Papers by Keyword: Green Tea

Abstract: Catechins, naturally derived from green tea leaves, are potent antioxidants known for their anti-inflammatory, antimicrobial, anticancer, cardiovascular, and antidiabetic properties. In this study, green tea catechin was successfully encapsulated within a zeolitic imidazolate framework-8 (cate@ZIF-8) and further incorporated into a calcium alginate hydrogel to improve its stability and bioavailability. The system's encapsulation efficiency, structural properties, and release behavior were comprehensively analyzed. X-ray diffraction (XRD) confirmed that the crystalline structure of ZIF-8 remained intact after catechin encapsulation, while Fourier transform infrared spectroscopy (FT-IR) indicated specific interactions between catechin molecules and the ZIF-8 framework. Scanning electron microscopy (SEM) was employed to examine the morphology of the cate@ZIF-8 particles within the alginate hydrogel matrix. Catechin release studies under different pH conditions demonstrated a controlled release profile, especially in acidic environments. These findings underscore the potential of alginate-embedded cate@ZIF-8 hydrogels as an effective platform for sustained catechin delivery in therapeutic applications.

Abstract: “Mild” oral care products are needed by some groups of people, such as radiotherapy patients. This study developed oral cleansing products containing green tea (Camelia sinensis (L.) Kuntze) extracts with antibacterial activities and Centella asiatica (L.) Urb. extracts with a wound healing activity. We found that 3.13 mg/ml of green tea extract inhibited both Streptococcus mutans and Candida albicans, which can cause dental caries and oral candidiasis, respectively. Also, a 16 μg/ml C. asiatica extract promoted fibroblast migration in a wound healing study. The products were developed in 2 dosage forms, i.e. a solution and an impregnated gauze, which were isotonic, alcohol and volatile oil free formulations to prevent irritation and burning sensations. The products showed acceptable physical stability after testing under stressed conditions with post-test retention of antimicrobial activity.

Abstract: In order to identify the green tea quickly and accurately, the infrared spectra of teas measured by Fourier transform infrared spectroscopy are analyzed by using informatics method of feature extraction in this work. By comparing the different characteristic bases found by different feature genes of different tea samples, it is concluded that when green tea, yellow tea and white tea are chosen to constitute the standardized spectrum data matrix, and its first and third feature gene are selected to build characteristic basis, the green tea can be visually distinguished and the same samples have a very good aggregation. While when the characteristic basis is built by the first and second feature gene or the second and third feature gene, or the samples which are used to make up of standardized spectrum data matrix are all green tea, the recognition effect of green tea is bad. A linear arbiter of green tea is set up according to neutrality line principle on the above effectively characteristic basis, when all samples are projected onto the characteristic basis it is shown that all the green tea fall on the right of arbiter, and all not green teas are on the left of arbiter, consequently, the green tea can be identified.

Abstract: This research aims at examining how to decrease the absolute amount of cement so as to reduce CO2 generated in theprocess of cement production. Accordingly, this research examines the production of mortar by using a non-cement-type ofinorganic powders through industrial by-products such as blast-furnace slag and fly ash, investigates the pH-reducing effect ofcement products by using green tea, and checks the possibility to reduce pH.Inorganic powders were used for mixture of mortar, and experiments were conducted to measure the mortar’s compressivestrength, reduced amount of CO2, and pH concentration. From the test, first, it was found that the compressive strength was similar to the level of OPC when asmall amount of cement was added to inorganic powders, so in terms of compressive strength, the mortar with inorganicpowders was considered to be a good substitute for cement. Second, with regard to the reduction of CO2, CO2 emission was 20to 35 percent of that of cement when inorganic powders were used, which showed they would help greatly alleviate theenvironmental burden on the cement industry. Third, the older the material age was, the lower the pH concentration became,and the pH concentration got lower when GT was added to each type. In addition, mortar with inorganic powders is expected to be an environmentally friendlysubstitute for cement in that its compressive strength was similar to OPC’s and it can reduce emission of CO2.

Abstract: A micellar electrokinetic electrophoresis-laser induced fluorescence detection (MEKC-LIF) method was applied for the profiling of native fluorescence in three different kinds of Chinese green teas. The running buffer was 100 mM sodium borate (pH9.8) containing 20 mM SDS, and tea infusion was injected at the pressure of 0.5 psi for 5 seconds. The applied voltage was set at 25 kV, and the excited wavelength was 488 nm, and the detected wavelength was 520 nm. Ten tea samples were collected and analyzed by the developed method. Eighteen common peaks in the MEKC-LIF profiling of green teas were selected and these samples were classified into 3 groups by cluster analysis and partial least square discriminant analysis (PLS-DA). Our primary results indicated that the developed method could be applied for the classification of three different Chinese green teas

Abstract: The thermal diffusivity of green teas has been used as engineering parameter in the design of processes and machines for drying, storing and aeration. The thermal diffusivity of green teas was determined and its changes with moisture content, bulk density investigated. The thermal diffusivity values of green teas decreased from 8.126×10^-8 at 250 kgm^-3 to 5.037×10^-8 m²s^–1 at 550 kgm^-3. The change of the thermal diffusivity of green teas at different moisture content shows that it increased from 8.281×10^-8 at 5.3% db to 12.617×10^-8 m²s^–1 at 70.0% db and from 7.497×10^-8 at 5.3% db to 12.464×10^-8 m²s^–1 at 70.0% db, respectively, as bulk density increased.

Abstract: Objective: To study the processing technology and formula of peanut–tea beverage, and further provide reference for the plant protein beverage. Methods: The peanut was baked in the far-infrared oven, soaked with soft water containing 5% NaHCO₃, rinsed and then cooked for 30 min, milled at 0.05 mm spacing grinding, filtered and finished peanut slurry. Tea leaves were extracted twice by water of 90°C. The two ingredients were combined with other supplement, refined by colloid mill, homogenized twice, followed by bottling, sealed, sterilization, cooled and other processing. In this study, the formula, stabilizers and additives by orthogonal experiments were investigated. Results: The peanut slurry and sugar were found to be major factors which affected the beverage’s quality. The formula was optimized when the content of peanut slurry, tea and sucrose reached 75 mL, 25 mL and 4 g especially in per 100 mL peanut-tea beverage. As single stabilizer, CMC-Na showed the most significant effect, and storage temperature was found to be better at room temperature than low temperature. Compared with single stabilizer, compound stabilizer was better. The optimal formula was CMC-Na 0.4 g/L, seaweed sodium 0.2 g/L, gelatin 0.8 g/L. Conclusion: The peanut-tea beverage, with unique flavor and rich nutrients, was a novel type of health plant beverage which was suitable for a large variety of people, and had a promising market.

Abstract: Epigallocatechin gallate (EGCG), a major polyphenol of green tea, has been shown to inhibit the growth of various cancer cell lines. Co²⁺ is one of essential trace elements of human nutrition, both lack and excess have adverse effects on health.In this research, MTT assays were applied to investigate the effects of Co²⁺, EGCG and their coactions on Cal-27 cells, The results show that Co²⁺ and EGCG inhibited the growth of Cal-27 cells in a time-and dose-dependent model, and inhibition effects were extremely dependent on their concentrations, added orders and [Co²⁺]/[EGCG] ratio. Inhibitory effects of Co²⁺ could be decreased in the presence of EGCG. LC/MS analysis showed that a new component arised when EGCG and Co²⁺ were mixed together. It was inferred that the new components were [EGCG-2Co] and [EGCG-Co], and the process might be responsible for the observed effect of the bioactivities of Co²⁺ against Cal-27 cells.

Abstract: Green tea dyeing of cotton fabric via azoic combination method was investigated in order to improve ultraviolet protection properties without the application of polutting metal mordants. Three types of diazonium salts were prepared from three different primary aromatic amines (aniline, p-nitroaniline and 2,4 dichoroaniline) and subsequently, reacted with pretreated cotton fabric with coupling component or polyphenolic compounds found in green tea extract to form an azo dye inside the cellulose matrix. The result showed that as the strength of electron withdrawing groups of the substituents in the primary aromatic amines increase, both color strength and ultraviolet protection factor (UPF) of dyed fabrics dramically increased.

Abstract: This study discussed the feasibility of taste quality evaluation for green tea infusion using electronic tongue. Chemistry evaluation was regarded as the reference measurement, and used to measure total taste scores of green tea infusion. LS-SVM was used to build the correlativity between the sensor signals of green tea infusion and total taste scores by the reference measurement, and compared the influence of different principal components on the performance of LS-SVM model. Experimental results showed that the optimal model was obtained when 4 PCs were included with Rc=0.951 and RMSECV=3.242 in calibration set, Rp=0.904 and RMSEP=4.134 in the prediction set. This study showed that the electronic tongue had a great potential in the evaluation of taste quality for green tea and LS-SVM was an efficient method to build the evaluation model based on electronic tongue.