Golden-flower fungus (Eurotiwm Cristatum) presents fungal flower aroma as well as accelerates the aging of white tea (Shoumei).

Golden-flower fungus (Eurotiwm Cristatum, EC) is widely inoculated in dark tea to endow a typical fungal floral aroma. Recently, Golden Flower White Tea (GFWT), prepared by transplanting EC-mediated fermentation to white tea (Shoumei, SM) to reform the roughness and coarseness, has attracted much attention attributed to coordinated flavor. However, the bio-chemistry reactions between EC and SM, along with origination of composited aroma are still unclear. Thus, the rejected EC, GFWT leaves and stems after EC removal were separated by layer-by-layer stripping following sensory evaluation, volatiles and microstructure analysis to uncover aroma formation mechanism. In GFWT, EC presents fungal flower aroma rather than contribution of extracellular enzymes secreted by fungus in Fu brick tea. Moreover, the short "flowering process" (7 days) endows SM with a stale, jujube, and sweet aroma, which is regarded as the typical characteristic of aged white tea. This inspires EC-mediated fermentation as a promising rapid aging process.

Unraveling the contributing factors of stale odor in Longjing tea through a sensomics approach.

Longjing tea is renowned for its fresh aroma and high value. However, during storage, the emergence of an off-flavor known as "stale odor" can significantly impact the flavor quality and economic benefits of Longjing tea. Yet, the specific volatiles responsible for this stale odor in Longjing tea remain unknown. In this study, Longjing tea samples with varying degrees of stale odor intensity were analyzed using simultaneous distillation extraction coupled with gas chromatography-mass spectrometry (SDE-GC-MS). Through odor activity value (OAV) and fractional omission testing, hexanoic acid and trans-2-nonenal were identified as the primary contributors to the stale odor. Moreover, the concentration of hexanoic acid was found to be valuable in predicting the intensity of the stale odor in Longjing tea. The oxidative degradation of linoleic acid was proved as the generation pathway of stale odor in Longjing tea. These findings provide essential theoretical principles for Longjing tea production and preservation.

A systemic review on Liubao tea: A time-honored dark tea with distinctive raw materials, process techniques, chemical profiles, and biological activities.

Liubao tea (LBT) is a unique microbial-fermented tea that boasts a long consumption history spanning 1500 years. Through a specific post-fermentation process, LBT crafted from local tea cultivars in Liubao town Guangxi acquires four distinct traits, namely, vibrant redness, thickness, aging aroma, and purity. The intricate transformations that occur during post-fermentation involve oxidation, degradation, methylation, glycosylation, and so forth, laying the substance foundation for the distinctive sensory traits. Additionally, LBT contains multitudinous bioactive compounds, such as ellagic acid, catechins, polysaccharides, and theabrownins, which contributes to the diverse modulation abilities on oxidative stress, metabolic syndromes, organic damage, and microbiota flora. However, research on LBT is currently scattered, and there is an urgent need for a systematical recapitulation of the manufacturing process, the dominant microorganisms during fermentation, the dynamic chemical alterations, the sensory traits, and the underlying health benefits. In this review, current research progresses on the peculiar tea varieties, the traditional and modern process technologies, the substance basis of sensory traits, and the latent bioactivities of LBT were comprehensively summarized. Furthermore, the present challenges and deficiencies that hinder the development of LBT, and the possible orientations and future perspectives were thoroughly discussed. By far, the productivity and quality of LBT remain restricted due to the reliance on labor and experience, as well as the incomplete understanding of the intricate interactions and underlying mechanisms involved in processing, organoleptic quality, and bioactivities. Consequently, further research is urgently warranted to address these gaps.

Chemometrics-based investigation of non-volatiles/volatiles flavor of tencha (Camellia sinensis cv. Yabukita, Longjing 43 and Baiye 1).

The increasing demand for tea consumption calls for the development of more products with distinct characteristics. The sensory quality of tencha is significantly determined by innate differences among tea cultivars. However, the correlations between the chemical composition and sensory traits of tencha are still unclear. To enhance the understanding of the flavor formation mechanism in tencha and further to develop new cultivars resources, we investigated non-volatiles and volatile metabolites as well as sensory traits in tencha from different tea cultivars (Camellia sinensis cv. Yabukita, Longjing 43 and Baiye 1); the relationships between the flavor traits and non-volatiles/volatiles were further evaluated by partial least squares - discriminate analysis (PLS-DA), multiple factor analysis (MFA) and multidimensional alignment (MDA) analysis. A total of 64 non-volatiles and 116 volatiles were detected in all samples, among which 71 metabolites were identified as key flavor-chemical contributors involving amino acids, flavonol glycosides, flavones, catechins, ketones, alcohols, hydrocarbons, aldehydes, esters and acids. The levels of taste-related amino acids, flavonol glycosides and gallic acid varied significantly among the tencha samples made from different tea cultivars. All the samples exhibited typical quality characteristics of tencha. The tencha from Camellia sinensis cv. Longjing 43 and Camellia sinensis cv. Baiye 1 (cultivated in the open) exhibited higher levels of amino acids and gallic acid, which were associated with the umami taste and mellow taste of tea infusion. Abundant flavonol glycosides were related to the astringency, while partial tri-glycosides specifically quercetin-3-O-galactoside-rhamnoside-glucoside and total of flavonol galactoside-rhamnoside-glucoside were associated with mellow taste. The floral alcohols were identified as significant contributors to the refreshing aroma traits of tencha. The green, almond-like, acidic and fruity odorants were associated with a green and fresh aroma, while the green, cheesy and waxy odorants such as ketones, esters, acids and hydrocarbons were associated with seaweed-like aroma. This study provides insight into sensory-related chemical profiles of tencha from different tea cultivars, supplying valuable information on flavor and quality identification for tencha.

Epigallocatechin gallate (EGCG) alleviates the inflammatory response and recovers oral microbiota in acetic acid-induced oral inflammation mice.

The oral microbiota, the second largest microbiome in the human body, plays an integral role in maintaining both the local oral and systemic health of the host. Oral microecological imbalances have been identified as a potential risk factor for numerous oral and systemic diseases. As a representative component of tea, epigallocatechin gallate (EGCG) has demonstrated inhibitory effects on most pathogens in single-microbial models. In this study, the regulatory effect of EGCG on more complex oral microbial systems was further explored through a mouse model of acetic acid-induced oral inflammation. Acetic acid induces histological damage in the cheek pouch, tongue, and throat, such as broken mucosa, submucosal edema, and muscular disorders. These detrimental effects were ameliorated significantly following EGCG treatment. Additionally, EGCG reduced the levels of the inflammatory cytokines interleukin-6 and tumor necrosis factor-α to alleviate the inflammation of the tongue, cheek pouch, and throat. According to the 16S rDNA gene sequencing data, EGCG treatment contributed to increased diversity of the oral microbiota and the reversal of oral microecological disorder. This study demonstrates the regulatory effect of EGCG on dysregulated oral microbiota, providing a potential option for the prevention and treatment of oral-microbiota-associated diseases.

Green tea extracts alleviate acetic acid-induced oral inflammation and reconstruct oral microbial balance in mice.

Oral cavity contains the second largest microbial community in the human body. Due to the highly vascularized feature of mouth, oral microbes could directly access the bloodstream and affect the host healthy systemically. The imbalance of oral microbiota is closely related to various oral and systemic diseases. Green tea extracts (GTE) mainly contain tea polyphenols, alkaloids, amino acid, flavones, and so on, which equipped with excellent anti-inflammatory activities. Previous studies have demonstrated the beneficial effects of GTE on oral health. However, most researches used in vitro models or focused on limited microorganisms. In this study, the regulatory effect of GTE on oral microbiome and the alleviative effect on oral inflammation in vivo were evaluated. The results showed that GTE could efficiently alleviate the inflammations of the tongue, cheek pouch, as well as throat. GTE effectively inhibited the activation of NF-κB through the upregulation of the anti-inflammatory cytokine interleukin (IL)-10, consequently leading to reduced expression of pro-inflammatory cytokines IL-6 and tumor necrosis factor-α. The indexes of spleen and thymus were also elevated by GTE in stomatitis mice. Moreover, GTE promoted the growth of probiotics Lactobacillus and Bacillus, inhibited the reproduction of pathogens Achromobacter, reversing the microbiota disorders in oral cavity. This study not only presents a novel approach for enhancing oral microecology but also facilitates the wider adoption of tea consumption.

Another thread to uncover the aging mystery of white tea: Focusing on the natural nanoparticles in tea infusion.

Aged white tea (WT) has promising medicinal potential, but how to accurately identify aged white tea is still a difficult problem. Inspired by tea cream, the relationship between the characteristics of nanoparticles in tea infusion and aging time was studied. The results showed that with the increase of aging time, the particle size of white tea nanoparticles (WTNs) decreased gradually. Microscopic images showed that the surface structure of WTNs was changed in three aspects: the waxy layer, the cuticle layer and the palisade tissue. Additional in vitro modeling demonstrated a strong correlation between nanoparticle size and protein and tea polyphenol content. The correlation between nanoparticle sizes and aging time was further verified in aged Pu'er raw tea. Starting with the tea infusion's nanoparticles, this study showed that the aging time of WT would impact the nanoparticles' properties, offering a unique way to determine the aging period of WT.

A local dark tea - Liubao tea - extract exhibits remarkable performance in oral tissue regeneration, inflammation relief and oral microbiota reconstruction.

The prevalence of oral health problems is ubiquitous in contemporary society, with particular emphasis placed on the central role of oral flora in mitigating this issue. Both ancient literature and modern research have highlighted the promising application of tea with substantial bioactive properties, particularly dark tea, in preserving and promoting oral health. Liubao tea, a widely consumed dark tea with increasing popularity in recent years, has been reported to possess abundant bioactive constituents, exhibit remarkable antioxidant and anti-inflammatory effects, modulate the flora structure and so on. It may be a promising candidate for addressing oral health problems. In this study, Liubao tea was meticulously extracted, purified and identified, followed by an investigation of its potential to modulate oral microecology by virtue of an acetic acid-induced oral disorder murine model. The results revealed that Liubao tea extract (LTE) application commendably reconstructed the oral mucosal barrier, promoted tissue regeneration and mitigated micro-inflammation. Furthermore, LTE treatment could also ameliorate the oral flora composition by decreasing the abundance of Proteobacteria and increasing the abundance of Firmicutes and Actinobacteria at the phylum level, as well as inhibiting pernicious bacteria such as Streptococcus and Delftia acidovorans. So, it could promote the generation of a beneficial microenvironment and regulate the immune process. Overall, LTE demonstrated remarkable potential in regulating the balance of oral microecology, suggesting that it may represent a promising therapeutic strategy for oral health concerns.

Yellow tea: more than turning green leaves to yellow.

Yellow tea (YT), a slightly-fermented tea originated from Ming Dynasty with distinctive "Three yellows," mild-sweet smell, and mellow taste attributed to the unique yellowing process. Based on current literature and our previous work, we aim to comprehensively illustrate the key processing procedures, characteristic chemical compounds, health benefits and applications, as well as the interlocking relationships among them. Yellowing is the most vital procedure anchored on the organoleptic quality, characteristic chemical components, and bioactivities of YT, which is influenced by temperature, moisture content, duration, and ventilation conditions. Pheophorbides, carotenoids, thearubigins and theabrownins are the major pigments contributing to the "three yellows" appearance. Alcohols, such as terpinol and nerol, are attributed to the refreshing and sweet aroma of bud and small-leaf YT, while heterocyclics and aromatics forming during roasting result in the crispy rice-like large-leaf YT. Hygrothermal effects and enzymatic reactions during yellowing result in the decline of astringent substances. Meanwhile, multiple bioactive compounds such as catechins, ellagitannins, and vitexin, endow YT with antioxidant, anti-metabolic syndrome, anti-cancer, gut microbiota regulation, and organ injury protection effects. Future studies focusing on the standard yellowing process technology, quality evaluation system, and functional factors and mechanisms, possible orientations, and perspectives are guaranteed.

Hydroxyls on the B ring and gallic acyl are essential for catechins to restrain ADP-induced thrombosis.

Platelet hyperactivation could lead to various cardiovascular and cerebrovascular diseases, while epidemiological analyses have found that long-term tea drinking could prevent and restrain cardiovascular diseases. Existing studies have shown that catechins, especially epigallocatechin gallate (EGCG), are the main functional factors of tea in alleviating thrombosis, which could inhibit arterial thrombosis and platelet aggregation induced by a variety of agonists. However, their structure-activity relationship and the underlying mechanisms are still unclear. Based on the above background, this study took six typical catechins as research objects, constructed platelet activation models with different inducers, and explored the inhibitory effects and potential mechanisms of catechins with different structures on platelet aggregation through flow cytometry, immunoblotting, cell spreading, and other experiments. It was found that ester catechins could inhibit platelet aggregation induced by adenosine diphosphate (ADP), while epigallocatechin (EGC) with three hydroxyls on the B ring in non-ester catechins was also able to effectively inhibit platelet aggregation. Our data suggested that gallic acyl on the C ring and three hydroxyls on the B ring were the main functional groups affecting the antithrombotic effect of catechins, and the effect of gallic acyl on platelets was significantly stronger than that of the hydroxyl.

Theaflavin: a natural candidate to restrain thrombosis.

Many clinical studies have demonstrated the beneficial effects of black tea on cardiovascular diseases. However, the antiplatelet and antithrombotic activities of theaflavin (TF-1) remain unknown. In this study, we aimed to investigate the beneficial effects of TF-1 on platelet activation and thrombosis formation both in vitro and in vivo. Firstly, the in vitro antiplatelet activity of TF-1 was analyzed using platelets isolated from human blood via aggregometry, flow cytometry, the ELISA kit, western blot and fluorescence microscopy. Subsequently, the in vivo analysis of the hemostatic state and thrombosis formation was carried out in C57BL/6 mice based on the tail bleeding time and an FeCl3-induced arterial thrombus model. The results showed that TF-1 could prominently inhibit platelet aggregation in a dose-dependent manner, and attenuate P-selectin expression, fibrinogen binding, spreading and thromboxane A2 (TxA2) formation. Western blot analysis showed that TF-1 potently inhibited spleen tyrosine kinase (Syk) and Akt (ser473/474) phosphorylation. The in vivo data further confirmed the inhibition of platelet activation by TF-1 with a prolonged arterial occlusion time (from 15.0 ± 1.1 minutes to 40.0 ± 5.4 minutes). All the results indicated that TF-1 is a powerful inhibitor of platelet activation and thrombosis formation in C57BL/6 mice, and could be developed as a novel food-based inhibitor of thrombotic disorders.

Another perspective to explain green tea cream: Utilizing engineered catechin-caffeine complex.

Green tea cream, the precipitate formed in cooled green tea infusion, appears a negative effect on flavor. To explain the mechanism of green tea cream, complexations between four catechins (CATs) and caffeine (CAF) were engineered and characterized. Dynamic light scattering, high performance liquid chromatography, scanning electron microscopy, fourier-transform infrared spectroscopy, UV-visible absorption spectrum, and x-ray diffraction were used to reveal the differences between ester catechins and non-ester catechins in the dynamic complexation process, particle shape, and precipitate mechanism with caffeine. The results indicated that CATs and CAF affected each other's microenvironment in aqueous solution and Guanidine hydrochloride (GH) weakened the effect both in solution and precipitate. In addition, the 1:1 complex structure of EGC-CAF was first proved, the hydrogen bond, CH…π and π…π interaction were the forces of CAT-CAF complexes by XRD. These results provided a new perspective to the mechanism analysis of green tea cream.

Construction of Sensory/Mass Spectrometry Feedback Platform for Seeking Aroma Contributors during the Aroma Enhancement of Congou Black Tea.

Baking is widely accepted for aroma enhancement of black tea, and studies have mainly focused on the aroma or chemical substances under a specified baking condition. Understanding of the feedback between aroma substances and characteristics is urgently needed. Therefore, a mutual feedback platform (SES/MS) combined sensory evaluation system (SES) with gas chromatography-mass spectrometry (GC-MS) was established. Based on this platform, we found that baking at 90 °C for 4 h or 5 h could maintain the primary aroma attributes and increase characteristic aroma attributes-these were considered to be the best baking conditions for Yunnan congou black tea. Meanwhile, 47 volatiles were identified, among which, pyrrole and benzaldehyde appeared to have a caramel aroma, and 2-furanmethanol and α-terpineol presented a baked aroma. This study reveals the dynamic change of aroma profiles and compounds during the aroma enhancement, and provides an optional template for researchers, focused on the relationship between quality and aroma attributes of teas.

How to Improve the Cognitive Health of Middle-Aged and Elderly People: Evidence From China Family Panel Studies.

In the context of the rapid development of the internet and the increasing severity of the aging problem, and in order to promote aged health and help construct a healthy society. We use micro survey data from the 2016 China Family Panel Studies (CFPS) to investigate the impact of the internet on the cognitive health of middle-aged and elderly people (those aged 40 and above). The robust results suggest that the internet plays a significant positive role in the cognitive health of middle-aged and elderly people in terms of internet use and internet involvement. This effect does not change significantly with differences in gender, household registration, location, or household composition, but there are heterogeneity effects due to differences in education. Further analysis indicates that the satisfaction of emotional attachment with children is the internal mechanism of the internet's influence on the cognitive health of people in this age group. Our paper both help scholars and the public to better understand the impact of the internet on the cognitive health of middle-aged and elderly people and clarifies different methods of defining the internet.

Effect of Yellowing Duration on the Chemical Profile of Yellow Tea and the Associations with Sensory Traits.

The yellowing process is the crucial step to form the characteristic sensory and chemical properties of yellow tea. To investigate the chemical changes and the associations with sensory traits during yellowing, yellow teas with different yellowing times (0-13 h) were prepared for sensory evaluation and chemical analysis. The intensities of umami and green-tea aroma were reduced whereas sweet taste, mellow taste and sweet aroma were increased under long-term yellowing treatment. A total of 230 chemical constituents were determined, among which 25 non-volatiles and 42 volatiles were the key chemical contributors to sensory traits based on orthogonal partial least squares discrimination analysis (OPLS-DA), multiple factor analysis (MFA) and multidimensional alignment (MDA) analysis. The decrease in catechins, flavonol glycosides and caffeine and the increase in certain amino acids contributed to the elevated sweet taste and mellow taste. The sweet, woody and herbal odorants and the fermented and fatty odorants were the key contributors to the characteristic sensory feature of yellow tea with sweet aroma and over-oxidation aroma, including 7 ketones, 5 alcohols, 1 aldehyde, 5 acids, 4 esters, 5 hydrocarbons, 1 phenolic compound and 1 sulfocompound. This study reveals the sensory trait-related chemical changes in the yellowing process of tea, which provides a theoretical basis for the optimization of the yellowing process and quality control of yellow tea.

How Does House Demolition Affect Family Conspicuous Consumption?

Family conspicuous consumption behavior is affected by many factors. Existing pieces of literature seldom focus on the impact of house demolition on family conspicuous consumption and its underlying mechanism. Based on the mental accounting theory and conservation of resources theory, this study uses the micro-data of the 2011 China Household Finance Survey to empirically examine the relationship between house demolition and family conspicuous consumption. Robustness results suggest that house demolition positively affects household conspicuous consumption, which is not only reflected in the overall consumption level but also in the level of average consumption. Further analysis finds that household wealth and materialism value have a significant positive moderating effect on the relationship of the main effect. In addition, in order to clarify the relationship between conspicuous consumption and luxury consumption, this study finds that conspicuous consumption and luxury consumption are not completely equivalent through in-depth theoretical analysis and exploratory investigation. There are similarities in both consumption motivation and pattern, but with differences on consumer subject and object. The contribution of this research is to enrich the theory of decision-making in consumer behavior, which also has certain significance in deepening the understanding of the relationship between conspicuous consumption and luxury consumption.

Validity of SOFA score as a prognostic tool for critically ill elderly patients with acute infective endocarditis.

The prognostic value of the sequential organ failure assessment (SOFA) score for critically ill elderly patients with acute infective endocarditis (IE) remains unknown. From January 2015 to December 2019, 111 elderly (≥65 years) patients with acute IE were consecutively included and divided into a low SOFA (<6) group (n = 71) and a high SOFA (≥6) group (n = 40). Endpoints included in-hospital and long-term (12-36 month) mortality. A high SOFA score was related to higher incidence of in-hospital mortality (30.0%) with an area under the curve (AUC) of 0.796. In multivariate analysis, age [odds ratio (OR) = 2.21, 95% confidence intervals (CI), 1.16-6.79, p = 0.040], SOFA ≥6 (OR = 6.38, 95% CI, 1.80-16.89, p = 0.004) and surgical treatment (OR = 0.21, 95% CI, 0.05-0.80, p = 0.021) were predictive of in-hospital mortality. A Cox proportional-hazards model identified age [Hazard ratios (HR)= 2.85, 95% CI, 1.11-7.37, p = 0.031], diabetes mellitus (HR = 3.99, 95% CI, 1.35-11.80, p = 0.013), SOFA ≥6 (OR = 3.38, 95% CI, 1.26-9.08, p = 0.001) and surgical treatment (HR = 0.24, 95% CI, 0.08-0.68, p = 0.021) as predictors of long-term mortality. A high SOFA score predicts a poor outcome including in-hospital and long-term mortality in critically ill elderly patients with acute IE.

Widely targeted metabolomics analysis of white peony teas with different storage time and association with sensory attributes.

The sensory features of white peony teas (WPTs) significantly change with storage age; however, their comprehensive associations with composition are still unclear. This study aimed to clarify the sensory quality-related chemical changes in WPTs during storage. Liquid chromatography-tandem mass spectrometry based on widely targeted metabolomics analysis was performed on WPTs of 1-13 years storage ages. Weighted gene co-expression network analysis (WGCNA) was used to correlate metabolites with sensory traits including color difference values and taste attributes. 323 sensory trait-related metabolites were obtained from six key modules via WGCNA, verified by multiple factor analysis. The decline and transformation of abundant flavonoids, tannins and amino acids were related to the reduced astringency, umami and increased browning of tea infusions. In contrast, the total contents of phenolic acids and organic acids increased with storage. This study provides a high-throughput method for the association of chemical compounds with various sensory traits of foods.

How does rising housing price affect the health of middle-aged and elderly people? The complementary mediators of social status seeking and competitive saving motive.

Under the backdrop of China's aging population and continuous rising housing price and base on theories pertaining to social status seeking, marriage matching and intergenerational family relationships, use the 2010 and 2014 CFPS national survey micro data, we examine the impact of rising housing price on the health of middle-aged and elderly people and the underlying mechanisms. Rising housing price has a significant negative impact on the health of middle-aged and elderly people, and this effect is also reflected in their physical health, mental acuity and emotional well-being. The internal mechanism is that social status seeking motivation plays a significant mediator role. Through further analysis, we find that competitive saving motive is another intermediate mechanism that causes rising housing price to affect the health of middle-aged and elderly people; it is complementary to the social status seeking motivation. What's more, the mediation effect of the competitive saving motive is notably heterogeneous, as it exists only for middle-aged and elderly people with male or noncollege educated child but does not exist for those with female or college educated child.

Discrimination of white teas produced from fresh leaves with different maturity by near-infrared spectroscopy.

White tea is a special tea product with increasing market demand. The assessment of white tea quality is mainly based on panel sensory by sensory evaluation experts, which is time costly and is limited by many uncertainties. This study established a rapid and accurate method for classification of white teas produced from buds and young leaves and that produced from mature leaves and shoots using near-infrared spectroscopy (NIR). Back propagation neural network modelling and support vector machine (SVM) modelling were compared with six pre-processing methods. The best performance was provided by SVM with particle swarm optimization combined with Savitzky-Golay filter pre-processing method, achieving the accuracy of 98.92% in test samples. The NIR-related chemical compounds of two categories of white teas produced from fresh leaves with different maturity were analyzed, including catechins, alkaloids, amino acids and flavonol glycosides. Compared with chemical component concentration, NIR absorbance had a distinct advantage in quick classification of white teas based on the principal components analysis. In addition, the sensory characteristics of two categories white teas produced from fresh leaves with different maturity were also assessed by panelist. The result showed that characteristics of "umami-like" and "smooth" were more likely present in white teas produced from buds and young leaves, while "woody" and "coarse" characteristics were usually present in white teas produced from mature leaves and shoots. Thus, NIR technique is a rapid and reliable method for discrimination of white teas produced from fresh leaves with different maturity, and is a potential method to discriminate sensory characteristics of white teas.