This review focuses on the research progress related to carbon dots (CDs) derived from Chinese herbal medicines and tea, covering preparation methods, physicochemical properties, and application fields. It elaborates on preparation approaches like hydrothermal, solvothermal, microwave-assisted, and ultrasonic-assisted methods, and their influence on CDs’ structure and properties. It also explores CDs’ structural and optical properties. The application fields include antibacterial, sensing, bioimaging, photocatalysis, hemostasis, and energy. Carbon dots show antibacterial activity by destroying bacterial cell membranes, they can detect various substances in sensing, are important for bioimaging, degrade organic pollutants in photocatalysis, have hemostatic and anti-inflammatory effects, and can be used as battery anode materials. Despite progress, challenges remain in improving yield, quantum yield, property control, and understanding their mechanism of action. This review provides a reference for related research and looks ahead to future directions.

Graphite-carbon nitride (g-C₃N₄) was prepared by thermocondensation, and g-C₃N₄/BiVO₄ material (GCB) and g-C₃N₄/CNTs composite material (GCC) were prepared by doping different contents of BiVO₄ and carbon nanotubes (CNTs) with g-C₃N₄ samples, respectively. Then, BiVO₄, CNTs, and g-C₃N₄ samples with different contents were doped to prepare ternary composite material (GCBC). In the performance experiment, Sulfamethoxazole (SMZ) was used as degradation material to evaluate the photocatalytic performance of the prepared samples, and the degradation reaction kinetics equation, quadric cycle stability experiment, free radical capture, and intermediates identification were studied. The intermediates of photocatalytic degradation of SMZ were analyzed by high-performance liquid chromatography-mass spectrometry. From the experimental data, it can be seen that for SMZ solution, when the reaction time T = 0 min and retention time rt = 7.53 min, there is a peak corresponding to the substance with m/z [M + H]⁺ of 254, which is judged as SMZ. At 20, 40, and 60 min, rt was 2.00, 7.06, and 9.57 min, indicating the presence of intermediates in the photocatalytic process. Experimental analysis shows that there are three intermediates of SMZ degradation by composite sample GCBC. In this work, three kinds of composite materials were successfully prepared, and a variety of characterization, SMZ as pollutants, test the photocatalytic performance of composite materials (GCB, GCC, and GCBC) samples, and elucidated the cyclic stability of the material, active species capture, and photocatalytic degradation mechanism.

This study established a chromatographic fingerprint analysis method for aged rock tea using ultra‐high performance liquid chromatography–mass spectrometry (UPLC–MS) technology to profile its chemical components. The chromatographic separation showed excellent performance, with more than 30 chemical components of common peaks identified. Comparative analysis of fingerprint profiles from different vintage‐aged teas revealed significant differences in similarity, allowing classification into three distinct categories based on similarity indices. This method facilitates the classification of aged teas and quality evaluation of traditional Chinese medicinal materials. Component analysis of aged tea demonstrated that tea extracts are rich in flavonoid compounds, both in content and diversity, serving as a primary dietary source of total flavonoids. In subsequent animal experiments, functional flavonoids derived from aged tea extracts exhibited positive regulatory effects against multiple free radicals, including ·OH, H ₂ O ₂ , DPPH ⁻ , and ABTS, in vitro. In vivo studies showed that these flavonoids reduced malondialdehyde (MDA) levels in the cerebral cortex of Alzheimer’s disease (AD) mice, enhanced the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), mitigated oxidative damage, and improved cognitive dysfunction in AD mice. This research provides crucial references for future studies on traditional Chinese medicines aimed at ameliorating cognitive dysfunction.

In this study, a comparative analysis of the extraction yields of flavonoids, polyphenols, and terpenes from aged Wuyi rock tea of different years in solvents such as petroleum ether, dichloromethane, ethyl acetate, n-butanol, and water was conducted, which provides a theoretical basis for the separation and purification of active components. A 75% ethanol reflux extraction method was employed to prepare the ethanol extract, followed by extraction of the aqueous suspension using different polar organic solvents and deep eutectic solvents. The contents were determined by UV spectrophotometry. The results showed that the total extraction yields of flavonoids and polyphenols varied with the solvents, in the order of n-butanol, ethyl acetate, water, dichloromethane, and petroleum ether; for triterpenoids, the order was n-butanol, water, petroleum ether, ethyl acetate, and dichloromethane. N-butanol was identified as the optimal solvent. This study also detected a flavonoid compound, presumably glycyrrhizic acid, based on comparisons with existing literature and information. Currently, research and development on flavonoids, polyphenols, and triterpenoids in aged tea are underway, aiming to further explore the value and application potential of tea and contribute to the development of the tea industry.