Search Results (1,048)

The coexistence of emulsified oil, dissolved organics, and heavy metal ions in industrial oily wastewater makes one-step treatment highly challenging. Herein, an organic-inorganic co-modified PVDF composite membrane (MTSP) was fabricated via nonsolvent-induced phase separation, with tea polyphenols, SiO₂, and fibrous MXene synergistically incorporated. The resulting membrane exhibited a superhydrophilic/underwater oleophobic surface, with a water contact angle of 1° and an underwater oil contact angle of ~136°, owing to the optimized surface chemistry and hierarchical pore structure. As a result, the MTSP membrane effectively suppressed oil fouling while enabling rapid water transport. At 0.1 bar, the optimized membrane delivered an oil/water separation efficiency of ~99.5% and a high flux of 2420–2670 L·m⁻²·h⁻¹, while maintaining >99% separation efficiency for various emulsified oils, including kerosene, edible oil, n-hexane, and 1,2-dichloroethane. It also showed excellent recyclability and chemical stability, retaining >98–99% efficiency after five cycles and after 24 h exposure to pH 1 and pH 12 conditions. Notably, for complex simulated wastewater containing emulsified kerosene, phenol, and Fe³⁺, Cu²⁺, Zn²⁺, and Cd²⁺, the membrane maintained ~99% oil/water separation efficiency and simultaneously removed ~79% of phenol and 70–86% of heavy metal ions in a single filtration process. The superior performance is attributed to the synergistic effects of the superhydrophilic/underwater-oleophobic membrane surface, hierarchical transport channels enabling rapid water permeation, and multifunctional sites that adsorb/coordinate dissolved pollutants. This work provides a simple, scalable design strategy for PVDF-based membranes that integrate high-flux separation, antifouling performance, and multi-pollutant remediation for the treatment of complex oily wastewater. Full article

Candida albicans (C. albicans) is an opportunistic fungal pathogen capable of causing a wide range of infections, including mucosal and systemic candidiasis. In the oral cavity, fungi represent a minor component of the microbiome but can significantly contribute to morbidity, particularly under conditions of dysbiosis or immunosuppression. Treatment remains challenging due to increasing multidrug resistance. This study investigates the in vitro antifungal potential of Viroelixir, a standardized polyphenol blend derived from green tea and pomegranate and enriched in catechins (including epigallocatechin gallate, EGCG), ellagitannins (notably punicalagin), ellagic acid, and flavonoids, with particular focus on its potential anti-virulence mechanisms. Methods: The effect of Viroelixir on C. albicans growth was assessed using MTT assay, optical density measurements, colony formation, carbohydrate quantification, and pH variation analysis. Biofilm formation, morphological transition, ROS production, necrosis, virulence gene expression, adhesion, and host immune responses were also evaluated. Results: Viroelixir significantly inhibited C. albicans growth and reduced colony formation compared with untreated controls. The formulation also inhibited biofilm formation and markedly reduced pseudohyphal development, reaching up to 94% reduction under specific treatment conditions. Flow cytometry analysis showed an increase in dead fungal cells, reaching approximately 88% following exposure to Viroelixir at the highest tested concentration. In addition, Viroelixir reduced the transcript levels of several virulence-associated genes, including SAP1–SAP9 and EAP1. In epithelial cell co-culture models, pre-treatment of C. albicans with Viroelixir reduced fungal adhesion and attenuated epithelial inflammatory responses, including IL-6, IL-8, and hBD-2 production, and was associated with reduced activation of the TLR4-NF-κB signaling pathway. Conclusions: These findings suggest that the antifungal and anti-virulence effects observed may be associated with the polyphenolic compounds present in the Viroelixir formulation, highlighting its potential as a promising in vitro antifungal candidate against C. albicans. Full article

To reveal how the characteristic flavor of jasmine tea is generated, this study analyzed the coordinated changes in sensory properties, chemical components, and aroma migration behavior during scenting. Sensory evaluation, biochemical assays, and headspace solid-phase microextraction–gas chromatography–mass spectrometry (HS-SPME-GC-MS) integrated with orthogonal partial least squares discriminant analysis (OPLS-DA) and relative odor activity value (rOAV) filtering were applied to tea samples before and after scenting. After scenting, aroma and taste scores increased significantly, and liquor color shifted from tender green to pale yellow. Amino acids and soluble sugars increased, while astringent substances such as tea polyphenols and catechins decreased. Key floral compounds, including cis-3-hexenyl benzoate and methyl anthranilate, were transferred from jasmine flowers to the tea base and enriched, likely contributing to the typical aroma profile. The retention rate of aroma in spent flowers was positively correlated with hydrophobicity (logP, r > 0.46, p < 0.01) and negatively with polarity (TPSA, r > −0.42, p < 0.05), suggesting regulation by hydrophobic partitioning. In contrast, aroma transfer to the tea base showed no simple correlation with any single physicochemical parameter, suggesting multi-factor regulation. This study provides insights into the scenting process and offers a theoretical reference for quality control in jasmine tea production. Full article

This study optimized stabilizer type and concentration, and screened natural antioxidant combinations to enhance the stability of a protein beverage fortified with vitamins A, D₂, and D₃. Three stabilizers—carrageenan, sodium carboxymethyl cellulose (Na-CMC), and microcrystalline cellulose (MCC)—were evaluated at 0.15–0.45% (w/v) during accelerated storage at 45 °C for 21 days. Stability was assessed using Turbiscan analysis, pH, particle size, Zeta potential, and color. MCC at 0.35% demonstrated the best stabilization, with minimal changes in Turbiscan Stability Index, particle size, and Zeta potential. Five natural antioxidants—dl-α-tocopherol, vitamin C, epigallocatechin gallate (EGCG), tea polyphenols (TP), and pyrroloquinoline quinone (PQQ)—were screened for vitamin protection using HPLC. Although vitamin C exhibited the highest in vitro DPPH radical scavenging activity (IC₅₀ = 3.44 μg/mL), TP and EGCG provided superior protection of vitamins in the emulsion system. A synergistic antioxidant blend of EGCG, TP, and dl-α-tocopherol in a 4:4:2 mass ratio was identified as optimal, significantly prolonging vitamin retention over 21 days and yielding the longest predicted shelf-life (>84 days at 25 °C). These findings provide a practical formulation strategy for enhancing the physical and nutritional stability of functional protein beverages. Full article

Heat stress is a major environmental stressor in poultry production that reduces growth performance and induces oxidative stress, inflammatory responses, and lung tissue injury. This study investigated the protective effects of dietary supplementation with Ginkgo biloba extract and tea polyphenols against heat stress-induced lung injury in broilers. A total of 320 one-day-old broilers were reared under standard management conditions until 21 days of age. Subsequently, 300 birds with similar body weight were selected and randomly allocated into six groups: a thermoneutral control group, a heat stress group, a heat stress group supplemented with 300 mg/kg tea polyphenols, and three heat stress groups receiving 300 mg/kg tea polyphenols combined with 100, 300, or 600 mg/kg Ginkgo biloba extract. The analysis of the results showed that heat stress significantly reduced the average daily gain and feed intake while increasing the feed conversion ratio. It also markedly increased serum lactate dehydrogenase activity and malondialdehyde levels, while decreasing antioxidant-related indicators, indicating the occurrence of oxidative stress and inflammatory responses. Histological examination revealed lung injury characterized by alveolar wall thickening, epithelial cell shedding, and disruption of the endothelial barrier, accompanied by upregulated expression of heat shock proteins and inflammation-related signaling genes. Supplementation with tea polyphenols alone partially alleviated these changes. Notably, the combined supplementation of Ginkgo biloba extract and tea polyphenols exerted more pronounced protective effects, significantly enhancing antioxidant capacity, attenuating inflammatory responses, and maintaining pulmonary barrier integrity. Among the tested levels, the groups receiving 300 mg/kg Ginkgo biloba extract in combination with tea polyphenols showed the most evident improvements. These findings suggest that the combined use of these plant-derived extracts effectively mitigates heat stress-induced lung injury in broilers. Full article

The herbal tea industry has experienced substantial growth, particularly regarding green tea (Camellia sinensis). In the manufacturing of filter tea, fine herbal dust is generated as a residual by-product during grinding and sieving and is typically discarded as waste. This study aims to explore the application of ultrasound-assisted extraction (UAE) for secondary valorisation of green tea herbal dust by investigating the effects of various parameters on extraction efficiency. Antiradical activity of UAE extracts was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, and the total phenolic content (TPC) was measured using Folin–Ciocalteu’s assay. Furthermore, selected phenolics were quantified by HPLC and qualitatively characterised by liquid chromatography coupled with electrospray ionisation and quadrupole time-of-flight tandem mass spectrometry (LC-ESI-QToF-MS/MS). The results demonstrate that UAE parameters have a pronounced influence on the antioxidant activity, TPC, and individual polyphenolic profile of green tea herbal dust extracts. Ethanol–water mixtures at a ratio of around 40–60%, as well as moderate impulse regimes (around 60%) and extraction times (around 10 min), were the most suitable for extracting green tea polyphenols. Epigallocatechin gallate was the predominant phenolic component in most extracts, alongside epicatechin, epigallocatechin, catechin, and gallic acid. The findings highlight the UAE technique as a robust, green, and scalable method for valorising green tea by-products, thereby facilitating the development of high-value natural extracts for applications in the food, pharmaceutical, and cosmetic industries. Full article

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has driven the global COVID-19 pandemic, imposing a tremendous burden on public health. As the virus continually evolves through rapid mutations, the pandemic has transitioned into a prolonged endemic phase. Despite the development of novel drugs and vaccines, clinical outcomes remain suboptimal for vulnerable populations, including the elderly and those with comorbidities or compromised immunity. Tea polyphenols, a class of structurally diverse and bioactive nutraceuticals, may modulate viral entry, replication, and host inflammatory pathways implicated in disease progression through pleiotropic effects on viral attachment, membrane fusion, intracellular replication, and proteolytic processing. Here, we provide an updated chemo-biological perspective on the antiviral and immunomodulatory mechanisms of tea polyphenols against SARS-CoV-2. Current evidence highlights their potential to serve as promising candidates for further mechanistic and translational investigation as adjunctive strategies and nutraceuticals for COVID-19 management. Importantly, no large-scale randomized controlled trials have yet demonstrated clinical benefit of tea polyphenols in COVID-19. Full article

Achieving rapid and non-destructive assessment of tea quality is essential for intelligent tea production and quality control. In this study, an integrated hyperspectral and deep learning framework was developed to estimate tea quality constituents across seasons and physical states. Samples included field fresh leaves, dried tea leaves, and tea powder, were collected in spring, summer, and autumn. Tea polyphenols and catechins were predicted using original reflectance, harmonic features, and wavelet features fused into multi-domain indices. Extreme gradient boosting, Gaussian process regression, and convolutional neural networks (CNN) were systematically compared to construct the quality estimation models. The result showed that three-feature indices consistently outperformed two-feature indices, yielding R² from 0.48 to 0.71. CNN achieved the best overall performance among the three modeling approaches, with its optimal accuracy obtained for tea powder samples in autumn, yielding R² values of 0.81 and 0.76 for tea polyphenols and catechins, respectively. This framework provides an accurate, non-destructive tool for tea quality evaluation and traceability, offering technical support for intelligent agriculture and quality control across the tea industry chain. Full article

Tea (Camellia sinensis L.) infusion is the second most commonly consumed drink in the world after water, valued for its sensory qualities and health-promoting properties. Tea contains a range of chemical compounds that give it specific nutritional and refreshing properties. These include alkaloids, polyphenolic compounds, carbohydrates, amino acids, enzymes, and aromatic compounds. The content of individual compounds in tea leaves is impacted by factors such as the variety, region, and cultivation method, as well as specific processing operations. The aim of the present study was to investigate the content of bioactive compounds in a selection of organic and conventional tea infusions characterized by different degrees of leaf fragmentation. The analysis of selected phenolic acids, catechins, quercetin, and caffeine in black tea and black Earl Grey tea infusions was conducted using high-performance liquid chromatography (HPLC). The study confirmed that the chemical composition of tea infusions is significantly impacted by the type of tea, cultivation practices, and form of the leaves, and revealed some previously underexplored interactions between the leaf fragmentation and cultivation system effects. From a consumer or product design perspective, organic loose-leaf Earl Grey teas appear to offer the most favourable balance of catechins, and flavonoids whereas conventional bagged black teas provide higher phenolic acid content. Full article

The α-glucosidase inhibitory activity of Keemun black tea arises from complex interactions among its major polyphenols, which cannot be reliably predicted from the activities of isolated compounds. In this study, eight dominant polyphenols were investigated using a quantitative reconstruction–omission framework designed to reflect typical household tea brewing. The fully reconstructed system recovered approximately 72% of the inhibitory activity of the diluted native infusion, supporting the functional representativeness of the selected compounds. Systematic omission experiments revealed that antagonistic interactions, particularly among theaflavins, dominated the net inhibitory outcome, with removal of the most potent inhibitor, theaflavin-3,3′-digallate (TFDG), paradoxically increasing overall activity. Pairwise Combination Index analysis further demonstrated concentration-dependent biphasic interactions, exemplified by the epigallocatechin-3-gallate (EGCG)–TFDG pair, while molecular docking suggested overlapping binding sites as a potential structural basis for competitive inhibition. Collectively, this work provides a system-level dissection of α-glucosidase inhibition in black tea. Although the reconstructed system does not fully capture all contributions, the proposed framework offers a generalizable strategy for investigating interaction-driven bioactivity in complex dietary matrices and for further mechanistic studies. Full article

Polygonatum cyrtonema Hua (PCH) is traditionally recognized as both an edible and medicinal food source. Its rhizomes contain numerous bioactive compounds, notably polysaccharides and flavonoids, which serve as key constituents in functional food development. However, the cultivation of PCH is often hindered by allelopathic effects, which diminish its quality and restrict its industrial application. To mitigate these allelopathic influences, three types of biochars derived from maize straw (MB), rice husk (RB), and tea stem (TB) were applied at concentrations of 0%, 2%, and 4%. Initially, the physicochemical properties of these biochars were characterized, followed by an evaluation of their impact on (1) the synthesis of quality-related components, secondary metabolites, and allelochemicals within PCH rhizomes and (2) the fundamental physicochemical properties and bacterial community structure of the PCH rhizosphere soil. The findings indicated that the application of 4% RB significantly enhanced the content of total polysaccharides by 48.5%, total flavonoids by 30.2%, total saponins by 28.6%, and total polyphenols by 18.3%, while concurrently reducing protein (PRO) and free amino acid (FAA) concentrations in the rhizomes. Non-targeted metabolomic analyses revealed that biochar amendments (1) upregulated metabolites involved in the citrate cycle and galactose metabolism pathways, thereby facilitating energy supply and precursors for polysaccharide biosynthesis; (2) downregulated metabolites involved in the arginine biosynthesis pathway, which is unfavorable for protein and amino acid synthesis; (3) decreased the abundance of six identified allelochemicals, including 5-hydroxy-L-tryptophan and andrographolide, with the most pronounced effect observed in the 4% TB treatment (T2); (4) improved soil physicochemical parameters such as pH, soil organic matter (SOM), total nitrogen (TN), and available potassium (AK); and (5) altered the rhizosphere bacterial community by enriching beneficial phyla, notably Myxococcota and Gemmatimonadota. These modifications in soil properties and bacterial community composition were closely associated with enhanced rhizome quality and a reduction in allelochemical accumulation. Collectively, the results of this study elucidate the potential mechanisms linking biochar application to allelopathy mitigation, optimization of soil microbial communities, and improvement of PCH rhizome quality. This research provides a theoretical basis for the production of high-quality PCH while concurrently minimizing allelochemical accumulation in its rhizomes. Full article

Background/Objectives: Precocious puberty in girls currently appears to be one of the main problems in pediatric endocrine gynecology. Early onset of menstruation (EOM) means that the age at which the first menstruation occurs is lower than the average/median for the population, which ranges from 12 to 13 years and depends primarily on ethnic origin. Depending on age and severity of symptoms, these disorders negatively affect girls’ quality of life in many areas, including school life, family relationships, and everyday life. Methods: This article provides a scoping review summarizing scientific evidence from human studies on the association between substances derived from green tea (flavanols) and soy (isoflavones) and precocious puberty in girls. Results: Despite the relatively small number of girls enrolled in the studies, available scientific evidence from randomized controlled trials (RCTs) suggests that polyphenols from decaffeinated green tea (DGTP) may contribute to lowering the age of first menstruation in girls living with obesity. The effect of soy isoflavones or soy in the context of premature menstruation in girls is unclear. Most studies report that it may have no effect on the age of first menstruation, while individual studies suggest that very early exposure to soy (< 4 months of age) may result in earlier puberty, and others suggest that higher consumption of soy isoflavones delays this process. Conclusions: Further well-designed intervention studies in humans are needed to better understand the endocrine and metabolic relationships regarding the role and importance of specific polyphenols in the pathogenic mechanisms of the development and treatment of precocious puberty in girls. Full article

Quantum dots (QDs) have drawn a lot of attention as photocatalytic materials due to the growing need for environmentally friendly wastewater treatment technologies. Among these, carbon-based QDs, including graphene oxide quantum dots (GOQDs), graphitic carbon nitride (g-C₃N₄), and carbon quantum dots (CQDs), have exceptional optical, electronic, and surface characteristics that increase their suitability for degrading pollutants when exposed to sunlight or visible light. These composites are better at transferring charges, staying stable in light, and breaking down pollutants. Metal-based QDs like ZnO and CdS also have strong photocatalytic activity, but their sustainability remains a concern due to the potential release of toxic ions when they corrode in light. The green synthesis approach addresses these challenges. Using natural extracts, like polyphenols from tea leaves, to biofunctionalize surfaces has been shown to reduce toxicity and improve photocatalytic performance. Green synthesis using renewable precursors solves problems with toxicity, resource depletion, and environmental pollution, which supports a low-impact and circular technological approach. This study examines recent developments in the making, modifying, and use of QD-based photocatalysts in the environment, with a focus on CQD/g-C₃N₄ hybrid systems. Future research should focus on making green, non-toxic, regenerable, and highly active carbon-based QDs for safe large-scale water treatment. Full article

Most polyphenols (and tannins in their composition), secondary plant metabolites with positive effects on the human body, are soluble in water, which makes them environmentally friendly and the most accessible solvent in everyday life. The aim of this study was to examine the effects of water extraction methods, hot water extraction and maceration, on the amounts of these compounds isolated from plants, compared with ultrasonic extraction, which is not readily available. Seven Ericaceae and four Rosaceae species were selected for study, whose leaves are used in folk and/or official medicine to make herbal teas. Total polyphenolics were determined by the Folin–Ciocalteu method spectrophotometrically and total tannins by calculating the difference between the total and remaining polyphenolic content after tannin precipitation. The results demonstrated that ultrasound was not the most effective method for extracting polyphenols: it yielded the highest polyphenol amounts only from two Rosaceae species, Potentilla anserina and Alchemilla vulgaris. The hot water extraction of polyphenols was more effective than maceration. Hot water was more effective in extracting polyphenols from evergreen plants. Regardless of the extraction method, most of the polyphenols were extracted with water from Arctostaphylos uva-ursi and tannins from Rhododendron tomentosum leaves. The studied Ericaceae species accumulate higher-polarity tannins than the studied Rosaceae representatives. Full article

Rosehip-based products are rich in polyphenols with recognized health benefits, making accurate characterization essential for quality control and functional evaluation. Conventional analytical approaches for polyphenol determination are often time-consuming, costly, and environmentally demanding. In this study, a sustainable analytical method based on capillary zone electrophoresis coupled with diode array detection (CE–DAD) was developed as a green and accessible screening method for polyphenol analysis in rosehip-based products. Twelve polyphenolic compounds belonging to different classes (stilbenes, flavonols, flavanols, flavanones, and flavones) were used to optimize the electrophoretic conditions, including the buffer pH, voltage, and electrolyte concentration. Herbal tea and supplement samples were analyzed before and after a simple cartridge-based clean-up step to reduce matrix interferences. The method enabled simultaneous profiling of multiple polyphenol classes in a single CE–DAD run, showing excellent linearity (R² > 0.99), run to run reproducibility (RSD 0.8–1.6%), and sensitivity (LOD 0.4–1.4 μg/mL; LOQ 0.9–4.7 μg/mL). Eight target polyphenols were identified and quantified in real samples. Polyphenol profiling was complemented by DPPH and ABTS antioxidant assays, allowing a functional interpretation of compositional data and a case-based comparison between different product formulations. Specifically, the herbal tea showed the values of a 13.8 mg Trolox/g sample (80.5% DPPH inhibition) and 15.3 mg Trolox/g sample (98.5% ABTS inhibition), whereas the food supplement presented a 7.4 mg Trolox/g sample (34.2% DPPH inhibition) and 7.4 mg Trolox/g sample (54.1% ABTS inhibition). Method sustainability and applicability were also evaluated using the Blue Applicability Grade Index (BAGI), confirming a low environmental footprint. Full article