.24 ± 28.15 µg/g dry weight (DW). In the SFE extract, cafestol was the identified compound with the highest content at a level of 29.65 ± 0.03 µg/g DW. Both extracts contained several anthocyanin compounds, including cyanidin 3-O-glucoside chloride, cyanidin-3-O-rutinoside chloride, malvidin-3-O-glucoside chloride, pelargonidin 3-O-glucoside chloride, peonidin 3-O-glucoside chloride, and peonidin-3-O-rutinoside chloride. The antidiabetic potential was evaluated in vitro by measuring the inhibition of α-amylase from porcine pancreas (type I-A). The results highlighted the ability of myrtle berry extracts to inhibit α-amylase enzymatic activity, suggesting its potential as an alternative for controlling postprandial hyperglycemia. The UAE extract showed the lowest IC50 value among the two extracts, with an average of 8.37 ± 0.52 µg/mL DW. The antibacterial activity of the extracts was assessed in vitro against Bacillus spp., Escherichia coli, and Staphylococcus aureus using the disk diffusion method. Both myrtle berry extracts exhibited similar antibacterial activity against the tested bacterial strains. The results support further investigation of myrtle berries extracts as a potential ingredient in functional food formulation, particularly due to its antioxidant, antidiabetic, and antibacterial properties. Full article

Marine algae are renowned for their health benefits due to the presence of functional bioactive compounds. In this context, this study aims to valorize the extract of a seaweed, Dictyota dichotoma (D. dichotoma), through phytochemical characterization using liquid chromatography–mass spectrometry (HPLC-MS), as well as in vitro and in silico evaluation of its biological activities (antioxidant and antimicrobial). Phytochemical characterization revealed that the ethanolic extract of Dictyota dichotoma (DdEx) is rich in phenolic compounds, with a total of 22 phycocompounds identified. Antioxidant activity, measured by various methods, showed an IC₅₀ of 120 µg/mL for the DPPH assay, an EC₅₀ of 120.53 µg/mL for the FRAP assay, and a total antioxidant power of 685.26 µg AAE/mg according to the phosphomolybdate (TAC) method. Evaluation of antibacterial activity showed a zone of inhibition diameter ranging from 11.93 to 22.58 mm, with the largest zone observed for the Escherichia coli (E. coli) strain. For antifungal activity, inhibition zone diameters ranged from 22.38 to 23.52 mm, with the largest recorded for the Saccharomyces cerevisiae (S. cerevisiae) strain. The in silico study identified tetragalloyl-glucose, apigenin-7-O-glucoside, and pentagalloyl-glucose as the most active compounds against NADPH oxidase, with docking scores of −7.723, −7.424, and −6.402 kcal/mol, respectively. Regarding antibacterial activity, apigenin-7-O-glucoside, pelargonidin-3-O-glucoside, and secoisolariciresinol demonstrated high affinity for E. coli beta-ketoacyl-[acyl carrier protein] synthase, with docking scores of −7.276, −6.811, and −6.594 kcal/mol, respectively. These in vitro and in silico evaluations showed that D. dichotoma extract possesses antioxidant and antimicrobial properties, due to its richness in bioactive compounds identified by HPLC. Full article

The color variation of the leaves in autumn is a significant ornamental feature of Acer truncatum Bunge, especially when the leaves gradually become redder. Many studies focused on leaf color changes; however, less research has been conducted on the mechanism by which A. truncatum’s autumn leaves turn red. Red, middle and green leaves of Acer truncatum were used as the study materials to evaluate their flavonoid-related metabolites and infer gene and metabolite expression patterns in conjunction with transcriptome expression. For a start, phenotypic and leaf color parameters analyses showed that red leaves had the highest color redness and greenness (a*). In addition, a total of 23 flavonoid-related metabolites were identified through the metabolome, including five anthocyanins. Of them, cyanidin 3-O-β-D-sambubioside, cyanidin 3-O rutinoside, pelargonidin 3-O-3″,6″-O-dimalonylglucoside, delphinidin 3,7-di-O-β-D-glucoside and 3-O-β-D-sambubioside would help the leaves turn red in A. truncatum. Similarly, combined transcriptomics and metabolomics analyses showed that most genes in the flavonoid and anthocyanin biosynthetic pathways were differentially expressed in both types of leaves. Chalcone synthase (CHS), dihydroflavonol 4-reductase (DFR) and anthocyanin synthase (ANS) could affect flavonoid synthesis during leaf color change. This study could provide data for the genetic improvement of maple plants by exploring valuable metabolites and genes in flavonoid synthesis, and enhance the understanding of different developmental stages. Full article

Flower color is one of the most important ornamental traits of chrysanthemums. Previous studies have shown that high temperatures can cause the petals of some chrysanthemum varieties to fade; however, the molecular mechanisms behind this phenomenon remain poorly understood. This study examines the mechanisms of color change in purple chrysanthemums under high-temperature stress using combined metabolomic and transcriptomic analyses. Four chrysanthemum varieties—two heat-stable (‘Zi Feng Che’ and ‘Chrystal Regal’) and two heat-sensitive (‘Zi Hong Tuo Gui’ and ‘Zi Lian’)—were analyzed. High-temperature conditions (35 °C) significantly downregulated key anthocyanins in heat-sensitive varieties, particularly cyanidin-3-O-(3″,6″-O-dimalonyl)glucoside and pelargonidin-3-O-(3″,6″-O-dimalonyl)glucoside. Transcriptome analysis revealed differential gene expression involved in anthocyanin biosynthesis and degradation, with significant enrichment in the MAPK signaling, phenylpropanoid biosynthesis, flavonoid biosynthesis, and anthocyanin biosynthesis pathways. The study highlighted the differential expression of CHS, DFR, ANS, GT1, 3AT, and UGT75C1 genes in anthocyanin synthesis between heat-sensitive and heat-tolerant varieties. Compared to heat-stable varieties, the petals of heat-sensitive varieties exhibited greater differential expression of heat-responsive transcription factors, including HSFs, ERFs, MYBs, and WRKYs. Genes that show a significant negative correlation with the downregulated anthocyanins, including Cse_sc012959.1_g030.1 (βG), Cse_sc001798.1_g020.1 (MYB), Cse_sc006944.1_g010.1 (MYB), and Cse_sc000572.1_g090.1 (HSF), might regulate anthocyanin accumulation in chrysanthemums in response to high-temperature stress. These results provide guidance for the cultivation management and variety selection of chrysanthemums under high-temperature conditions. Additionally, they lay the foundation for elucidating the molecular mechanisms of flower color stability under heat stress and for breeding new heat-tolerant varieties. Full article

Fresh raspberries are highly perishable, but lactic acid bacteria fermentation offers a favourable method for developing healthy products. This study investigated the effects of Lacticaseibacillus paracasei fermentation on the nutrients and phytochemicals of red raspberry nectar using widely targeted metabolomics, as well as its antioxidant activity. The fermentation notably disrupted the raspberry tissue structure, reshaped its non-volatile composition, and increased its DPPH and hydroxyl free radical scavenging abilities. A total of 261 compounds showed significant differences, with 198 upregulated and 63 downregulated. Among these, certain flavonoid glucosides (e.g., pelargonid-in-3-O-rutinoside, delphinidin-3-O-rutinoside-7-O-glucoside, and kaempferol-3-O-glucoside) were significantly downregulated, while some bioactive phenolic acids (e.g., 3-(4-Hydroxyphenyl)-propionic acid and DL-3-phenyllactic acid), alkaloids (e.g., deoxymutaaspergillic acid and indole-3-lactic acid), amino acids (e.g., L-phenylalanine and L-glutamine), and B vitamins (e.g., VB6, VB7, and VB3) were substantially upregulated. Furthermore, the Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation and enrichment analysis revealed that metabolic pathways and the biosynthesis of secondary metabolites contributed significantly to the new profile of fermented red raspberry nectar. These findings provide valuable insights for developing fermented raspberry products using Lacticaseibacillus paracasei, which can help minimise fresh raspberry loss and enhance their valorisation. Full article

In grape (Vitis vinifera L.) cultivation, high temperatures (HTs) usually reduce the accumulation of anthocyanins. In order to elucidate the regulatory mechanism of anthocyanin biosynthesis under high-temperature environments, we investigated the effects of HT stress at veraison (5% coloring of grape ears) on fruit coloration and anthocyanin biosynthesis in ‘Summer Black’ (XH) and ‘Flame seedless’ (FL) grapevines. Compared to the control group (35 °C), the total anthocyanin content of XH and FL grapes subjected to a high-temperature (HT) treatment group (40 °C) decreased significantly as the HT treatment continued, but showed an upward trend with fruit development. However, the concentration of procyanidins increased significantly following HT treatment but decreased with fruit development. Nonetheless, FL grapes showed some resistance to the HT condition, producing anthocyanin content at ripeness comparable to the control group, demonstrating a greater adaptability to HT conditions than XH grapes. Based on the CIRG index, at stage S4, the fruit of FL was classified as dark red, while XH was classified as blue-black in the control group. Anthocyanin-targeted metabonomics identified eight different types of anthocyanins accumulating in the peels of XH and FL grapes during ripening, including cyanidins, delphinidins, malvidins, pelargonidins, peonidins, petunidins, procyanidins, and flavonoids. Malvidins were the most abundant in the two grape varieties, with malvidin-3-O-glucoside being more sensitive to high temperatures. HT treatment also down-regulated the expression of structural genes and regulators involved in the anthocyanin synthesis pathways. We used the WGCNA method to identify two modules that were significantly correlated with total anthocyanin and procyanidin contents. Among them, MYBCS1, bHLH137, WRKY65, WRKY75, MYB113-like, bZIP44, and GST3 were predicted to be involved in grape anthocyanin biosynthesis. In conclusion, this study conducted in-depth research on the HT inhibition of the biosynthesis of anthocyanins in XH and FL grapes, for reference. Full article

The mature flesh of Cornus officinalis exhibits a vibrant red color, attributed to its rich anthocyanin content, imparting significant edible and medicinal value. Vibrant colors not only enhance the visual allure of medicinal materials but also maintain a close association with their intrinsic quality. However, the intricate process of pigment formation governing the anthocyanin accumulation in the pericarp of Cornus officinalis remains poorly understood. In this study, we conducted the comprehensive sampling and analysis of pericarp tissues at three distinct developmental stages, employing morphological-structure observation and metabolomic and transcriptomic techniques. Our findings reveal a substantial increase in the anthocyanin accumulation during the transition to the red stage of Cornus officinalis fruit maturation. Metabolomic profiling identified the highest expression levels of Cyanidin-3-O-glucoside and Pelargonidin-3-O-rutinoside during the mature stage, suggesting their association with the red coloration of the fruit. Through RNA sequencing, we identified 25,740 differentially expressed genes (DEGs), including 41 DEGs associated with anthocyanin biosynthesis. The correlation between the DEG expression levels and anthocyanin content was explored, further elucidating the regulatory network. Additionally, we validated the pivotal role of the candidate gene BZ1 in the synthesis of Cyanidin-3-O-glucoside through qRT-PCR, confirming its crucial impact on anthocyanin accumulation. This study provides preliminary insights into anthocyanin accumulation in Cornus officinalis, laying the foundation for the future development of new cultivars with enhanced anthocyanin contents. Full article

This study aimed to investigate the availability of flavonoids, anthocyanins, and phenolic acids in mutant bean seeds, focusing on M₇ mutant lines, and their corresponding initial and local cultivars. HPLC-DAD-MS/MS and HPLC-MS/MS were used to analyze twenty-eight genotypes of common bean. The obtained results suggest that the mutations resulted in four newly synthesized anthocyanins in the mutant bean seeds, namely, delphinidin 3-O-glucoside, cyanidin 3-O-glucoside, pelargonidin 3-O-glucoside, and petunidin 3-O-glucoside, in 20 accessions with colored seed shapes out of the total of 28. Importantly, the initial cultivar with white seeds, as well as the mutant white seeds, did not contain anthocyanins. The mutant lines were classified into groups based on their colors as novel qualitative characteristics. Five phenolic acids were further quantified: ferulic, p-coumaric, caffeic, sinapic, and traces of chlorogenic acids. Flavonoids were represented by epicatechin, quercetin, and luteolin, and their concentrations in the mutant genotypes were several-fold superior compared to those of the initial cultivar. All mutant lines exhibited higher concentrations of phenolic acids and flavonoids. These findings contribute to the understanding of the genetics and biochemistry of phenolic accumulation and anthocyanin production in common bean seeds, which is relevant to health benefits and might have implications for common bean breeding programs and food security efforts. Full article

Cornus mas L. is a rich source of vitamin C and polyphenols. Due to their health-benefit properties, C. mas L. extracts have been used in, e.g., dermatology and cosmetology, and as a food supplement. Peroxisome proliferator–activated receptor gamma (PPARγ) and its co-activator (PGC-1α) are now suspected to be the main target of active substances from C. mass extracts, especially polyphenols. Moreover, the PPARγ pathway is involved in the development of different diseases, such as type 2 diabetes mellitus (DM2), cancers, skin irritation, and inflammation. Therefore, the aim of the present study was to evaluate the PPARγ pathway activation by the most popular water and ethanol extracts from specific C. mas L. cultivars in an in vitro model of the human normal fibroblast (BJ) cell line. We analyzed the content of biologically active compounds in the extracts using the UPLC-DAD-MS technique and revealed the presence of many polyphenols, including gallic, quinic, protocatechuic, chlorogenic, and ellagic acids as well as iridoids, with loganic acid being the predominant component. In addition, the extracts contained cyanidin 3-O-galactoside, pelargonidin 3-O-glucoside, and quercetin 3-glucuronide. The water–ethanol dark red extract (DRE) showed the strongest antioxidant activity. Cytotoxicity was assessed in a normal skin cell line, and positive effects of all the extracts with concentrations ranging from 10 to 1000 µg/mL on the cells were shown. Our data show that the studied extracts activate the PPARγ/PGC-1α molecular pathway in BJ cells and, through this mechanism, initiate antioxidant response. Moreover, the activation of this molecular pathway may increase insulin sensitivity in DM2 and reduce skin irritation. Full article