Tea is a widely consumed beverage and has many important physiological properties and potential health benefits. In this study, a novel method based on supercritical fluid chromatography coupled with mass spectrometry...Tea is a widely consumed beverage and has many important physiological properties and potential health benefits. In this study, a novel method based on supercritical fluid chromatography coupled with mass spectrometry (SFC-MS) was developed to simultaneously determine 11 amino acids in different types of tea (green teas, Oolong tea, black tea and Pu-erh tea). The separation conditions for the analysis of the selected amino acids including the column type, temperature and backpressure as well as the type of additive, were carefully optimized. The best separation of the 11 amino acids was obtained by adding water (5%, v/v) and trifluoroacetic acid (0.4%, v/v) to the organic modifier (methanol). Finally, the developed SFC-MS method was fully validated and successfully applied to the determination of these amino acids in six different tea samples. Good linearity (r ≥ 0.993), precision (RSDs≤ 2.99%), accuracy (91.95%-107.09%) as well as good sample stability were observed. The limits of detection ranged from 1.42 to 14.69 ng/mL, while the limits of quantification were between 4.53 and 47.0 ng/mL. The results indicate that the contents of the 11 amino acids in the six different tea samples are greatly influenced by the degree of fermentation. The proposed SFC-MS method shows a great potential for further investigation of tea varieties.展开更多
Coronaviruses caused an outbreak pandemic disease characterized by a severe acute respiratory distress syndrome leading to the infection of more than 200 million patients and the death of more than 4 million individua...Coronaviruses caused an outbreak pandemic disease characterized by a severe acute respiratory distress syndrome leading to the infection of more than 200 million patients and the death of more than 4 million individuals.The primary treatment is either supportive or symptomatic.Natural products have an important role in the development of various drugs.Thus,screening of natural compounds with reported antiviral activities can lead to the discovery of potential inhibitory entities against coronaviruses.In the current study,an in-silico molecular docking experiment was conducted on the effects of some of these natural antiviral phytoconstituents,(e.g.,procyanidin B2,theaflavin,quercetin,ellagic acid,caffeoylquinic acid derivatives,berginin,eudesm-1β,6α,11-triol and arbutin),on the crystal structure of SARS-CoV-2 main protease(PDB ID:6w63)using AutoDock-Vina software.Many of the docked compounds revealed good binding affinity,with procyanidin B2(–8.6 Kcal/mol)and theaflavin(–8.5 Kcal/mol)showing a better or similar binding score as the ligand(–8.5 Kcal/mol).Molecular dynamics simulations were carried out at 100 ns and revealed that procyanidin B2 forms a more stable complex with SARS-CoV-2 main protease than theaflavin.Procyanidin B2,theaflavin,and 4,5-dicaffeoylquinic acid were evaluated for toxicity by ProTox-II webserver and were non-toxic according to the predicted LD50 values and safe on different organs and pathways.Additionally,these phytoconstituents showed good ADME properties and acceptable lipophilicity,as evaluated using WLOGP.Amongst the tested compounds,procyanidin B2 showed the highest lipophilic value.It is worth mentioning that these natural inhibitiors of SARS-CoV-2 main protease are components of green and black tea that can be used as a supporting supplement for COVID patients or as potential nuclei for further drug design and development campaigns.展开更多
This study was conducted in context to preserve tomato healthiness and to improve its yield in field.It aimed to assess some effects of non-aerated sheep manure and water jacinthe(Eichhornia crassipes)composts teas.It...This study was conducted in context to preserve tomato healthiness and to improve its yield in field.It aimed to assess some effects of non-aerated sheep manure and water jacinthe(Eichhornia crassipes)composts teas.It specifically consisted to evaluate two teas effects on tomato’s:(a)A.solani foliar disease,(b)yield and(c)mycorrhization intensity.The experiments were conducted according to completely randomized Fisher block with four repetitions.Three treatments were considered:plants receiving non-aerated sheep manure compost tea(TCFM),plants receiving non-aerated water jacinthe compost tea(TCJE),and control plants(T0)without compost tea application.The experiments were repeated twice.Teas application started at four-leaf stage of tomato plants.It was weekly and insured by manual foliar spraying and watering of the plants.To determine the preventive suppressive effects of compost teas,three days after its initial application,plants were artificially inoculated by foliar spraying with Alternaria solani sporal suspension.Data were analyzed with R software.Tukey Contrasts test at 5%threshold was used to compare means.Results showed that TCFM was the most suppressive on A.solani and also had enhanced tomato yield in field.Both teas did not have a meaningful effect on tomato mycorrhization intensity.These results showed that TCFM can serve as biopesticide and biofertilizer in tomato culture.展开更多
Tea is one of the most consumed beverages in the world and its quality is influenced by geographical origin and production methods. This study focuses on the volatile aroma components of 38 tea products from China, Ja...Tea is one of the most consumed beverages in the world and its quality is influenced by geographical origin and production methods. This study focuses on the volatile aroma components of 38 tea products from China, Japan, Indonesia, Sri-Lanka, and Chinese Taipei;among them 7 green teas, 13 oolong teas, and 18 black teas. The volatiles were extracted from the infusions using PorapakQ-resin, concentrated, and analyzed by gas chromatography-mass spectrometry. The components were identified by authentic reference compounds or preliminary based on their mass spectra. Different manufacturing processes yield different blends of aroma compounds. In general, the contents of total volatiles, aliphatics, aromatics, and terpenoids increased with the fermentation degree, whereas jasmine lactone and indole were the highest in oolong teas. Some particular manufacturing processes, for example, the use of tea leaves infested by the tea green leafhopper, lead to higher contents of volatiles in final products as in Oriental Beauty oolong tea. The relative peak areas determined for 82 volatiles were the basis for the statistical analysis and highlight the potential of multivariate analysis to distinguish tea samples of different categories.展开更多
This research was aimed to evaluate the total antioxidant status(TAS)and the total oxidant status(TOS)of galactagogues and herbal teas.Galactagogues and herbal teas used for other purposes were sold in the market for ...This research was aimed to evaluate the total antioxidant status(TAS)and the total oxidant status(TOS)of galactagogues and herbal teas.Galactagogues and herbal teas used for other purposes were sold in the market for breastfeeding mothers and babies.Tea infusions were prepared by following brewing recipe on the package.TAS(mmol/L)and TOS(mol/L)were measured and oxidative stress indices(OSI)were calculated.TAS values of the mixed-herbal teas in granule form that sold as still tea were found to be higher((1.5±0.00)–(1.7±0.14)mmol/L)compared to other galactagogue tea types(P<0.05).TAS value of the mixed-herbal tea in classic tea bag was(1.0±0.06)mmol/L while the TAS value of the vitamin added mixed-herbal tea was(3.0±0.00)mmol/L(P<0.05).The TAS and TOS values of the night-teas were simultaneously found to be higher compared to herbal teas(P<0.05).Besides,the highest OSI values among herbal teas was chamomile tea(6.96).In conclusion,antioxidant/oxidant status of galactagogues and other herbal teas might vary according to their form(powder or granule),type,variety of herbs in the composition,and the brand.Moreover,some galactagogues and other herbal teas have high levels of oxidant activity as well as antioxidant activity.Also,it seems that vitamin addition is important for balancing antioxidant/oxidant status of all tea types.展开更多
Colon cancer is the third leading cause of death in the US. Selected herbal teas and spices may reduce incidence of chronic diseases, including cancer. The objective of this study was to identify the effect of strawbe...Colon cancer is the third leading cause of death in the US. Selected herbal teas and spices may reduce incidence of chronic diseases, including cancer. The objective of this study was to identify the effect of strawberry leaf, raspberry leaf, hibiscus teas and cinnamon on azoxymethane (AOM)-induced aberrant crypt foci (ACF) in Fisher 344 male rats. After acclimatization period (1 wk), 49 male weanling rats were divided into 16 groups. Control (CON) group fed AIN-93G diet;15 treatment groups were administered control diet + strawberry leaf tea (STW), raspberry leaf tea (RAS), hibiscus tea (HIB), cinnamon (CIN), strawberry leaf tea + cinnamon (STW + CIN), raspberry leaf tea + cinnamon, (RAS + CIN), hibiscus tea + cinnamon (HIB + CIN), and strawberry leaf tea + raspberry leaf tea + hibiscus tea + cinnamon in combination (COM) at 2 levels each (teas added at 1% and 2%;CIN added at 2.5% and 5%). Rats received 24 mg/kg body weight AOM in saline s/c at 7 and 8 weeks of age. Animals received experimental diets until sacrificed by CO2 asphyxiation (17 weeks of age). ACF were enumerated in colons. Hepatic antioxidant enzymes were determined;superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and glutathione (GH). Treatment groups had reduction in ACF compared to CON (154). Lowest ACF observed in HIB 2% + CIN 5% (13.16) with 91.45% reduction compared to CON. ACF observed in treatment groups administered teas and cinnamon combinations were lower than those administered teas singly. SOD and CAT activities in rats administered treatment diets were higher than CON (13.63 U/mL, 0.95 umol·min-l·ml-1). Rats administered COM (20.65 U/mL) had highest SOD activity. CAT activity was 51.27% higher in rats administered HIB 2% (1.96 umol·min-l·ml-1). GPX activity ranged from 7.26 (STW 1% + CIN 2.5%) to 9.59 (STW 2%) umol·min-l·ml-1. Results suggest that herbal teas and spices may reduce the risk of colon cancer and improve antioxidant status;regular consumption may provide beneficial health effects.展开更多
A comparative deliberation has been considered among three Indian processed teas (black, green and white) in respect to their prevalence of some secondary metabolites, antioxidant ability (ABTS and DPPH assay), nutrit...A comparative deliberation has been considered among three Indian processed teas (black, green and white) in respect to their prevalence of some secondary metabolites, antioxidant ability (ABTS and DPPH assay), nutritional properties, inorganic elemental profile and bactericidal efficiency. Green and white tea, incidence of total phenol, total flavonoids, proanthocyanidins and tannin are higher than the black. ABTS and DPPH study reveals lower IC50 occurred in Green tea. Green tea is enriched in Na, Fe, Mg, and Mn content;black is rich in K, Ca and white has highest Zn. Total sugar and free amino acid are highest in white tea;total protein content is almost same in all three types. Green tea is enriched with vitamin C. Antimicrobial asset is experienced against Bacillus subtilis, Staphylococcus aureus (gram + ve) and Escherichia coli and Pseudomonas aeruginosa (gram?-?ve) bacteria. Study revealed that green tea has higher antimicrobial activity than the other two, though higher inhibitory effect of black tea might be attributed to the presence of substantial amount of tannin. Statistical evaluation reflects that in all organic and aqueous extracts, secondary metabolites correlate linearly with DPPH and ABTS assays but are not consistent with bactericidal efficiency in all cases.展开更多
Colon cancer is the third leading cause of death in the US. Herbal teas and spices may reduce the incidence of chronic diseases, including colon cancer. The objectives of this study were to determine the chemopreventi...Colon cancer is the third leading cause of death in the US. Herbal teas and spices may reduce the incidence of chronic diseases, including colon cancer. The objectives of this study were to determine the chemopreventive effects of herbal teas and cinnamon in an in-vitro cell model and to evaluate the inhibitory effects of selected extracts on enzymes associated with inflammatory disease. Effects of raspberry leaf (0.5 - 2.0 mg/mL), strawberry leaf (0.4 - 1.0 mg/mL), hibiscus flower (4.0 - 10.0 mg/mL) and cinnamon (400 - 1500 μg/mL) were evaluated for cytotoxicity, induction of caspase and DNA fragmentation in colon cancer (Caco-2) cells to determine possible chemopreventive effects. Effects of extracts on inhibition of cyclooxygenase-2 (COX-2) were also measured to determine possible anti-inflammatory potential. Caco-2 cells were obtained from American Type Culture Collection (ATCC) and maintained in Dulbecco’s Modified Eagle’s Medium with 10% fetal bovine serum. As concentrations of tea increased, LDH release from Caco-2 cells increased, with cytotoxicity ranging from 1% - 80% (hibiscus flower 1.0 mg/mL and strawberry leaf (1.0 mg/mL) for teas. All extract concentrations of herbal teas and cinnamon were able to enhance caspase-3 activity with lowest activity (4.4 mmol/ min/mL) observed in the lowest concentration of cinnamon (400 μg/mL) and highest activity (6.0 mmol/min/mL) seen in the highest concentration of raspberry leaf (2 mg/mL). Tea and spice extracts were able to induce apoptosis in Caco-2 cells exhibited by increased DNA fragmentation (expressed as enrichment factor). Enrichment factor ranged from 1.0 - 1.5 (raspberry leaf 1.0 mg/mL and hibiscus 10.0 mg/mL). Teas and cinnamon exhibited anti-inflammatory potential by inhibiting COX-2 by 0.6% - 8.0% (raspberry leaf 1.0 mg/mL and strawberry leaf 0.8 mg/mL). The results suggest that herbal teas and cinnamon may have significant benefits in chemoprevention.展开更多
A study was carried out to quantitatively estimate the L-theanine content in 19 teas commercially available in the Kenyan market by High Performance Liquid Chromatography (HPLC). The test tea samples analyzed were gre...A study was carried out to quantitatively estimate the L-theanine content in 19 teas commercially available in the Kenyan market by High Performance Liquid Chromatography (HPLC). The test tea samples analyzed were green (n = 4), black (n = 8) and flavored (n = 7) teas from different origins viz., Kenya (n = 4), Uganda (n = 2), Tanzania (n = 5), Rwanda (n = 4), Cameroon (n = 1) and Sri-Lanka (n = 2) commercially available in the Kenyan market. The estimated Limit of Detection (LOD) of the current method was 0.01% L-theanine. The L-theanine content ranged from below the detection limit (<0.01% L-theanine) to 1.60% L-theanine on a dry weight (d.w) basis. Statistically significant differences (p < 0.05) were observed in the L-theanine contents of black, green and flavoured teas. Rwandan green tea contained the highest L-theanine content with 1.60% d.w. whereas six of the seven flavoured teas had very low theanine levels (<0.01%) that could not be quantified by the current method.展开更多
Herb teas, Arabian jasmine, Balsam pear, Barley grass, Guava, Hardy rubber tree, Japanese persimmon, Jobs tears, Oolong tea, Puerh tea and Wolofberry have been consumed as beverages for health in Asia. Oxidative stres...Herb teas, Arabian jasmine, Balsam pear, Barley grass, Guava, Hardy rubber tree, Japanese persimmon, Jobs tears, Oolong tea, Puerh tea and Wolofberry have been consumed as beverages for health in Asia. Oxidative stress induces various diseases. Some of them, Arabian jasmine, Guava, Hardy rubber tree, Japanese per-simmon, Oolong tea and Puerh tea, have high total polyphenol content and antioxidant activities. Herbs and herbal polyphenols pay in controlling oxidation and prevent the damage by oxidation. These results showed that some of them, Arabian jasmine, Guava, Hardy rubber tree, Japanese persimmon, Oolong tea and Puerh tea, have high total polyphenol content and antioxidant activities. It has been demonstrated that high total polyphenol content in the herb teas provides high antioxidant activities.展开更多
Coffees and teas are beverages that are both exceptionally rich in antioxidant molecules, and are also both associated with beneficial health effects. Thus although the quality characteristics of these beverages are c...Coffees and teas are beverages that are both exceptionally rich in antioxidant molecules, and are also both associated with beneficial health effects. Thus although the quality characteristics of these beverages are conventionally assessed on the basis of their sensory properties, their antioxidant contents represent an additional and increasingly valued attribute of quality based on their contributions to healthy diets. Both beverages are prepared by hot water extraction of a pure plant-derived product, and thus their compositions can potentially change quite rapidly as a result of oxidation in contact with air. Oxidative processes often proceed via free radical intermediates, and sometimes also result in the formation of stable radical end-products;thus EPR spectroscopy is a convenient technique for investigating some of the various free radical reactions that occur in these beverages. This paper reviews progress that has been made in elucidating free radical processes that occur during the preparation and storage of coffees and teas, and the results are discussed in terms of quality criteria of the beverages.展开更多
Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity ag...Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity against E.coli O157:H7 than using either alone.This study aimed to explore responses underlying the antibacterial mechanisms of kojic acid and tea polyphenols from the gene level.The functional enrichment analysis by comparing kojic acid and tea polyphenols individually or synergistically against E.coli O157:H7 found that acid resistance systems in kojic acid were activated,and the cell membrane and genomic DNA were destructed in the cells,resulting in“oxygen starvation”.The oxidative stress response triggered by tea polyphenols inhibited both sulfur uptake and the synthesis of ATP,which affected the bacteria's life metabolic process.Interestingly,we found that kojic acid combined with tea polyphenols hindered the uptake of iron that played an essential role in the synthesis of DNA,respiration,tricarboxylic acid cycle.The results suggested that the iron uptake pathways may represent a novel approach for kojic acid and tea polyphenols synergistically against E.coli O157:H7 and provided a theoretical basis for bacterial pathogen control in the food industry.展开更多
Obesity is associated with gut dysbiosis and metabolic endotoxin.Junshanyinzhen tea extract(JSTE)reduced fat accumulation and body weight in obese mice.However,the effects and mechanism of JSTE in preventing obesity w...Obesity is associated with gut dysbiosis and metabolic endotoxin.Junshanyinzhen tea extract(JSTE)reduced fat accumulation and body weight in obese mice.However,the effects and mechanism of JSTE in preventing obesity were unclear.Therefore,we used different doses of JSTE(75,150 and 300 mg/(kg·day))to evaluate the effect on high-fat diet(HFD)-induced rats under 8 weeks of intervention.Here,our results showed that JSTE could significantly reduce body weight gain,blood lipid levels and fat accumulation,improve fatty damage in liver tissue(P<0.05).In addition,JSTE increased the expression of intestinal tight junction proteins(P<0.05),relieved metabolic endotoxemia(P<0.05)and chronic low-grade inflammation in HFD rats.Sequencing of fecal samples showed that JSTE could effectively reverse the microbial diversity and the ratio of Firmicutes to Bacteroidetes to normal levels in HFD-fed rats.Desulfovibrioceae and Erysipelotrichaceae,which are positively related to obesity,were decreased by JSTE intervention(P<0.05).while Bifidobacteriaceae,Bacteroidaceae,Akkermansia,and Clostridium,which are negatively related to obesity,were increased.Together,these results suggested that JSTE might effectively prevent obesity by modulating gut microbiota dysbiosis,intestinal barrier dysfunction,metabolic endotoxemia and chronic low-grade infl ammation in HFD-induced rats.展开更多
基金the financial support from China Postdoctoral Science Foundation(2018M643205)
文摘Tea is a widely consumed beverage and has many important physiological properties and potential health benefits. In this study, a novel method based on supercritical fluid chromatography coupled with mass spectrometry (SFC-MS) was developed to simultaneously determine 11 amino acids in different types of tea (green teas, Oolong tea, black tea and Pu-erh tea). The separation conditions for the analysis of the selected amino acids including the column type, temperature and backpressure as well as the type of additive, were carefully optimized. The best separation of the 11 amino acids was obtained by adding water (5%, v/v) and trifluoroacetic acid (0.4%, v/v) to the organic modifier (methanol). Finally, the developed SFC-MS method was fully validated and successfully applied to the determination of these amino acids in six different tea samples. Good linearity (r ≥ 0.993), precision (RSDs≤ 2.99%), accuracy (91.95%-107.09%) as well as good sample stability were observed. The limits of detection ranged from 1.42 to 14.69 ng/mL, while the limits of quantification were between 4.53 and 47.0 ng/mL. The results indicate that the contents of the 11 amino acids in the six different tea samples are greatly influenced by the degree of fermentation. The proposed SFC-MS method shows a great potential for further investigation of tea varieties.
文摘Coronaviruses caused an outbreak pandemic disease characterized by a severe acute respiratory distress syndrome leading to the infection of more than 200 million patients and the death of more than 4 million individuals.The primary treatment is either supportive or symptomatic.Natural products have an important role in the development of various drugs.Thus,screening of natural compounds with reported antiviral activities can lead to the discovery of potential inhibitory entities against coronaviruses.In the current study,an in-silico molecular docking experiment was conducted on the effects of some of these natural antiviral phytoconstituents,(e.g.,procyanidin B2,theaflavin,quercetin,ellagic acid,caffeoylquinic acid derivatives,berginin,eudesm-1β,6α,11-triol and arbutin),on the crystal structure of SARS-CoV-2 main protease(PDB ID:6w63)using AutoDock-Vina software.Many of the docked compounds revealed good binding affinity,with procyanidin B2(–8.6 Kcal/mol)and theaflavin(–8.5 Kcal/mol)showing a better or similar binding score as the ligand(–8.5 Kcal/mol).Molecular dynamics simulations were carried out at 100 ns and revealed that procyanidin B2 forms a more stable complex with SARS-CoV-2 main protease than theaflavin.Procyanidin B2,theaflavin,and 4,5-dicaffeoylquinic acid were evaluated for toxicity by ProTox-II webserver and were non-toxic according to the predicted LD50 values and safe on different organs and pathways.Additionally,these phytoconstituents showed good ADME properties and acceptable lipophilicity,as evaluated using WLOGP.Amongst the tested compounds,procyanidin B2 showed the highest lipophilic value.It is worth mentioning that these natural inhibitiors of SARS-CoV-2 main protease are components of green and black tea that can be used as a supporting supplement for COVID patients or as potential nuclei for further drug design and development campaigns.
基金We thank the Ministry of High Education and Scientific Research of Mali,and the Laval University of Quebec for financing this studyWe also thank the Rural Polytechnic Institute(IPR/IFRA)of Mali for collaboration.
文摘This study was conducted in context to preserve tomato healthiness and to improve its yield in field.It aimed to assess some effects of non-aerated sheep manure and water jacinthe(Eichhornia crassipes)composts teas.It specifically consisted to evaluate two teas effects on tomato’s:(a)A.solani foliar disease,(b)yield and(c)mycorrhization intensity.The experiments were conducted according to completely randomized Fisher block with four repetitions.Three treatments were considered:plants receiving non-aerated sheep manure compost tea(TCFM),plants receiving non-aerated water jacinthe compost tea(TCJE),and control plants(T0)without compost tea application.The experiments were repeated twice.Teas application started at four-leaf stage of tomato plants.It was weekly and insured by manual foliar spraying and watering of the plants.To determine the preventive suppressive effects of compost teas,three days after its initial application,plants were artificially inoculated by foliar spraying with Alternaria solani sporal suspension.Data were analyzed with R software.Tukey Contrasts test at 5%threshold was used to compare means.Results showed that TCFM was the most suppressive on A.solani and also had enhanced tomato yield in field.Both teas did not have a meaningful effect on tomato mycorrhization intensity.These results showed that TCFM can serve as biopesticide and biofertilizer in tomato culture.
基金This study was supported by a project“From Shizuoka to the world:Research and development of next-generation bottled tea drinks and tea extracts”of Shizuoka Prefecture and Shizuoka City Collaboration of Regional Entities for the Advancement of Technological Excellence,Japan Science and Technology Agency(JST).
文摘Tea is one of the most consumed beverages in the world and its quality is influenced by geographical origin and production methods. This study focuses on the volatile aroma components of 38 tea products from China, Japan, Indonesia, Sri-Lanka, and Chinese Taipei;among them 7 green teas, 13 oolong teas, and 18 black teas. The volatiles were extracted from the infusions using PorapakQ-resin, concentrated, and analyzed by gas chromatography-mass spectrometry. The components were identified by authentic reference compounds or preliminary based on their mass spectra. Different manufacturing processes yield different blends of aroma compounds. In general, the contents of total volatiles, aliphatics, aromatics, and terpenoids increased with the fermentation degree, whereas jasmine lactone and indole were the highest in oolong teas. Some particular manufacturing processes, for example, the use of tea leaves infested by the tea green leafhopper, lead to higher contents of volatiles in final products as in Oriental Beauty oolong tea. The relative peak areas determined for 82 volatiles were the basis for the statistical analysis and highlight the potential of multivariate analysis to distinguish tea samples of different categories.
文摘This research was aimed to evaluate the total antioxidant status(TAS)and the total oxidant status(TOS)of galactagogues and herbal teas.Galactagogues and herbal teas used for other purposes were sold in the market for breastfeeding mothers and babies.Tea infusions were prepared by following brewing recipe on the package.TAS(mmol/L)and TOS(mol/L)were measured and oxidative stress indices(OSI)were calculated.TAS values of the mixed-herbal teas in granule form that sold as still tea were found to be higher((1.5±0.00)–(1.7±0.14)mmol/L)compared to other galactagogue tea types(P<0.05).TAS value of the mixed-herbal tea in classic tea bag was(1.0±0.06)mmol/L while the TAS value of the vitamin added mixed-herbal tea was(3.0±0.00)mmol/L(P<0.05).The TAS and TOS values of the night-teas were simultaneously found to be higher compared to herbal teas(P<0.05).Besides,the highest OSI values among herbal teas was chamomile tea(6.96).In conclusion,antioxidant/oxidant status of galactagogues and other herbal teas might vary according to their form(powder or granule),type,variety of herbs in the composition,and the brand.Moreover,some galactagogues and other herbal teas have high levels of oxidant activity as well as antioxidant activity.Also,it seems that vitamin addition is important for balancing antioxidant/oxidant status of all tea types.
文摘Colon cancer is the third leading cause of death in the US. Selected herbal teas and spices may reduce incidence of chronic diseases, including cancer. The objective of this study was to identify the effect of strawberry leaf, raspberry leaf, hibiscus teas and cinnamon on azoxymethane (AOM)-induced aberrant crypt foci (ACF) in Fisher 344 male rats. After acclimatization period (1 wk), 49 male weanling rats were divided into 16 groups. Control (CON) group fed AIN-93G diet;15 treatment groups were administered control diet + strawberry leaf tea (STW), raspberry leaf tea (RAS), hibiscus tea (HIB), cinnamon (CIN), strawberry leaf tea + cinnamon (STW + CIN), raspberry leaf tea + cinnamon, (RAS + CIN), hibiscus tea + cinnamon (HIB + CIN), and strawberry leaf tea + raspberry leaf tea + hibiscus tea + cinnamon in combination (COM) at 2 levels each (teas added at 1% and 2%;CIN added at 2.5% and 5%). Rats received 24 mg/kg body weight AOM in saline s/c at 7 and 8 weeks of age. Animals received experimental diets until sacrificed by CO2 asphyxiation (17 weeks of age). ACF were enumerated in colons. Hepatic antioxidant enzymes were determined;superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and glutathione (GH). Treatment groups had reduction in ACF compared to CON (154). Lowest ACF observed in HIB 2% + CIN 5% (13.16) with 91.45% reduction compared to CON. ACF observed in treatment groups administered teas and cinnamon combinations were lower than those administered teas singly. SOD and CAT activities in rats administered treatment diets were higher than CON (13.63 U/mL, 0.95 umol·min-l·ml-1). Rats administered COM (20.65 U/mL) had highest SOD activity. CAT activity was 51.27% higher in rats administered HIB 2% (1.96 umol·min-l·ml-1). GPX activity ranged from 7.26 (STW 1% + CIN 2.5%) to 9.59 (STW 2%) umol·min-l·ml-1. Results suggest that herbal teas and spices may reduce the risk of colon cancer and improve antioxidant status;regular consumption may provide beneficial health effects.
文摘A comparative deliberation has been considered among three Indian processed teas (black, green and white) in respect to their prevalence of some secondary metabolites, antioxidant ability (ABTS and DPPH assay), nutritional properties, inorganic elemental profile and bactericidal efficiency. Green and white tea, incidence of total phenol, total flavonoids, proanthocyanidins and tannin are higher than the black. ABTS and DPPH study reveals lower IC50 occurred in Green tea. Green tea is enriched in Na, Fe, Mg, and Mn content;black is rich in K, Ca and white has highest Zn. Total sugar and free amino acid are highest in white tea;total protein content is almost same in all three types. Green tea is enriched with vitamin C. Antimicrobial asset is experienced against Bacillus subtilis, Staphylococcus aureus (gram + ve) and Escherichia coli and Pseudomonas aeruginosa (gram?-?ve) bacteria. Study revealed that green tea has higher antimicrobial activity than the other two, though higher inhibitory effect of black tea might be attributed to the presence of substantial amount of tannin. Statistical evaluation reflects that in all organic and aqueous extracts, secondary metabolites correlate linearly with DPPH and ABTS assays but are not consistent with bactericidal efficiency in all cases.
文摘Colon cancer is the third leading cause of death in the US. Herbal teas and spices may reduce the incidence of chronic diseases, including colon cancer. The objectives of this study were to determine the chemopreventive effects of herbal teas and cinnamon in an in-vitro cell model and to evaluate the inhibitory effects of selected extracts on enzymes associated with inflammatory disease. Effects of raspberry leaf (0.5 - 2.0 mg/mL), strawberry leaf (0.4 - 1.0 mg/mL), hibiscus flower (4.0 - 10.0 mg/mL) and cinnamon (400 - 1500 μg/mL) were evaluated for cytotoxicity, induction of caspase and DNA fragmentation in colon cancer (Caco-2) cells to determine possible chemopreventive effects. Effects of extracts on inhibition of cyclooxygenase-2 (COX-2) were also measured to determine possible anti-inflammatory potential. Caco-2 cells were obtained from American Type Culture Collection (ATCC) and maintained in Dulbecco’s Modified Eagle’s Medium with 10% fetal bovine serum. As concentrations of tea increased, LDH release from Caco-2 cells increased, with cytotoxicity ranging from 1% - 80% (hibiscus flower 1.0 mg/mL and strawberry leaf (1.0 mg/mL) for teas. All extract concentrations of herbal teas and cinnamon were able to enhance caspase-3 activity with lowest activity (4.4 mmol/ min/mL) observed in the lowest concentration of cinnamon (400 μg/mL) and highest activity (6.0 mmol/min/mL) seen in the highest concentration of raspberry leaf (2 mg/mL). Tea and spice extracts were able to induce apoptosis in Caco-2 cells exhibited by increased DNA fragmentation (expressed as enrichment factor). Enrichment factor ranged from 1.0 - 1.5 (raspberry leaf 1.0 mg/mL and hibiscus 10.0 mg/mL). Teas and cinnamon exhibited anti-inflammatory potential by inhibiting COX-2 by 0.6% - 8.0% (raspberry leaf 1.0 mg/mL and strawberry leaf 0.8 mg/mL). The results suggest that herbal teas and cinnamon may have significant benefits in chemoprevention.
文摘A study was carried out to quantitatively estimate the L-theanine content in 19 teas commercially available in the Kenyan market by High Performance Liquid Chromatography (HPLC). The test tea samples analyzed were green (n = 4), black (n = 8) and flavored (n = 7) teas from different origins viz., Kenya (n = 4), Uganda (n = 2), Tanzania (n = 5), Rwanda (n = 4), Cameroon (n = 1) and Sri-Lanka (n = 2) commercially available in the Kenyan market. The estimated Limit of Detection (LOD) of the current method was 0.01% L-theanine. The L-theanine content ranged from below the detection limit (<0.01% L-theanine) to 1.60% L-theanine on a dry weight (d.w) basis. Statistically significant differences (p < 0.05) were observed in the L-theanine contents of black, green and flavoured teas. Rwandan green tea contained the highest L-theanine content with 1.60% d.w. whereas six of the seven flavoured teas had very low theanine levels (<0.01%) that could not be quantified by the current method.
文摘Herb teas, Arabian jasmine, Balsam pear, Barley grass, Guava, Hardy rubber tree, Japanese persimmon, Jobs tears, Oolong tea, Puerh tea and Wolofberry have been consumed as beverages for health in Asia. Oxidative stress induces various diseases. Some of them, Arabian jasmine, Guava, Hardy rubber tree, Japanese per-simmon, Oolong tea and Puerh tea, have high total polyphenol content and antioxidant activities. Herbs and herbal polyphenols pay in controlling oxidation and prevent the damage by oxidation. These results showed that some of them, Arabian jasmine, Guava, Hardy rubber tree, Japanese persimmon, Oolong tea and Puerh tea, have high total polyphenol content and antioxidant activities. It has been demonstrated that high total polyphenol content in the herb teas provides high antioxidant activities.
文摘Coffees and teas are beverages that are both exceptionally rich in antioxidant molecules, and are also both associated with beneficial health effects. Thus although the quality characteristics of these beverages are conventionally assessed on the basis of their sensory properties, their antioxidant contents represent an additional and increasingly valued attribute of quality based on their contributions to healthy diets. Both beverages are prepared by hot water extraction of a pure plant-derived product, and thus their compositions can potentially change quite rapidly as a result of oxidation in contact with air. Oxidative processes often proceed via free radical intermediates, and sometimes also result in the formation of stable radical end-products;thus EPR spectroscopy is a convenient technique for investigating some of the various free radical reactions that occur in these beverages. This paper reviews progress that has been made in elucidating free radical processes that occur during the preparation and storage of coffees and teas, and the results are discussed in terms of quality criteria of the beverages.
基金supported by National Natural Science Foundation of China(31972021)R&D Projects in Key Areas of Guangdong Province(2019B020212003)+4 种基金the Science and Technology Program of Guangzhou,China(202206010177)Guangdong key research and development program(2021B0202060001)Foshan and agricultural academy cooperation projectGuangdong Modern Agriculture project(2022KJ117)Aquatic Products Center Project of GAAS。
文摘Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity against E.coli O157:H7 than using either alone.This study aimed to explore responses underlying the antibacterial mechanisms of kojic acid and tea polyphenols from the gene level.The functional enrichment analysis by comparing kojic acid and tea polyphenols individually or synergistically against E.coli O157:H7 found that acid resistance systems in kojic acid were activated,and the cell membrane and genomic DNA were destructed in the cells,resulting in“oxygen starvation”.The oxidative stress response triggered by tea polyphenols inhibited both sulfur uptake and the synthesis of ATP,which affected the bacteria's life metabolic process.Interestingly,we found that kojic acid combined with tea polyphenols hindered the uptake of iron that played an essential role in the synthesis of DNA,respiration,tricarboxylic acid cycle.The results suggested that the iron uptake pathways may represent a novel approach for kojic acid and tea polyphenols synergistically against E.coli O157:H7 and provided a theoretical basis for bacterial pathogen control in the food industry.
基金supported by National Modern Agricultural Industry Technology System(CARS-23)Yueyang Yellow Tea Product Innovation Research Project(2018xny-js053).
文摘Obesity is associated with gut dysbiosis and metabolic endotoxin.Junshanyinzhen tea extract(JSTE)reduced fat accumulation and body weight in obese mice.However,the effects and mechanism of JSTE in preventing obesity were unclear.Therefore,we used different doses of JSTE(75,150 and 300 mg/(kg·day))to evaluate the effect on high-fat diet(HFD)-induced rats under 8 weeks of intervention.Here,our results showed that JSTE could significantly reduce body weight gain,blood lipid levels and fat accumulation,improve fatty damage in liver tissue(P<0.05).In addition,JSTE increased the expression of intestinal tight junction proteins(P<0.05),relieved metabolic endotoxemia(P<0.05)and chronic low-grade inflammation in HFD rats.Sequencing of fecal samples showed that JSTE could effectively reverse the microbial diversity and the ratio of Firmicutes to Bacteroidetes to normal levels in HFD-fed rats.Desulfovibrioceae and Erysipelotrichaceae,which are positively related to obesity,were decreased by JSTE intervention(P<0.05).while Bifidobacteriaceae,Bacteroidaceae,Akkermansia,and Clostridium,which are negatively related to obesity,were increased.Together,these results suggested that JSTE might effectively prevent obesity by modulating gut microbiota dysbiosis,intestinal barrier dysfunction,metabolic endotoxemia and chronic low-grade infl ammation in HFD-induced rats.