Search Results (41)

Metabolic dysfunction-associated fatty liver disease (MASLD) is a chronic, non-communicable spectrum of diseases characterized by lipid accumulation. It is often asymptomatic, and its prevalence varies by region, age, gender, and economic status. It is estimated that 25% of the world’s population currently suffer from MAFLD, and 20 million patients will die from MAFLD-related diseases. In the last 20 years, tea and anti-obesity research have indicated that regularly consuming tea decreases the risk of cardiovascular disease, stroke, obesity, diabetes, and metabolic syndrome (MeS). In this review, we aimed to present studies concerning the influence of matcha extracts and epigallocatechin-3 gallate (EGCG) supplements on metabolic functions in the context of MAFLD in human and animal studies. The published data show promise. In both human and animal studies, the beneficial effects on body weight, cholesterol levels, and liver metabolism and function were noted, even in short-period experiments. The safety levels for EGCG and green tea extract consumption are marked. More experiments are needed to confirm the results observed in animal studies and to show the mechanisms by which green tea exerts its effects. The preliminary data from research concerning microbiota or epigenetic changes observed after polyphenols and green tea consumption need to be expanded. To improve the efficiency and availability of green tea or supplement consumption as a treatment for MAFLD patients, more research with larger groups and longer study durations is needed. Full article

Background/Objectives: Mood disorders include symptoms of depression, anxiety, and or stress, and have increased in prevalence. Green tea and its bioactive components (epigallocatechin gallate [EGCG] and L-theanine) have been investigated for their health benefits and neuroprotective properties. As adults seek integrative and alternative treatment modalities, it is relevant to determine the effects of natural and non-pharmacological treatments on humans. This study aimed to assess current evidence from published randomized controlled trials testing the effects of green tea, green tea extracts, or its bioactive compounds on mood disorder symptomology and brain-derived neurotrophic factor (BDNF). Methods: We searched PubMed, Cochrane Library, PsycINFO, Embase, Google Scholar, and ClinicalTrials.gov, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist and utilizing predetermined inclusion and exclusion criteria. Results: A total of 445 studies were identified, 395 screened, and thirteen met inclusion criteria. Seven used one of the bioactive compounds found in green tea for intervention, while six used green tea extract, matcha, or traditional green tea. Mood disturbance was assessed with several tools, with studies reporting improvements in depressive (n = 4), anxiety (n = 6), stress (n = 5), and sleep (n = 1) symptoms. No studies found a statistically significant effect of green tea or its bioactive compounds on BDNF. Conclusions: Our findings suggest green tea, GTE, L-theanine, and EGCG may improve mood disorder symptomology, particularly symptoms of depression; no evidence to date reports effects on BDNF. Full article

Matcha, a finely powdered green tea, has been cherished in Japan for centuries, used in the traditional tea ceremony and nowadays also valued for its health-promoting properties. Cultivated under shaded conditions to enhance chlorophyll production, which gives the typical vibrant green color, matcha is rich in important bioactive compounds, including caffeine, catechins, and theanine. This study analyzes three matcha grades—ceremonial grade 1 (G1), grade 4 (G4), and food grade (FG)—to assess variations in their metabolite profiles. The Bligh–Dyer method was employed to extract polar and non-polar metabolites from organic and hydroalcoholic phases. High-performance thin-layer chromatography (HPTLC) was used for qualitative metabolite analysis, while nuclear magnetic resonance (NMR) spectroscopy was employed for both qualitative and quantitative analyses. Results reveal a decreasing gradient of amino acids and caffeine from grade 1 to food grade, while other metabolites, such as polyphenols, display an increasing trend. These findings suggest that factors such as harvesting time and leaf maturity significantly influence matcha’s chemical composition, providing a scientific basis for its quality differentiation and potential nutraceutical uses. Full article

This study explores the potential of some commercially available plant proteins to increase the protein content of gluten free cookies produced from green lentil flour. Isolates from hemp seed, brown rice, yellow pea, and pumpkin seed were investigated. Cookies were additionally enriched with inulin and matcha tea. Products were characterized in terms of physicochemical parameters (e.g., crude protein content, total phenolics and flavonoids, antioxidant activity, and color). Additionally, technological properties including geometry, baking loss, and texture profile were determined, and a sensory profile test was conducted. The replacement of a quarter of lentil flour with plant proteins increased the protein content (control: 12.4% vs. 15.1–20.4%), but suppressed the polyphenol content, resulting in reduced antioxidant capacity (3.13 vs. 2.14–2.69 mmol TE/100 g). The geometry, texture properties, and color of the cookies were affected by all the proteins investigated. The biggest difference was shown in the case of using yellow pea (YP) protein, which showed the highest browning index (YP: 66.36 vs. 42.63–63.45) and spread ratio (8.38 vs. 5.63–6.39) among the samples tested. The sensory attributes of the cookies, such as tea notes, surface homogeneity, crunchiness, and crumbliness, proved to be negatively affected by the plant proteins, which may be a limitation for consumer acceptance. Full article

Matcha is reported to have high content of some bioactive components such as catechins, theanine, and caffeine, and its consumption is increasing worldwide. Several analytical methods have been established for matcha powder and bioactive compounds, but most of them are based on HPLC methods. This study focused on NMR as an analytical method for simple quantitative analysis of the functional components of matcha. The analytical conditions were established by preparing extract and solvent fractions, evaluating hygroscopicity, and examining quantitative NMR parameters. The analytical performance was evaluated, and the developed analytical condition was also applied to matcha powder by directly mixing in NMR solvent without pre-extraction. Caffeine, epicatechin, epicatechin-3-O-gallate, epigallocatechin-3-O-gallate, epigallocatechin, gallocatechin-3-O-gallate, and gallocatechin were quantified. Analysis of matcha and normal green tea powder suggested the possibility of distinguishing between matcha and green tea powder by the ratio of caffeine content and total catechins content. The qNMR method can be adopted for the simple analysis of the amount of caffeine and catechin compounds in the powders and extracts. Full article

Matcha is a very popular tea food around the world, being widely used in the food, beverage, health food, and cosmetic industries, among others. At present, matcha shade covering methods, matcha superfine powder processing technology, and digital evaluations of matcha flavor quality are receiving research attention. However, research on the differences in flavor and quality characteristics of matcha from the same tea tree variety from different typical regions in China is relatively weak and urgently required. Taking Japan Shizuoka matcha (R) as a reference, the differences in sensory quality characteristics and non-volatile substances of matcha processed with the same tea variety from different regions in China were analyzed. The samples were China Hangzhou matcha (Z1), China Wuyi matcha (Z2), China Enshi matcha (H), and China Tongren matcha (G), which represent the typical matcha of eastern, central, and western China. A total of 1131 differential metabolites were identified in the matcha samples, comprising 118 flavonoids, 14 tannins, 365 organic acids, 42 phenolic acids, 22 alkaloids, 39 saccharides, 208 amino acids and derivatives, 17 lignans and coumarins, seven quinones, 44 nucleotides and derivatives, 14 glycerophospholipids, two glycolipids, 15 alcohols and amines, 140 benzenes and substituted derivatives, 38 terpenoids, 30 heterocyclic compounds, and 15 lipids. Kaempferol-7-O-rhamnoside, 3,7-Di-O-methylquercetin, epigallocatechin gallate, epicatechin gallate, and epigallocatechin were detected in Z1, Z2, H, and G. A total of 1243 metabolites differed among Z1, Z2, and R. A total of 1617 metabolites differed among G, H, and R. The content of non-volatile difference metabolites of Z2 was higher than that of Z1. The content of non-volatile difference metabolites of G was higher than that of H. The 20 key differential non-volatile metabolites of Z1, Z2, G, and H were screened out separately. The types of non-volatile flavor differential metabolites of G and H were more numerous than those of Z1 and Z2. The metabolic pathways, biosynthesis of secondary metabolites, biosynthesis of co-factors, flavonoid biosynthesis, biosynthesis of amino acids, biosynthesis of various plant secondary metabolites, and purine metabolism of metabolic pathways were the main KEGG pathways. This study provides new insights into the differences in metabolite profiles among typical Chinese matcha geographic regions with the same tea variety. Full article

Background/Objectives: Plant-derived compounds are increasingly valued in drug discovery for their therapeutic potential. This study aims to examine the antimicrobial, antioxidant, and anticancer properties of kombucha beverages fermented with Gardenia jasminoides (GJ) and various types of Camellia sinensis teas: matcha green tea (MGT), organic green tea (OGT), and decaffeinated green tea (DGT). Methods: Two experimental designs were employed: (1) using black tea as a base substrate, infusing the four teas post-fermentation over 0–14 days, and (2) directly fermenting tea–herb combinations over 0–21 days. Antioxidant activity was assessed via the DPPH assay. Microbial dynamics were analyzed through total mesophilic bacteria and Lactobacillus counts. Antimicrobial potential was evaluated against E. coli, S. aureus, and S. enteritidis over 24 h. Cytotoxicity assays were conducted on Caco-2 and U251 cell lines to assess anticancer effects, with pH-adjusted controls used to differentiate bioactivity from acidity. Results: In the first experiment, GJ kombucha displayed the highest antioxidant potential (IC50: 14.04 µg/mL), followed by MGT (IC₅₀: 32.85 µg/mL) and OGT (IC₅₀: 98.21 µg/mL). In the second setup, unfermented GJ kombucha initially showed high antioxidant activity (IC₅₀: 12.94 µg/mL), improving during fermentation to reach an IC₅₀ of 18.26 µg/mL by day 21. Microbial analysis indicated moderate increases in total mesophilic bacteria and Lactobacillus in GJ kombucha after 14 days, while MGT, OGT, and DGT exhibited higher increments. GJ kombucha consistently demonstrated the highest antimicrobial activity against E. coli, S. aureus, and S. enteritidis, with significant inhibitory effects observed by 24 h. Cytotoxicity assays showed that GJ kombucha reduced Caco-2 cell viability to 20% at 800 µg/mL after 14 days, while U251 cells maintained 50% viability at the same concentration. Conclusions: This study highlights the antimicrobial, antioxidant, and anticancer potential of GJ kombucha, with fermentation enhancing bioactive metabolite production. Optimizing fermentation conditions, identifying specific bioactive compounds, expanding cytotoxicity testing, and exploring broader therapeutic applications of kombucha could maximize its health benefits and establish it as a natural antimicrobial and anticancer agent. Full article

Background/Objectives: This study tested the influence of in vitro digestion on the release of organic acids and low molecular weight saccharides of matcha. Methods: The concentrations of analytes in the raw and undigested portion of matcha were measured using HPLC with spectrometric and refractometric detection to establish their residual values after a two-step enzymatic digestion that was finally presented as a retention factor. Results: It was established that dry matter digestibility values after simulated gastric and both gastric and intestinal phases were 67.3 and 85.9%, respectively. Native matcha, citric acid (44.8 mg/g), malic acid (32.2 mg/g), trehalose (36.1 mg/g), and L-arabinose (8.20 mg/g) reached the highest values and were predominant, whereas D-fructose, xylose, maltose, and saccharose were not detected. Regarding gastric phase digestion, succinic and malic acids, trehalose and D-glucose were the worst-releasing compounds and their remaining factors reached 34, 19, 18, and 50%, respectively, whereas L-arabinose was completely released. Focusing on gastric and small intestinal digestion, the least-releasing compounds of matcha tea leaves were succinic acid and trehalose, with their retention factors at 7 and 13%, which can proceed with the leaf matrix to the large intestine. Conclusions: Malic, oxalic, and citric acids, the carbohydrates D-glucose, L-arabinose, and L-rhamnose, are almost entirely released from matcha tea during digestion in the stomach and small intestine and can be available for absorption in the small intestine. In the measurement of oxalic acid, considering that the process of shading tea leaves increases the concentration of this acid and its retention factor value is too small, it would be appropriate in the future to evaluate the recommended maximum daily intake of matcha tea for people sensitive to the formation of urinal stones. Full article

Color is a key indicator for evaluating the quality of tea during processing; various processing procedures can significantly affect the content of fat-soluble pigments of tea, which in turn affects the color and quality of finished tea. Therefore, there is an urgent demand for the fast, non-destructive detection of pigments of stacked tea during processing. This paper presents the use of hyperspectral imaging technology (HSI), combined with machine learning algorithms, to detect chlorophyll a, chlorophyll b, and carotenoids in stacked matcha tea during processing. Firstly, a quantitative relationship between HSI data of tea and their pigment contents was developed based on regression analysis, and the results showed that exceptional prediction performance was achieved by the partial least squares regression (PLSR) algorithm combined with the feature band algorithm of competitive adaptive reweighting (CARS), and the R_p² values of detection models of chlorophyll a, chlorophyll b and carotenoids were 0.90465, 0.92068 and 0.62666, respectively. Then, these quantitative detection models were extended to each pixel in hyperspectral images, achieving point-by-point prediction of pigment components, so the distribution of pigments of stacked tea leaves during processing procedures was successfully visualized on the processing line in situ. By integrating a hyperspectral imaging system into the real-world environment, operators can monitor pigment levels in real time and thus dynamically adjust processing parameters based on real-time data. This study enhances pigment detection efficiency in tea processing, supports process optimization, and aids in quality control. Full article

In the present study, the processing, characterization, and assessment of novel non-alcoholic and sugar-free drinks based on bioactive extracts from valuable natural sources, such as green tea enriched with Chios mastiha, are considered. Currently, the transition towards the consumption of healthy and sustainable food and beverages promoting human health and well-being is strongly encouraged and biologically active compounds from natural resources have a broad range of ap-plications in this sector. In this context, three beverages (all non-alcoholic, non-carbonated, and sugar-free) were created, including extracts of green tea with Chios mastiha, matcha green tea with Chios mastiha and louisa green tea with Chios mastiha, and an evaluation of their biological potential was performed. Specifically, an analysis of water, extracts, and additives for the beverage production was carried out. Microbiological and nutritional value determination was also conducted in samples of the three products. According to the experimental results, the novel health beverage produced from green tea enriched with Chios Mastiha extracts was found to have improved organoleptic characteristics and was microbiologically stable and safe for a period of 180 days from the production date at 25 °C. It is also considered stable and safe for 3 days after production, even if it remains open at 25 °C. In view of a possible scale-up of this application, safety, and preservation control should continue for at least 540 days from the date of production. In conclusion, the current research findings support the development of a novel non-alcoholic sugar-free health drink based on bioactive extracts from green tea enriched with Chios mastiha, to contribute to maintaining human health and also to strengthen the economy. Full article

Theanine, an amino acid unique to tea leaves, has been reported to exhibit stress-relieving effects. However, the stress-relieving effects of theanine (T) are greatly inhibited by caffeine (C) and epigallocatechin gallate (E), the main components of green tea, while being enhanced by arginine (A). Animal and clinical studies using matcha tea have shown that it can alleviate stress if the molar ratio of C and E against T and A (CE/TA) is less than 2. In general, the CE/TA ratio in tea leaves is reflected by the CE/TA ratio in the infused solution; however, it is not clear what infusion conditions would be expected to ensure a stress-relieving effect. In this study, to examine the stress-relieving effect of green-tea-infused solutions, the CE/TA ratio was measured under different infusion conditions. Furthermore, a study using a model solution consisting of C, E, T, and A revealed that a CE/TA ratio of at least less than 2 and a T content greater than 0.23 mM were required for stress reduction. Based on these results, we identified tea leaves and their infusion conditions that can be expected to reduce stress. Full article

Adolescent carriers of the Aggregatibacter actinomycetemcomitans JP2 genotype have an increased risk of developing periodontitis, due to the bacterium’s high leukotoxin (LtxA) production. LtxA contributes to marginal bone loss by killing immunity cells, thus activating the proinflammatory interleukin-1β (IL-1β), which, in turn, activates the osteoclasts. A possible strategy to prevent periodontitis might be to neutralize LtxA in JP2-infected individuals. The aim of this study was to investigate whether extracts from Matcha or Guava leaves can prolong the viability of macrophages in cell cultures by neutralizing the highly leukotoxic JP2 genotype bacteria. The A. actinomycetemcomitans JP2 genotype was pretreated with extracts from either Matcha or Guava leaves. Later, the extracts were rinsed off, before JP2 bacteria were exposed to macrophage cell cultures. The experiment was repeated, where JP2 bacteria were persistently treated with the extracts instead, i.e., the extracts were not rinsed off. The macrophage viability after bacterial exposure was analyzed and compared with that of macrophages exposed to untreated JP2 bacteria. IL-1β secretion in the cell culture medium was quantified in all group samples. Pretreatment of the A. actinomycetemcomitans JP2 genotype with Matcha or Guava leaf extracts moderately neutralized LtxA activity, which resulted in prolonged macrophage viability and decreased IL-1β secretion. These effects of prolonged macrophage viability were enhanced when extracts were persistently present during the exposure period. The results indicate that Matcha and Guava leaf extracts have effects on the virulence of the A. actinomycetemcomitans JP2 genotype that may be useful in future treatment strategies to prevent periodontitis in JP2 bacterium carriers. Full article

Although theanine in matcha improves sleep quality and cognitive function, the caffeine in green tea is thought to worsen sleep quality. Therefore, this study investigated the factors behind the observed improvements in subjective sleep quality in matcha. A placebo-controlled randomized double-blind parallel-group study was conducted on healthy Japanese men and women aged 27–64 years. After 4 weeks of consuming 2.7 g of matcha daily (containing 50.3 mg theanine, 301.4 mg catechins, and 71.5 mg caffeine), no significant differences were observed between the control and matcha groups on total sleep time, sleep latency, wake after sleep onset, or sleep efficiency measured by electroencephalography (EEG). However, the sleep questionnaire Oguri–Shirakawa–Azumi Sleep Inventory, the Middle-age and Aged version (OSA-MA), administered immediately after waking showed a trend toward increased satisfaction with sleep time (p < 0.1), and EEG measurements indicated significantly shortened wake-up times after waking with matcha intake (p < 0.05). The Beck Depression Inventory-II scores also tended to decrease (p < 0.1). The continuous intake of matcha may offer improved subjective sleep quality and emotional stability despite not offering significant changes in objective sleep parameters. Full article

Matcha, or powdered green tea, has been gaining popularity and is no longer consumed only in the form of infusions, finding new uses in gastronomy and the food industry. The range of teas available on the food market has expanded considerably; hence, the aim of this study was to determine, for the first time, the antioxidant capacity and contents of antioxidant compounds in various Matcha teas available on the Polish market, taking into account the country of origin, time of harvest, and conventional vs. organic cultivation. Eleven green-tea powders were used in the analyses performed using spectrophotometric methods (Trolox equivalent antioxidant capacity, Ferric-Ion-Reducing Antioxidant Power, Total Polyphenol Content, Total Flavonoid Content, Vitamin C Content) and HPLC methods (polyphenolic acids, flavonoids, and caffeine). Antioxidant capacity ranged from 7.26 to 9.54 mM Trolox equivalent/L while reducing power ranged from 1845.45 to 2266.12 Fe(II)/L. Total phenolic content amounted to 820.73–1017.83 mg gallic acid equivalent/L, and total flavonoid content was 864.71–1034.40 mg rutin equivalent /L. A high vitamin C content was found, ranging from 38.92 to 70.15 mg/100 mL. Additionally, a high content of caffeine that ranged between 823.23 and 7313.22 mg/L was noted. Moreover, a high content of polyphenolic compounds, including epicatechin gallate, myricetin, gallic acid, and 4—hydroxybenzoic acid, was found. The phytochemical composition and antioxidant properties depended on the harvest time, type of cultivation, and country of origin. Therefore, Matcha tea infusions have been shown to be a valuable source of antioxidants that can be used in the daily diet. Full article

Matcha—Japanese powdered tea—is a variety of green tea (Camellia sinensis L.), one of the most popular beverages in the world. Due to the unique way it is grown, it contains high concentrations of health-promoting phytochemicals. The aim of this study was to determine the basic nutritional and phenolic composition of dry matcha green tea powder. The fibre content was determined according to the enzymatic–gravimetric method. Crude protein was measured by the Kjeldahl method. The total fat content was measured by the Soxhlet method, and the fatty acid profile was defined by the GC method. The determination of the phenolic acid and caffeine content was performed using high-performance liquid chromatography. The total fibre content of matcha was 56.1 g/100 g, with 52.8 g/100 g (94.1% of total fibre) of insoluble dietary fibre and 3.3 g/100 g of soluble fibre (5.9% of total fibre). The total protein content was 17.3 g/100 g. The total fat content in dry matcha was 7.285 g/100 g, comprising varying proportions of individual fatty acids, the highest ones being those of linoleic acid and α-linolenic acid. The caffeine content of matcha tea was 2213.492 µg/g. With regard to phenolic acids, the highest content was estimated for gallic acid (252.3755 µg/g). Matcha showed a particularly high content of total dietary fibre, with a predominance of the insoluble fraction. Matcha was found to be a valuable source of plant protein and unsaturated fatty acids, mostly of the omega-3 fatty acid family. Full article