Camellia Sinensis Research Articles (Page 1)

The aim of the study was to develop a salami-type meat sausage enriched with the probiotic bacteria Lacticaseibacillus paracasei and a mixed plant extract containing rosemary (Rosmarinus officinalis L.) and green tea (Camellia sinensis) and to evaluate its physicochemical and microbiological characteristics. In the study, salami-type meat sausages were developed and divided into 11 equal portions, which were added with different concentrations of mixed extract (1–3.4%) and probiotic (1.5–3.5%), totaling 11 formulations according to a Central Composite Rotating Design. Lipid oxidation, instrumental color, pH, aw, and microbiological analyses (count of lactic acid bacteria, thermotolerant coliforms, coagulase-positive staphylococci, and Salmonella) were performed to evaluate the developed products. There was a significant effect of varying the mixed extract and probiotic concentration on the lipid oxidation, color parameters, and lactic acid bacteria count responses. Lower lipid oxidation values were observed in the combination of lower concentrations of mixed extract (0.5–1.5%) with intermediate concentrations of the probiotic (2.25–2.75%). All formulations contained lactic acid bacteria above 8 Log10 CFU/g throughout the shelf life. It was concluded that the addition of L. paracasei to salami-type sausage is viable and, in combination with the mixed extract of rosemary and green tea, can inhibit lipid oxidation.

Tea is one of the most widely consumed beverages worldwide, yet increasing environmental cadmium (Cd2+) contamination poses a serious threat to consumer safety. Understanding the migration pathway of Cd2+ from contaminated soils through tea plants into brewed infusions is essential for comprehensive risk assessment across the entire tea supply chain. However, conventional analytical methods for Cd2+ detection are often time-consuming, labor-intensive, and unsuitable for rapid or on-site monitoring. In this study, we developed a facile, sensitive, and selective electrochemical sensing platform based on a Bi3+-rich metal–organic framework (MOF(Bi)) for reliable Cd2+ quantification in various tea-related matrices. The MOF(Bi) was synthesized via a solvothermal method and directly immobilized onto a glassy carbon electrode (GCE) in a one-step modification process. To enhance Cd2+ preconcentration, cysteine was introduced as a complexing agent, while Nafion was employed to stabilize the sensing interface and improve reproducibility. The resulting Nafion/cys/MOF(Bi)/GCE sensor exhibited excellent sensitivity with a wide linear range from 0.2 and 25 μg/L, a low detection limit of 0.18 μg/L (S/N = 3), high selectivity against common interfering ions, and good stability. This platform enabled accurate tracking of Cd2+ transfer from polluted garden soil to raw tea leaves and finally into tea infusions, showing strong correlation with ICP-MS results. Our strategy not only offers a practical tool for on-site food safety monitoring but also provides new insights into heavy metal transfer behavior during tea production and consumption.

d-limonene is a key monoterpene that contributes to the characteristic aroma of tea (Camellia sinensis) and plays a defensive role against pathogenic infections. However, the regulatory mechanisms underlying its biosynthesis and associated disease resistance remain largely elusive. In this study, d-limonene levels were found to be significantly elevated in pathogen-infected tea leaves, and exogenous application of d-limonene markedly enhanced resistance to gray blight disease. Transcriptomic analysis identified CsTPS5, encoding a terpene synthase, as bening strongly induced upon pathogen challenge. Subcellular localization, in vitro enzyme assays, and in vivo functional verification demonstrated that CsTPS5 catalyzes the conversion of geranyl diphosphate (GPP) into d-limonene. Furthermore, yeast one-hybrid screening, electrophoretic mobility shift assays (EMSA), and dual-luciferase reporter assays revealed that the bHLH transcription factor CsbHLH124 directly binds to the promoter of CsTPS5 and activates its expression. Gene silencing experiments further confirmed that the CsbHLH124-CsTPS5 regulatory module plays a crucial role in promoting d-limonene biosynthesis and suppressing lesion formation caused by Pseudopestalotiopsis camelliae-sinensis (Ps.cs.). These findings elucidate a previously uncharacterized regulatory pathway controlling terpene metabolism and provide a promising molecular framework for enhancing both aroma quality and disease resistance in tea breeding programmes.

Summary statement Toxoptera aurantii honeydew enhances Ectropis obliqua fitness by reducing defensive catechins in leaves of Camellia sinensis via JA‐independent manner. Honeydew‐derived trehalose reduces defensive catechins in leaves while boosting leaf water content, promoting larval growth of E. obliqua .

Tea (Camellia sinensis (L.)O. Kuntze) converts inorganic selenium into organic selenium, including selenomethionine (SeMet). Drying improves tea flavor, but the thermal mechanism by which drying time affects flavor compounds and proteins in selenium-enriched black tea remains unclear. 98 different flavor components and 87 proteins were identified by metabolomics and proteomics at 12-54 min of hot-air drying (70 °C, 7.0-0.1% moisture). Amino acid biosynthesis and glutathione metabolic pathways were significantly affected under heat. Key flavor compounds (SeMet, cysteine, serine, etc.) and proteins (methionine synthase, etc.) were maintained at high abundance. SeMet peaked at 36 min (1.23 mg kg-1), which increased by 19.4, 17.1, 16.0, and 61.8% compared with 12, 24, 48, and 54 min (1.03, 1.05, 1.06, and 0.76 mg kg-1, respectively). Optimal drying (70 °C for 36 min; 3.0% moisture) minimized thermal degradation losses of flavor components like SeMet, providing a theoretical basis for maintaining the high-quality of tea.

Over-expression of CsHAK4 from tea plant (Camellia sinensis L.) negatively regulates high salt tolerance in transgenic Arabidopsis.

Natural guanidine alkaloids in tea (Camellia sinensis): Identification, quantification and α-glucosidase inhibitory activity of cis- and trans-cinnamoylagmatines.

The function and application potential of L-theanine: From biotechnological production, biosynthesis, bioactivity to food industry.

Valorization of tea (Camellia sinensis) waste: Extraction of bioactive compounds using ionic liquids and evaluation of their stability, efficiency, and volatile profiles during the process.

Tea (Camellia sinensis) is prized for its polyphenols, which dictate flavor and confer health benefits, yet its inherent caffeine content poses health risks to vulnerable populations. Therefore, developing methods for producing decaffeinated tea extract is important. This study aims to synthesize mordenite zeolite from kaolin and evaluate its potential application for selective caffeine adsorption in the production of decaffeinated tea beverage. Characterization via x-ray diffraction (XRD) confirmed the formation of a crystalline mordenite structure. Brunauer-Emmett-Teller (BET) analysis demonstrated a specific surface area of 77.9989m2/g, though residual kaolinite and mica impurities limited the micropore volume to 0.084875cc/g. We investigated the caffeine adsorption behavior in simulated and green tea extract solutions. In simulated caffeine solutions (400-2000mg/L), optimal adsorption was achieved at pH 2, yielding a removal efficiency of 90.69% and an adsorption capacity of 14.5mg/g. However, pH 3 was used for adsorption in the green tea extract, resulting in 85.84% caffeine removal while retaining 78.15% of total polyphenols. The adsorption kinetics of caffeine in both systems were well represented by the pseudo-first-order with R2>0.99. PRACTICAL APPLICATIONS: Mordenite zeolite (MOR zeolite) can selectively remove caffeine from green tea extract, creating decaffeinated tea solutionwhile preserving most of its beneficial polyphenols. This process could be applied to industrial manufacturing of green tea extract that is low in caffeine, which is suitable for health-conscious consumers, pregnant women, children, and elderly individuals who want the health benefits of tea without caffeine's side effect.

Multi-omics profiling reveals the dynamic interplay between processing-induced phytochemical transformation and antioxidant bioactivity in 'Huangkui' tea (Camellia sinensis).

Effects of fermentation of Eurotium cristatum on the flavor quality of Anji Baicha (Camellia sinensis) based on LC-MS and GC-MS.

CsWRKY57L enhances freezing tolerance through flavonoid accumulation and modulates growth via SWEETs in tea plants

Selenium-enriched tea - chemical composition and health benefits.

Potential of tea seeds as new functional raw materials: Comprehensive analysis of main nutrient substances and active components.

Pyrrolizidine alkaloid contamination in loose tea and its health risk assessment.

Experimental study of thermochemical behavior and pyrolysis kinetics of tea plant residues via TG-FTIR

Transmission of microorganisms that cause disease in humans occurs directly or indirectly. Prevention efforts can use antiseptics. The content of liquid smoke compounds in tea twigs has the potential to be an antiseptic. The purpose of this study was to determine the effectiveness of liquid smoke from tea twigs (Camellia sinensis) on microbial growth in vitro using the inhibition test method and in vivo swab test on the palms. In the in vitro test, the most effective results were grade 2 liquid smoke with a concentration of 75% with an inhibition zone diameter of 18.1 mm (E. coli ATCC 25922), 15.6 mm (S. aureus ATCC 25923), 32.3 mm (A. flavus ATCC 9643), 4.3 mm (C. albicans ATCC 10231). The results of the in vivo test showed effectiveness in reducing the number of bacterial colonies by an average of 88.33%, and fungal colonies by an average of 91.52%. From the entire questionnaire data, the parameters of aroma, color, dryness are in the criteria of liking and do not cause side effects on the skin. The results of the study showed that liquid smoke from tea twigs has the potential as an antiseptic.

Lead Acetate and Biosynthesized Pb-NPs Induced Histopathology in Nile Tilapia: Mitigation by Camellia Sinensis and Vitamin E

Fairy chemicals (FCs), such as 2-azahypoxanthine (AHX), 2-aza-8-oxohypoxanthine (AOH), and imidazole-4-carboxamide, are molecules with diverse functions in plants. Methylation of plant hormones is recognized to affect the physiological functions of plants. We predicted that plants regulate the physiological activity of FCs through methylation and launched a project searching for methyl derivatives of FCs. We synthesized 7-methyl-AHX (1), 9-methyl-AHX (2), 7- methyl-AOH (3), 9-methyl-AOH (4), and 1,7,9-trimethyl-AOH (5). 1-Methyl-AOH (6) and 1,9-dimethyl-AOH (7) were isolated from AOH-treated tea cells. By using these purines as authentic compounds to analyze tea plant and coffee plant, we found that 1, 2, and 4-7 are endogenously produced in tea plant and 5 in coffee plant. Furthermore, quantitative analysis revealed that 5 was accumulated in the highest amounts. Furthermore, 2 showed growth-promoting activity and 5-7 showed growth-inhibiting activity on tea cells. These results suggest that tea plants might methylate FCs to modulate their physiological activity.