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Monascus is a filamentous fungus with a long history of application in China, which can produce a variety of secondary metabolites, including Monascus red pigments, Monascus orange pigments, Monascus yellow pigments, and citrinin. There is widespread attention being paid to natural pigments because of their safety. Among the many natural pigments, orange pigment has a wide range of applications because of its unique color, but current production levels in the orange pigment industry are limited to a certain extent due to the insufficiently wide range of sources and low production. In this study, the ARTP mutation was used to obtain a strain with high-yield orange pigment and low citrinin. The strain RS7 was obtained through two-step mutagenesis, and all three pigments were improved to different degrees. The color value of orange pigment was elevated from the original 108 U/mL to 180 U/mL, an increase of 66.7% compared to the original strain, and the citrinin content was reduced by 69%. The result of microscopic morphology showed that RS7 has more wrinkles and is more convex than the R1 strain, but there was little change between the two strains. Therefore, the ARTP mutation influenced the growth and the biosynthesis of pigments in Monascus. In addition, the conditions of ultrasonic extraction of Monascus pigments were optimized using the response surface, and the separation of pigments was achieved with the method of thin-layer chromatography. Pigment stability results showed that the temperature had no significant effect on orange pigment, while tea polyphenol could improve its stability. This study generated a strain with high-yielding orange pigment and could lay a foundation for the future application of Monascus orange pigment in the food industry. Full article

During the process of flue-curing and processing, leaves from cash crops such as tea and tobacco frequently undergo a phenomenon of browning, leading to reduced quality and significant economic losses. Despite a variety of approaches developed to suppress browning, little is known about the role that flue-curing of postharvest leaves with stems plays in delaying browning. This study investigated the impact of leaf-with-stem (LWS) flue-curing on the browning of tobacco and its underlying mechanisms. Physiological results indicated that LWS flue-curing effectively delayed browning by enhancing antioxidant capacity and maintaining reactive oxygen species (ROS) levels during the yellowing stage. Comprehensive transcriptome and metabolome analyses showed that LWS flue-curing significantly influenced various metabolic pathways. Specifically, 196, 218, and 402 metabolites, and 65, 131, and 718 genes exhibited significant changes at the 38 °C, 40 °C, and 42 °C stages, respectively, inhibiting membrane lipid degradation and enhancing the supply of reducing hydrogen through the oxidative pentose-phosphate pathway. Additionally, hormone signaling pathways were found to be associated with LWS flue-curing. These findings highlight the complex interplay of metabolic pathways and signaling networks in attenuating browning, providing valuable insights for minimizing postharvest leaf browning during flue-curing and processing. Full article

In this study, environmentally friendly and low-cost biomass materials were selected as wood flame retardants. Three polyelectrolyte flame-retardant coatings made from chitosan (CS), tea polyphenols (TP), soybean isolate protein (SPI), and banana peel powder (BBP) were constructed on wood surfaces by layer-by-layer (LBL) self-assembly. The results of SEM-EDS and FT-IR analyses confirmed the successful deposition of CS-TP, CS-SPI, and CS-BPP on the wood surface, and the content of N element increased. The TG results showed that the initial decomposition temperature and the maximum thermal decomposition temperature of the coated wood specimens decreased, while the char residue increased significantly. This is due to the earlier pyrolysis of CS-TP, CS-SPI, and CS-BBP. This shows that the three polyelectrolyte flame-retardant coatings can improve the thermal stability of wood. The combustion behavior of the wood specimen was observed by exposure to combustion; the coated wood could self-extinguish within a certain period of time after ignition, and the flame-retardant performance was improved to a certain extent. SEM and EDS characterization analyses of the carbon residue after combustion showed that the coated wood charcoal layer was denser, which could effectively block heat and combustible gas. Full article

Since the last century, it has been shown that dedifferentiated cells of Camellia sinensis can produce catechins and other secondary metabolites under in vitro conditions, with potential applications in the cosmetic, pharmaceutical and food industries. In this work, cell suspension cultures of a C. sinensis cell line (LSC-5Y) were established in a liquid medium in order to optimize the biomass productivity, catechin monomer (GC, EGC, C, EC, CG, and ECG) and alkaloid (TB and CAF) productivity. The following factors were evaluated: concentration of growth regulators (BA and IBA), inoculum size, age of the cell line, light exposure, and effect of biotic elicitors (MeJA and extracts of Ciborinia camelliae). GC, EGC, and ECG increased approximately 1.80-fold when the auxin IBA concentration was increased from 0.1 to 2.0 mg/L. In addition, better productivity of EGC, C, EC, and CAF was achieved by using inoculum densities between 50 and 100 g/L. Although lower inoculum densities (25 g/L) showed a higher growth rate (0.20 d⁻¹), the use of inoculum densities higher than 25 g/L favors a 2–4-fold increase in total catechin (TC) productivity, with maximum productivity being reached after 21 days of culture. However, the cell line showed instability in TC productivity: in the short term (in three successive subcultures), the coefficient of variation was 32.80%, and catechin production capacity was 2.5 years with maximum productivity at 0.5 years. Finally, it was observed that ethanol, used as an elicitor solvent, has a strong elicitor effect capable of increasing the accumulation of catechins up to 5.24 times compared to the treatment without an elicitor. Full article

Cold stress causes considerable damage to tender tea seedlings. Previous studies have explored changes in the physiological and biochemical factors of tea in response to cold stress; however, the mechanisms of cold resistance in ancient tea tree plants are unclear. The aim of this study was to analyze the effects of 0 °C cold stress for 15 days and 24 °C ambient temperature recovery for 5 days on the physiological and biochemical characteristics of two representative old tea varieties: Dali tea and Siqiu tea. The results revealed significant changes in antioxidant, photosynthetic efficiency, and physiological and biochemical indicators in response to cold stress, with the two species exhibiting different patterns. Cold stress decreased chlorophyll and carotene content, F_v/F_m, Y_(II), non-photochemical quenching coefficient, photochemical quenching, and superoxide dismutase (SOD) activity, and increased intercellular CO₂ concentration and ascorbate peroxidase activity. Siqiu tea showed a higher increase in soluble sugar content and antioxidant enzyme activity and a lower accumulation of malondialdehyde and minimal fluorescence (F₀) than Dali, indicating a greater tolerance to cold stress. Based on partial least-squares discriminant analysis, six key differential physiological indicators of cold resistance—water-soluble sugar, F₀, peroxidase, catalase, SOD, and gas conductance—were identified. Our findings provide technical support for identifying ways to protect ancient tea trees from extreme weather conditions. Full article

This study explores the diffusion of innovative tea products in the Chinese market, examining the shift from traditional tea consumption toward “new tea” products characterized by convenience, variety, and alignment with contemporary consumer preferences. Using a structured questionnaire, data were collected from 543 participants and analyzed through factor-cluster analysis to segment consumers based on their innovation adoption behavior. The results indicate that younger, educated, and higher-income groups adopt new tea innovations more rapidly. Notably, early adopters, representing over half of the consumer base, are not frequent consumers of these beverages, compelling suppliers to continually innovate to maintain long-term revenue growth. This study contributes to the literature by highlighting the influence of sociodemographic factors on adoption rates and offering strategic marketing insights to enhance the uptake of new tea products. These findings underscore the importance of targeting demographic segments effectively and addressing the unique consumption patterns of early adopters to drive sustained market growth. Full article

Polymer modification has been established as a cost-effective, simple, in situ method for overcoming some of the inherent disadvantages of boron-doped diamond (BDD) electrodes, and its application has been extended to reliable, low-cost environmental monitoring solutions. The present review focuses on modifying BDD electrodes with semi-conductive polymers acting as redox mediators. This article reports on the development of a 3-methyl thiophene-modified boron-doped diamond (BDD/P3MT) sensor for the electrochemical determination of total phenolic compounds (TPCs) in tea samples, using gallic acid (GA) as a marker. GA is a significant polyphenol with various biological activities, making its quantification crucial. Thus, a simple, fast, and sensitive GA sensor was fabricated using the electroanalytical square wave voltammetry (SWV) technique. The sensor utilizes a semi-conductive polymer, 3-methyl thiophene, as a redox mediator to enhance BDD’s sensitivity and selectivity. Electrochemical synthesis was used for polymer deposition, allowing for greater purity and avoiding solubility problems. The BDD/P3MT sensor exhibits good electrochemical properties, including rapid charge transfer and a large electrochemical area, enabling GA detection with a limit of detection of 11 mg/L. The sensor’s response was correlated with TPCs measured by the Folin–Ciocalteu method. Square wave voltammetry (SWV) showed a good linear relationship between peak currents and GA concentrations in a wide linear range of 3–71 mg/L under optimal conditions. The BDD/P3MT sensor accurately measured TPCs in green tea, rooibos tea, and black tea samples, with green tea exhibiting the highest TPC levels. The results demonstrate the potential of the modified BDD electrode for the rapid and accurate detection of phenolic compounds in tea, with implications for quality control and antioxidant activity assessments. The prolific publications of the past decade have established BDD electrodes as robust BDD sensors for quantifying polyphenols. Fruits, vegetables, nuts, plant-derived beverages such as tea and wine, traditional Eastern remedies and various herbal nutritional supplements contain phenolic chemicals. The safety concerns of contaminated food intake are significant health concerns worldwide, as there exists a critical nexus between food safety, nutrition, and food security. It has been well established that green tea polyphenol consumption promotes positive health effects. Despite their potential benefits, consuming high amounts of these polyphenols has sparked debate due to concerns over potential negative consequences. Full article

A simple sensor for the quantitation of tryptophan (Trp) has been developed using a glassy carbon electrode (GCE) modified with electro-synthesized carbon dots functionalized with glycine (Gly@CDs). The surface functionalization with an amino acid led to the formation of large clusters of nanostructures. To our knowledge, this is the first study in which a Gly@CDs clusters modified GCE is used for the analysis of Trp. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) are the techniques used to study Trp electrochemical behavior in an alkaline solution using such an electrode. A linear concentration range was found for Trp from 5 × 10⁻⁶ to 5 × 10⁻³ mol L⁻¹ with a detection limit (LOD) of 5 × 10⁻⁶ mol L⁻¹. The reproducibility and repeatability data were satisfactory in terms of RSD%. Moreover, the stability during the time of the modified electrode was considered, evidencing interesting results. The described sensor was used for the determination of Trp in herbal tea and a dietary supplement, and the results were compared with those obtained with HPLC-ESI-MS in the Selected Ion Recording (SIR) mode as an independent method. The electrochemical sensor presents significant advantages in terms of low cost, portability, ease of handling and not requiring skilled personnel. Full article

One of the main reasons for the low yield of Camellia oleifera Abel is the large number of flowers and fruits that fall off before ripening. The aim of this study was to investigate the effect of foliar spraying of potassium dihydrogen phosphate (KH₂PO₄) on the fruiting characteristics of C. oleifera, and to provide technical support for its flower and fruit preservation and yield increasing. Three C. oleifera cultivars, ‘Changlin 18’, ‘Changlin 166’, and ‘Changlin 40’, were used as experimental materials to conduct foliar spraying experiments with different water concentrations of KH₂PO₄. The effects of KH₂PO₄ on the fruit retention rate, fruit properties, and seed oil quality of each cultivar were measured and analyzed. The application of the optimal concentration of KH₂PO₄ significantly enhanced various fruit quality metrics of three C. oleifera cultivars. Specifically, the total fruit retention rate was increased by 30.02~87.53%, the transverse diameter by 7.36~21.21%, and the longitudinal diameter by 18.56%, and the fruit weight of ‘Changlin 40’ could increase by 83.63%. It also increased dry seed yield by 27.87~80.81%, dry kernel rate by 10.29~30.12%, dry seed oil content by 28.00~29.77%, total unsaturated fatty acids (TUFAs) by 0.63~5.3%, monounsaturated fatty acids (MUFAs) by 0.30~5.37%, and squalene by 0.09~0.14% during the maturing stage. However, camellia cultivars had the different responses to KH₂PO₄ concentrations. To promote the fruiting of C. oleifera, improve the economic traits of fruits, and enhance the quality of tea oil, the recommended concentrations of KH₂PO₄ solution are 4.50 g·L⁻¹, 1.50 g·L⁻¹, and 1.50 g·L⁻¹, for mist spraying on the trees of ‘Changlin 18’, ‘Changlin 166’, and ‘Changlin 40’, respectively. For mixed cultivars of C. oleifera which planted randomly, the recommended concentration range of KH₂PO₄ solution for spraying is 1.50 to 4.50 g·L⁻¹. Full article

Paris polyphylla Smith var. Chinensis (Franch.) Hara is a medicinal plant that belongs to the Liliaceae family. Its main components are parissaponins, which have excellent medicinal effects such as anti-inflammatory, anti-tumor, etc. Improving the quality of parissaponins through artificial directional regulation has emerged as a practice to meet medical demand and is a new research hotspot. In this paper, P. polyphylla plants were treated with UVA, UVB, and UVC, and the contents of PolyPhyllin VI (PPVI) and PolyPhyllin VII (PPVII), saponin synthase (squalene synthase, SS; cycloartenol synthase, CAS; cytochrome P450, CYP450; and glycosyl transferases, GT) activity, MDA, and the photosynthetic pigment indexes were measured and analyzed. The results showed that PPVII content increased by 32.43% with UVC treatment after 4 h (3.43 mg/g), but the PPVI and PPVII contents in the other groups decreased compared with CK (control group) and they did not return to the original level after 4 h. SS, CAS, CYP450, and GT synthases were activated in varying degrees via UV treatment and increased, respectively, by 22.93%, 10.83%, 20.15%, and 25.98%. Among them, GT, as the last of the synthetases, had a shorter response time to UVB (30 min) and UVC (15 min); the difference was sensible compared with CK. Moreover, UV had a stressing effect and promoted the rapid accumulation of MDA content (increased 17.66%, 34.53%, and 9.65%) and carotenoid (increased 7.58, 5.60, and 7.76 times) within 4 h compared to CK. UVB and UVC radiation visibly improved chlorophyll a content (42.56% and 35.45%), but UVA did not, and the change in chlorophyll b content showed no overt statistical difference. In addition, PPVI and PPVII were negatively correlated with SS, CAS, carotenoids, and MDA (p < 0.05) and positively correlated with CYP450, GT, and chlorophyll a (p < 0.05). This study provides a theoretical basis for using UV light to regulate secondary metabolism in P. polyphylla, which is of great value for production management. Full article

The roughness of woven fabric surface has so far been mainly investigated as a key characteristic of comfort in contact with the skin. The analysis of roughness can be extended to various contexts and applications, becoming an important tool for understanding how textile materials react in interaction with different finishing agents, as well as for gaining insight into the durability and effectiveness of treatments. This research presents a comprehensive study on the impact of alkaline hydrolysis and chitosan coating on the roughness of polyester woven fabric, utilizing both novel and adapted methods. The study employed contact and optical methods to analyze fabric and fiber surface characteristics, highlighting the significance of roughness profile parameters in understanding material changes post-treatment. The investigation revealed that mechanical action, alkaline medium, washing temperature, and detergent residues contribute to fabric erosion and modification during washing, with chitosan coatings creating pronounced surface irregularities. Comparative analysis showed significant fabric roughness changes post-washing, while fiber roughness changes were treatment specific. Despite initial increases in fiber roughness due to treatments, their durability decreased after washing. These findings emphasize the importance of roughness analysis in optimizing textile finishing processes and washing cycles, impacting both comfort and treatment efficacy. Full article

Aging is an irreversible pathophysiological process for all organisms. The accumulation of senescent cells in pathological sites or tissues is recognized as the major cause of diseases and disorders during the aging process. Small molecules that reduce senescent cell burdens have gained increasing attention as promising intervention therapeutics against aging, but effective anti-senescence agents remain rare. Camellia Sect. Chrysantha Chang is documented as a traditional Chinese herbal medicine used by ethnic groups for many medical and health benefits, but its effect on aging is unclear. Here, we investigated the anti-senescence potential of eight C. Sect. Chrysantha Chang species. The results show that ethyl acetate fractions from these C. Sect. Chrysantha Chang species were able to delay the senescence of H9c2 cardiomyocytes except for C. pingguoensis (CPg). N-butanol fractions of C. multipetala (CM), C. petelotii var. grandiflora (CPt), and C. longzhouensis (CL) showed a senescent cell clearance effect by altering the expression levels of senescent-associated marker genes in the DNA-damage response (DDR) pathway and the senescent cell anti-apoptotic pathway (SCAPs). By using UPLC-QTOF-MS-based non-targeted metabolomics analyses, 27 metabolites from Sect. Chrysantha species were putatively identified. Among them, high levels of sanchakasaponin C and D in CM, CPt, and CL were recognized as the key bioactive compounds responsible for senescent cell clearance. This study is the first to disclose and compare the anti-cell-senescence effect of a group of C. Sect. Chrysantha Chang, including some rare species. The combination of senescent markers and metabolomics analyses helped us to reveal the differences in chemical constituents that target senescent cells. Significantly, contrary to the C. chrysantha var. longistyla (CCL), which is widely cultivated and commercialized for tea drinks, CM, CPt, and CL contain unique chemicals for managing aging and aging-related diseases. The results from this study provide a foundation for species selection in developing small-molecule-based drugs to alleviate diseases and age-related dysfunctions and may potentially be useful for advancing geroscience research. Full article

Cloud point extraction (CPE) has emerged as a highly promising method for the isolation and preconcentration of trace elements from beverages. By utilizing nonionic surfactants to form micellar structures that encapsulate analytes, CPE significantly enhances extraction efficiency and detection limits, often achieving improvements by several orders of magnitude. The optimization of CPE conditions, particularly the selection of surfactants and complexing agents, plays a crucial role in ensuring accurate analytical results. This review underscores the integration of CPE with spectrometric methods as a powerful approach for the separation, preconcentration, and quantification of numerous (ultra)trace elements across a wide range of beverages, including drinking water, wine, beer, juices, tea, and milk. The analytical potential of this integration is substantiated by the comprehensive examples listed in this paper, which include various strategies for sample preparation tailored specifically for different beverage types. While highlighting the effectiveness of conventional CPE methods, this review also emphasizes recent modifications and advancements in CPE techniques that further enhance their utility in beverage analysis. These advancements not only improve detection sensitivity but also align with the principles of green chemistry by reducing solvent consumption and energy requirements. Full article

Traditional leaf chlorophyll estimation using Soil Plant Analysis Development (SPAD) devices and spectrophotometers is a high-cost mechanism in agriculture. Recently, research on chlorophyll estimation using leaf camera images and machine learning has been seen. However, these techniques use self-defined image color combinations where the system performance varies, and the potential utility has not been well explored. This paper proposes a new method that combines an improved contact imaging technique, the images’ original color parameters, and a 1-D Convolutional Neural Network (CNN) specifically for tea leaves’ chlorophyll estimation. This method utilizes a smartphone and flashlight to capture tea leaf contact images at multiple locations on the front and backside of the leaves. It extracts 12 different original color features, such as the mean of RGB, the standard deviation of RGB and HSV, kurtosis, skewness, and variance from images for 1-D CNN input. We captured 15,000 contact images of tea leaves, collected from different tea gardens across Assam, India to create a dataset. SPAD chlorophyll measurements of the leaves are included as true values. Other models based on Linear Regression (LR), Artificial Neural Networks (ANN), Support Vector Regression (SVR), and K-Nearest Neighbor (KNN) were also trained, evaluated, and tested. The 1-D CNN outperformed them with a Mean Absolute Error (MAE) of 2.96, Mean Square Error (MSE) of 15.4, Root Mean Square Error (RMSE) of 3.92, and Coefficient of Regression (R2) of 0.82. These results show that the method is a digital replication of the traditional method, while also being non-destructive, affordable, less prone to performance variations, and simple to utilize for sustainable agriculture. Full article

Plant-specific TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR (TCP) proteins play critical roles in plant development and stress responses; however, their functions in chrysanthemum (Chrysanthemum morifolium) have not been well-studied. In this study, we isolated and characterized the chrysanthemum TCP transcription factor family gene CmTCP13, a homolog of AtTCP13. This gene encoded a protein harboring a conserved basic helix–loop–helix motif, and its expression was induced by salinity stress in chrysanthemum plants. Subcellular localization experiments showed that CmTCP13 localized in the nucleus. Sequence analysis revealed the presence of multiple stress- and hormone-responsive cis-elements in the promoter region of CmTCP13. The heterologous expression of CmTCP13 in Arabidopsis plants enhanced their tolerance to salinity stress. Under salinity stress, CmTCP13 transgenic plants exhibited enhanced germination, root length, seedling growth, and chlorophyll content and reduced relative electrical conductivity compared with those exhibited by wild-type (WT) plants. Moreover, the expression levels of stress-related genes, including AtSOS3, AtP5CS2, AtRD22, AtRD29A, and AtDREB2A, were upregulated in CmTCP13 transgenic plants than in WT plants under salt stress. Taken together, our results demonstrate that CmTCP13 is a critical regulator of salt stress tolerance in plants. Full article