Search Results (109)

Polyphenols are known as secondary metabolites, which are crucial bioactive compounds that play a significant role in enhancing human health. Chromatographic methods are typically used to identify polyphenols after food extraction. The extraction methods are fundamental, however, they are implemented with some differences, including extractant type, according to the food. Polyphenols are mostly found in some foods, including grapes, olives, cherries, and apples. Foods have diverse polyphenols, which differ according to the food type. Moreover, they have flavonols, flavanols, flavones, flavanones, isoflavones, and anthocyanins as various subgroups of polyphenols, which can change in terms of quantity and quality along with several factors, including the type, growing region, germination time, and harvest season of the food. The consumption of polyphenols is crucial for human health due to their anti-cancer, anti-tumor, anti-inflammatory, cardiometabolic risk management, antimicrobial, immunomodulatory, and antioxidant effects. In the valorization of polyphenols, the consumption dose is also important to effectively benefit from the polyphenols of plant-based foods. Several in vitro and in vivo studies have tested the polyphenols’ digestion ability and preservation ability in gut microbiota and their effect on the microbiota to determine the benefits and effects of polyphenols in several areas. According to these studies, polyphenols can be used to fight against disease. In addition, diverse applications, including encapsulation and polyphenol coating, are used to stabilize, preserve, and improve the bioaccessibility of polyphenols. Even though polyphenol-rich foods are consumed for nutrition in daily life, they are also used as nutritional ingredients in the food industry to produce functional foods, and functional foods are enriched with food by-products to enhance their nutritional value, especially in terms of polyphenols. Particularly, food by-products are used to enrich functional foods, which are preferred in healthy life diets due to the diversity and amount of bioactive ingredients, including the polyphenol types of the food by-products. Furthermore, polyphenols also provide the preservation ability of storage and improve the bioaccessibility of bioactive ingredients during the digestion of functional foods. This review article examines the polyphenol ingredients of several types of food used in the food industry. It explains the effective factors that affect the amount and type of food and determines the impact of polyphenols on polyphenol-enriched products and functional foods. The article also provides a brief exemplification of the value of polyphenol-rich food by-products in the context of functional food production. Several studies presented in this review article demonstrate the value of polyphenols, particularly in the food industry and functional food production. Full article

In this study, red–blue light (7R3B) was used as the control (CK), while far-red (FR) and ultraviolet-A (UVA) light were supplemented to evaluate their effects on basil growth. The results showed that the FR treatment promoted plant height, stem diameter, and biomass, but reduced chlorophyll and carotenoid content, while the UVA treatment increased stem diameter and chlorophyll b content. Meanwhile, transcriptomic and metabolomic analyses were employed to examine changes in gene expression and metabolite accumulation in basil. The FR treatment reduced the levels of differentially accumulated metabolites (DAMs) in the carotenoid biosynthesis pathway, potentially contributing to the observed decrease in chlorophyll. The FR treatment upregulated the levels of five DAMs (gibberellin, cytokinin, brassinosteroid, jasmonic acid, and salicylic acid) and altered the differentially expressed genes (DEGs) such as gibberellin receptor (GID1) and jasmonate ZIM domain-containing protein (JAZ) in the plant hormone signal transduction pathway, thereby promoting plant growth and shade avoidance responses. The UVA treatment upregulated the 9-cis-epoxycarotenoid dioxygenase (NCED) expression in the carotenoid biosynthesis pathway, possibly indirectly promoting flavonoid synthesis. In the flavonoid biosynthesis pathway, the UVA treatment also promoted flavonoid accumulation by upregulating DEGs including flavonol synthase (FLS), anthocyanidin synthase (ANS), 5-O-(4-coumaroyl)-D-quinate 3′-monooxygenase (CYP98A), and flavanone 7-O-glucoside 2″-O-beta-L-rhamnosyltransferase (C12RT1), as well as increasing the levels of DAMs such as kaempferol, luteolin, apigenin, and leucopelargonidin. The accumulation of flavonoids improved antioxidant capacity and nutritional value in basil. Through a Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, this study provided valuable insights into the molecular and metabolic mechanisms of the FR and UVA regulation of basil growth, providing guidance for optimizing supplementary lighting strategies in plant factories. Full article

Banana is a commercially important crop widely cultivated in tropical and subtropical regions, but its cultivation in the canal command basins is challenged due to the development of waterlogged sodic soils. The present study aimed to induce sodicity tolerance through the integration of secondary metabolites in the plants during the tissue culture organogenesis phase. Secondary-metabolite-treated plants were assessed for their performance in the waterlogged sodic soil areas of Samesee block in Lucknow district of Uttar Pradesh, India. Metabolite-treated (MT) plants exhibited significantly better growth and yield compared to untreated control (UTC) plants. Key physiological enhancements in MT plants included increased activities of defense-related enzymes superoxide dismutase (SOD), phenylalanine ammonia lyase (PAL), peroxidase (POD), and proline along with a reduced Na⁺/K⁺ ratio. The metabolic profile of MT plants showed higher expression of antioxidants, phenolic compounds, and flavonoids. MT plants exhibited production of the metabolites such as trihydroxy methylene–di-oxyflavone, rush flavanone, rutin, anthocyanins, neodiosmin, arachidonic acid, and trigalloyl-HHDP-glucose, which belongs to the subclasses of flavonoids, anthocyanins, and sugar alcohols. Consequently, MT plants produced a significantly higher yield (20.85 kg per plant) compared to UTC plants (8.35 kg) and greater biomass. These results suggest that treatments using secondary metabolite extracted from salt-tolerant bacteria can be used as an effective strategy for enhancing sodicity tolerance in banana plants, contributing to sustainable production and economic viability in waterlogged sodic soil conditions. Full article

Drought stress significantly impairs the output of tea plants and the quality of tea products. Although Serendipita indica has demonstrated the ability to enhance drought tolerance in host plants, its impact on tea plants (Camellia sinensis) experiencing drought stress is unknown. This study assessed the response of tea plants by inoculating S. indica under drought conditions. Phenotypic and physiological analyses demonstrated that S. indica mitigated drought damage in tea plants by regulating osmotic equilibrium and antioxidant enzyme activity. Metabolome analysis showed that S. indica promoted the accumulation of flavonoid metabolites, including naringin, (-)-epiafzelechin, naringenin chalcone, and dihydromyricetin, while inhibiting the content of amino acids and derivatives, such as homoarginine, L-arginine, N6-acetyl-L-lysine, and N-palmitoylglycine, during water deficit. The expression patterns of S. indica-stimulated genes were investigated using transcriptome analysis. S. indica-induced drought-responsive genes involved in osmotic regulation, antioxidant protection, transcription factors, and signaling were identified and recognized as possibly significant in S. indica-mediated drought tolerance in tea plants. Particularly, the flavonoid biosynthesis pathway was identified from the metabolomic and transcriptomic analysis using Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Moreover, flavonoid biosynthesis-related genes were identified. S. indica-inoculation significantly upregulated the expression of cinnamate 4-hydroxylase (C4H), chalcone synthase (CHS), flavanone 3-hydroxylase (F3H), dihydroflavonol 4-reductase (DFR), anthocyanidin reductase (ANR), and leucoanthocyanidin reductase (LAR) genes compared to uninoculated plants subjected to water stress. Consequently, we concluded that S. indica inoculation primarily alleviates drought stress in tea plants by modulating the flavonoid biosynthesis pathway. These results will provide insights into the mechanisms of S. indica-enhanced drought tolerance in tea plants and establish a solid foundation for its application as a microbial agent in the management of drought in tea plants cultivation. Full article

Many aromatic herbs are conventionally used for flavoring various foods, but receive wide attention because of the variety of health-related properties. The aromatic herbs can be used either fresh or as dried powders and in the form of extracts, essential oils, or purified metabolites. In this review, the main functional properties, in terms of antioxidant and antimicrobial properties, and the applications of some of the commonly used aromatic herbs from the Lamiaceae family, are discussed. Herbs like oregano, rosemary, sage, thyme, summer savory, marjoram, and basil possess high levels of bioactive phytochemicals. They are particularly rich in phenolic acids, flavones, phenolic diterpenes, and flavanones, with various beneficial effects. The phytochemical profile of aromatic plants is highly influenced by genetic factors, environmental conditions, and their interaction. In cases of the extracts and essential oils, the extraction method has a strong effect on the final composition of the herb products. Most of the applications of these aromatic herbs are related to their antioxidant, antimicrobial, and flavoring properties. In particular, aromatic herb extracts and essential oils have multiple applications in fields like food, feed, pharmaceutical, cosmetics, biopesticides, and textile industries. Full article

Callus browning is a significant problem that hinders plant tissue regeneration in Paeonia ostii “Fengdan” by causing cell death and inhibiting growth. However, the molecular mechanism underlying callus browning in P. ostii remains unclear. In this study, we investigated the metabolites and potential regulatory genes involved in callus browning of P. ostii using metabolomic and transcriptomic analyses. We found a significant accumulation of phenolic compounds in the browned callus, represented by flavonoid compounds. Notably, the accumulations of luteotin and disomentin were higher in browning calli compared to non-browning calli. Transcriptomic analysis identified that candidate genes associated with flavonoid biosynthesis, including flavonoid 3-hydroxylase (PoF3H) and flavone synthase II (PoFNSII), were highly expressed in the browned callus of P. ostii “Fengdan”. Weighted gene co-expression network analysis (WGCNA) further highlighted that polyphenol oxidase (PoPPO) which encoded polyphenol oxidase, together with flavonoid biosynthesis-related genes such as flavanone 3-hydroxylase (PoF3H) and flavonone Synthase II (PoFNSII), as well as cellular totipotency-related genes wuschel-related homeobox 4 (PoWOX4), were involved in callus browning. Based on these findings, we proposed the molecular mechanism by which flavonoid accumulation, polyphenol oxidation, and cellular totipotency pathways contribute to callus browning in P. ostii. Our study provides new insights into the molecular mechanism underlying callus browning and offers the foundations to facilitate the establishment of an efficient plant tissue regeneration system in P. ostii. Full article

Background/Objectives: The germination process initiates an active process of secondary metabolism, which produces a series of secondary metabolites, including flavonoids. Methods: A metabolomics and transcriptomics analysis was conducted on maize grains germinated at three different stages. Results: A total of 374 metabolites were detected in maize grains. From the raw maize grain to various stages of germination, 3 anthocyanins, 61 flavones, 12 flavonols, 13 flavanones, and 6 isoflavones were identified, respectively. An integrated omics analysis discovered that a total of 16 flavonoid metabolites were mapped to 4 KEGG pathways, which were associated with 40 related genes. This indicates that germination has significant benefits in improving the nutritional function of corn kernels. Conclusions: In summary, the findings of this study provide valuable insights into flavonoid metabolites and related genes, demonstrating the profound impact of germination treatment on the nutritional and functional aspects of maize grains. Full article

Phenolic compounds, such as stilbenes and flavonoids, from Dalea spp. exhibit diverse biological activities, including antimicrobial, anti-inflammatory, and cytotoxicity properties. To this end, the objectives of this study were to establish hairy root cultures of D. purpurea and assess its capacity to produce these bioactive compounds. The co-treatment of the hairy root cultures with the elicitors methyl-β-cyclodextrin, magnesium chloride, methyl jasmonate, and hydrogen peroxide led to the production and secretion of the geranylated flavanone malheuran A, which was confirmed by mass spectrometry and NMR spectroscopy analyses. The highest amount (104.3 ± 6.9 mg/L) of malheuran A was detected at 192 h after elicitor treatment. The elicited hairy roots were re-elicited for 192 h with the same combination of elicitors, and they produced a substantial amount of malheuran A (91.9 ± 6.8 mg/L). Malheuran A, purified from extracts of the hairy root culture medium, showed potent antimicrobial activity against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci. It also demonstrated anti-inflammatory effects by suppressing nitrite production in LPS-stimulated RAW 264.7 macrophages. These findings show that various elicitor treatments can boost malheuran A production in hairy root cultures, making them a sustainable bioproduction platform for this bioactive specialized metabolite. Full article

Djulis (Chenopodium formosanum Koidz.), a member of the Amaranthaceae family plant, is noted for its vibrant appearance and significant ornamental value. However, the mechanisms underlying color variation in its spikes remain unexplored. This research initially detected the anthocyanin content at different developmental stages of the spike and subsequently utilized an integrative approach, combining targeted metabolomics, transcriptomics, and untargeted metabolomics analyses, to elucidate the mechanisms of anthocyanin biosynthesis in the spikes of djulis. The results of the combined multi-omics analysis showed that the metabolites associated with anthocyanin synthesis were mainly enriched in the flavonoid biosynthesis pathway (ko00941) and the anthocyanin biosynthesis pathway (ko00942). With the maturation of djulis spikes, a total of 28 differentially expressed genes and 17 differentially expressed metabolites were screened during the transition of spike color from green (G) to red (R) or orange (O). Twenty differentially expressed genes were selected for qRT-PCR validation, and the results are consistent with transcriptome sequencing. The upregulation of seven genes, including chalcone synthase (CfCHS3_1, CfCHS3_2, CfCHS3_3), flavanone 3-hydroxylase (CfF3H_3), flavonoid 3′5′-hydroxylase (CfCYP75A6_1), dihydroflavonol reductase (CfDFRA), and glucosyltransferase (Cf3GGT), promotes the formation and accumulation of delphinidin 3-sambubioside and peonidin 3-galactoside. The research results also showed that anthocyanins and betalains can coexist in the spike of djulis, and the reason for the change in spike color during development may be the result of the combined action of the two pigments. A possible regulatory pathway for anthocyanin biosynthesis during the spike maturation was constructed based on the analysis results. The results provide a reference and theoretical basis for further studying the molecular mechanism of anthocyanin regulation of color changes in Amaranthaceae plants. Full article

Pentadesma butyracea is a medicinal plant of which bark decoctions are used in traditional medicine for the treatment of diarrhea symptoms in Gabon. The aim of the present work was to perform phytochemical and pharmacological analyses of decoctions of P. butyracea bark. In a principal approach, spectrophotometric analyses were used to quantify phenolic compounds, followed by liquid chromatography coupled to mass spectrometry analysis that allowed the identification of flavanone–flavone dimers as the main metabolites. Pharmacological analyses showed the absence of toxicity, thus confirming the safety of use of this decoction in traditional medicine. The antioxidant activity of the bark decoctions was demonstrated to depend on their phenolic contents. The decoction of stem barks harvested during the rainy season also induced a dose-dependent relaxation of isolated ileum fragments from Wistar rats. In addition, the antidiarrheal activity of P. butyracea barks was investigated against castor oil-induced diarrhea. The oral administration of different concentrations of this decoction led to a decrease in wet stools, indicating an antidiarrheal effect at the doses that were used. These results encourage the deepening of bio-guided research on P. butyracea bark decoctions in order to propose standard traditional medical treatments. Full article

Camellia hainanica is one of the camellia plants distributed in tropical regions, and its regeneration system and genetic transformation are affected by callus browning. However, the underlying mechanism of Camellia hainanica callus browning formation remains largely unknown. To investigate the metabolic basis and molecular mechanism of the callus browning of Camellia hainanica, histological staining, high-throughput metabolomics, and transcriptomic assays were performed on calli with different browning degrees (T1, T2, and T3). The results of histological staining revealed that the brown callus cells had obvious lignification and accumulation of polyphenols. Widely targeted metabolomics revealed 1190 differentially accumulated metabolites (DAMs), with 53 DAMs annotated as phenylpropanoids and flavonoids. Comparative transcriptomics revealed differentially expressed genes (DEGs) of the T2 vs. T1 associated with the biosynthesis and regulation of flavonoids and transcription factors in Camellia hainanica. Among them, forty-four enzyme genes associated with flavonoid biosynthesis were identified, including phenylalaninase (PAL), 4-coumaroyl CoA ligase (4CL), naringenin via flavanone 3-hydroxylase (F3H), flavonol synthase (FLS), Chalcone synthase (CHS), Chalcone isomerase (CHI), hydroxycinnamoyl-CoA shikimate transferase (HCT), Dihydroflavonol reductase (DFR), anthocyanin reductase (LAR), anthocyanin synthetase (ANS), and anthocyanin reductase (ANR). Related transcription factors R2R3-MYB, basic helix-loop-helix (bHLH), and WRKY genes also presented different expression patterns in T2 vs. T1. These results indicate that the browning of calli in Camellia hainanica is regulated at both the transcriptional and metabolic levels. The oxidation of flavonoids and the regulation of related structural genes and transcription factors are crucial decisive factors. This study preliminarily revealed the molecular mechanism of the browning of the callus of Camellia hainanensis, and the results can provide a reference for the anti-browning culture of Camellia hainanica callus. Full article

To reveal the effect of sucrose concentration on the production of secondary metabolites, a metabolome and transcriptome joint analysis was carried out using callus induced from grape variety Mio Red cambial meristematic cells. We identified 559 metabolites—mainly flavonoids, phenolic acids, and stilbenoids—as differential content metabolites (fold change ≥2 or ≤0.5) in at least one pairwise comparison of treatments with 7.5, 15, or 30 g/L sucrose in the growing media for 15 or 30 days (d). Resveratrol, viniferin, and amurensin contents were highest at 15 d of subculture; piceid, ampelopsin, and pterostilbene had higher contents at 30 d. A transcriptome analysis identified 1310 and 498 (at 15 d) and 1696 and 2211 (at 30 d) differentially expressed genes (DEGs; log2(fold change) ≥ 1, p < 0.05) in 7.5 vs. 15 g/L and 15 vs. 30 g/L sucrose treatments, respectively. In phenylpropane and isoflavone pathways, DEGs encoding cinnamic acid 4-hydroxylase, chalcone synthase, chalcone isomerase, and flavanone 3-hydroxylase were more highly expressed at 15 d than at 30 d, while other DEGs showed different regulation patterns corresponding to sucrose concentrations and cultivation times. For all three sucrose concentrations, the stilbene synthase (STS) gene exhibited significantly higher expression at 15 vs. 30 d, while two resveratrol O-methyltransferase (ROMT) genes related to pterostilbene synthesis showed significantly higher expression at 30 vs. 15 d. In addition, a total of 481 DEGs were annotated as transcription factors in pairwise comparisons; an integrative analysis suggested MYB59, WRKY20, and MADS8 as potential regulators responding to sucrose levels in flavonoid and stilbene biosynthesis in grape callus. Our results provide valuable information for high-efficiency production of flavonoids and stilbenes using grape callus. Full article

Pelargonium graveolens L’Hèr. (Geraniaceae) is renowned for its traditional use as a flavor, ornamental and medicinal plant. This work aimed at an in-depth study of the phytochemical profiling and in vitro antioxidant and enzyme inhibition assessment of a methanol-aqueous extract from P. graveolens leaves. A UHPLC-HRMS analysis revealed more than 110 secondary metabolites, including 8 acyltartaric and 11 acylcitric/acylisocitric acids; 8 gallotannins; 36 flavonols, flavanones and methoxylated flavonoids together with 17 phenolic and aliphatic acids; and 21 phenolic acid glycosides. For the first time, acylcitric acids along with feruloyl- and coumaroyltartaric acids are reported in the species. The leaf extract actively scavenged 2,2-diphenyl-1-picrylhydrazyl DPPH (273.45 mg trolox equivalent (TE/g)) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS^•+) radicals (531.97 mgTE/g) and showed a high reducing power: 431.32 mg TE/g Cupric reducing antioxidant capacity (CUPRAC) and 292.21 mg TE/g Ferric reducing antioxidant power (FRAP). It possessed a metal chelating capacity (13.44 ethylenediaminetetraacetic acid equivalent (EDTAE)/g) and contained 2.71 mmol TE/g in the phosphomolybdenum assay. The rose geranium extract exhibited high inhibition towards acetyl- and butyrylcholinesterase (2.80 and 2.20 mg galantamine equivalent (GALAE)/g, respectively) and tyrosinase (75.49 mg kojic acid equivalent (KAE)/g). It inhibited α-glucosidase and α-amylase (3.75 mmol and 0.79 acarbose equivalent (ACAE)/g, respectively) and lipase (28.91 mg orlistat equivalent (OE)/g). This study sheds light into the future potential application of the rose geranium in pharmaceutical and nutraceutical products. Full article

Cyanobacteria are rich producers of secondary metabolites, excreting some of these to the culture media. However, the exometabolome of cyanobacteria has been poorly studied, and few studies have dwelled on its characterization and bioactivity assessment. In this work, exometabolomes of 56 cyanobacterial strains were characterized by HR-ESI-LC-MS/MS. Cytotoxicity was assessed on two carcinoma cell lines, HepG2 and HCT116, while the reduction in lipids was tested in zebrafish larvae and in a steatosis model with fatty acid-overloaded human liver cells. The exometabolome analysis using GNPS revealed many complex clusters of unique compounds in several strains, with no identifications in public databases. Three strains reduced viability in HCT116 cells, namely Tolypotrichaceae BACA0428 (30.45%), Aphanizomenonaceae BACA0025 (40.84%), and Microchaetaceae BACA0110 (46.61%). Lipid reduction in zebrafish larvae was only observed by exposure to Dulcicalothrix sp. BACA0344 (60%). The feature-based molecular network shows that this bioactivity was highly correlated with two flavanones, a compound class described in the literature to have lipid reduction activity. The exometabolome characterization of cyanobacteria strains revealed a high chemodiversity, which supports it as a source for novel bioactive compounds, despite most of the time being overlooked. Full article

Sunburn stress is one of the main environmental stress factors that seriously affects the fruit development and quality of Chinese olive, a tropical and subtropical fruit in south China. Therefore, the understanding of the changes in physiological, biochemical, metabolic, and gene expression in response to sunburn stress is of great significance for the industry and breeding of Chinese olive. In this study, the different stress degrees of Chinese olive fruits, including serious sunburn injury (SSI), mild sunburn injury (MSI), and ordinary (control check, CK) samples, were used to identify the physiological and biochemical changes and explore the differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) by using transcriptomics and metabolomics. Compared with CK, the phenotypes, antioxidant capacity, and antioxidant-related enzyme activities of sunburn stress samples changed significantly. Based on DEG-based KEGG metabolic pathway analysis of transcriptomics, the polyphenol and flavonoid-related pathways, including phenylpropanoid biosynthesis, sesquiterpenoid, and triterpenoid biosynthesis, monoterpene biosynthesis, carotenoid biosynthesis, isoflavonoid biosynthesis, flavonoid biosynthesis, were enriched under sunburn stress of Chinese olive. Meanwhile, 33 differentially accumulated polyphenols and 99 differentially accumulated flavonoids were identified using metabolomics. According to the integration of transcriptome and metabolome, 15 and 8 DEGs were predicted to regulate polyphenol and flavonoid biosynthesis in Chinese olive, including 4-coumarate-CoA ligase (4CL), cinnamoyl-CoA reductase (CCR), cinnamoyl-alcohol dehydrogenase (CAD), chalcone synthase (CHS), flavanone-3-hydroxylase (F3H), dihydroflavonol 4-reductase (DFR), and anthocyanidin synthase (ANS). Additionally, the content of total polyphenols and flavonoids was found to be significantly increased in MSI and SSI samples compared with CK. Our research suggested that the sunburn stress probably activates the transcription of the structural genes involved in polyphenol and flavonoid biosynthesis in Chinese olive fruits to affect the antioxidant capacity and increase the accumulation of polyphenols and flavonoids, thereby responding to this abiotic stress. Full article