Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are cruci...Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are crucial due to the horizontal transfer of these natural products from PA-producing plants to soil and subsequently absorbed by plant roots.This study firstly investigated the sorption/desorption behaviors of PAs/PANOs in tea plantation soils with distinct characteristics.Sorption amounts for seneciphylline(Sp)and seneciphylline-N-oxide(SpNO)in three acidic soils ranged from 2.9 to 5.9μg/g and 1.7 to 2.8μg/g,respectively.Desorption percentages for Sp and SpNO were from 22.2%to 30.5%and 36.1%to 43.9%.In the mixed PAs/PANOs systems,stronger sorption of PAs over PANOs was occurred in tested soils.Additionally,the Freundlich models more precisely described the sorption/desorption isotherms.Cation exchange capacity,sand content and total nitrogen were identified as major influencing factors by linear regression models.Overall,the soils exhibiting higher sorption capacities for compounds with greater hydrophobicity.PANOs were more likely to migrate within soils and be absorbed by tea plants.It contributes to the understanding of environmental fate of PAs/PANOs in tea plantations and provides basic data and clues for the development of PAs/PANOs reduction technology.展开更多
A rare sesquiterpene of hawkteasesquioid A(1),featuring a novel 5/6/5 tricyclic system containing a 6,5-spiroketal motif,was isolated from the bark of Litsea coreana Lévl.var.lanuginosa(hawk tea).The structure of...A rare sesquiterpene of hawkteasesquioid A(1),featuring a novel 5/6/5 tricyclic system containing a 6,5-spiroketal motif,was isolated from the bark of Litsea coreana Lévl.var.lanuginosa(hawk tea).The structure of this compound was elucidated based on the high-resolution electrospray ionization mass spectrometry(HRESIMS),one-dimensional(1D)and two-dimensional(2D)nuclear magnetic resonance(NMR)spectroscopy,and single-crystal X-ray diffraction data.The cytotoxicity of this compound was assessed on the A549,HT-29,and SW1990 cell lines.展开更多
The water conservancy construction and soil and water conservation projects in New China have reshaped the tea industry landscape in Xinyang City of Henan Province from multiple dimensions.In terms of hydraulic techno...The water conservancy construction and soil and water conservation projects in New China have reshaped the tea industry landscape in Xinyang City of Henan Province from multiple dimensions.In terms of hydraulic technology,engineering systems represented by the Nanwan Irrigation District redefined the watershed irrigation pattern,while the application of modern agricultural technologies such as sprinkler and electric irrigation accelerated the shift from traditional experience to scientific management in tea garden practices.Ecologically,systematic soil and water management significantly improved growing conditions,making it possible for tea cultivation to break through the traditional geographical limitation of"tea does not grow north of the Huai River."This integrated governance model not only laid the foundation for the northward expansion of Xinyang's tea industry across the Huai River but also facilitated the transition toward scale and intensification through improved irrigation infrastructure and the breeding of cold-resistant tea varieties.Ultimately,driven by the tripartite interactive mechanism of"engineering governance-ecological improvement-spatial expansion,"the tea industry in Xinyang achieved a historic leap from traditional production to modern intensive development.展开更多
Currently,cultivated tea plants are classified into three varieties,namely,Camellia sinensis var.sinensis,C.sinensis var.assamica,and C.sinensis var.kucha.Three tea varieties made green teas(TVGTs)are widely consumed ...Currently,cultivated tea plants are classified into three varieties,namely,Camellia sinensis var.sinensis,C.sinensis var.assamica,and C.sinensis var.kucha.Three tea varieties made green teas(TVGTs)are widely consumed worldwide.However,a comparative investigation of the beneficial effects,mechanism,and characteristic compounds of TVGTs has not been reported.Here,three representative tea plant varieties,namely,C.sinensis var.sinensis cv.Fuding(FD),C.sinensis var.assamica cv.Yunkang 10(YK),and C.sinensis var.kucha(KC),planted in the same garden,were used to make green teas utilizing the same standard procedure.Our findings show that the TVGTs effectively improved hyperglycemia,obesity,dyslipidemia,fatty liver,and mesenteric artery(MA)hypercontractility in mice with diabetes and obesity induced by a high-fat diet(HFD)after 11-and 22-week interventions,with YK being the most effective at 22 weeks.Liver lipidomics indicated that the TVGTs restored the glycerophospholipid and sphingolipid balance and reduced triglycerides,with YK demonstrating superior effects.The TVGTs,particularly YK,suppressed triglyceride synthesis through the ARV1-FXR-SHP-SREBP-1c pathway.A chemical profile analysis revealed that YK green tea had enriched active compounds,including caffeine,quinic acid,L-theanine,gallic acid,and catechins,compared with FD and KC green teas,which may contribute to ameliorating diabetic dyslipidemia via synergistic action.As a representative tea variety of C.sinensis var.assamica,YK green tea was found to be superior to the other two green teas in preventing and treating diabetic dyslipidemia,especially with long term consumption.These data provide important information for tea plant breeders and tea consumers.展开更多
Cold stress widely impairs the quality and yield of tea plants. The miR164 family and its target NAC transcription factor have been identified as crucial regulators in response to cold stress. However, the role of miR...Cold stress widely impairs the quality and yield of tea plants. The miR164 family and its target NAC transcription factor have been identified as crucial regulators in response to cold stress. However, the role of miR164 and CsNAC in cold tolerance in tea plants was little understood. In our study, the expression level of CsMIR164a was significantly reduced under cold stress and significantly and negatively correlated with that of CsNAC1.5' RACE and GUS histochemical assays showed that CsNAC1 was cleaved by CsMIR164a. The CsMIR164a-silenced tea leaves promoted the expression levels of CsNAC1 and CsCBFs and exhibited greater cold tolerance. Also, the overexpression of CsNAC1 enhanced cold tolerance in transgenic Arabidopsis plants by promoting the expression levels of AtCBFs. In contrast, the heterologous overexpression of CsMIR164a in Arabidopsis decreased the expression level of AtNACs and AtCBFs and thus impaired cold tolerance. Additionally, silencing of CsNAC1 impaired the expression levels of CsCBFs, resulting in greater cold sensitivity in tea leaves. Our present study demonstrated that the miR164a-CsNAC1 module may play a negative role in the cold tolerance of tea plants via the CsCBF-dependent pathway.展开更多
In recent years,the new-style tea-drinking market has expanded rapidly.With the upgrading of consumer demands and the younger generation becoming the primary consumer group,the space experience centered around the“th...In recent years,the new-style tea-drinking market has expanded rapidly.With the upgrading of consumer demands and the younger generation becoming the primary consumer group,the space experience centered around the“third space”has become a crucial strategy for brands to differentiate themselves.This research focuses on the impact mechanism of spatial scenario design on the brand value of tea-drinking brands,aiming to explore the internal relationships among the key elements of spatial design,brand perception,consumers’emotional connection,and consumption willingness,providing theoretical support and practical references for scenario-based design in the industry.Through a combination of literature research and case-analysis methods,this study systematically reviews relevant domestic and international research on scenario-based design and brand value over the past five years.It selects representative brands as cases,deeply analyzes their spatial design strategies,user feedback,and market performance,and summarizes both successful experiences and existing problems.Scenario-based design is an important means to enhance the brand value of tea-drinking brands,but it needs to follow the four-in-one design principle of“brand consistency,functional diversity,experience coherence,and cost controllability.”In the future,brands should focus on the in-depth exploration and innovative expression of cultural elements,strengthen the multi-functional attributes of spaces,and achieve seamless integration of online and offline scenarios through digital means.In addition,it is recommended to adopt modular design to reduce scenario-updating costs and increase the return on investment.This research provides a theoretical basis and practical path for the optimization of the spatial design of tea-drinking brands,and has important reference value for promoting the high-quality development of the industry.展开更多
This work aims to compare the chemical composition and anti-inflammatory effects on RAW264.7 macrophages of Keemun black tea stems and leaves.A total of 50 volatile compounds were identified in tea stems and leaves,an...This work aims to compare the chemical composition and anti-inflammatory effects on RAW264.7 macrophages of Keemun black tea stems and leaves.A total of 50 volatile compounds were identified in tea stems and leaves,and aldehydes,alcohols,and esters were the main volatile compound categories.There were 11 key volatile compounds,including geraniol,benzeneacetaldehyde,methyl salicylate,linalool,etc.contributed to distinguishing the tea stems from the tea leaves.In the quantitative and liquid chromatography-mass spectrometry(LC-MS)-based metabolomics analysis,higher contents of amino acids,monosaccharides,and quinic acids were found in stems than those in leaves.Inversely,higher contents of tea pigments,flavan-3-ols,gallic acid,purine alkaloids,and flavonol glycosides were present in tea leaves than in stems.LC-MS-based metabolomics also revealed that organic acids were the most critical non-volatile compounds responsible for the differences between tea stems and leaves.Furthermore,tea stems had better inhibiting effects of pro-inflammatory cytokines(interleukin(IL)-1βand IL-6)in lipopolysaccharide-challenged RAW264.7 macrophages than tea leaves,while no significant differences exist between leaves and stems for inhibiting the secretion of tumor necrosis factorα(TNF-α)and NO.In conclusion,our results support using Keemun black tea stems as a novel source of anti-inflammatory compounds.展开更多
This study investigated the therapeutic effects on metabolic syndrome(MetS)and the impact on the intestinal barrier and gut microbiota of Fu brick tea aqueous extracts(FTE)on MetS in rats fed with a high-fat diet(HFD)...This study investigated the therapeutic effects on metabolic syndrome(MetS)and the impact on the intestinal barrier and gut microbiota of Fu brick tea aqueous extracts(FTE)on MetS in rats fed with a high-fat diet(HFD).Here,the results showed that FTE supplement significantly reduced HFD-induced weight gain,adiposity,dyslipidemia,fasting blood glucose(FBG)increment,and non-alcoholic fatty liver disease(NAFLD).Moreover,FTE supplement resulted in a decline in lipopolysaccharide(LPS)level and attenuation of colonic inflammation and oxidative stress to protect the intestinal barrier function.FTE supplement also maintained the intestinal barrier integrity by improving histological appearance and promoting ZO-1,Occludin,and Claudin-1 protein expression levels.Meanwhile,FTE supplement alleviated the gut microbiota dysbiosis by enhancing the Firmicutes/Bacteroidetes(F/B)ratio and stimulating the colonization of probiotic bacteria such as Akkermansia,Lactobacillus,Adlercreutzia,and Bacteroides.These findings collectively suggest that Fu brick tea could alleviate MetS and MetS-associated traits with the mechanism relevant to the protection of intestinal barrier and gut microbiota regulation.展开更多
Pu-erh tea,a traditional Chinese beverage,performs an anti-obesity function,but the correlation between its components and efficacy remains unknown.Here,we screened two Pu-erh teas with significant anti-obesity effica...Pu-erh tea,a traditional Chinese beverage,performs an anti-obesity function,but the correlation between its components and efficacy remains unknown.Here,we screened two Pu-erh teas with significant anti-obesity efficacies from 11 teas.In vitro experiments revealed that lipid accumulation in L02 cells and lipid synthesis in 3T3-L1 cells were significantly better inhibited by Tea-B than Tea-A.Further in vivo experiments using model mice revealed that the differences in chemical components generated two pathways in the anti-obesity efficacy and mechanism of Pu-erh teas.Tea-A changes the histomorphology of brown adipose tissue(BAT)and increases the abundance of Coriobacteriaceae_UCG_002 and cyclic AMP in guts through high chemical contents of cyclopentasiloxane,decamethyl,tridecane and 1,2,3-trimethoxybenzene,eventually increasing BAT activation and fat browning gene expression;the high content of hexadecane and 1,2-dimethoxybenzene in Tea-B reduces white adipose tissue(WAT)accumulation and the process of fatty liver,increases the abundance of Odoribacter and sphinganine 1-phosphate,inhibits the expression of lipid synthesis and transport genes.These mechanistic findings on the association of the representative bioactive components in Pu-erh teas with the anti-obesity phenotypes,gut microbes,gut metabolite structure and anti-obesity pathways,which were obtained for the first time,provide foundations for developing functional Pu-erh tea.展开更多
Tea’s popularity and flavor are influenced by factors like cultivation and processing methods and shaping techniques also have an impact on tea flavor.This study employed targeted metabolomics and chemometrics to inv...Tea’s popularity and flavor are influenced by factors like cultivation and processing methods and shaping techniques also have an impact on tea flavor.This study employed targeted metabolomics and chemometrics to investigate how shaping techniques affect the flavor of milk-flavored white tea(MFWT).The results showed that the tea cake sample with the shortest pressing time(Y90)has the highest amino acid content and milky aroma intensity.There were variations in amino acids,catechins,and soluble sugars among MFWT samples with different shaping techniques.The total contents of amino acids and catechins in tea cake sample(Y90)were significantly lower than those in the loose tea sample(SC)and bundle-like tea sample(SG),while the total sugar content was significantly higher than that in SC(P<0.05).Additionally,the content of volatiles presenting milky aroma(VIP&OAV>1)in Y90 remained lower relative to SC and SG(P<0.05),but the proportion was not different from that in SC and SG,minimally affecting the overall flavor.The short-time pressing method might be suitable for mass production of MFWT.These findings provide insights into improving the tightness of the appearance of MFWT with minimal impact on tea flavor.展开更多
The members of the fourth subgroup of R2R3-MYB(Sg4 members)are well-known inhibitors of phenylpropanoid and lignin synthesis pathways.The C2 domain is closely related to the transcriptional inhibitory activity of Sg4 ...The members of the fourth subgroup of R2R3-MYB(Sg4 members)are well-known inhibitors of phenylpropanoid and lignin synthesis pathways.The C2 domain is closely related to the transcriptional inhibitory activity of Sg4 members.Phosphorylation modification enhances the transcriptional inhibitory activity of Sg4 members.Here,we identified a phosphorylation site on the C2 domain of Cs MYB4a from tea plants(Camellia sinensis).A mitogen-activated protein kinase(MAPK),named Cs MPK3-2,phosphorylated this site on the C2 domain of Cs MYB4a.Further experiments revealed that phosphorylation of Cs MYB4a weakened its ability to inhibit the gene expression of PAL,C4H,and 4CL in the phenylpropanoid pathway and activated the expression of transcription factor YABBY5,maintaining the adaxial-abaxial polarity of the leaf.Knocking out Nt YAB5 in Cs MYB4a transgenic tobacco partially repaired the leaf wrinkling phenotype caused by Cs MYB4a.The C1 domain exhibited an activation function when the C2 domain of Cs MYB4a was phosphorylated by Cs MPK3-2,causing this reversal phenomenon.These results enrich our understanding of the regulatory diversity of Sg4 members.展开更多
To explore the volatile profiles and the contents of ten bioactive components(polyphenols and caffeine) of sun-dried Pu-erh tea leaves from ancient tea plants on Bulang Mountain,17 samples of three tea varieties were ...To explore the volatile profiles and the contents of ten bioactive components(polyphenols and caffeine) of sun-dried Pu-erh tea leaves from ancient tea plants on Bulang Mountain,17 samples of three tea varieties were analyzed by headspace-solid phase microextraction-gas chromatography-mass spectrometry(HS-SPME-GC-MS) and high-performance liquid chromatography(HPLC).A total of 75 volatile components were tentatively identified.Laomaner(LME),Laobanzhang(LBZ),and other teas on Bulang Mountain(BL) contained 70,53,and 71 volatile compounds,respectively.Among the volatile compounds,alcohols(30.2%-45.8%),hydrocarbons(13.7%-17.5%),and ketones(12.4%-23.4%) were qualitatively the most dominant volatile compounds in the different tea varieties.The average content of polyphenol was highest in LME(102.1 mg/g),followed by BL(98.7 mg/g) and LBZ(88.0 mg/g),while caffeine showed the opposite trend,27.3 mg/g in LME,33.5 mg/g in BL,and 38.1 mg/g in LBZ.Principal component analysis applied to both the volatile compounds and ten bioactive components showed a poor separation of samples according to varieties,while partial least squares-discriminant analysis(PLS-DA) showed satisfactory discrimination.Thirty-four volatile components and five bioactive compounds were selected as major discriminators(variable importance in projection(VIP)>1) among the tea varieties.These results suggest that chromatographic data combined with multivariate analysis could provide a useful technique to characterize and distinguish the sun-dried Pu-erh tea leaves from ancient tea varieties on Bulang Mountain.展开更多
Tea flavor is a comprehensive representation of its aroma and other characteristics.The formation of volatile odor compounds during tea processing depends on a variety of enzymatic and non-enzymatic activities.(Z)-3-h...Tea flavor is a comprehensive representation of its aroma and other characteristics.The formation of volatile odor compounds during tea processing depends on a variety of enzymatic and non-enzymatic activities.(Z)-3-hexenol is considered the primary source of the green odor and is also the most important component in tea aroma,significantly affecting the overall aroma.However,the biosynthesis and accumulation of(Z)-3-hexenol during tea processing have not been fully analyzed.In this study,we found that withering treatment at different times and withering plus shaking treatment at different degrees promoted the accumulation of important volatile components of green tea odor,especially(Z)-3-hexenol by GC-MS.The RNA-seq and qRT-PCR results showed that withering and withering plus shaking treatments enhanced the expression of(Z)-3-hexenol-related genes in tea leaves,including synthetic pathway 1 genes(CsLOX3,CsHPL1,CsADH4,and CsAHD1),synthetic pathway 2 genes(CsGLU),and synthetic pathway 3 genes(CsCXEs).Correlation analysis of the key odorants and important genes in the three synthetic pathways revealed that some CsCXEs were positively correlated with green odor compounds.The in vitro enzyme activity results showed that rCsCXE3(GWHTASIV011658),and rCsCXE6(GWHTASIV031480)exhibited hydrolytic activity against three tea acetate compounds[hexyl acetate,(E)-2-hexyl acetate,and(Z)-3-hexyl acetate],resulting in the production of corresponding alcohol compounds.In summary,withering and shaking treatment during tea processing promoted the expression of CsCXE3 and CsCXE6,thereby enhancing the production of hexenol compounds.These compounds play a crucial role in increasing the green odor of tea.展开更多
Anthracnose is a devastating disease caused by Colletotrichum that significantly affects the yield and economic value of the tea plant(Camellia sinensis). However, few studies have addressed the genetic mechanism of a...Anthracnose is a devastating disease caused by Colletotrichum that significantly affects the yield and economic value of the tea plant(Camellia sinensis). However, few studies have addressed the genetic mechanism of anthracnoseresistance(AR). This study investigated the QTL associated with AR in a 'Longjing 43'×'Baijiguan'(LJ43×BJG)population. The field surveys conducted in this study led to the identification of several QTLs for AR on the linkagemap. One major QTL(qAR-12.4) accounted for 12% of the phenotypic variance explained over two years. The BSA-seq results also revealed two genomic regions, q ARChr1 on chromosome 1 and qARChr13 on chromosome 13,which showed strong correlations with AR. Time-course RNA-seq was performed on LJ43 and BJG inoculated withanthracnose at 0, 24, and 48 hours to screen for candidate genes. The results showed the gradual post-inoculationexpression of a nuclear-localized ERF transcription factor(CsERF105) within the qARChr1 locus in BJG but not inLJ43. The AR of BJG was significantly reduced after feeding with CsERF105-specific antisense oligonucleotides,suggesting that CsERF105 may be a positive regulator. The findings of this study add to our general knowledge ofthe genetic factors involved in the tea plant's AR and potential breeding targets.展开更多
The relationship between the amount of tea cream and the chemical components contents in the original green tea infusion was investigated. The results showed that the amounts of tea cream in the green tea infusions ob...The relationship between the amount of tea cream and the chemical components contents in the original green tea infusion was investigated. The results showed that the amounts of tea cream in the green tea infusions obtained from different cultivars and different parts of new shoots were varied. There were many chemical components participating in the formation of green tea cream. However, there were only the contents of caffeine （Y=0.85, P〈0.01） and polyphenols （Y=0.65, P〈0.05） in the original green tea infusion highly correlated with the amount of green tea cream. Stepwise regression analysis of overall chemical components indicated that the contents of caffeine and gallated catechins in the original green tea infusion had a significant effect （P〈0.01） on green tea cream levels. Cream （g L-1）=-172.071＋ 0.129×Ccaffeine＋0.024×Ggallated catechins （R2=0.936）. The amount of green tea cream can be predicted by the contents of gallated catechins and caffeine in the original tea infusion. Principal component analysis also indicated that catechins, minerals, and polysaccharides were the important chemical components in the formation of green tea cream.展开更多
Thirteen volatile compounds were identified from Flemingia macrophylla plants. Eight major components significantly attracted the tea green leafhoppers, Empoasca flavescens F. Based on their relative abundances, follo...Thirteen volatile compounds were identified from Flemingia macrophylla plants. Eight major components significantly attracted the tea green leafhoppers, Empoasca flavescens F. Based on their relative abundances, following synthetic blends were made for field experiments: 1) eight-component-attractant blend included Z-3-hexen-1-ol, Z-3-hexenyl acetate, Z-ocimene, Me SA, Z-3-hexenyl butyrate, dodecane, hexadecane and nonanal at 10, 10, 1, 11, 2, 6, 2 and 4 mg mL^-1 in n-hexane, respectively;2) four-component-attractant blend #1 contained hexadecane, Z-3-hexenyl acetate, Z-3-hexen-1-ol and nonanal at 2, 10, 10 and 4 mg mL^-1 in n-hexane, respectively;3) four-component-attractant blend #2 contained hexadecane, Z-3-hexenyl acetate, Z-3-hexen-1-ol and Me SA at 2, 10, 10 and 11 mg mL^-1 in n-hexane, respectively. Thymol and 1-methoxy-4-methyl-2-(1-methylethyl)-benzene, identified from Lavandula angustifolia aeration samples, significantly repelled the leafhopper as strong repellents when tested alone or in combination at 10 mg mL^-1. For field bioassays, each attractant lure was attached to a bud green sticky board hung from a bamboo stick at above tea plant level for catching the leafhoppers, whereas the repellent dispenser was tied to a tea branch inside tea clump for pushing the leafhoppers away from tea clumps. The results showed that the eight-component-attractant blend caught similar numbers of the leafhopper as did the four-component-attractant blend #1 at about 53–79 leafhoppers/trap/day, which were significantly higher than those on the hexane-control bud green sticky boards. Average leafhopper catches from un-baited sticky boards were about 51–73 leafhoppers/trap/day when pushed by the repellents placed inside tea plants, with the two-component-repellent blend being more effective than their single components. When the two-component-repellent blend was further tested with the three attractant blends in a push-pull fashion, average trap catches ranged from 62 to 92 leafhoppers/trap/day. Control efficacy on the leafhoppers within the push-pull zones increased progressively from day 1(43%) to day 5(73%). This push-pull approach might have a great potential as a green control strategy for combating the tea green leafhoppers.展开更多
Myriad evidence attests to the health-promoting benefits of tea drinking.While there are multiple factors of tea influencing the effective biological properties,tea polyphenols are the most significant and valuable co...Myriad evidence attests to the health-promoting benefits of tea drinking.While there are multiple factors of tea influencing the effective biological properties,tea polyphenols are the most significant and valuable components.The chemical characterization and physical characteristics of tea polyphenols have been comprehensively studied over the previous years.Still the emergence of new chemistry in tea,particularly the property of scavenging reactive carbonyl species(RCS)and the newly discovered flavoalkaloid compounds,has drawn increasing attention.In this review,we summarize recent findings of a new class of compounds in tea-flavonoid alkaloids(flavoalkaloids),which exist in fresh tea leaves and can be generated during the process of post-harvesting,and also postulate the formation mechanism of flavoalkaloids between catechins and theanine-derived Strecker aldehyde.Additionally,we detail the up-to-date research results of tea polyphenols regarding their ability to trap RCS and their in vivo aminated metabolites to suppress advanced glycation ends products(AGEs).We further raise questions to be addressed in the near future,including the synthetic pathways for the generation of flavoalkaloids and AGEs in fresh tea leaves before processing and the concentrations of tea polyphenols that affect their RCS scavenging capability due to their pro-oxidant nature.More intensive research is warranted to elucidate the mechanisms of action underlying the biological activity of flavoalkaloids and the pharmacological application of tea polyphenols in scavenging RCS and impeding detrimental AGEs.展开更多
Theasinensin A(TSA),a dimer of epigallocatechin gallate,has been preliminarily demonstrated to have hypoglycemia and anti-inflammatory effects.However,little information is available on its potential mechanisms of ant...Theasinensin A(TSA),a dimer of epigallocatechin gallate,has been preliminarily demonstrated to have hypoglycemia and anti-inflammatory effects.However,little information is available on its potential mechanisms of anti-diabetes.Therefore,the present study aimed to investigate the influence of TSA on glucose and lipid metabolism and gut microbiota in high-fat-diet/streptozotocin-induced diabetic mice.As result,TSA improved polydipsia,polyphagia and impaired glucose tolerance of diabetic mice,declined the fasting blood glucose and hepatic triglyceride level,and enhanced the expression at mRNA level of insulin receptor substrate,phosphoinositide 3-kinase,protein kinase B and glucagon-like peptide 1 receptor(GLP-1R)in the diabetic liver.Moreover,TSA could restore the disorder of gut microbiota of diabetic mice.High-dose(100 mg/kg)TSA showed better benefi cial effects from the blood biochemical parameters,hepatic function and gut microbiota.In general,high-dose TSA significantly modulated gut microbiota by increasing the relative abundance of Akkermansia and decreasing the relative abundances of Acetatifactor,Anaerotruncus,Pseudofl avonifactor,Oscillibacter and Clostridium clusters.The results indicated that TSA could exert an anti-diabetes effect in diabetic mice through restoring glucose homeostasis,declining hepatic steatosis,activating insulin and GLP-1 signaling pathways,and ameliorating gut microbiota dysbiosis.展开更多
Dark tea(containing Eurotium cristatum)and black tea have hypoglycemic effects.The black brick tea with fungal growth is obtained from black tea by adding E.cristatum,followed by steaming,pressing,fungal growth,and dr...Dark tea(containing Eurotium cristatum)and black tea have hypoglycemic effects.The black brick tea with fungal growth is obtained from black tea by adding E.cristatum,followed by steaming,pressing,fungal growth,and drying.However,the hypoglycemic effects of black brick tea are still unexplored.Here,we used black brick tea with fungal growth and black tea as raw materials to study their hypoglycemic effects in a hyperglycemic mice model.Both these types of black tea could lower the content of blood glucose and increase the content of hepatic glycogen by upregulating the proteins and m RNA expression of phosphatidylinositol-4,5-bisphosphate3-kinase,glycogen synthase,protein kinase B and phosphoinositidedependent protein kinase-1 and downregulating the protein and m RNA expression of glycogen synthase kinase 3β.These regulatory steps were followed by high activities of glutathione peroxidase and superoxide dismutase and low content of malondialdehyde.These teas can promote blood glucose transport and absorption by upregulating the protein and m RNA expression of insulin receptor substrate-1 and glucose transporter-2 and stimulate glycolysis by upregulating the protein and m RNA expression of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 2.Our study suggests that the black brick tea was more effective than the black tea in terms of hypoglycemic.展开更多
A bacterial artificial chromosome （BAC） library is an invaluable resource tool to initiate tea plant genomics research, and the preparation of high molecular weight （HMW） genomic DNA is a crucial first step for co...A bacterial artificial chromosome （BAC） library is an invaluable resource tool to initiate tea plant genomics research, and the preparation of high molecular weight （HMW） genomic DNA is a crucial first step for constructing a BAC Library. In order to construct a BAC library for enhancing tea plant genomics research, a new method for the preparation of tea pant high molecular weight （HMW） genomic DNA must be developed due to young tea plant leaves and shoots are notably rich in both tea polyphenols and tea polysaccharides. In this paper, a modified method for preparing high quality tea plant HMW genomi~ DNA was optimized, and the quality of tea plant genomic DNA was evaluated. The results were as follows： Critical indicators of HMW DNA preparation were the appearance of the smooth nuclei in solution （as opposed to sticky-gummy） before agarose plug solidification, non-dark colored nuclei plugs after lysis with an SDS/proteinase K solution, and the quality and quantity of HMW DNA fragments after restriction enzyme digestion. Importantly, 1% dissolved PVP-40 and 1% un-dissolved PVP-40 during the nuclei extraction steps, in conjunction with the removal of PVP-40 from the plug washing and nuclei lysis steps, were critical for achieving HWM tea plant DNA suitable for BAC library construction. Additionally, a third PFGE fraction selection step to eliminate contaminating small DNA fragments. The modifications provided parameters that may have prevented deleterious interactions from tea polyphenols and tea polysaccharides. The HMW genomic DNA produced by this new modified method has been used to successfully construct a large-insert tea plant BAC library, and thus may be suitable for BAC library construction from other plant species that contain similarly interfering compounds.展开更多
基金supported by the earmarked fund for the Modern Agro-Industry Technology Research System (No.CARS-19)the Innovative Research Team in Chinese Academy of Agricultural Sciences (No.CAAS ASTIP-2014-TRICAAS).
文摘Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are crucial due to the horizontal transfer of these natural products from PA-producing plants to soil and subsequently absorbed by plant roots.This study firstly investigated the sorption/desorption behaviors of PAs/PANOs in tea plantation soils with distinct characteristics.Sorption amounts for seneciphylline(Sp)and seneciphylline-N-oxide(SpNO)in three acidic soils ranged from 2.9 to 5.9μg/g and 1.7 to 2.8μg/g,respectively.Desorption percentages for Sp and SpNO were from 22.2%to 30.5%and 36.1%to 43.9%.In the mixed PAs/PANOs systems,stronger sorption of PAs over PANOs was occurred in tested soils.Additionally,the Freundlich models more precisely described the sorption/desorption isotherms.Cation exchange capacity,sand content and total nitrogen were identified as major influencing factors by linear regression models.Overall,the soils exhibiting higher sorption capacities for compounds with greater hydrophobicity.PANOs were more likely to migrate within soils and be absorbed by tea plants.It contributes to the understanding of environmental fate of PAs/PANOs in tea plantations and provides basic data and clues for the development of PAs/PANOs reduction technology.
文摘A rare sesquiterpene of hawkteasesquioid A(1),featuring a novel 5/6/5 tricyclic system containing a 6,5-spiroketal motif,was isolated from the bark of Litsea coreana Lévl.var.lanuginosa(hawk tea).The structure of this compound was elucidated based on the high-resolution electrospray ionization mass spectrometry(HRESIMS),one-dimensional(1D)and two-dimensional(2D)nuclear magnetic resonance(NMR)spectroscopy,and single-crystal X-ray diffraction data.The cytotoxicity of this compound was assessed on the A549,HT-29,and SW1990 cell lines.
文摘The water conservancy construction and soil and water conservation projects in New China have reshaped the tea industry landscape in Xinyang City of Henan Province from multiple dimensions.In terms of hydraulic technology,engineering systems represented by the Nanwan Irrigation District redefined the watershed irrigation pattern,while the application of modern agricultural technologies such as sprinkler and electric irrigation accelerated the shift from traditional experience to scientific management in tea garden practices.Ecologically,systematic soil and water management significantly improved growing conditions,making it possible for tea cultivation to break through the traditional geographical limitation of"tea does not grow north of the Huai River."This integrated governance model not only laid the foundation for the northward expansion of Xinyang's tea industry across the Huai River but also facilitated the transition toward scale and intensification through improved irrigation infrastructure and the breeding of cold-resistant tea varieties.Ultimately,driven by the tripartite interactive mechanism of"engineering governance-ecological improvement-spatial expansion,"the tea industry in Xinyang achieved a historic leap from traditional production to modern intensive development.
基金financially supported by the National Key Research and Development Program of China(2021YFD1601102)by a key joint grant for regional innovation from the National Natural Science Foundation of China(U19A2034)+2 种基金a key grant for University Synergy Innovation Program of Anhui Province(GXXT-2019-49)a grant from the China Agriculture Research System of MOF and MARA(CARS-19)a grant for supporting an animal core facility in Anhui Agricultural University from the Department of Sciences and Technology of Anhui Province.
文摘Currently,cultivated tea plants are classified into three varieties,namely,Camellia sinensis var.sinensis,C.sinensis var.assamica,and C.sinensis var.kucha.Three tea varieties made green teas(TVGTs)are widely consumed worldwide.However,a comparative investigation of the beneficial effects,mechanism,and characteristic compounds of TVGTs has not been reported.Here,three representative tea plant varieties,namely,C.sinensis var.sinensis cv.Fuding(FD),C.sinensis var.assamica cv.Yunkang 10(YK),and C.sinensis var.kucha(KC),planted in the same garden,were used to make green teas utilizing the same standard procedure.Our findings show that the TVGTs effectively improved hyperglycemia,obesity,dyslipidemia,fatty liver,and mesenteric artery(MA)hypercontractility in mice with diabetes and obesity induced by a high-fat diet(HFD)after 11-and 22-week interventions,with YK being the most effective at 22 weeks.Liver lipidomics indicated that the TVGTs restored the glycerophospholipid and sphingolipid balance and reduced triglycerides,with YK demonstrating superior effects.The TVGTs,particularly YK,suppressed triglyceride synthesis through the ARV1-FXR-SHP-SREBP-1c pathway.A chemical profile analysis revealed that YK green tea had enriched active compounds,including caffeine,quinic acid,L-theanine,gallic acid,and catechins,compared with FD and KC green teas,which may contribute to ameliorating diabetic dyslipidemia via synergistic action.As a representative tea variety of C.sinensis var.assamica,YK green tea was found to be superior to the other two green teas in preventing and treating diabetic dyslipidemia,especially with long term consumption.These data provide important information for tea plant breeders and tea consumers.
基金supported by the Anhui University Collaborative Innovation Project, China (GXXT-2020080)the Scientific Research Project of Anhui Provincial Colleges and Universities, China (2023AH040136)。
文摘Cold stress widely impairs the quality and yield of tea plants. The miR164 family and its target NAC transcription factor have been identified as crucial regulators in response to cold stress. However, the role of miR164 and CsNAC in cold tolerance in tea plants was little understood. In our study, the expression level of CsMIR164a was significantly reduced under cold stress and significantly and negatively correlated with that of CsNAC1.5' RACE and GUS histochemical assays showed that CsNAC1 was cleaved by CsMIR164a. The CsMIR164a-silenced tea leaves promoted the expression levels of CsNAC1 and CsCBFs and exhibited greater cold tolerance. Also, the overexpression of CsNAC1 enhanced cold tolerance in transgenic Arabidopsis plants by promoting the expression levels of AtCBFs. In contrast, the heterologous overexpression of CsMIR164a in Arabidopsis decreased the expression level of AtNACs and AtCBFs and thus impaired cold tolerance. Additionally, silencing of CsNAC1 impaired the expression levels of CsCBFs, resulting in greater cold sensitivity in tea leaves. Our present study demonstrated that the miR164a-CsNAC1 module may play a negative role in the cold tolerance of tea plants via the CsCBF-dependent pathway.
文摘In recent years,the new-style tea-drinking market has expanded rapidly.With the upgrading of consumer demands and the younger generation becoming the primary consumer group,the space experience centered around the“third space”has become a crucial strategy for brands to differentiate themselves.This research focuses on the impact mechanism of spatial scenario design on the brand value of tea-drinking brands,aiming to explore the internal relationships among the key elements of spatial design,brand perception,consumers’emotional connection,and consumption willingness,providing theoretical support and practical references for scenario-based design in the industry.Through a combination of literature research and case-analysis methods,this study systematically reviews relevant domestic and international research on scenario-based design and brand value over the past five years.It selects representative brands as cases,deeply analyzes their spatial design strategies,user feedback,and market performance,and summarizes both successful experiences and existing problems.Scenario-based design is an important means to enhance the brand value of tea-drinking brands,but it needs to follow the four-in-one design principle of“brand consistency,functional diversity,experience coherence,and cost controllability.”In the future,brands should focus on the in-depth exploration and innovative expression of cultural elements,strengthen the multi-functional attributes of spaces,and achieve seamless integration of online and offline scenarios through digital means.In addition,it is recommended to adopt modular design to reduce scenario-updating costs and increase the return on investment.This research provides a theoretical basis and practical path for the optimization of the spatial design of tea-drinking brands,and has important reference value for promoting the high-quality development of the industry.
基金supported by the Natural Science Foundation of China(32122079,32072633)Earmarked Fund for China Agriculture Research System(CARS-19)+2 种基金Anhui Key Research and Development Plan(202104b11020001)Young Elite Scientist Sponsorship Program by National CAST(2016QNRC001)High-level Introduced Talent Sponsorship Program by Anhui Agricultural University(rc352203)。
文摘This work aims to compare the chemical composition and anti-inflammatory effects on RAW264.7 macrophages of Keemun black tea stems and leaves.A total of 50 volatile compounds were identified in tea stems and leaves,and aldehydes,alcohols,and esters were the main volatile compound categories.There were 11 key volatile compounds,including geraniol,benzeneacetaldehyde,methyl salicylate,linalool,etc.contributed to distinguishing the tea stems from the tea leaves.In the quantitative and liquid chromatography-mass spectrometry(LC-MS)-based metabolomics analysis,higher contents of amino acids,monosaccharides,and quinic acids were found in stems than those in leaves.Inversely,higher contents of tea pigments,flavan-3-ols,gallic acid,purine alkaloids,and flavonol glycosides were present in tea leaves than in stems.LC-MS-based metabolomics also revealed that organic acids were the most critical non-volatile compounds responsible for the differences between tea stems and leaves.Furthermore,tea stems had better inhibiting effects of pro-inflammatory cytokines(interleukin(IL)-1βand IL-6)in lipopolysaccharide-challenged RAW264.7 macrophages than tea leaves,while no significant differences exist between leaves and stems for inhibiting the secretion of tumor necrosis factorα(TNF-α)and NO.In conclusion,our results support using Keemun black tea stems as a novel source of anti-inflammatory compounds.
基金supported by the Earmarked Fund for the Modern Agricultural Industry Technology System(CARS19),Research on Quality Chemical Characteristics and Healthy Function of Xianyang Brick Tea(2021kjc-js231)Research on Metabolite Alteration and Mechanism in Fu Brick Tea under the Action of Eurotium cristatum(31471706).
文摘This study investigated the therapeutic effects on metabolic syndrome(MetS)and the impact on the intestinal barrier and gut microbiota of Fu brick tea aqueous extracts(FTE)on MetS in rats fed with a high-fat diet(HFD).Here,the results showed that FTE supplement significantly reduced HFD-induced weight gain,adiposity,dyslipidemia,fasting blood glucose(FBG)increment,and non-alcoholic fatty liver disease(NAFLD).Moreover,FTE supplement resulted in a decline in lipopolysaccharide(LPS)level and attenuation of colonic inflammation and oxidative stress to protect the intestinal barrier function.FTE supplement also maintained the intestinal barrier integrity by improving histological appearance and promoting ZO-1,Occludin,and Claudin-1 protein expression levels.Meanwhile,FTE supplement alleviated the gut microbiota dysbiosis by enhancing the Firmicutes/Bacteroidetes(F/B)ratio and stimulating the colonization of probiotic bacteria such as Akkermansia,Lactobacillus,Adlercreutzia,and Bacteroides.These findings collectively suggest that Fu brick tea could alleviate MetS and MetS-associated traits with the mechanism relevant to the protection of intestinal barrier and gut microbiota regulation.
基金The financial support received from the Shenzhen Science and Technology Innovation Commission(KCXFZ20201221173207022,WDZC20200821141349001)Shenzhen Bay Laboratory Startup Fund(21310041,S234602003)。
文摘Pu-erh tea,a traditional Chinese beverage,performs an anti-obesity function,but the correlation between its components and efficacy remains unknown.Here,we screened two Pu-erh teas with significant anti-obesity efficacies from 11 teas.In vitro experiments revealed that lipid accumulation in L02 cells and lipid synthesis in 3T3-L1 cells were significantly better inhibited by Tea-B than Tea-A.Further in vivo experiments using model mice revealed that the differences in chemical components generated two pathways in the anti-obesity efficacy and mechanism of Pu-erh teas.Tea-A changes the histomorphology of brown adipose tissue(BAT)and increases the abundance of Coriobacteriaceae_UCG_002 and cyclic AMP in guts through high chemical contents of cyclopentasiloxane,decamethyl,tridecane and 1,2,3-trimethoxybenzene,eventually increasing BAT activation and fat browning gene expression;the high content of hexadecane and 1,2-dimethoxybenzene in Tea-B reduces white adipose tissue(WAT)accumulation and the process of fatty liver,increases the abundance of Odoribacter and sphinganine 1-phosphate,inhibits the expression of lipid synthesis and transport genes.These mechanistic findings on the association of the representative bioactive components in Pu-erh teas with the anti-obesity phenotypes,gut microbes,gut metabolite structure and anti-obesity pathways,which were obtained for the first time,provide foundations for developing functional Pu-erh tea.
基金support from the National Key Research and Development Program of China(2022YFD2101101)the Modern Agricultural(Tea)Industry Technology System of Fujian Province,China([2021]No.90)+2 种基金the Guiding Project of Science and Technology Department in Fujian Province,China(2022N0031)the Special Fund Program for Science and Technology Innovation of Fujian Agriculture and Forestry University,China(KFB23203)the Special Fund for Science and Technology Innovation of Fujian Zhang Tianfu Tea Development Foundation,China(FJZTF01)。
文摘Tea’s popularity and flavor are influenced by factors like cultivation and processing methods and shaping techniques also have an impact on tea flavor.This study employed targeted metabolomics and chemometrics to investigate how shaping techniques affect the flavor of milk-flavored white tea(MFWT).The results showed that the tea cake sample with the shortest pressing time(Y90)has the highest amino acid content and milky aroma intensity.There were variations in amino acids,catechins,and soluble sugars among MFWT samples with different shaping techniques.The total contents of amino acids and catechins in tea cake sample(Y90)were significantly lower than those in the loose tea sample(SC)and bundle-like tea sample(SG),while the total sugar content was significantly higher than that in SC(P<0.05).Additionally,the content of volatiles presenting milky aroma(VIP&OAV>1)in Y90 remained lower relative to SC and SG(P<0.05),but the proportion was not different from that in SC and SG,minimally affecting the overall flavor.The short-time pressing method might be suitable for mass production of MFWT.These findings provide insights into improving the tightness of the appearance of MFWT with minimal impact on tea flavor.
基金supported by the joint funds of National Natural Science Foundation of China(Grant Nos.U21A20232,32372756,32072621)。
文摘The members of the fourth subgroup of R2R3-MYB(Sg4 members)are well-known inhibitors of phenylpropanoid and lignin synthesis pathways.The C2 domain is closely related to the transcriptional inhibitory activity of Sg4 members.Phosphorylation modification enhances the transcriptional inhibitory activity of Sg4 members.Here,we identified a phosphorylation site on the C2 domain of Cs MYB4a from tea plants(Camellia sinensis).A mitogen-activated protein kinase(MAPK),named Cs MPK3-2,phosphorylated this site on the C2 domain of Cs MYB4a.Further experiments revealed that phosphorylation of Cs MYB4a weakened its ability to inhibit the gene expression of PAL,C4H,and 4CL in the phenylpropanoid pathway and activated the expression of transcription factor YABBY5,maintaining the adaxial-abaxial polarity of the leaf.Knocking out Nt YAB5 in Cs MYB4a transgenic tobacco partially repaired the leaf wrinkling phenotype caused by Cs MYB4a.The C1 domain exhibited an activation function when the C2 domain of Cs MYB4a was phosphorylated by Cs MPK3-2,causing this reversal phenomenon.These results enrich our understanding of the regulatory diversity of Sg4 members.
文摘To explore the volatile profiles and the contents of ten bioactive components(polyphenols and caffeine) of sun-dried Pu-erh tea leaves from ancient tea plants on Bulang Mountain,17 samples of three tea varieties were analyzed by headspace-solid phase microextraction-gas chromatography-mass spectrometry(HS-SPME-GC-MS) and high-performance liquid chromatography(HPLC).A total of 75 volatile components were tentatively identified.Laomaner(LME),Laobanzhang(LBZ),and other teas on Bulang Mountain(BL) contained 70,53,and 71 volatile compounds,respectively.Among the volatile compounds,alcohols(30.2%-45.8%),hydrocarbons(13.7%-17.5%),and ketones(12.4%-23.4%) were qualitatively the most dominant volatile compounds in the different tea varieties.The average content of polyphenol was highest in LME(102.1 mg/g),followed by BL(98.7 mg/g) and LBZ(88.0 mg/g),while caffeine showed the opposite trend,27.3 mg/g in LME,33.5 mg/g in BL,and 38.1 mg/g in LBZ.Principal component analysis applied to both the volatile compounds and ten bioactive components showed a poor separation of samples according to varieties,while partial least squares-discriminant analysis(PLS-DA) showed satisfactory discrimination.Thirty-four volatile components and five bioactive compounds were selected as major discriminators(variable importance in projection(VIP)>1) among the tea varieties.These results suggest that chromatographic data combined with multivariate analysis could provide a useful technique to characterize and distinguish the sun-dried Pu-erh tea leaves from ancient tea varieties on Bulang Mountain.
基金supported by the Natural Science Foundation of China(Grant Nos.U21A2023 and 32072621)the earmarked fund for CARS-19 and the Youth Science and Technology Talents Support Program(2020)by Anhui Association for Science and Technology(Grant No.RCTJ202010).
文摘Tea flavor is a comprehensive representation of its aroma and other characteristics.The formation of volatile odor compounds during tea processing depends on a variety of enzymatic and non-enzymatic activities.(Z)-3-hexenol is considered the primary source of the green odor and is also the most important component in tea aroma,significantly affecting the overall aroma.However,the biosynthesis and accumulation of(Z)-3-hexenol during tea processing have not been fully analyzed.In this study,we found that withering treatment at different times and withering plus shaking treatment at different degrees promoted the accumulation of important volatile components of green tea odor,especially(Z)-3-hexenol by GC-MS.The RNA-seq and qRT-PCR results showed that withering and withering plus shaking treatments enhanced the expression of(Z)-3-hexenol-related genes in tea leaves,including synthetic pathway 1 genes(CsLOX3,CsHPL1,CsADH4,and CsAHD1),synthetic pathway 2 genes(CsGLU),and synthetic pathway 3 genes(CsCXEs).Correlation analysis of the key odorants and important genes in the three synthetic pathways revealed that some CsCXEs were positively correlated with green odor compounds.The in vitro enzyme activity results showed that rCsCXE3(GWHTASIV011658),and rCsCXE6(GWHTASIV031480)exhibited hydrolytic activity against three tea acetate compounds[hexyl acetate,(E)-2-hexyl acetate,and(Z)-3-hexyl acetate],resulting in the production of corresponding alcohol compounds.In summary,withering and shaking treatment during tea processing promoted the expression of CsCXE3 and CsCXE6,thereby enhancing the production of hexenol compounds.These compounds play a crucial role in increasing the green odor of tea.
基金supported by Zhejiang Science and Technology Major Program on Agricultural New Variety Breeding-Tea Plant, China (2021C02067-6)the National Key Research and Development Program of China (2021YFD1200200)+1 种基金the Fundamental Research Fund for Tea Research Institute of the Chinese Academy of Agricultural Sciences (1610212022009)the Zhejiang Provincial Natural Science Foundation, China (Z24C160010) to Chunlei Ma。
文摘Anthracnose is a devastating disease caused by Colletotrichum that significantly affects the yield and economic value of the tea plant(Camellia sinensis). However, few studies have addressed the genetic mechanism of anthracnoseresistance(AR). This study investigated the QTL associated with AR in a 'Longjing 43'×'Baijiguan'(LJ43×BJG)population. The field surveys conducted in this study led to the identification of several QTLs for AR on the linkagemap. One major QTL(qAR-12.4) accounted for 12% of the phenotypic variance explained over two years. The BSA-seq results also revealed two genomic regions, q ARChr1 on chromosome 1 and qARChr13 on chromosome 13,which showed strong correlations with AR. Time-course RNA-seq was performed on LJ43 and BJG inoculated withanthracnose at 0, 24, and 48 hours to screen for candidate genes. The results showed the gradual post-inoculationexpression of a nuclear-localized ERF transcription factor(CsERF105) within the qARChr1 locus in BJG but not inLJ43. The AR of BJG was significantly reduced after feeding with CsERF105-specific antisense oligonucleotides,suggesting that CsERF105 may be a positive regulator. The findings of this study add to our general knowledge ofthe genetic factors involved in the tea plant's AR and potential breeding targets.
基金supported by the Special Scientific Research Funds for Commonweal Section of the Ministry of Agriculture, China (nyhyzx07-3-35)the Natural Science Foundation of Zhejiang Province, China (R3090394)the Key Laboratory of Processing and Quality Control of Tea & Beverage Plants Products, Ministry of Agriculture, China (2010K1004)
文摘The relationship between the amount of tea cream and the chemical components contents in the original green tea infusion was investigated. The results showed that the amounts of tea cream in the green tea infusions obtained from different cultivars and different parts of new shoots were varied. There were many chemical components participating in the formation of green tea cream. However, there were only the contents of caffeine （Y=0.85, P〈0.01） and polyphenols （Y=0.65, P〈0.05） in the original green tea infusion highly correlated with the amount of green tea cream. Stepwise regression analysis of overall chemical components indicated that the contents of caffeine and gallated catechins in the original green tea infusion had a significant effect （P〈0.01） on green tea cream levels. Cream （g L-1）=-172.071＋ 0.129×Ccaffeine＋0.024×Ggallated catechins （R2=0.936）. The amount of green tea cream can be predicted by the contents of gallated catechins and caffeine in the original tea infusion. Principal component analysis also indicated that catechins, minerals, and polysaccharides were the important chemical components in the formation of green tea cream.
基金financially supported by the National Key Research and Development Program of China (2018YFC1604402)the Natural Science Foundation of Zhejiang Province, China (LY17C140002)+1 种基金the Fundamental and Public Welfare of Zhejiang Province, China (LGN18C160006)the College Student Innovation and Entrepreneurship of Zhejiang Province, China (2017R409055)
文摘Thirteen volatile compounds were identified from Flemingia macrophylla plants. Eight major components significantly attracted the tea green leafhoppers, Empoasca flavescens F. Based on their relative abundances, following synthetic blends were made for field experiments: 1) eight-component-attractant blend included Z-3-hexen-1-ol, Z-3-hexenyl acetate, Z-ocimene, Me SA, Z-3-hexenyl butyrate, dodecane, hexadecane and nonanal at 10, 10, 1, 11, 2, 6, 2 and 4 mg mL^-1 in n-hexane, respectively;2) four-component-attractant blend #1 contained hexadecane, Z-3-hexenyl acetate, Z-3-hexen-1-ol and nonanal at 2, 10, 10 and 4 mg mL^-1 in n-hexane, respectively;3) four-component-attractant blend #2 contained hexadecane, Z-3-hexenyl acetate, Z-3-hexen-1-ol and Me SA at 2, 10, 10 and 11 mg mL^-1 in n-hexane, respectively. Thymol and 1-methoxy-4-methyl-2-(1-methylethyl)-benzene, identified from Lavandula angustifolia aeration samples, significantly repelled the leafhopper as strong repellents when tested alone or in combination at 10 mg mL^-1. For field bioassays, each attractant lure was attached to a bud green sticky board hung from a bamboo stick at above tea plant level for catching the leafhoppers, whereas the repellent dispenser was tied to a tea branch inside tea clump for pushing the leafhoppers away from tea clumps. The results showed that the eight-component-attractant blend caught similar numbers of the leafhopper as did the four-component-attractant blend #1 at about 53–79 leafhoppers/trap/day, which were significantly higher than those on the hexane-control bud green sticky boards. Average leafhopper catches from un-baited sticky boards were about 51–73 leafhoppers/trap/day when pushed by the repellents placed inside tea plants, with the two-component-repellent blend being more effective than their single components. When the two-component-repellent blend was further tested with the three attractant blends in a push-pull fashion, average trap catches ranged from 62 to 92 leafhoppers/trap/day. Control efficacy on the leafhoppers within the push-pull zones increased progressively from day 1(43%) to day 5(73%). This push-pull approach might have a great potential as a green control strategy for combating the tea green leafhoppers.
基金supported by Hubei Science and Technology Plan Key Project(G2019ABA100)。
文摘Myriad evidence attests to the health-promoting benefits of tea drinking.While there are multiple factors of tea influencing the effective biological properties,tea polyphenols are the most significant and valuable components.The chemical characterization and physical characteristics of tea polyphenols have been comprehensively studied over the previous years.Still the emergence of new chemistry in tea,particularly the property of scavenging reactive carbonyl species(RCS)and the newly discovered flavoalkaloid compounds,has drawn increasing attention.In this review,we summarize recent findings of a new class of compounds in tea-flavonoid alkaloids(flavoalkaloids),which exist in fresh tea leaves and can be generated during the process of post-harvesting,and also postulate the formation mechanism of flavoalkaloids between catechins and theanine-derived Strecker aldehyde.Additionally,we detail the up-to-date research results of tea polyphenols regarding their ability to trap RCS and their in vivo aminated metabolites to suppress advanced glycation ends products(AGEs).We further raise questions to be addressed in the near future,including the synthetic pathways for the generation of flavoalkaloids and AGEs in fresh tea leaves before processing and the concentrations of tea polyphenols that affect their RCS scavenging capability due to their pro-oxidant nature.More intensive research is warranted to elucidate the mechanisms of action underlying the biological activity of flavoalkaloids and the pharmacological application of tea polyphenols in scavenging RCS and impeding detrimental AGEs.
基金supported by the Key Technology R&D Program of Jiangsu Province(BE2020341)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Theasinensin A(TSA),a dimer of epigallocatechin gallate,has been preliminarily demonstrated to have hypoglycemia and anti-inflammatory effects.However,little information is available on its potential mechanisms of anti-diabetes.Therefore,the present study aimed to investigate the influence of TSA on glucose and lipid metabolism and gut microbiota in high-fat-diet/streptozotocin-induced diabetic mice.As result,TSA improved polydipsia,polyphagia and impaired glucose tolerance of diabetic mice,declined the fasting blood glucose and hepatic triglyceride level,and enhanced the expression at mRNA level of insulin receptor substrate,phosphoinositide 3-kinase,protein kinase B and glucagon-like peptide 1 receptor(GLP-1R)in the diabetic liver.Moreover,TSA could restore the disorder of gut microbiota of diabetic mice.High-dose(100 mg/kg)TSA showed better benefi cial effects from the blood biochemical parameters,hepatic function and gut microbiota.In general,high-dose TSA significantly modulated gut microbiota by increasing the relative abundance of Akkermansia and decreasing the relative abundances of Acetatifactor,Anaerotruncus,Pseudofl avonifactor,Oscillibacter and Clostridium clusters.The results indicated that TSA could exert an anti-diabetes effect in diabetic mice through restoring glucose homeostasis,declining hepatic steatosis,activating insulin and GLP-1 signaling pathways,and ameliorating gut microbiota dysbiosis.
基金supported by The National Natural Science Foundation of China(grant number 31871804)Natural Science Foundation Project of Hunan Province,China(grant number 2020JJ4036)the Key R&D Program of Hunan Province(2020NK2030)。
文摘Dark tea(containing Eurotium cristatum)and black tea have hypoglycemic effects.The black brick tea with fungal growth is obtained from black tea by adding E.cristatum,followed by steaming,pressing,fungal growth,and drying.However,the hypoglycemic effects of black brick tea are still unexplored.Here,we used black brick tea with fungal growth and black tea as raw materials to study their hypoglycemic effects in a hyperglycemic mice model.Both these types of black tea could lower the content of blood glucose and increase the content of hepatic glycogen by upregulating the proteins and m RNA expression of phosphatidylinositol-4,5-bisphosphate3-kinase,glycogen synthase,protein kinase B and phosphoinositidedependent protein kinase-1 and downregulating the protein and m RNA expression of glycogen synthase kinase 3β.These regulatory steps were followed by high activities of glutathione peroxidase and superoxide dismutase and low content of malondialdehyde.These teas can promote blood glucose transport and absorption by upregulating the protein and m RNA expression of insulin receptor substrate-1 and glucose transporter-2 and stimulate glycolysis by upregulating the protein and m RNA expression of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 2.Our study suggests that the black brick tea was more effective than the black tea in terms of hypoglycemic.
文摘A bacterial artificial chromosome （BAC） library is an invaluable resource tool to initiate tea plant genomics research, and the preparation of high molecular weight （HMW） genomic DNA is a crucial first step for constructing a BAC Library. In order to construct a BAC library for enhancing tea plant genomics research, a new method for the preparation of tea pant high molecular weight （HMW） genomic DNA must be developed due to young tea plant leaves and shoots are notably rich in both tea polyphenols and tea polysaccharides. In this paper, a modified method for preparing high quality tea plant HMW genomi~ DNA was optimized, and the quality of tea plant genomic DNA was evaluated. The results were as follows： Critical indicators of HMW DNA preparation were the appearance of the smooth nuclei in solution （as opposed to sticky-gummy） before agarose plug solidification, non-dark colored nuclei plugs after lysis with an SDS/proteinase K solution, and the quality and quantity of HMW DNA fragments after restriction enzyme digestion. Importantly, 1% dissolved PVP-40 and 1% un-dissolved PVP-40 during the nuclei extraction steps, in conjunction with the removal of PVP-40 from the plug washing and nuclei lysis steps, were critical for achieving HWM tea plant DNA suitable for BAC library construction. Additionally, a third PFGE fraction selection step to eliminate contaminating small DNA fragments. The modifications provided parameters that may have prevented deleterious interactions from tea polyphenols and tea polysaccharides. The HMW genomic DNA produced by this new modified method has been used to successfully construct a large-insert tea plant BAC library, and thus may be suitable for BAC library construction from other plant species that contain similarly interfering compounds.
