Search Results (1,893)

Efficient recovery of phenolic compounds from citrus processing by-products requires optimized solvent systems and reliable frameworks for comparing emerging extraction technologies. In this study, a solvent system was first optimized to maximize phenolic recovery from lemon (Citrus limon (L.) Burm. f.) processing by-products, enabling a standardized comparison of ultrasound-assisted extraction (UAE) and hydrodynamic cavitation (HC). A preliminary solid–liquid extraction screening using different water:ethanol ratios (v/v) identified a 50:50 hydroalcoholic mixture as the optimal solvent system for recovering phenolic compounds. HPLC analysis confirmed the presence of major flavanones (eriocitrin and hesperidin) and hydroxycinnamic acids (caffeic, p-coumaric, sinapic, and ferulic acids). Antioxidant capacity was assessed using complementary assays (Folin–Ciocalteu, DPPH, and ORAC) to provide a comprehensive evaluation of antioxidant activity. Under optimized solvent conditions, UAE significantly improved the recovery of total flavanones (+25.9%), hydroxycinnamic acids (+10.3%), total polyphenols (+20.5%), DPPH activity (+6.0%), and ORAC values (+9.6%) compared with conventional extraction. HC further enhanced extraction performance, increasing flavanone recovery by 12.0%, hydroxycinnamic acids by 7.2%, total polyphenols by 5.2%, and antioxidant activity (DPPH and ORAC) by 11.4% and 2.0%, respectively, relative to UAE. Following ethanol removal and concentration, HC-derived extracts showed the highest phenolic content and antioxidant capacity. These results demonstrate that solvent optimization, combined with a standardized comparison of extraction technologies, enhances phenolic recovery from lemon processing by-products. The findings indicate that HC is a promising, scalable approach for the sustainable recovery of bioactive compounds from citrus side-streams. The novelty of this work lies in the integration of solvent optimization with a systematic and standardized comparison of UAE and HC, providing a reproducible framework for evaluating emerging extraction technologies and highlighting the enhanced performance and scalability potential of HC for phenolic recovery from citrus processing by-products. Full article

Since its discovery in higher plants, melatonin has attracted considerable attention for its antioxidant properties and its diverse roles in plant physiology and stress responses. However, its biosynthetic pathway remains only partially elucidated, particularly in horticultural crops of economic and nutritional importance, such as pepper (Capsicum annuum L.) fruits. In our previous work, we identified five genes encoding tryptophan decarboxylase (TDC), the first enzyme in the melatonin biosynthetic pathway in pepper. The present study expands on this by identifying and characterizing additional genes encoding enzymes involved in subsequent steps of the pathway, including four tryptamine 5-hydroxylase (T5H) genes, two serotonin N-acetyltransferase (SNAT) genes, three N-acetylserotonin O-methyltransferase (ASMT) genes, two caffeic acid O-methyltransferase (COMT) genes, and one N-acetylserotonin deacetylase (ASDAC) gene, representing a total of twelve newly identified genes. We further examined their expression in sweet pepper fruits and found that only nine of the identified genes are expressed in the fruit, with generally higher transcript levels during the unripe stages. Melatonin quantification in the California-type ‘Masami’ cultivar using UPLC with fluorescence detection (FD) revealed concentrations of 623 ng melatonin·g⁻¹ dry weight (DW) in green fruits and 431 ng melatonin·g⁻¹ DW in red fruits, consistent with the higher expression of melatonin biosynthetic genes in unripe fruit. Expression analysis of these genes by means of RNA-seq revealed differential modulation in response to exogenous melatonin treatments (20, 50, and 100 µM). To our knowledge, this is the first report demonstrating that exogenous melatonin regulates the expression of genes involved in its own biosynthetic pathway in sweet pepper fruits. Notably, treatment with 100 µM melatonin delayed ripening in these non-climacteric fruits, highlighting its potential biotechnological application for controlling fruit ripening and improving postharvest management. Full article

The ‘Pingguoli’ pear (Pyrus pyrifolia cv. Pingguoli) has a cultivation history spanning nearly one hundred years. Bud mutation selection is an important breeding method for the ‘Pingguoli’ pear. In this study, high-throughput sequencing technology (RNA-Seq) and non-targeted metabolomics (LC-MS/MS) were used to analyze the large-fruited bud mutation line (LFS) and normal type (NTF) of the ‘Pingguoli’ pear during the cell division (G1), rapid growth (G2), and mature stages (G3) of the fruit. The results showed that LFS exhibited a 46.32% increase in average single fruit weight (383.01 ± 54.72 g vs. 261.76 ± 10.79 g, p < 0.01) and a 19.10% decrease in soluble solids content (12.70 ± 0.94% vs. 15.40 ± 2.06%, p < 0.05) compared to NTF. Compared with the NTF, the content of total phenols and total flavonoids and the activity of antioxidant enzymes in the LFS fruits were significantly higher, while the contents of soluble sugar, reducing sugar, and soluble protein were significantly lower. Transcriptome analysis revealed that key metabolic pathways—including pentose and glucuronate interconversions, starch and sucrose metabolism, and cutin, suberine, and wax biosynthesis—were significantly enriched between NTF and LFS. These pathways may contain the specific differentially expressed genes (e.g., those involved in sugar metabolism and wax biosynthesis) identified as potential regulators of fruit size, appearance, and nutritional quality in the LFS. LC-MS/MS analysis identified key differentially accumulated metabolites, including L-arginine, caffeic acid, L-cysteine, pyridoxamine 5′-phosphate, adenosine-5′-phosphosulfate, neopentolactone D, chlorogenic acid, and gluconic acid, which are directly associated with the nutritional and antioxidant differences between LFS and NTF. The genes most related to metabolites in the three different developmental periods of the LFS and NTF were identified through combined analysis. These results provide insights for further research on bud mutation breeding and the quality formation mechanism of ‘Pingguoli’ pears. Full article

Corn, paddy, wheat, sorghum, and cassava serve as the primary energy sources in both human and animal diets. This study aimed to evaluate their nutrient release patterns in a simulated gastrointestinal environment and to assess the in vitro biological activity of the metabolites produced during digestion. The results showed that wheat exhibited the highest dry matter degradation in the stomach–jejunum–ileum digestion stage, while wheat and paddy showed the highest crude protein degradation compared with the other starch sources. In addition, wheat had a higher total free sugar concentration than paddy, sorghum, and cassava. Among the individual free sugars, such as D-sorbitol and D-(+)-trehalose, were found to have the highest concentrations in wheat, whereas cassava had the highest D(−)-fructose concentration. Several differential metabolites, including valeric acid, caproic acid, octanoic acid, and azelaic acid were highly released in paddy, whereas glucaric acid, threonic acid, phenylacetic acid, and shikimic acid were highly released in cassava, and 4-hydroxycinnamic acid was highly released in paddy and sorghum. Four unique metabolites were identified during the digestion process of five starch sources. Particularly, isocitric acid and trans-cinnamic acid were released only from cassava; caffeic acid was released only from sorghum and corn; and pimelic acid was released only from paddy and wheat. Furthermore, cassava was distinct from the other starch sources, displaying a higher abundance of differential metabolites within the glucagon signaling pathways as mapped in KEGG pathway analysis. In summary, compared with other starch sources, wheat provides more dry matter, protein, and sugars for the body. Cassava is unlikely to offer any advantage in glycemic regulation, while paddy and cassava possess stronger biological activity in terms of differential metabolites. Full article

Meadow arnica is a valuable medicinal plant, used in both the pharmaceutical and cosmetic industries. The aim of the study was to determine the influence of arbuscular mycorrhizal fungi (AMF) on the development, yield, and quality of flower heads (raw material) of meadow arnica grown in an organic farming system. The inoculation of plants with AMF improved the mass of above- and underground organs, including the mass of raw material, as well as the content of chlorophylls and general sugar in the leaves, followed by enhanced starch storage in the roots. The content of phenolics in the raw material was determined using high-performance liquid chromatography (HPLC). The following flavonoids were assessed here: cynaroside, rutin, hyperoside, cosmosiin, astragalin, and diosmetin, as well as the phenolic acids: neochlorogenic, chlorogenic, caffeic, ferulic, rosmarinic, cichoric, 3,4-di-O-caffeoylquinic, and 1,5-dicaffeoylquinic acids. The contents of these substances were higher in non-inoculated plants than in inoculated ones, which contradicts most studies conducted to date on medicinal and aromatic plants. Nevertheless, the results are interesting primarily because of the beneficial developmental changes in inoculated plants, as evidenced by a significantly higher mass of arnica flower heads, more efficient uptake of mineral nutrients from the soil, and lower nitrogen levels in aboveground organs. Full article

The present study provides an exhaustive exploration of twelve macroalgal species from the Adriatic Sea, including seven brown algae (Ericaria amentacea, Fucus virsoides, Cutleria multifida, Cystoseira compressa, Cystoseira corniculata, Gongolaria barbata and Padina pavonica), three green algae (Codium adhaerens, Codium vermilara and Ulva lactuca), and two red algae (Scinaia furcellata and Asparagopsis taxiformis). Matrix solid-phase dispersion (MSPD) was applied as the extraction technique, using generally recognized as safe (GRAS) solvents. The bioactive profile of the extracts was assessed through the quantification of total phenolic content (TPC) and antioxidant activity. Among the three phyla, U. lactuca, F. virsoides and S. furcellata exhibited the highest TPC (0.8, 26 and 3.0 mgGAE·g⁻¹) and antioxidant activity (1.9, 38 and 7.5 mgTE·g⁻¹), respectively. Targeted HPLC-MS/MS analysis enabled the identification of nineteen phenolic compounds across all taxa. Chlorophyta showed a characteristic profile enriched in coumarins, benzaldehydes and flavanones, including the selective detection of 7-hydroxycoumarin in species with higher antioxidant potential. Additionally, compounds such as chlorogenic, rosmarinic and caffeic acids exhibited taxon-specific distributions that may explain differences in antioxidant activity. Complementary untargeted ultra-high performance liquid chromatography quadrupole time-of-flight (UHPLC-QToF) metabolomics analysis provided broader coverage, revealing eighty metabolites spanning phenolics, sugars, organic acids, lipids, amino acids and their derivatives. Notably, the proposed detection of fatty acid esters of hydroxy fatty acids (FAHFAs) represents the first report of these compounds in macroalgae, alongside a pronounced presence of sulphated phenolics. Overall, these findings provide a robust baseline on the bioactivity and chemical composition of Adriatic macroalgae, highlighting their value as a natural source of functional compounds. Full article

Medlar (Mespilus germanica L.) fruit presents a good source of bioactive compounds. This study aimed to optimize the traditional extraction method, maceration, in order to obtain extracts rich in polyphenols. The total phenolic compounds (TPC) from physiologically ripe (PRMFs) and consumable ripe (CRMFs) medlar fruits were extracted to develop models with high accuracy and prediction capacity by response surface methodology (RSM). Furthermore, the main phenolic compounds in the extracts were quantified using HPLC, and the extracts were tested for antioxidant activity and hypoglycemic activity. The extracts were prepared according to a central composite design. The extraction parameters for both PRMFs and CRMFs were time (30–210 min), ethanol concentration (20–80%) and solid-to-solvent ratio (1:10–1:50). The obtained results indicated that the optimal conditions for the extraction were 210 min, 66.55% ethanol, and 1:50 solid-to-solvent ratio (PRMF), and 120 min, 74.96% ethanol, and 1:50 solid-to-solvent ratio (CRMF). Under the optimized conditions, values for TPC were in agreement with the values predicted by RSM. Isoquercitrin, rutin, procyanidin B2, chlorogenic acid and caffeic acid were the most abundant compounds in both PRMF and CRMF optimized extracts. TPC, antioxidant activity, and inhibition of α-glucosidase and α-amylase enzymes did not show significant differences (p > 0.05) among PRMF and CRMF extracts. Full article

Fusarium ear rot (FER), caused by F. verticillioides, is a devastating disease in maize, leading to substantial yield losses and mycotoxin contamination. Therefore, revealing the molecular mechanisms underlying FER resistance is essential for crop breeding. Here, we performed integrated transcriptomic and metabolomic analyses on two maize inbred lines with contrasting FER resistance: the resistant line ZL30-12 (ZL30) and the susceptible line 92C0468U (92C). Following F. verticillioides inoculation, ZL30 exhibited sustained inhibition of fungal colonization and fumonisin accumulation, whereas 92C showed progressive disease development and elevated fumonisin levels. Both transcriptomic and metabolomic analyses converged on the phenylpropanoid pathway, with DEGs enriched in phenylpropanoid metabolism and DAMs enriched in phenylpropanoid biosynthesis, highlighting its central role in resistance. Further integrative analysis revealed that the lignin biosynthetic process, a key branch of phenylpropanoid metabolism, plays an important role in resistance. Several key DEGs (ZmPAL, ZmHCT, peroxidases, and ZmCOMT) and DAMs (sinapic acid, sinapaldehyde, coniferin, cinnamic acid, and caffeic acid) were differentially regulated between the two lines. Correlation analysis revealed a significant correlation between ZmCOMT expression and sinapic acid accumulation. RT-qPCR validation confirmed the expression patterns of key lignin-associated genes. The elevated activation of lignin biosynthesis in ZL30, via time-dependent induction of key genes (ZmPAL, ZmHCT, and peroxidases), suggests an increase in lignin accumulation, which likely reinforces cell wall integrity and restricts fungal invasion, thereby contributing to FER resistance. Collectively, these findings provide insights into the molecular mechanisms of FER resistance and identify key lignin-associated genes as promising targets for maize breeding. Full article

Propolis produced by honeybees, Apis mellifera, has been valued since ancient times as a remedy for different ailments for its broad medicinal properties. This wide range of biological activities may arise from the production of distinct propolis types within the hive, each serving specific functions and containing unique molecular compositions. In this study, we investigated the effects of four propolis types—masonry, sealing, brood-protection, and intruder-neutralizing—on hydrogen peroxide (H₂O₂)-induced oxidative injury in human skeletal muscle cells. Among these, only brood-protection propolis significantly prevented the H₂O₂-induced loss of cell viability. Bio-guided fractionation of this active propolis identified five major compounds: benzyl caffeate (BC), caffeic acid phenethyl ester (CAPE), cinnamyl caffeate (CC), prenyl caffeate (PC), and (E)-3-methyl-3-butenyl caffeate (MBC), all displaying stronger cytoprotective effects than their ferulate equivalents. We finally demonstrated that propolis extract and its active compounds reduced lipid peroxidation in post-mortem minced mouse skeletal muscle and compared their efficacy to other natural compounds. Chemical analysis of resins from neighboring flora suggested that black poplar (Populus nigra) buds are the primary botanical source of these caffeate derivatives. Collectively, these results highlight the functional diversity of hive propolis and its potential applications in food preservation as well as in complementary and preventive medicine. Full article

To further understand redox mechanisms occurring in wine, caffeic acid (CAF, 150 mg/L) and/or glutathione (GSH, 150 mg/L) were added to a model wine solution, followed by ferric iron (2 mg/L Fe(III), added as 10 mg/L Fe(III) chloride hexahydrate), while monitoring the oxidation–reduction potential (ORP, redox potential). Caffeic acid produced only modest ORP changes. In contrast, glutathione and caffeic acid + glutathione additions dropped the ORP from 243 mV and 238 mV, respectively, to the same post-addition value of 189 mV, suggesting that glutathione dictated the ORP, while caffeic acid showed no effect. The quinone of caffeic acid (assumed as changes in AU at 420 nm), was not detected, suggesting caffeic acid did not participate in oxidation reactions under wine conditions under superfluous amounts of dissolved oxygen (DO). After the addition of Fe(III), ORP increased to similar values across all treatments: 266 mV (FE), 269 mV (CAF), 284 mV (GSH), and 242 mV (CAF + GSH), suggesting that the Fe(II)/Fe(III) redox couple dominated the ORP electrode response. CAF + GSH produced the steepest ORP decline after the addition of Fe(III) chloride hexahydrate (β (slope of the ORP) = −0.7082), significantly steeper than FE (β = −0.3051; p = 0.0032) and GSH (β = −0.4643; p = 0.0496), suggesting synergistic radical quenching and metal redox cycling. Photo-Fenton-like reactions likely contributed to slight decreases in the ORP over time. In conclusion, glutathione strongly lowered the ORP, Fe(III) increased the ORP across treatments, and caffeic acid had minimal impact on the ORP under model wine conditions. Full article

The genus Cirsium (family Asteraceae, subfamily Carduoideae) comprises more than 200 species distributed throughout the temperate regions of the Northern Hemisphere. In recent years, particular scientific interest has focused on Cirsium arvense (L.) Scop. (creeping thistle) and Cirsium vulgare (Savi) Ten. (spear thistle). These species are notable for their high content of secondary metabolites and broad biological activity. However, the available data on their phytochemical composition and biological potential remain fragmented. This information is methodologically diverse and scattered across different scientific disciplines, underscoring the need for systematic analysis. In this study, a comprehensive literature review was conducted. Sources included PubMed, Scopus, Web of Science, Google Scholar, and other online databases. The focus was on phytochemical composition and pharmacological activity. Both species contain a wide range of secondary metabolites. These include phenolic acids (chlorogenic, caffeic, and ferulic acids), flavonoids (luteolin, apigenin, kaempferol, quercetin), triterpenoids (lupeol, taraxerol), and phytosterols. C. vulgare generally has higher levels of chlorogenic acid and flavonoid glycosides. In contrast, C. arvense has a greater abundance of triterpenes and steroidal compounds. Pharmacological studies show antioxidant, antimicrobial, hepatoprotective, anti-inflammatory, and cytotoxic activities for both species. Overall, the available data indicate that C. arvense and C. vulgare are promising sources of biologically active compounds with diverse pharmacological potential. Although there are some limitations regarding standardization and the depth of preclinical and clinical validation, the obtained results confirm their relevance for further pharmacological and phytochemical research. Full article

Inflammatory bowel disease (IBD) is a chronic gastrointestinal disorder with a high incidence of anxiety and depression. However, the underlying mechanisms of these symptoms remain to be fully elucidated. This study investigated the effects and mechanisms of a 20% ethanolic extract of Petasites japonicus leaves (EPJ) on dextran sulfate sodium (DSS)-induced colitis and depression-like behaviors. The physiological compounds identified in the EPJ were citric acid, chlorogenic acid, caffeic acid, fukinolic acid, 3,5-dicaffeoylquinic acid, quercetin 3-O-β-D-glucose-6″-acetate, 4,5-dicaffeoylquinic acid, kaempferol-3-O-(6″-acetyl)-β-glucopyranoside, and pedunculoside. EPJ significantly alleviated DSS-induced colitis, as evidenced by improvements in body weight loss (87.41% vs. 76.02% in the DSS group), colon length (5.75 vs. 4.34 cm), intestinal permeability (52.80 vs. 163.01 μg/mL), and myeloperoxidase (MPO) activity (0.24 vs. 0.67 U/mg) (p < 0.05). Histological analysis further confirmed recovery of goblet cells and attenuation of muscle layer thickening. EPJ also reversed DSS-induced gut microbiota dysbiosis and contributed to the restoration of microbial homeostasis. Behavioral assessments showed that EPJ effectively ameliorated depression-like behaviors. EPJ improved antioxidant systems in colon and brain tissues by modulating malondialdehyde (MDA) levels and reduced glutathione (GSH) and superoxide dismutase (SOD) activity. EPJ further upregulated tight junction protein expression and suppressed TLR4/NF-κB inflammatory pathway activation in both colon and brain tissues. Moreover, EPJ modulated serum stress-related hormones, normalized hypothalamic–pituitary–adrenal (HPA) axis dysregulation, regulated the BDNF/TrkB signaling pathway, and modulated tryptophan–kynurenine metabolism. Collectively, these findings suggest that EPJ exerts protective effects against DSS-induced colitis and depression-like behaviors. Full article

Background/Objectives: Obesity represents a critical risk factor for various chronic illnesses and metabolic dysfunctions, underscoring the urgency of identifying safe, food-based interventions to curb fat over-accumulation. Mesona procumbens Hemsl. (Hsian-tsao) is a traditional Chinese herb known for its antioxidant and health-promoting properties; however, it remains unclear how its phenolic acid profiles contribute to anti-obesity activity. This research explored the anti-adipogenic potential of various Hsian-tsao ethanol extracts, focusing on how their phenolic profiles influence lipid suppression in 3T3-L1 adipocytes. Methods: Ethanol extracts prepared using different ethanol concentrations were analyzed for total polyphenol content, antioxidant capacity, and phenolic acid profiles. Adipocytes were exposed to 0, 100, and 250 μg/mL of Hsian-tsao ethanol extract for 48 h duration to monitor changes in cell count and intracellular triglyceride levels. Results: Among all fractions, the 40% ethanol extract (40EEHT) possessed the most robust antioxidant capacity and highest polyphenol content, specifically showing enriched levels of caffeic acid, p-coumaric acid, and total phenolic acids. Notably, while 40EEHT influenced cell density at certain concentrations, it significantly and specifically reduced intracellular triglyceride content, indicating a potent inhibitory effect on lipid storage independent of changes in cell number. Comparative analysis using phenolic acid standards revealed that caffeic acid exerted the strongest inhibitory effect on lipid accumulation, suggesting that it is a key contributor to the anti-adipogenic activity of 40EEHT. Conclusions: Collectively, these findings demonstrate that phenolic acid profiles, particularly caffeic acid enrichment, critically contribute to the potential anti-adipogenic effects of specific ethanol extracts of M. procumbens. Therefore, Hsian-tsao ethanol extracts represent a promising natural source for the development of functional ingredients targeting obesity and related metabolic disorders. Full article

Consumer preference for clean-label products is driving interest in natural antioxidants and antimicrobials that can replace synthetic preservatives. Ziziphus mauritiana (sidr), a resilient desert tree native to the arid Gulf region, has being tested as a multifunctional bio-preservative. This study evaluated the extraction yield, total phenolic content (TPC), total flavonoid content (TFC), antioxidant and antimicrobial activities, and poultry meat-preserving potential of Z. mauritiana. Methanol and ethanol produced the highest extract recoveries, with bark exhibiting the maximum extraction yield of up to 10.7 mg/100 g. Fruits demonstrated the highest total phenolic content (TPC) of around 175 mg gallic acid equivalents per gram (GAE/g) and total flavonoid content (TFC) of around 7.4 mg catechin equivalents per gram (CE/g), followed by leaves and bark. The antioxidant activity was significantly correlated with the concentration of phenolic compounds in the fruit extracts, which exhibited DPPH inhibition exceeding 60% in the majority of instances. The RP-HPLC investigation revealed a diverse polyphenolic profile, predominantly featuring gallic acid (up to 8.77 mg/g in leaves), catechin (6.30 mg/g in fruits), catechol, and caffeic acid. Leaf extracts showed 24 mm inhibitory zones against E. coli and Y. enterocolitica, while bark and fruit were not very effective. Adding ethanolic leaf extract (0–1%) to chicken breast meat reduced microbial degradation during chilled storage at 4 °C. At day 15, total aerobic counts reached only 5.34 log CFU/g with 1% extract compared with 8.53 log CFU/g in the control. Similar suppression was found for yeasts and molds, while challenge tests showed >3-log reductions in C. jejuni and Salmonella senftenberg. Sensory evaluation confirmed no detrimental effects on color, odor, flavor, or texture. Overall, Z. mauritiana was a valuable, renewable source of phenolic antioxidants and antimicrobial agents and showed strong promise as a natural preservative capable of improving the safety and shelf life of poultry meat in clean-label applications. Full article

Phenolic acids are widely known for their antioxidant and biological properties, which make them attractive scaffolds for structural modification. In this short note, we report the synthesis of a new 3,4-di-glucosylated caffeic acid analogue. The (E)-3-(3,4-di-(2,3,4,6-tetra-O-acetyl-β-d-glucopyranosyloxy)phenyl) acrylic acid was obtained through a two-step synthesis, starting with a phase-transfer-catalyzed glycosylation of 3,4-dihydroxybenzaldehyde with 2,3,4,6-tetra-O-acetyl-α-d-glucopyranosyl bromide followed by a Dobner-modified Knoevenagel condensation. Consistent with the 2-O-acetyl neighbouring participation and the resulting Walden-type inversion at the anomeric centre, both glucopyranosyl units were assigned the β-configuration. Full article