The ability of flowers to sustain fragrance release during the scenting process dominates the aroma quality of scented tea, rather than the capacity of tea dhool to passively adsorb volatiles. Plucked flowers remain metabolically active, whose physiological status governs the persistence and intensity of fragrance emission. Traditional practice has focused on maximizing aroma uptake by a low‑moisture tea dhool, inadvertently accelerating floral dehydration and metabolic collapse, thereby prematurely terminating peak fragrance release. This study introduces a novel "tea nurturing flowers" perspective, investigating how tea dhool moisture content modulates Osmanthus physiology and shapes the aroma quality of Osmanthus black tea (OBT). An optimized moisture level (25%) preserved cellular integrity, delayed water loss, and maintained stomatal opening, collectively sustaining floral volatile emission. By contrast, insufficient moisture (5-10%) caused plasmolysis and stomatal closure, while over‑hydration (45%) induced cell rupture and blockage of the porous tea dhool, impairing volatile transfer. Consequently, OBT produced at 25% moisture exhibited a more intense and persistent floral aroma, with elevated levels of key volatiles such as β‑ionone. Overall, this study repositions tea dhool from a merely passive adsorbent to a moisture‑mediated regulator of flower vitality, providing a mechanistic foundation and practical guidelines for improving scented tea quality.

ABSTRACT Ingested nanoplastics (NPs) readily translocate across the intestinal barrier due to their small size, posing a pervasive threat to human health. Current mitigation approaches, constrained to environmental water purification or postexposure injury alleviation, entail unavoidable NPs ingestion or organism damage. Effective strategies to impede NPs internalization at the lumen stage and promote safe elimination remain limited. Here, an edible biohybrid platform, composed of a natural polyphenol reductant, redox‐active ferric ions, and H 2 O 2 ‐generating Enterococcus faecalis , is developed to trap NPs within the intestine. The platform enables persistent in situ generation of hydroxyl radicals in the intestine through Fenton reactions, accelerating the oxidative aging and subsequent NP agglomeration into micrometer‐scale clusters that exceed the physiological pore‐size limit of intestinal barrier. In an in vitro intestinal barrier model, the platform achieved a 96.02% NPs clearance efficiency within 24 h. Daily oral co‑administration effectively blocked NP penetration into lamina propria, alleviated intestinal inflammation, tight‑junction disruption, and mucosal damage in mice, as well as a protective effect further corroborated by the diminished NP fluorescence in C. elegans . Validated with both polystyrene and polypropylene NPs, this strategy of directed regulation of intestinal NP behaviors offers a green and generalizable approach to combat the NP exposure hazards.

The temperature parameter of scenting process, which governs the vitality of fresh flowers and the release of floral volatiles, is still empirically determined. Here, we investigate how environmental temperature regulates osmanthus vitality and enzymatic activity to shape the aroma quality of osmanthus black tea (OBT). Results showed that the moderate-temperature (25 °C and 30 °C) exhibited superior sensory quality, accompanied by slower water loss and delayed wilting of osmanthus, which favored aroma retention during scenting. Carotenoid cleavage dioxygenase (CCD) content peaked (1268 U/g), associating with the accumulation of β-ionone (a typical floral aroma), while β-glucosidase (β-GC) activity gradually increased with rising temperature, contributing to the formation of esters such as γ-decalactone (fruity aroma). Volatile profiling revealed that 30 °C promoted the accumulation of multiple key volatile compounds (linalool, β-ionone, and γ-decalactone), resulting in the highest total volatile content and overall odor activity value (OAV). In contrast, low temperature (20 °C) maintained flower freshness but limited aroma-related enzymatic responses and volatile accumulation. High temperature (35 °C) caused rapid petal dehydration (over 73% water loss within 4 h) and premature withering, inhibiting aroma release and reducing total volatile content. Overall, these findings establish 30 °C as the optimal environmental temperature for scenting OBT and provide a flower-centric, physiologically grounded strategy for temperature control.

Despite the rapid expansion of the pure tea beverage market ($35 billion by 2025), shelf-life sedimentation remains a major challenge as 80% of raw materials fail conventional stabilization techniques (e.g., membrane filtration), attributable to unclear colloidal stability mechanism regarding the tea infusion components and processing-induced evolution. In our work, 17 typical green tea were analyzed to identify protein and polyphenol as the key stability predictors, and a rapid screening method was developed and validated. Characterization revealed that sterilization drives divergent fates, with stable samples reinforcing β-sheet and hydration networks, whereas sediment-prone samples undergo random coil expansion and polyphenol cross-linking. While EGCG accelerates initial sedimentation, EC modulates the final sediment volume in actual tea systems. Moving beyond processing intervention in tea beverages, this work focuses on "colloid-suspension" phase conversion mediated by the tea infusion components, providing a data foundation as well as targeted processing of raw materials for sediment-free tea beverages.

Flavored teas have gained popularity because they combine sensory appeal with potential health benefits. Ganoderma lucidum (GL) is a promising functional beverage ingredient owing to its high medicinal value. However, its strong fungal off-flavor and bland taste limit consumer acceptance. Yellow tea (YT), characterized by a mild-sweet aroma and mellow mouthfeel developed during sealed yellowing, provides a suitable matrix for moderating the sensory defects of GL. This study designed a blend-brewing strategy, optimizing the YT to GL ratio (2:3, w/w) and comparing covered (CB), standard (SB), and open-topped brewing (OB) methods. SB achieved the most balanced sensory profile. In contrast, CB intensified bitterness and astringency, which were associated with higher concentrations of EGCG, gallic acid, and theobromine, whereas OB produced a relatively flat taste because of insufficient extraction. Brewing also reshaped self-assembled nanoparticles, with CB inducing pronounced aggregation and SB yielding a broader size distribution, smoother surfaces, and more balanced colloidal proteins, catechins, and caffeine. Removing nanoparticles substantially decreased infusion mellowness, supporting a contribution of the NP-enriched fraction to mouthfeel. These findings demonstrate that Ganoderma lucidum yellow tea (GY) blending and brewing method modulate sensory quality through chemical extraction and colloidal nanoparticle organization, providing a practical strategy to improve Ganoderma lucidum palatability and develop functional tea beverages.

Colonization of commensal fungi, particularly Malassezia, and immune-cell recruitment, are two essential drivers initiating processes in dermatitis, which necessitates interventions to prevent skin barrier damage and immune hyperactivation. Herein, we construct theabrownin-selenium nanoparticles (TB-Se NPs) as a dual-function antifungal and immunomodulatory platform with pronounced hair-follicle penetration for counteracting Malassezia-induced dermatitis and recurrence. TB-Se NPs are stabilized by conjugated biomacromolecules from tea-derived polymer TB, yielding reduced size and enhanced stability. Mechanistically, covalent O═C─O bonding between TB-Se NPs and cell walls boosts surface adsorption sixfold compared to bare Se NPs. This interaction disrupts fungal envelope integrity and facilitates a "Trojan Horse" effect, promoting the release of selenols via thiol exchange and interfering with sulfur-related metabolism to induce fungal death. In a Malassezia-induced dermatitis model, follicle-targeted TB-Se NPs suppressed dermatitis phenotypes by restraint on fungal overgrowth and prevention of abnormal keratinocyte proliferation. TB-Se NPs also interfered with neutrophil adhesion and migration capacities and local amplification of the inflammatory response. A Long-term firewall against fungi recurrence has been established by TB-Se NPs, which pre-activate CD4+ T cells and memory T cells to strengthen the immune memory response. Collectively, TB-Se NPs represent a dual-function antifungal and immunomodulatory therapeutic strategy for preventing fungal-induced dermatitis and relapse.

Chrysanthemum × morifolium (Ramat) Hemsl. (Hangbaiju), which has been widely consumed as a herbal tea for over 3000 years, is renowned for its biosafety and diverse bioactivities. This study investigates the impact of polyphenol-rich Hangbaiju extracts (HE) on high-fat diet-induced obesity in mice. HE contains phenolic acids and flavonoids with anti-obesity properties, such as apigenin, luteolin-7-glucoside, apigenin-7-O-glucoside, kaempferol 3-(6″-acetylglucoside), etc. To establish the obesity model, mice were randomly assigned into four groups (n = 8 per group) and administered with either HE or water for 42 days under high-fat or low-fat dietary conditions. Administration of low (LH) and high (HH) doses of HE both significantly suppressed body weight growth (by 16.28% and 16.24%, respectively) and adipose tissue enlargement in obese mice. HE significantly improved the serum lipid profiles, mainly manifested as decreased levels of triglycerides (28.19% in LH and 19.59% in HH) and increased levels of high-density lipoprotein cholesterol (44.34% in LH and 54.88% in HH), and further attenuated liver lipid deposition. Furthermore, HE significantly decreased the Firmicutes/Bacteroidetes ratio 0.23-fold (LH) and 0.12-fold (HH), indicating an improvement in the microecological balance of the gut. HE administration also elevated the relative abundance of beneficial bacteria (e.g., Allobaculum, norank_f__Muribaculaceae), while suppressing harmful pathogenic proliferation (e.g., Dubosiella, Romboutsia). In conclusion, HE ameliorates obesity and hyperlipidemia through modulating lipid metabolism and restoring the balance of intestinal microecology, thus being promising for obesity therapy.

Liubao tea, a traditional dark tea, has gained widespread recognition for various health benefits. In this study, the effects of Liubao tea extract (LTE) on obesity-related hyperlipidemia and the potential mechanism involved were explored. Anti-obesity compounds such as tricetin, isovitexin, tiliroside, etc. in LTE were identified. In high-fat diet mouse models, LTE effectively reduced tissues, organs, and body weight growth, and restored abnormal serum lipid levels. LTE could reverse adipocyte enlargement, lipid accumulation, and hepatic microstructure abnormalities. Notably, LTE reshaped gut microbiota by boosting beneficial bacteria (e.g., Bacteroides, Akkermansia, Psychrobacter) and suppressing harmful bacteria (e.g., Dubosiella, Faecalibaculum). Spearman correlation analysis unveiled significant associations between serum lipid levels, weight gain, LTE dosage, and gut microbiota, underlining the modulatory effects of LTE on metabolic disorders via the regulation of intestinal microbiota. Collectively, LTE could serve as a potential therapy for obesity-related hyperlipidemia prevention.

Shaking, essential in oolong tea production, is becoming an innovative method to impart floral fragrance. Research on shaking primarily concentrates on biological underpinnings, including modifications in gene expression and stress-triggered enzymatic catalysis, and consequent physicochemical properties. Water phase and distribution, reshaped by shaking and affected the biological and physicochemical alterations of tea leaves, is always ignored. This work utilized TEM, LF-NMR, UPLC-QqQ-MS, and GC-TOF-MS to explore physicochemical alterations during shaking. Results revealed shaking induced stomatal opening, water migration from stems to leaf veins, and a reduction in free water, transformed into bound water. Mechanical stimulation disrupted cell microstructures, including vacuoles, chloroplasts, and cell walls, releasing precursors and enzyme substrates. Shaking triggered intracellular physicochemical reactions that decreased polyphenols, amino acids, chlorophyll, and carotenoids, while increasing organic acids and sugars. Also catalyzed the synthesis of aromatic compounds like (E)-nerolidol, β-ionone epoxide, and α-farnesene, shaping the floral-fruity aroma and mellow taste of tea.

Pu’er raw tea, a representative tea with a positive correlation between quality and storage time, has a unique aging process. It can not only reduce the heavy astringent taste of newly produced tea, but also has a complex and fragrant aging aroma. However, the extremely slow natural aging process often takes years or even decades for quality transformation, along with the risk of termite infestation, odor absorption, etc. This study found that UV-C irradiation could significantly accelerate the aging process of tea. It enhanced the richness of the aroma, while reducing astringency and creating a smoother and mellower taste. The results of substances analysis revealed an increase in key aroma compounds such as alcohols, aldehydes and terpenes, and a decrease in catechin and caffeine with UV-C irradiation, which is consistent with the natural aging trend. An efficient and safe rapid aging technology of Pu’er raw tea has been successfully established.

The fresh aroma of Longjing tea is vulnerable to unfavorable storage conditions. However, limited research has addressed effective solutions apart from low-temperature storage. This study aimed to investigate the impact of oxygen scavenger on aroma quality of packaged Longjing tea samples at elevated storage temperatures. As a result, the utilization of oxygen scavenger could effectively mitigate aroma deterioration of Longjing tea caused by elevated temperature during storage, resulting in a decrease in the stale odor scores by more than 3.0. The utilization of oxygen scavenger achieved aroma-preserving effect by inhibiting the accumulation of key stale odor compounds and maintaining the levels of volatiles related to freshness aroma. The key volatile contributors to stale odor are primarily ketones and alcohols resulting from thermal carotenoids degradation/lipid oxidation, which exhibit woody or fatty odors. These findings provide essential theoretical principles for improving Longjing tea preservation technology.

Liubao tea (LBT) with longer storage year is believed to have better sensory quality. The aroma characteristics and fungal community succession during the storage process of LBT were studied using LBT stored for 2-15 years as materials. The results showed that the aroma characteristics of LBT showed significant changes in 3 stages. After 10 years of storage, the sensory quality of LBT was notably improved, with herbal aroma beginning to emerge and a distinctly woody aroma. In addition, fungi were involved in the transformation of substances to affect the aroma quality during the storage of LBT. Aspergillus and Penicillium may help reduce musty and green odors and enhancing woody and herbal odors based on correlation analysis. This study provided useful information on the key aroma compounds and core functional microorganisms that drive the aroma characteristics formation of LBT during storage.

INTRODUCTION:Traditionally, the mechanism of dark tea quality formation has centered on microorganisms, with quality regulated by manipulating microorganisms and their fermentation environment. Nevertheless, raw teas, the natural selective medium of microbial community, was completely ignored in the formation of dark tea unique flavors. OBJECTIVES:This study aims to uncover the previously unappreciated interactions between raw tea and microorganisms, demonstrating the significant role of raw tea in the formation of dark tea quality. METHODS:Sun-dried raw tea (SDT), baked raw tea (BT), and pan-fried raw tea (PFT) were pile fermented. Chemical profiles, microbial communities, and sensory qualities were assessed by metabolomics, high-throughput sequencing, and sensory evaluation, with correlation and multiple factor analyses used to explore their relationships. RESULTS:Compared to PFT and BT, SDT had 18 % lower flavonoid content and 26 % lower catechin content, which favored dominant Agathobacter and Wickerhamomyces. Wickerhamomyces contributed to flower aroma by producing alcohols, esters and terpenes, while Agathobacter amplified acid production. The distinctive dominant bacterium Acidovorax in BT was positively correlated with alcohols and hydrocarbons, with Pearson's r > 0.6, resulting in a 47 % increase in volatile alcohol level, enhancing the fresh and refreshing attributes. A 70-80 % increase in iron concentration in PFT compared to SDT and BT resulted in the predominance of Geobacter, which exhibited a negative correlation with aldehydes. The presence of distinctive bacteria, Streptococcus and Ligilactobacillus, in PFT led to a significant rise in volatile acid content, increasing from 5 % to 25 %. CONCLUSION:The chemical profiles of raw tea could reshape local microbiota, which then drives unique qualities of dark tea. This indicates dark tea quality is not passively shaped by the environmental microorganisms, but actively screened by raw tea chemistry. This study paves the way for targeted manipulation of raw tea chemical profiles to achieve desired dark tea flavor characteristics.

Objectives:Asthma is a complex inflammatory disease of the lungs marked by increased infiltration of leukocytes into the airways, which restricts respiratory function. Proliferator-activated receptor-γ coactivator-1 alpha (PGC-1α) has been recognized as an essential immunomodulator and has the potential as a novel anti-inflammatory target in asthma. The current study aims to investigate the functions of PGC-1α in ovalbumin (OVA)-sensitized asthmatic mice and underlying mechanisms. Materials and Methods:BALB/c mouse asthma model was induced by OVA in vivo. The therapeutic effects of PGC-1α agonist (ZLN005) on asthma were assessed by histological and biochemical analysis. In addition, we integrated real-time qPCR, western blotting, and immunofluorescence analysis to reveal the underlying mechanism. Results:In the lung tissue of asthmatic mice, PGC-1α levels were down-regulated. Diff-Quik staining indicated that ZLN005 therapy on asthmatic mice reduced the number of inflammatory cells (eosinophilic granulocytes, neutrophils, lymphocytes, and mononuclear macrophages) in bronchoalveolar lavage fluid (BALF), ameliorated pathologic alterations in lung tissues. ZLN005 alleviated airway structure and inflammation, as well as down-regulating the serum immunoglobulin E (IgE), OVA-specific IgE, and T-helper 2 (Th2) cytokines (interleukin (IL)-4, IL-5, and IL-13) expression. Mechanistically, the results showed that ZLN005, through the NF-κB-p65 axis, prominently inhibited the activation of the NLRP3 inflammasome and reduced the levels of the NLRP3 downstream targets IL-1β and IL-18. Conclusion:PGC-1α agonist (ZLN005) regulated lung inflammation in asthmatic mice by inhibiting the NF-κB-p65/NLRP3 signaling pathway, supporting that ZLN005 may be a candidate for future asthma treatment.

Hei brick tea undergoes a unique "steam pressing-drying (SPD)" process, where the interactions between raw tea chemicals and microbial communities occur, shaping the sensory qualities. Current studies have revealed the sensory attributes and microbial succession process in dark tea, while the correlations and interaction mechanisms between raw tea and dominant fungi during the SPD process are hardly uncovered. In this study, raw dark teas of two cultivars (Jiukeng and Chunyu 2) were applied to the SPD process. The steam pressing and drying provide the same initial microbes and fermentation conditions, respectively. High-throughput sequencing revealed a reduction in microbial diversity and an increase in key fungi like Aspergillus. A strong correlation was found among 28 non-volatile components, 99 volatile flavor contributors and dominant fungi. For instance, gallic acid, caffeine, and GCG were positively associated with the most predominant fugus A. amstelodami, while valine, glutamic acid, γ-aminobutyric acid, alanine, isoleucine, GC, and leucine exhibited negative correlation with A. amstelodami. Simultaneously, A. amstelodami contributed to improving aroma formation through increasing volatile long-chain alcohols, ketones, and acids. The study provides basic data on microbial dynamics and chemical transformations during the SPD process, guiding fermentation optimization for enhanced tea quality.

Consumer preferences for rich flavor drive rapid growth in the new-style tea beverage market ($4.74 billion by 2030). Coffee-tea, a newly emerging product that integrates both coffee and tea flavor by blending process. While holding significant market promise, it faces a critical flavor challenge: burnt bitterness due to high-temperature coffee roasting (∼200 °C) and powerful adsorptive capacity of tea. This study innovatively employed cascaded improvement strategies to coffee white tea, with sensory evaluation and chemical analysis method, to mask burnt bitterness: 1) coffee bean roasting process optimization (220 °C, 12 min) to activated coffee aroma while achieving harmony flavor; 2) scenting process introduction to remove coffee beans that present bitterness; 3) Rooibos blending to mask burnt notes by introducing sweet-floral volatiles (lauric acid, etc.) and preserving key coffee aromas. This synergistic approach achieving burnt flavor masked and flavor balance in coffee-tea, offering a template for new-style tea beverages development.

Focusing on the self-assembly process of black tea infusion nanoparticles helps elucidate the formation mechanism of tea cream. Brewing times ranging from 1 to 10 min were systematically assessed in this study, and the release pattern of the major components of the tea infusion was followed and related to the dynamic changes of the components of the black tea cream. The mean particle size of nanoparticles in the black tea infusion gradually increased with increasing brewing time, reaching a maximum (269.84 +/- 11.25 nm) at 300 s. The results showed that soluble sugars were the most abundant substances of the tea cream at 60 s, and the proportion changed very little during the process. Proteins and flavonoids were rapidly incorporated into the tea cream, maintaining a concentration trend in accordance with the tea infusion. The percentages of caffeine, theobromine, gallic acid, and catechins in tea cream showed a sudden decrease at 240 s, followed by a gradual increase. This formation of tea cream is pH-dependent, with aggregation and precipitation at pH 0-7 and increased dissociation at pH 7-11. The findings will facilitate a more profound comprehension of the formation mechanism of black tea cream.

Liubao insect tea (LIT) is a traditional tea produced from the excreta of Hydrillodes repugnalis that are fed with Liubao tea. In this study, LIT polyphenols (LITP) were extracted and identified, mainly consisting of brevifolin carboxylic acid, brevifolin, ellagic acid. The study aimed to explore the therapeutic potential of LITP in experimental colitis induced by dextran sulfate sodium in mice. LITP treatment effectively mitigated colitis symptoms, including body weight loss, diarrhoea and haematochezia, etc. Furthermore, LITP treatment significantly increased colon length, attenuated inflammatory cell infiltration and mucosal damage, safeguarded the integrity of the epithelial cell barrier, and reduced proinflammatory cytokines levels. Noteworthy alterations in the abundance of gut microbiota community were also observed, with increases in beneficial bacteria Akkermansia, Clostridia_UCG-014, and decreases in harmful bacteria Turicibacter and Erysipelatoclostridium. In conclusion, LITP exerted alleviative effects on colitis via fortifying intestinal barrier and modulating the intestinal microbiota.

Throughout the natural aging process from new to aged white tea, the flavor evolves into a 'stale flavor', despite the initial umami diminishes. The flowering process, inoculation of Eurotium cristatum to white tea, improves the flavor. The impact on sensory qualities and underlying chemical basis of flowering in aged white tea warrant investigation. Sensory analysis, non-targeted metabolomics and volatilomics together deciphered flavor modifications of flowering in aged white tea from different aging years (FAWTs). Findings indicate the flowering process can recover the umami of aged white tea, enhancing the 'stale flavor'. These changes primarily stem from oxidations of catechins and free amino acids, enrichments of flavonols and soluble sugars, and 16 pivotal aroma compounds from degradations of lipids and glycosides. Additionally, 15 volatile and 39 non-volatile compounds were identified as potential biomarkers for FAWTs. These findings offer a viable strategy to improving the quality of aged white tea.