Polyphenolic compounds, antioxidant capacity, and quinone reductase activity of an aqueous extract of Ardisia compressa in comparison to mate (Ilex paraguariensis) and green (Camellia sinensis) teas

Aqueous extracts of the leaves of Ardisia compressa (AC) have been used in folk medicine to treat various liver disorders including liver cancer. The objective of this study was to partially characterize and determine the total polyphenol content, antioxidant capacity, and quinone reductase activity of A. compressa tea in comparison to mate (Ilex paraguariensis, MT) and green (Camellia sinensis,GT) teas. Total polyphenol content, antioxidant capacity, and phase II enzyme induction capacity were measured by the modified Folin-Ciocalteu, ORAC, and quinone reductase (QR) assays, respectively. The major polyphenols in AC were not catechins. HPLC retention times and standard spikes of AC indicated the presence of gallic acid, epicatechin gallate, ardisin and kaempferol. Using catechin as standard, the total polyphenol value of AC (36.8 +/- 1.1 mg/mg DL) was significantly lower than GT (137.2 +/- 5.8 mg equivalent of (+)-catechin/mg dried leaves, DL) and MT (82.1 +/- 3.8 mg/mg DL) (P < 0.001). Antioxidant capacity (AC, 333; GT, 1346; MT, 1239 mmol Trolox equivalents/g DL) correlated with total polyphenol values (r(2) = 0.86, P < 0.01). AC (4.5-12.5 microg/mL) induced QR enzyme, in Hepa1c1c7 cells, up to 15%. MT and GT showed no induction at the concentrations tested (0.5-10.5 and 0.5-12.5 mg/mL, respectively). These results suggest that AC has a different mechanism of protection against cytotoxicity that is not related to its antioxidant capacity. Further studies are needed to determine such mechanisms and to explore its potential as a chemopreventive or therapeutic agent.     

Characterization of the constituents and antioxidant activity of Brazilian green tea (Camellia sinensis var. assamica IAC-259 cultivar) extracts

Freeze-dried extracts from Camellia sinensis var. assamica IAC-259 cultivar named Brazilian green tea were prepared by hot water and ultrasound-assisted extractions using leaves harvested in spring and summer. Their caffeine and catechin contents were measured by high performance liquid chromatography-diode array detector. The antioxidant activity of the major green tea compounds and Brazilian green tea extracts was evaluated using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The levels of caffeine were higher in the summer samples (p < 0.05); otherwise, there were no significant variations related to the catechin contents between spring and summer samples. The sonication method using water/acetone as solvent had a high efficiency to extract not only epigallocatechin gallate but also epicatechin gallate (p < 0.05). Antioxidant activities of the Brazilian green tea extracts were not significantly different among seasons and extraction systems. The antioxidant data (IC50) of the Brazilian green tea extracts showed a significant correlation with their epigallocatechin gallate and epicatechin gallate contents (p < 0.05).     

Inhibition of pathogenic bacterial adhesion by acidic polysaccharide from green tea (Camellia sinensis)

An acidic polysaccharide CS-F2 from Camellia sinensis was examined to characterize its anti-adhesive effects against pathogenic bacteria, most notably Helicobacter pylori, Propionibacterium acnes, and Staphylococcus aureus. CS-F2 showed marked inhibitory activity against the pathogen-mediated hemagglutination with a minimum inhibitory concentration (MIC) between 0.01 and 0.1 mg/mL, which is lower than the previously reported MIC values for Panax ginseng and Artemisia capillaris. The inhibitory effects of CS-F2 on the adhesion of H. pylori to AGS adenocarcinoma gastric epithelial cells, or P. acnes and S. aureus to NIH 3T3 fibroblast cells, were further assessed resulting in MIC values between 0.063 and 0.13 mg/mL. Importantly, CS-F2 showed no inhibitory effects against Lactobacillus acidophilus, Escherichia coli, or Staphylococcus epidermidis. Our results suggest that CS-F2, which is a pectin-type polysaccharide with a molecular weight of approximately 8.0 x 10(4) Da, may exert a selective anti-adhesive effect against certain pathogenic bacteria, while exerting no effects against beneficial and commensal bacteria.     

Immunostimulating activity of a crude polysaccharide derived from green tea (Camellia sinensis) extract

Green tea extract is well-known to reduce the risk of a variety of diseases. Here, we investigated the immunostimulating activity of tea polysaccharide (TPS), one of the main components in green tea extract. The water extracts from mature or immature tea leaves were precipitated by using ethanol at room temperature. The sediment was washed with ethanol and acetone alternately and then dried. We used the phagocytic activity of macrophage-like cells as an indicator of immune function activation. Chemical components were analyzed by HPLC. The immunostimulating activity of TPS from immature leaves extract was higher than that of TPS from mature leaves, and its activities were dependent on the content of strictinin in the leaf extract. Futhermore, a mixture of catechin and TPS that removed polyphenols did not increase the immunostimulating activity. These results suggest that the catechin-polysaccharide complex is a very important molecule in the immunomodulating activity of tea extracts.     

Total polyphenol content and antioxidant capacity of commercially available tea (Camellia sinensis) in Argentina

Tea, Camellia sinensis (L.) O. Kuntze (Theaceae) is cultivated in Argentina in the northeastern region (provinces of Misiones and Corrientes), between 26 degrees and 28 degrees south latitude, the southernmost area of the world where tea is cultivated. The objective of this work was to determine the total polyphenol content and the in vitro antioxidant capacity of green and black tea cultivated and industrialized in Argentina. Twelve samples of eight brands were analyzed. The total polyphenol content was determined according to the International Organization for Standardization method (ISO) 14502-1 for the determination of substances characteristic of green and black tea. The antioxidant capacity was determined by the ferric thiocyanate method (FTC) and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free-radical scavenging assay. Green tea showed a higher polyphenol content than black tea. The total polyphenol concentration in green tea was found to vary from 21.02 +/- 1.54 to 14.32 +/- 0.45% of gallic acid equivalents (GAE), whereas in black tea, the polyphenol content ranged from 17.62 +/- 0.42 to 8.42 +/- 0.55% of GAE (P < 0.05). A similar profile was observed for the antioxidant capacity determined by both methods. The antioxidant activities were well correlated with the total polyphenol content (r (2) = 0.9935 for the ferric thiocyanate method and r (2) = 0.9141 for the 1,1-diphenyl-2-picrylhydrazyl free-radical scavenging assay). This is the first systematic screening for the quantification of polyphenols and antioxidant activity in tea commercialized in Argentine markets. The results obtained herein allow one to conclude that Argentine tea is of very good quality when compared to teas from other sources.     

Pigments in green tea leaves (Camellia sinensis) suppress transformation of the aryl hydrocarbon receptor induced by dioxin

Environmental contaminants such as dioxins enter the body mainly through diet and cause various toxicities through transformation of the aryl hydrocarbon receptor (AhR). We previously reported that certain natural flavonoids at the dietary level suppress the AhR transformation induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). In this study, we identified lutein and chlorophyll a and b from green tea leaves as the novel antagonists for AhR. These active compounds suppressed AhR transformation dose-dependently with the 50% inhibitory concentration (IC(50)) values against 0.1 nM TCDD-induced AhR transformation at 3.2, 5.0, and 5.9 microM, respectively. (-)-Epigallocatechin gallate, which is the most abundant flavonoid in green tea leaves, also showed stronger suppressive effects than did other major tea components, with the IC(50) value of 1.7 microM. Thus, these pigments of green tea leaves have the potential to protect from dioxin toxicity through the suppression of AhR transformation.     

不同品种乌龙茶种植后土壤肥力和茶叶品质的变化

本研究以毛蟹(C.sinensis cv.Maoxie)、本山(C.sinensis cv.Benshan)、梅占(C.sinensis cv.Meizhan)3个乌龙茶品种为研究对象,分析不施肥条件下茶树根部土壤养分随种植年限的变化,以及茶叶品质的变化。结果表明,不同茶树的根部土壤p H值均随茶树种植年限的增长而呈现下降趋势。不同茶树根部土壤的有机质及有效磷含量达到Ⅰ级肥力;0年取样的茶树土壤碱解氮含量为Ⅰ级肥力,不施肥种植1~2年后均为Ⅱ级肥力;土壤速效钾含量在茶树0年取样时为Ⅰ级肥力,不施肥种植1年后毛蟹根部土壤为Ⅲ级肥力,本山和梅占则为Ⅱ级肥力,2年后均为Ⅲ级肥力。茶树叶片品质分析结果表明,随着不施肥种植时间的延长,茶叶中茶多酚、茶氨酸、咖啡碱的含量呈现下降趋势。同一种茶树在不同种植年限间,茶多酚含量的变化较为微弱,而茶氨酸、咖啡碱含量则呈显著差异。不同种植年限下茶树叶片中表没食子儿茶素没食子酸酯、表儿茶素没食子酸酯与表没食子儿茶素含量及其品质指数均随着不施肥种植时间的延长而呈下降趋势,且同一种茶树不同种植年限间的变化率均呈显著差异。     

Development of new antioxidant active packaging films based on ethylene vinyl alcohol copolymer (EVOH) and green tea extract

Ethylene vinyl alcohol copolymer (EVOH) films containing green tea extract were successfully produced by extrusion. The films were brown and translucent, and the addition of the extract increased the water and oxygen barrier at low relative humidity but increased the water sensitivity, the glass transition temperature, and the crystallinity of the films and improved their thermal resistance. An analysis by HPLC revealed that the antioxidant components of the extract suffered partial degradation during extrusion, reducing the content of catechin gallates and increasing the concentration of free gallic acid. Exposure of the films to various food simulants showed that the liquid simulants increased their capacity to reduce DPPH(?) and ABTS(?+) radicals. The release of green tea extract components into the simulant monitored by HPLC showed that all compounds present in the green tea extract were partially released, although the extent and kinetics of release were dependent on the type of food. In aqueous food simulants, gallic acid was the main antioxidant component released with partition coefficient values ca. 200. In 95% ethanol (fatty food simulant) the K value for gallic acid decreased to 8 and there was a substantial contribution of catechins (K in the 1000 range) to a greatly increased antioxidant efficiency. Kinetically, gallic acid was released more quickly than catechins, owing to its faster diffusivity in the polymer matrix as a consequence of its smaller molecular size, although the most relevant effect is the plasticization of the matrix by alcohol, increasing the diffusion coefficient >10-fold. Therefore, the materials here developed with the combination of antioxidant substances that constitute the green tea extract could be used in the design of antioxidant active packaging for all type of foods, from aqueous to fatty products, the compounds responsible for the protection being those with the higher compatibility with the packaged product.     

Metabolite profiling using (1)H NMR spectroscopy for quality assessment of green tea, Camellia sinensis (L.)

A set of 191 green teas from different countries was collected and analyzed by (1)H NMR. It was proposed to establish if the teas could be discriminated according to the country of origin or with respect to quality. Both principal component analysis (PCA) and cluster analysis were applied to the data. Some separation of Chinese and non-Chinese teas was observed. The present results did not allow allocation of samples to individual countries, but cluster analysis suggested that it might be possible with an augmented sample set. The PCA did show a separation between the Longjing type (highest quality Chinese tea) and most other Chinese teas and indicated some metabolites that could be responsible for the difference. Longjing teas showed higher levels of theanine, gallic acid, caffeine, epigallocatechin gallate, and epicatechin gallate and lower levels of epigallocatechin when compared with other teas. These compounds have been mentioned previously in connection with quality, but it was also shown that higher levels of theogallin (5-galloyl quinic acid), theobromine, 2-O-(beta-l-arabinopyranosyl)-myo-inositol and some minor sugar-containing compounds were found in Longjing teas while higher levels of fatty acids and sucrose were found in the other teas. These new markers could prove to be useful for the authentication of bulk tea.     

The use of catechins as biochemical markers in diversity studies of tea (Camellia sinensis)

The concentrations of catechins in a Kenyan tea germplasm collection of 102 accessions were determined by HPLC. Total green leaf catechin concentrations and the ratio of dihydroxylated to trihydroxylated catechins were used to establish genetic differentiation in the germplasm. Upon multivariate analysis, accumulation of the various catechins separated the tea clones into 3 major and 5 minor groups according to their phylogenetic origins. The Cambod teas had the highest ratio (7:10) followed by China teas (3:5) while Assam teas had the lowest ratio (1:4). This biochemical differentiation indicates that there is potential for broadening the genetic base of the mainly Assam teas in Kenya (90%) with the putative China and Cambod teas.     

包装方式和材料对调理脆肉鲩鱼片冷藏过程品质的影响

为延缓脆肉鲩鱼片贮藏过程中腐败变质,并延长货架期。以紫苏叶水提物浸泡腌制的新鲜脆肉鲩鱼片为原料,研究包装方式和包装材料在4℃条件下对鱼片品质的影响。结果表明:气调包装鱼片菌落总数最少、普通包装菌落总数增长最快,气调包装样品冷藏15 d菌落总数平均为5.61 log[CFU/g],未超过水产品规定的货架期终点;冷藏末期气调包装样品汁液流失率、挥发性盐基氮(total volatile base-nitrogen,TVB-N)值和硫代巴比妥酸(thiobarbituric acid,TBA)值均低于真空包装和普通包装,其中PVC材料气调包装样品汁液流失率第15天达到5.07%,TVB-N值为13.91 mg/100 mg,低于国家规定的二级鲜度,TBA值比真空包装和普通包装分别低16.40%和46.46%。气调包装样品质构降低程度比其他组慢,其中,冷藏末期硬度较另外2组分别高出26.41%和27.08%;不同包装材料样品硬度、汁液流失率、TBA值、感官分值差异显著(P0.05),其中高阻隔性NY/EVOH/PET复合材料保鲜效果最好。综合各指标变化,气调包装和高阻隔性材更有利于调理脆肉鲩鱼片冷藏过程的品质保持。研究结果为调理脆肉鲩鱼片冷藏包装应用提供理论参考。     

Differentiation of tea (Camellia sinensis) varieties and their geographical origin according to their metal content

The metal content of 46 tea samples, including green, black, and instant teas, was analyzed. Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, Sr, Ti, and Zn were determined by ICP-AES. Potassium, with an average content of 15145.4 mg kg(-1) was the metal with major content. Calcium, magnesium, and aluminum had average contents of 4252.4, 1978.2, and 1074.0 mg kg(-1), respectively. The average amount of manganese was 824.8 mg kg(-1). There were no clear differences between the metal contents of green and black teas. Pattern recognition methods such as principal component analysis (PCA), linear discriminant analysis (LDA), and artificial neural networks (ANN), were applied to differentiate the tea types. LDA and ANN provided the best results in the classification of tea varieties. These chemometric procedures were also useful for distinguishing between Asian and African teas and between the geographical origin of different Asian teas.     

Comparison of antioxidant and antimicrobial activities of tilia (Tilia argentea Desf ex DC), sage (Salvia triloba l.), and black tea (Camellia sinensis) extracts

The antioxidant activity of the water extract of Tilia argentea Desf ex DC was determined by the thiocyanate method. The antioxidant activity of the water extract increased with the increasing amount of lyophilized extract (50-400 microg) added into the linoleic acid emulsion. Statistically significant effect was determined in 100 microg and higher amounts. Antioxidant activities of water extracts of tilia (Tilia argentea Desf ex DC), sage (Salvia triloba L.), and two Turkish black teas commercially called Rize tea and young shoot tea (Camellia sinensis) were compared. For comparison studies, 100 microg portions of extracts were added into test samples. All samples were able to show statistically significant antioxidant effect. Both of the tea extracts showed highest antioxidant activities, nevertheless, differences between tilia and sage and tilia and tea were not statistically significant (for both cases p > 0.05). Like antioxidant activity, the reducing power of water extract of Tilia argentea Desf ex DC was also concentration dependent. Even in the presence of 50 microg of extract, the reducing power was significantly higher than that of the control (p < 0.05) in which there was no extract. Unlike antioxidant activity, the highest reducing power activity was shown by sage extract. Among the tea extracts, young shoot extract was the most effective one, however, it had significantly lower activity than sage (p < 0.05). Although tea flower had the lowest reducing power activity, it was higher than that of tilia. But this difference was not statistically significant (p > 0.05). From these results, we could suggest that although the reducing power of a substance may be an indicator of its potential antioxidant activity, there may not always be a linear correlation between these two activities. In addition, antimicrobial activities of each of the above extracts were studied by disk diffusion methods on different test microorganisms. None of the extracts showed antibacterial activity on the studied microorganisms.     

Determination of tea polyphenols and caffeine in tea flowers (Camellia sinensis) and their hydroxyl radical scavenging and nitric oxide suppressing effects

The native occurrence of tea polyphenols, namely, (-)-epicatechin, (+)-catechin, (-)-epigallocatechin 3-gallate, (-)-epicatechin, and (-)-epicatechin 3-gallate, and caffeine in tea flowers was assessed by an isocratic HPLC procedure. The levels of total catechins and caffeine were determined in tea flowers collected from 10 different species of Camellia sinensis. The results showed the levels of total catechin ranged from 10 to 38 mg/g, whereas the level of caffeine ranged from 3 to 8 mg/g. Levels of catechins and caffeine in tea leaves and various teas were also determined and ranged from 2 to 126 mg/g and from 23 to 49 mg/g, respectively. Both tea flower and tea leaf extracts exert their strong hydroxyl radical scavenging effects in the Fenton reaction system and nitric oxide suppressing effects in LPS-induced RAW 264.7 cells. Most tea flowers contain less caffeine, but comparable amounts of total catechins, compared to tea leaves and teas. The present study demonstrates that both tea flowers and tea leaves contain appreciable amounts of catechins and caffeine. It is likely that tea flowers might be useful for making alternative tea beverages.     

薄膜气调包装对枇杷果实冷藏期间呼吸和品质性状的影响

通过对呼吸速率、总可溶性固形物、可滴定酸、pH值、果肉硬度、维生素C、失重率和品质及感官指标的变化进行分析，研究了薄膜气调包装对枇杷(Eriobotrya japonica Lindl.，品种：解放钟）果实冷藏期间呼吸和品质特性的影响，气调包装用的薄膜为低密度聚乙烯薄膜(LDPE，厚度20 μm)，以打孔的低密度聚乙烯薄膜包装为对照。结果表明，低密度聚乙烯薄膜包装枇杷果实后，3～4 d后可维持一个相对稳定的适宜枇杷贮藏的O₂和CO₂的气体浓度，即CO₂(4.8±0.67)%，O₂(11.5±0.85)%；薄膜气调包装结合低温可明显地降低枇杷果实的呼吸速率；薄膜气调包装可以最大限度地减小冷藏期间的枇杷果实的失重率、果肉硬度、维生素C、总可溶性固形物、可滴定酸和固酸比的变化，维持枇杷的新鲜品质，延长货架期。因此，低密度聚乙烯薄膜（LDPE，厚度20 μm）气调包装可用于枇杷的贮藏保鲜。     

Effects of ferrous sulfate with sulfuric acid on tea (Camellia sinensis (L.) O. Kuntz) soil environment

In brown tea soil, the effects of ferrous sulfate with sulfuric acid on soil environment and tea plant (Camellia sinensis (L.) O. Kuntz) growth were examined by enzyme activity, microbe quantity, nutrients in rhizosphere soil, and the nutrients and dry matter weight in the tea plant. We found that the pH value in the brown soil was significantly decreased by ferrous sulfate with sulfuric acid treatments, compared with the value in unfertilized control (CK) or sulfuric acid treatments. The acid phosphatase activities of 3 g kg^–1 ferrous sulfate with 0.05 mL L^–1 sulfuric acid were increased by 210.53%. Interestingly, the quantities of fungi were increased by 19.76% and the bacteria and actinomyces were decreased in the CK treatment. Specifically, the nitrogen and magnesium in rhizosphere soil and leaves were significantly increased by the low concentrations of ferrous sulfate with 0.05 mL L^–1 sulfuric acid, whereas the dry matter weight under 3 g kg^–1 ferrous sulfate with 0.05 mL L^–1 sulfuric acid was increased by 36.22% in the CK treatment. Thus, we concluded that ferrous sulfate with sulfuric acid affected not only the soil environment but also the growth of tea plants. Our results suggested that the concentration of ferrous sulfate at 3 g kg^–1 soil diluted in 0.05 mL L^–1 sulfuric acid could be considered a good soil conditioner to make a suitable soil environment for tea production.     

The coupling effect of water and fertilizer on the growth of tea plants [Camellia sinensis (L.) O. Kuntz]

Water and fertilizer are the two main factors promoting the rapid growth of tea plants (Camellia sinensis). Using two-year-old rooted cutting of Wuniuzao (Camellia sinensis) as experimental materials, “311-B” D-saturation optimization design was carried out using 5, 4, and 4 levels of irrigation regimes, fertilizer nitrogen, and fertilizer phosphorus, with six replications. The raw date obtained was used of quadratic regression fitting for the plant height, new-tip length and dry matter weight. The coupling effects of these three factors [nitrogen (N0, water, and phosphorus (P)] on dry matter weight were significant. The effect order of single factor on dry matter weight was N>water>P, while the interactive effect order on the dry matter weight was N and water>P and water>N and P. An optimal combination with 0.485 g·pot^?1 N, 0.274 g·pot^?1 P, and once every 4-5 days of watering was proposed for the highest tea dry matter yield.     

Effect of yerba mate (Ilex paraguariensis) tea on topoisomerase inhibition and oral carcinoma cell proliferation

Tea flavonoids have antitopoisomerase activity and can inhibit cell proliferation. The objectives of this study were to determine the phenolic content of yerba mate tea products (MT) (Ilex paraguariensis) and evaluate their capacity to inhibit topoisomerase I (Topo I) and II (Topo II) activities and oral carcinoma cell proliferation. Total polyphenols of aqueous extracts of dried MT leaves were measured by the Folin-Ciocalteau assay, using chlorogenic (CH) and gallic (GA) acids as standards. Topoisomerase inhibition was determined by a clone-forming assay, which uses yeast (Saccharomyces cerevisiae) strains as a model. Controls included dimethyl sulfoxide (1.66%); camptothecin (50 microg/mL), a Topo I inhibitor; and amsacrine (100 microg/mL), a Topo II inhibitor. Cytotoxicity studies were conducted using a nontumorigenic human keratinocyte cell line HaCaT and two human squamous cancer cell lines (SCC-61 and OSCC-3). MT was found to be a rich source of phenolic compounds. Total polyphenol content of various commercially available traditional MT products ranged from 236 to 490 mg equiv of CH/g of dry leaves. Such levels were significantly different among products depending on their origin (P < 0.001). Higher anti-topoisomerase II activity was observed against JN394t(2-4) strain for Nobleza Gaucha MT (IC50 = 0.43 microg equiv of CH) in comparison to GA (IC50 = 112 mM) and CH (IC50 > 1500 mM). MT showed catalytic anti-topoisomerase activity against Topo II but not against Topo I. In addititon, MT exhibited dose-dependent cytotoxicity against all squamous cell lines tested. In comparison to premalignant cell line HaCaT [28 microg equiv of (+)-catechin mL(-1)], the cell line SCC-61 [21 microg equiv of (+)-catechin mL(-1)] was the most sensitive to MT, resulting in 50% inhibition of net cell growth. It is concluded that MT is rich in phenolic constituents and can also inhibit oral cancer proliferation. The effect on cancer cell proliferation may be mediated via inhibition of topoisomerase II. The lack of correlation between polyphenol content and the inhibition of topoisomerases suggests that the effect of MT on topoisomerase inhibition may be due to other still unidentified biologically active phytochemicals constituents.     

Inhibition of gastrointestinal lipolysis by green tea, coffee, and gomchui (Ligularia fischeri) tea polyphenols during simulated digestion

Green tea, coffee, and gomchui (Ligularia fischeri) tea, which are rich in polyphenols, may exhibit antiobesity effects by inhibiting pancreatic lipase. However, the bioavailability of some polyphenols is poor due to either degradation or absorption difficulties in the gastrointestinal tract, thus making their beneficial effects doubtful. This study was conducted to evaluate the inhibitory effect of three beverages on lipolysis and the contribution of their major polyphenols during simulated digestion. During simulated digestion, gomchui tea was the most potent at inhibiting gastrointestinal lipolysis, whereas green tea was the least potent. The strongest lipase inhibitor among purified major polyphenols was a green tea polyphenol, (-)-epigallocatechin gallate (EGCG, IC(50) = 1.8 ± 0.57 μM), followed by di-O-caffeoylquinic acid isomers (DCQA, IC(50) from 12.7 ± 4.5 to 40.4 ± 2.3 μM), which are gomchui tea polyphenols. However, the stability of DCQA was greater than that of EGCG when subjected to simulated digestion. Taken together, gomchui tea, which has DCQA as the major polyphenol, showed stronger lipolysis inhibitory activity during simulated digestion compared to both green tea and coffee.