Search Results (596)

Rhododendron adamsii Rehder, also known as sagan dali, is one of the most valued northern rhododendron species of Siberia and Mongolia as both a medicinal and food plant. Its flowers are traditionally used by indigenous communities in daily life to prepare teas that are attributed with medicinal properties in local traditional medicine. However, the lack of reliable data on the chemical composition and bioactivity of R. adamsii flowers has limited their broader application and underscores the need for comprehensive studies to verify their beneficial properties. The application of liquid chromatography–mass spectrometry enabled the identification of fifty-four compounds in sixteen samples of different origins, with flavonoids representing the dominant group and belonging to various aglycone types. Among the identified metabolites were dihydroflavonols of the taxifolin series; flavonols of the myricetin, quercetin, and kaempferol series; as well as several minor flavonoid and non-flavonoid compounds. Thirty-seven of these compounds are reported for the first time in this species. The total phenolic content in R. adamsii flowers can reach 155.82 mg/g, of which up to 147.54 mg/g are flavonoids. The analysis revealed variation in both the qualitative profile and quantitative levels of individual compounds among different populations, suggesting the presence of distinct R. adamsii chemotypes. The preparation of flower tea was associated with high rates of flavonoid transfer into the decoction, particularly when pulverized raw material was used compared with unground or hand-ground samples. This was reflected in the enhanced antioxidant activity of the decoctions, which was maximal for pulverized flowers in in vitro assays against artificial and natural free radicals, as well as in nitric oxide scavenging and Fe²⁺-chelating tests. These results suggest that R. adamsii flowers and their tea represent a new possible source of flavonoids and after additional clinical evidence may serve as valuable antioxidant ingredients for the development of functional foods. Full article

This study compared the quality and bioactive composition of cloudy apple juices produced from four traditional and four conventional apple cultivars immediately after harvest and following cold storage of the fruit at 4 °C for three and six months. Apples were harvested at the ripening stage at the same criteria, stored as whole fruit, and processed into cloudy juice after harvest, three, and six months of storage. Physicochemical parameters and sugar composition were determined, while phenolic compounds were quantified by HPLC-PDA. Antioxidant activity, total phenolic, and flavonoid content were measured spectrophotometrically. All analyses were performed in technical triplicate. The results revealed notable differences between traditional and conventional cultivars. Juices produced from traditional apple cultivars exhibited significantly higher total polyphenol and flavonoid contents than those from conventional cultivars. Significant variations in catechin, myricetin, quercetin, and epigallocatechin levels were also observed among cultivars. The traditional apple cultivar ‘Mašanka’ showed higher concentrations of quercetin (0.09 ± 0.01 µg/mL), chlorogenic acid (486.58 ± 5.48 µg/mL), catechin (8.76 ± 0.54 µg/mL), epicatechin (20.22 ± 0.20 µg/mL), and phloridzin (13.48 ± 0.19 µg/mL) compared to the other cultivars. In contrast, conventional cultivars showed higher concentrations of myricetin and procyanidin B1. Moreover, the content of TA, sucrose, and glucose decreased, whereas pH, fructose, TSS (except for ‘Fuji’ and ‘Granny Smith’) increased. The TFC decreased in traditional apple cultivars, while it increased in conventional cultivars; however, the TFC in conventional cultivars remained lower than in traditional ones. Overall, these findings demonstrate that the cold storage of apples significantly affects juice composition and highlight the advantages of traditional apple cultivars for producing juices with enhanced phenolic content and antioxidant activity. Full article

Leaves of Actinidia chinensis Planch. var. deliciosa (A.Chev.) A.Chev. (A. deliciosa) represent agro-industrial byproducts with potential for valorization. The present study evaluated the metabolomics profiling, cytotoxicity, genotoxicity, and antigenotoxicity of the methanolic extract of A. deliciosa leaves. The metabolomics profiling was determined using an untargeted metabolomic approach employing UPLC-HRMS. Cytotoxicity, genotoxicity, and antigenotoxicity were assessed in Chinese hamster ovary K1 (CHO-K1) cells using the in vitro cytokinesis-block micronucleus (CBMN) assay. The metabolic profile of A. deliciosa leaf extracts revealed the presence of three major classes of secondary/specialized metabolites: proanthocyanidins, flavonols, and triterpenoid saponins. Medium-polar metabolites were monomeric fla-van-3-ols, such as (+)-catechin and (−)-epicatechin, oligomeric procyanidins and prodelphinidins, and flavonols. Certain glycosylated flavonols and their derivatives, such as myricetin, quercetin, and kaempferol. Low-polarity metabolites were characterized by low-polarity triterpenoids such as maslinic, corosolic, oleanolic, and ursolic acids. At concentrations of 37.5, 75, and 150 µg/mL, the extract did not significantly increase micronuclei frequency compared to untreated control cells, indicating an absence of genotoxic potential. Moreover, co-treatment of CHO-K1 cells with the extract and mitomycin C (MMC) at 0.025 µg/mL resulted in a significant reduction in micronuclei formation induced by MMC at concentrations of 75 and 150 µg/mL, suggesting antigenotoxic activity likely associated with the phytochemical constituents presented in the extract. Full article

Methotrexate (MTX) is widely used for its chemotherapeutic and immunosuppressive properties, but is limited by oxidative stress-mediated hepatotoxicity. Nanoantioxidant delivery systems can enhance the stability, solubility, and in vivo efficacy of natural antioxidants. This study investigated the hepatoprotective effects of myricetin (MYR), a flavonoid with potent antioxidant activity, and its liposomal nanoantioxidant formulation (MYR-loaded liposomal nanoparticles, MYR-LNPs) against MTX-induced liver injury in male albino Sprague Dawley rats. Sixty rats were randomly allocated to six groups: control, MTX, MYR, MYR-LNPs, and combinations of MTX with MYR-LNPs. MYR-LNPs were successfully formulated and physicochemically characterized, exhibiting a mean particle size of 95.6 nm, a zeta potential of −32 mV, and a narrow polydispersity index, collectively confirming their colloidal stability and suitability for hepatic delivery. MTX markedly disrupted liver function, increasing serum AST, ALT, ALP, and bilirubin and decreasing total protein, albumin, and globulin, whereas co-treatment with MYR-LNPs substantially restored these parameters and outperformed free MYR. MTX-induced oxidative stress, reflected by depleted hepatic GSH and antioxidant enzymes (GPx, SOD, CAT, GST), elevated reactive oxygen species (ROS), malondialdehyde (MDA), and protein carbonyls and downregulated NRF2/HO-1, was significantly counteracted by MYR-LNPs. In addition, MYR-LNPs mitigated MTX-evoked inflammation and nitrosative stress by reducing NF-κB, TNF-α, IL-1β, nitric oxide, and iNOS expression. They corrected apoptotic imbalance by lowering Bax and caspase 3 while increasing Bcl-2. Histopathological and ultrastructural assessments confirmed that MYR-LNPs preserved hepatic architecture and mitochondrial integrity. These findings indicate that MYR-loaded liposomal nanoantioxidants provide superior protection against MTX-induced hepatotoxicity by modulating oxidative stress, inflammation, and apoptosis, supporting their potential as an advanced nanodrug delivery strategy for antioxidant therapy. Full article

Heat stress severely impairs normal plant growth and yield, which significantly limits the horticultural and productive application of most Rhododendron species. In contrast, Rhododendron hainanense exhibits considerable heat tolerance due to its unique growing environment; however, the molecular mechanisms underlying its response to heat stress remain poorly understood. In this study, R. hainanense plants were subjected to heat stress treatment. Combined transcriptomic and metabolomic analyses identified 5454 differentially expressed genes and 152 differential metabolites. The results demonstrated that heat stress significantly induced the accumulation of flavonoids in R. hainanense. Notably, derivatives of myricetin, quercetin, and kaempferol were abundantly accumulated, suggesting their potential role in aiding plant defense against heat stress. The significant up-regulation of specific Rh4CL and RhFLS genes under high-temperature stress, coupled with the substantial accumulation of their flavonoid products (myricetin, quercetin, and kaempferol), indicates a potential role for these metabolites in the thermotolerance of Rhododendron hainanense. These findings provide novel insights into the heat stress response and flavonoid biosynthesis regulation in R. hainanense, highlighting the critical role of flavonoids in plant adaptation to heat stress. This study offers valuable references for the genetic improvement of Rhododendron cultivars with high stress resistance. Full article

Background/Objectives: Osteosarcoma treatment options remain limited due to tumor metastasis and the toxicity of conventional chemotherapy, warranting new therapeutic strategies. A well-founded strategy is the use of flavonoids, a class of phytochemicals possessing pharmaceutical properties that contribute to anticancer effects, including antioxidant and anti-inflammatory properties. This study aimed to evaluate the anticancer potential of flavonoids in osteosarcoma and investigate their interaction with doxorubicin. Methods: In this study, five flavonoids were screened for cytotoxicity and selectivity across four osteosarcoma cell lines and healthy fibroblasts (MRC-5). The interaction between myricetin and doxorubicin was assessed using a fixed-ratio combination approach. Cell migration and invasion were evaluated using cell exclusion/wound healing and 2D co-culture assays. EMT-related gene expressions were assessed by RT-qPCR. Antitumor activity was evaluated in vivo using a chick chorioallantoic membrane (CAM) xenograft model. Results: Myricetin emerged as the most selective compound, exhibiting cytotoxicity against osteosarcoma cells while sparing MRC-5 fibroblasts. Notably, myricetin synergized with doxorubicin (ratio 69:1), enhancing its cytotoxicity and significantly reducing osteosarcoma cell migration in vitro. Myricetin downregulated SNAI1 and MMP9, suggesting modulation of epithelial–mesenchymal transition (EMT)-related pathways. Complementarily, in the CAM xenograft model, myricetin reduced xenograft tumor size, confirming its anticancer activity in vivo. Conclusions: Collectively, these findings emphasize the anticancer potential of myricetin in osteosarcoma through inhibition of the SNAI1/MMP-9 signaling axis. Full article

This study investigated the ethanolic leaf extract of Brazilian pepper tree (Schinus terebinthifolius Raddi) for its metabolite composition and effects on growth performance and intestinal immune gene expression in Nile tilapia (Oreochromis niloticus). Ultra-performance liquid chromatography-electrospray ionization-mass spectrometry (UPLC-ESI-MS/MS) in positive and negative modes revealed a diverse profile of 33 peaks in each polarity, identifying key compounds such as phenolic acids (e.g., gallic acid and ferulic acid), flavonoids (e.g., myricetin-O-glucoside and quercetin 3-O-glucoside), gallotannins (e.g., glucogallin and pentagalloylglucose), and triterpenoids (e.g., masticadienoic acid). A 60-day feeding trial with four groups (control and three extract doses; 0.5%; T0.5%, 1%; T1% and 2%; T2%) demonstrated dose-dependent enhancements in growth metrics, where final body weight increased by up to 106.9 ± 3.6 g, weight gain% by 197.3 ± 3.5%, and the growth rate got more than doubled in T2% (2.4 ± 0.1), alongside improved feed conversion ratio (1.24 ± 0.01) at 30 days and condition factor (stabilized at 2.1 ± 0.0) at 60 days post-feeding. Viscero- and gastro-somatic indices declined insignificantly in most feed groups, indicating improved muscle growth. Biphasic patterns were observed in intestinal gene expression as follows: over 60 days, the IL-1β gene upregulated at low doses but returned to normal at high doses. The IL-10 gene upregulated progressively, promoting an anti-inflammatory balance. In fish fed medium and high doses (T1% and T2%), the IgM gene is upregulated, supporting humoral immunity. These outcomes, linked to the extract’s previously described antioxidants, anti-inflammatory, and antimicrobial bioactive compounds, suggest that S. terebinthifolius is a promising natural feed additive for sustainable tilapia aquaculture and warrants further validation for commercial application. Full article

Background: Myricetin (MYR) is a natural flavonol with antioxidant, neuroprotective, anti-inflammatory, antidiabetic, and cardioprotective activities. Still, its pharmaceutical use is limited by very low aqueous solubility (~16.6 µg/mL) and poor oral bioavailability (<10%). This study aimed to enhance the solubility and potentially improve the bioavailability of MYR by developing an amorphous nanofibrous delivery system. Methods: Electrospinning was applied to fabricate MYR-loaded nanofibers using polyvinylpyrrolidone K30 (PVP30), and the influence of key processing parameters on MYR solubility was evaluated. Nanofibers produced under selected electrospinning conditions were characterized in terms of morphology, encapsulation efficiency, and physicochemical properties. Results: X-ray powder diffraction confirmed complete amorphization of MYR within the BB5 fiber structure (distance: 12 cm, voltage: 25 kV, flow rate: 1.5 mL/h). FTIR analysis indicated hydrogen-bonding interactions between MYR hydroxyl groups and PVP30 carbonyl groups, contributing to stabilization of the amorphous form. SEM images revealed homogeneous, defect-free fibers with diameters below 400 nm, although localized MYR agglomerates were observed. Solubility and release studies demonstrated a characteristic spring-and-parachute effect, enabling rapid MYR release and maintenance of a supersaturated state. Enhanced solubility resulted in significantly improved antioxidant activity in DPPH and CUPRAC assays compared with crystalline MYR. Conclusions: Electrospun PVP30 nanofibers represent a promising platform for improving the solubility, dissolution behavior, and functional activity of poorly soluble bioactive compounds such as myricetin, supporting their potential application in pharmaceutical formulations. Full article

Rapid antigenic drift in the coronavirus spike protein motivates alternative antiviral strategies. We target the conserved nucleocapsid (N) protein—central to RNA binding, genome packaging, and replication—and perform a comparative, cross-species 3D structure-based in silico evaluation. A library of 494 compounds (natural, phytochemical, synthetic) was docked with AutoDock Vina against the MERS-CoV N–terminal RNA–binding domain (NTD; PDB 7DYD) and the C–terminal dimerization domains (CTD) of SARS-CoV (2CJR) and SARS-CoV-2 (8R6E), reflecting the availability of high-resolution, functionally relevant domain structures for each virus. Top-ranked poses underwent ADME profiling and 100 ns GROMACS molecular-dynamics (MD) simulations. Myricetin 3-O-β-D-Galactopyranoside (myricetin) showed the most favorable predicted docking scores across targets (−8.9 kcal/mol, MERS–NTD; −10.1, SARS–CTD; −9.8, SARS-CoV-2 CTD). Curcumin showed moderate predicted affinity (−7.1 to −8.1), while MCC950 achieved consistently favorable docking score (−7.9 to −9.0). ADME results highlighted a trade-off: glycosylated flavonoids offered rich interaction networks but violated oral drug-likeness criteria (e.g., high TPSA), whereas MCC950 met Lipinski/Veber guidelines, supporting translational potential. MD analyses revealed ligand- and target-specific stability: myricetin maintained persistent binding over 100 ns in the SARS-CoV-2 CTD with lower RMSD than comparators; curcumin exhibited transient stability (~30 ns) in MERS- and SARS-bound complexes; MCC950 showed intermittent interactions. Collectively, these findings suggest that the conserved N protein RNA-binding groove represents a resistance-resilient target for broad-spectrum antiviral discovery. Natural flavonoids provide promising scaffolds for optimization, and MCC950 warrants further exploration given its drug-like profile. As this study is purely computational, the results are hypothesis-generating and should be validated via RNA-binding disruption assays, antiviral cell studies, and in vivo models. Full article

Cherry laurel is becoming increasingly popular due to its unique flavor, attractive appearance, and nutritional benefits. However, the morphological, pomological, and biochemical characteristics of the existing population in the Kaynaşlı district of Düzce, Türkiye, remain unclear. To address this, 33 genotypes in this area were systematically characterized in terms of pomological and biochemical traits and their interrelationships. The results revealed a wide variation in fruit and bunch characteristics, including fruit weight (ranging from 2.34 to 7.39 g), the number of fruits per bunch (ranging from 3 to 18), and total soluble solids content (from 10.00% to 22.40%). Notably, the G3 exhibited a superior fruit weight of 7.39 g, surpassing that of currently registered varieties. The study found that phenolic compounds, particularly catechin, were dominant across the individuals, along with significant levels of myricetin, rutin, gallic acid, and syringic acid. Multivariate analyses, including principal component analysis and hierarchical clustering, confirmed a high level of diversity and identified eight individuals with superior traits related to fruit size, phenolic content, color, and astringency. These findings highlight the rich diversity in cherry laurel populations in the region and provide essential breeding material for future studies. Full article

Fermented extracts of Flourensia cernua (F. cernua), enriched with bioactive polyphenols such as caffeic acid, apigenin, myricetin, and quercetin, exhibit strong potential to promote tissue regeneration. However, controlled delivery systems are required to enhance their bioavailability and therapeutic efficacy. In this study, F. cernua extracts (7–21 wt.%) were encapsulated in collagen hydrogels to develop bioactive matrices with sustained release properties. The hydrogel with 14 wt.% enabled sustained extract release from day 5 under physiological conditions and skin-mimicking pH (4.5). Increasing the extract concentration led to enhanced hydration behavior (>1400%) and crosslinking density (>45%), contributing to faster gelation. SEM analysis revealed fibrillar morphologies with amorphous globular domains whose prevalence increased with extract content and conferred improved thermal stability. Mechanical analysis indicated a decrease in matrix stiffness due to repulsive interactions between the extract components and the polymer network. Biodegradation studies showed slow hydrolytic and enzymatic degradation at skin pH in hydrogels containing 7 wt.% extract. All hydrogels demonstrated hemocompatibility, with no erythrocyte lysis. Moreover, hydrogels with 14 wt.% extract significantly enhanced the metabolic activity and proliferation of monocytes and fibroblasts, while 7 wt.% extract reduced TNF-α secretion, indicating anti-inflammatory potential. In vitro wound closure assays revealed 90% contraction within 10 days in fibroblast cultures exposed to 14 wt.% extract-loaded hydrogels. These results support the use of F. cernua-enriched collagen hydrogels as multifunctional scaffolds for wound healing and tissue regeneration. Full article

The blood–brain barrier (BBB) is a structure that regulates the exchange of substances between the peripheral circulation and the central nervous system (CNS), thereby protecting this environment. An increase in BBB permeability may lead to the influx of inflammatory cells, resulting in neuroinflammation and neurodegeneration. The integrity of the BBB is maintained due to the specific properties of brain endothelial cells. Considering the importance of brain endothelial cells in the BBB during inflammatory processes, these cells may be a target for anti-inflammatory agents. Polyphenols are substances exhibiting the ability to decrease inflammation; therefore, in our research, we aimed to examine their effectiveness in a brain endothelial cell culture stimulated with the pro-inflammatory cytokine TNF-α. The tested polyphenols were myricetin, chrysin, resveratrol, and curcumin. ELISA tests revealed that myricetin and chrysin decreased the concentrations of the pro-inflammatory cytokines IL-1ß, IL-6, and IL-8 secreted by brain endothelial cells. The results of flow cytometry indicate that chrysin and resveratrol are the most potent in downregulating the expression of VCAM-1 on the surface of brain endothelial cells. The obtained results confirm the anti-inflammatory potential of polyphenols in brain endothelial cells. The selected polyphenols also contribute to increasing brain endothelial cell viability and act as antioxidants. Full article

Background: Parthenocissus quinquefolia (Virginia creeper), widely distributed and used in Chile, lacks a systematic characterization of its bioactive components. This study synthesizes the evidence on the phytochemical composition and biological activities of P. quinquefolia, with emphasis on metabolites involved in redox regulation and inflammation. Methods: A systematic review was conducted following PRISMA 2020 guidelines. Searches were performed across four electronic databases, including original studies reporting antioxidant and anti-inflammatory effects. Results: Of 665 records identified, 14 studies met the inclusion criteria. Phytochemical analyses revealed phenolic compounds, particularly flavonoids (e.g., catechin, epicatechin, gallocatechin, epigallocatechin, quercetin, rutin, isoquercitrin, myricetin, luteolin, naringin) and stilbenes (e.g., ε-viniferin, miyabenol C). These metabolites exhibit antioxidant activity through ROS scavenging, metal chelation, and Nrf2/ARE activation. Anti-inflammatory effects were attributed to the downregulation of NF-κB, AP-1, and MAPK signaling, inhibition of NLRP3 inflammasome activation, and suppression of COX-2/iNOS expression. Conclusions: P. quinquefolia is a rich source of phenolic metabolites with robust antioxidant and anti-inflammatory mechanisms. The consistency of molecular responses across studies highlights its potential as a promising candidate for phytotherapeutic development targeting oxidative stress and inflammatory pathways. Full article

Hair loss is a prevalent condition with various causes, and effective treatments are in high demand. Cacumen Platycladi (Platycladus orientalis leaves), a traditional Chinese medicine, has been historically used to prevent hair loss. This study aimed to evaluate the efficacy and mechanisms of Cacumen Platycladi extract (CPE) in preventing hair loss. Using a gradient extraction method with 1,3-butanediol, ethanol, and water, bioactive compounds like quercitrin, myricetin, and myricitrin were enriched and identified via Liquid Chromatography–Mass Spectrometry (LC-MS). The results showed that CPE inhibited 5α-reductase activity, enhanced the antioxidant capacity of human dermal papilla cells (HDPCs), and upregulated the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway to promote vascular endothelial growth factor (VEGF) and collagen type XVII (COL17) expression. A 12-week clinical trial demonstrated that CPE significantly reduced hair loss and increased local hair density compared to placebo, with no adverse effects. These findings support the potential of CPE as a safe and effective natural alternative for hair loss prevention. Full article

Plant-based extracts are rich sources of phenolic compounds, which may act as skin antiaging mediators. Herein, Cistus albidus L. (Ca), Cistus ladanifer L. subsp. ladanifer (Cl) and Cistus salviifolius L. (Cs) were selected to test whether their phytochemical profile and bioactive potential align to target human skin aging. Hydroethanolic extracts (HEs) were prepared and characterized using infrared vibrational spectroscopy (FTIR-ATR) and liquid chromatography–mass spectrometry (LC-MS). Non-toxic concentrations were screened, and cytoprotective and antioxidant effects were studied in tert-butyl hydroperoxide-stimulated normal human dermal fibroblasts (NHDFs). Lipopolysaccharide-stimulated RAW 264.7 macrophages were used to assess anti-inflammatory activity, the Organization for Economic Co-operation and Development (OECD) Test Guideline No. 439 was used to assess irritant effects, and the anti-senescence potential was assessed in etoposide-stimulated NHDFs. A series of enzymatic inhibition assays was performed. All extracts comprised ellagic acid derivatives, as well as myricetin and quercetin derivatives in Cs and Ca. The HE of Cs was also markedly composed of ligstroside. At non-toxic concentrations, cytoprotective effects were observed in NHDFs. However, only Cs and Cl exhibited significant antioxidant activity in these cells (p < 0.001 and p < 0.0001, respectively). In addition to that, Cl demonstrated highly significant anti-inflammatory (p < 0.0001) and anti-senescence (p < 0.0001) effects. Cs and Cl showed a remarkable potential to inhibit elastase; in addition, Cs also showed anti-hyaluronidase and anti-tyrosinase activities. Meaningfully, Cs and Cl extracts did not exhibit skin irritant effects. The unveiled potential of Cl in skin aging offset highlights the need to elucidate the detailed mechanisms of action, paving the way for the development of skin anti-aging formulations. Full article