Comprehensive analysis of pigment alterations and associated flavor development in strip and needle green teas.

Strip/needle green teas (SGT/NGT) processed using innovative technologies are in high demand; however, mechanisms behind their color and flavor have not been comprehensively studied. We aimed to reveal the dynamics of major pigmented components (carotenoids, lipids, flavonoids, and Maillard products) and their contributions to the flavor of green teas. The total content of flavonoids in SGT and NGT were 255 ± 4.51 and 201 ± 3.91 mg·g-1, respectively; these values are slightly lower than that in fresh leaves (FLs), resulting in a fresh and sweet aftertaste. In average, carotene content in SGT/NGT (24.8 µg·g-1) was higher than in FL (17.4 µg·g-1), whilst xanthophyll content (603 µg·g-1) decreased to one-half of that in FL (310 µg·g-1). Among the 218 primary metabolites, glutamine, glutamic acid, and arginine were found to accumulate and were dominate contributors for the umami and sweet taste. Notably, more than 96 volatiles were screened and revealed their correlations with carotenoids, lipids, and amino acids. Overall, the synergism between pigments and their non-enzymatic derivates' contribution to GT characterized flavor was illustrated.

Comprehensive investigation on non-volatile and volatile metabolites in four types of green teas obtained from the same tea cultivar of Longjing 43 (Camellia sinensis var. sinensis) using the widely targeted metabolomics.

In this study, we produced roasted, baked, steamed, and sun-dried green tea products using the same batch of fresh tea leaves (FTL) of Longjing 43 (Camellia sinensis var. sinensis), and explored processing effects on the metabolic profiles of four types of green teas (FGTs) using the widely targeted metabolomics. Results showed that 146 differential metabolites including flavonoids, amino acids, lipids, and phenolic acids were screened among 1034 non-volatiles. In addition, nineteen differential metabolites were screened among 79 volatiles. Most of non-volatiles and volatiles metabolites changed notably in different manufacturing processes, whereas there were no significant differences (p＞0.05) in the levels of total catechins between FGTs and FTL. The transformation of metabolites was the dominant trend during green tea processing. The results contribute to a better understanding of how the manufacturing process influences green tea quality, and provide useful information for the enrichment of tea biochemistry theory.

Aromatic profiles and enantiomeric distributions of chiral odorants in baked green teas with different picking tenderness.

Suitable picking tenderness is an essential prerequisite for manufacturing tea. However, the influence of picking tenderness of fresh tea leaves on the aromatic components is still unclear. In this study, aromatic profiles and chiral odorants in fresh tea leaves and corresponding baked green teas with five levels of tenderness of two representative cultivars were analysed using stir bar sorptive extraction-gas chromatography-mass spectrometry. cis-Linalool oxide (furanoid) and methyl salicylate exhibited significantly increasing trends as samples of all series matured. The content of most chiral odorants was significantly high in the mature samples, and significant content variations of all enantiomers during baked green tea processing could be observed with different trends according to their precursors. In particular, the enantiomeric ratios of most chiral odorants were less influenced by the picking tenderness and processing, while drying (limonene), spreading and fixation (α-terpineol), and spreading (dihydroactinidiolide) influenced the chiral distribution of the aforementioned odorants.

Insights into crucial odourants dominating the characteristic flavour of citrus-white teas prepared from citrus reticulata Blanco 'Chachiensis' and Camellia sinensis 'Fudingdabai'.

Citrus-white teas (CWs), which possess a balanced flavour of tea and citrus, are becoming more popular worldwide; however, their characteristic flavour and odourants received limited research. Volatile components of two types of CWs prepared from Citrus reticulata Blanco 'Chachiensis' and Camellia sinensis 'Fudingdabai' were comprehensively investigated using a combination of stir bar sorptive extraction and gas chromatography-mass spectrometry (GC-MS). Ninety-nine crucial odourants in the CWs were quantified by applying GC-olfactometry/MS, significant differences were compared, and their odour activity values (OAVs) were calculated. Twenty-two odourants (in total 2628.09 and 1131.18 mg/kg respectively) were further confirmed as traditional CW (CW-A) and innovated CW (CW-B) characteristic flavour crucial contributors which all possessed > 1 OAVs, particularly limonene (72919 in CW-A) and trans-ß-ionone (138953 in CW-B). The unravelling of CWs aroma composition will greatly expanding our understanding of tea aroma chemistry and the potential aroma interactions will offer insights into tea blending technologies.

Hypolipidaemic and antioxidant effects of various Chinese dark tea extracts obtained from the same raw material and their main chemical components.

In order to investigate the hypolipidaemic and antioxidant effects of various dark teas produced from different post-fermentation using the same raw material, a hyperlipidaemia zebrafish model combined with binding bile salts assay and antioxidant assays were performed in this study. Results showed that the hypolipidaemic effect of dark tea extracts increased significantly (p < 0.05) while the antioxidant ability decreased sharply compared with raw material. Particularly, Liupao tea (50%) and Pu-erh tea (48%) showed promising hypolipidaemic potential; however, the antioxidant capacity of Pu-erh tea decreased (31-49%) most dramatically. Besides, the levels of total polyphenols and catechins decreased sharply, but theabrownin, gallic acid, and caffeine increased significantly after post-fermentation. Moreover, the potential mechanisms of regulating hyperlipidaemia by dark tea extracts were discussed. These results suggest that microbial fermentation significantly affects the bioactivity of dark teas, and provide theoretical basis for processing and improving of dark tea products for hyperlipidaemia therapy.

Assessment of the contribution of chiral odorants to aroma property of baked green teas using an efficient sequential stir bar sorptive extraction approach.

Chiral volatile compounds are known to be distributed in teas at various enantiomeric ratios. However, the performance of each enantiomer, including aroma characteristics, aroma intensities, and contribution to the overall flavor of tea, is still unclear. In this study, aroma characteristics and intensities of 38 volatile enantiomers in standards and baked green teas with chestnut-like aroma and clean aroma were evaluated by an efficient sequential headspace-stir bar sorptive extraction (seq-HS-SBSE) approach combined with the enantioselective gas chromatography-olfactometry/mass spectrometry (Es-GC-O/MS) technique. Moreover, aroma recombination results for the two types of baked green teas using 14 chiral odorants and four achiral odorants indicated that the combinations of the detected odorants mainly contributed to the "floral", "sweet", and "chestnut-like" aromas. R-Linalool simultaneously enhanced the "floral", "sweet", and "chestnut-like" aromas; R-limonene mainly contributed to the "sweet" and "clean" aromas; and S-α-terpineol promoted the "sweet" and "floral" aromas of baked green tea.

Insight into the pigmented anthocyanins and the major potential co-pigmented flavonoids in purple-coloured leaf teas.

Tea cultivars possessing purple shoots have attracted global interest. In order to gain a better understanding of the major chemical constituents responsible for the purple colouration, we applied widely targeted metabolomics to investigate the pigmented flavonoids of freeze-dried purple-coloured tea leaves (PTLs) in comparison with green-coloured tea leaves (GTLs). Thirty-three anthocyanins were identified, and delphinidin 3-O-galactoside and cyanidin 3-O-galactoside were found to be the most abundant in PTLs. A total of 226 metabolites including 193 flavonoids and 33 tannins were identified, and the methylated, acylated, and glycosylated flavonoids differed significantly between PTLs and GTLs. Moreover, significant differences (p < 0.01) in the average anthocyanin, flavonoid, chlorophyll and catechin contents were also observed. Four PTLs were found to contain high levels of (-)-epigallocatechin-3-(3″-O-methyl) gallate (>10 mg/g). These results suggest that structurally modified anthocyanins and major potential co-pigmented flavonoids are the chemicals primarily responsible for the purple colouration of the tea leaves.

Impact of Various Microbial-Fermented Methods on the Chemical Profile of Dark Tea Using a Single Raw Tea Material.

In the present study, we produced Pu-erh, Liubao, Qingzhuan, and Fuzhuan teas using a single raw tea material and applied widely targeted metabolomics to study the impact of various microbial-fermented methods on the chemical profile of dark tea. The contents of catechins and free amino acids decreased drastically, whereas the contents of gallic acid and theabrownins increased significantly during microbial fermentation. Pu-erh tea had the highest content of theabrownins (11.82 ± 0.49%). Moreover, MS-based metabolomics analysis revealed that the different types of dark teas were significantly different from their raw material. A total of 85 differential metabolites were screened among 569 metabolites identified referring to self-compiled database. Glycosylated, hydroxylated, methylated, and condensed and oxidated products originating from microbial bioconversion of their corresponding primitive forms were significantly increased in dark teas. These results suggest that various microbial-fermented methods greatly affect the metabolic profile of dark tea, which can provide useful information for dark tea biochemistry research.

Discrimination and Identification of Aroma Profiles and Characterized Odorants in Citrus Blend Black Tea with Different Citrus Species.

Citrus blend black teas are popular worldwide, due to its unique flavor and remarkable health benefits. However, the aroma characteristics, aroma profiles and key odorants of it remain to be distinguished and cognized. In this study, the aroma profiles of 12 representative samples with three different cultivars including citrus (Citrus reticulata), bergamot (Citrus bergamia), and lemon (Citrus limon) were determined by a novel approach combined head space-solid phase microextraction (HS-SPME) with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-TOFMS). A total of 348 volatile compounds, among which comprised esters (60), alkenes (55), aldehydes (45), ketones (45), alcohols (37), aromatic hydrocarbons (20), and some others were ultimately identified. The further partial least squares discrimination analysis (PLS-DA) certified obvious differences existed among the three groups with a screening result of 30 significant differential key volatile compounds. A total of 61 aroma-active compounds that mostly presented green, fresh, fruity, and sweet odors were determined in three groups with gas chromatography-olfactometry/mass spectrometry (GC-O/MS) assisted analysis. Heptanal, limonene, linalool, and trans-ß-ionone were considered the fundamental odorants associated with the flavors of these teas. Comprehensive analysis showed that limonene, ethyl octanoate, copaene, ethyl butyrate (citrus), benzyl acetate, nerol (bergamot) and furfural (lemon) were determined as the characterized odorants for each type.

Identification and quantification of key odorants in the world's four most famous black teas.

Keemun, Assam, Darjeeling and Ceylon black teas are honored as the world's four most famous black teas, and their excellent aroma qualities are well received by people around the world. In this study, aroma components in these four types of teas were analyzed by comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOFMS) and gas chromatography-olfactometry (GC-O) technologies. A total of 42 aroma-active compounds were ultimately identified, especially benzeneacetaldehyde, geraniol, (Z)-3-hexen-1-yl hexanoate, trans-ß-ionone, cis-linalool oxide (pyranoid), hotrienol, and methyl salicylate presented the strongest aroma strengths with pleasant scents in all tested teas. The quantification results indicated that 19 compounds including (Z)-3-hexenol, 1-octen-3-ol, linalool, phenylethyl alcohol, hexanal, benzeneacetaldehyde, limonene, heptanoic acid, (Z)-3-hexen-1-ol, acetate, benzyl alcohol, trans-linalool oxide (furanoid), hotrienol, 1-octen-3-one, 2-nonanone, (E)-2-octenal, nonanal, ß-myrcene, 2-pentylfuran, and methylpyrazine were identified as the key compounds with odor activity values (OAVs) higher than 1.0 in the world's four most famous black teas. Notably, the comparison of GC-O and OAV calculation results showed that methyl salicylate (Ceylon), (E)-2-octenal (Assam), benzeneacetaldehyde (Keemun) and linalool and trans-linalool oxide (furanoid) (Darjeeling) might be the most definitive odorants in the corresponding tea categories.

Variation patterns in the content of glycosides during green tea manufacturing by a modification-specific metabolomics approach: Enzymatic reaction promoting an increase in the glycosidically bound volatiles at the pan firing stage.

The glycosides are presumed to influence the quality of green tea but the molecular mechanism behind remains unclear. To elucidate the contribution of glycosides to the flavor formation of green tea, changes of both glycosidically bound non-volatiles (GBNVs) and glycosidically bound volatiles (GBVs) during the manufacturing of green tea were investigated using a modification-specific metabolomics method. A total of 64 glycosides (47 GBNVs and 17 GBVs) were identified and their contents mainly changed during the pan firing and drying stages of green tea manufacturing. Notably, the contents of GBVs significantly increased by 1.12-4.46-fold during pan firing. Correlation analysis showed that the GBVs contents were negatively related to the contents of volatiles and glucose. Model experiments revealed that enzymatic synthesis contributed to the increase in the content of GBVs during the pan firing. This comprehensive study on the glycosides changes revealed the molecular bases for GBVs increments during the pan firing.

The enantiomeric distributions of volatile constituents in different tea cultivars.

Although the enantiomeric distribution of chiral volatiles presents great potential in discrimination of tea cultivars and their geographic origins, this area has received little attention. Thus, we herein aimed to determine the relationships between tea cultivars and the enantiomeric distributions of their chiral volatile constituents. Headspace solid-phase microextraction (HS-SPME) and enantioselective gas chromatography-mass spectrometry (Es-GC-MS) were employed to quantify 15 volatile components in 22 tea cultivars from different locations within China. The tea cultivars were successfully differentiated by their geographical origins, and the concentrations of R-linalool, S-citronellol, S-E-nerolidol, (1R, 2R)-methyl jasmonate, S-α-ionone, and the two enantiomers of linalool oxide A differed significantly among the different groups. It should also be noted that tea processing methods greatly influenced the formation of volatile enantiomers. Our results demonstrated that the enantiomeric distribution of volatile constituents closely correlates with the geographical origins, leaf types, and manufacturing suitabilities of the tea cultivars examined herein.

Metabolomics Investigation Reveals That 8-C N-Ethyl-2-pyrrolidinone-Substituted Flavan-3-ols Are Potential Marker Compounds of Stored White Teas.

White teas of different stored ages have varied flavor, bioactivity, and commercial value. In this study, a liquid chromatography-mass spectrometry-based metabolomics investigation revealed that there are distinct differences among the compound patterns of Baihaoyinzhen (BHYZ) and Baimudan (BMD) white teas with various storage durations. The levels of flavan-3-ols, procyanidins, theasinensins, theaflavins, flavonol- O-glycosides, flavone- C-glycosides, and most of the amino acids were reduced after long-term (>4 years) storage. More importantly, 8-C N-ethyl-2-pyrrolidinone-substituted flavan-3-ols (EPSFs), including seven novel compounds discovered in white teas for the first time, were formed from theanine and flavan-3-ols during storage, and their contents were positively correlated with the storage duration. These findings were further confirmed by the linearly increasing formation of EPSFs in reaction solution and BMD white teas stored in an environment-controlled cabinet. In conclusion, EPSFs were detected in white teas for the first time and were discovered as marker compounds and potential indicators for long-term storage of white tea.

Identification of key odorants responsible for chestnut-like aroma quality of green teas.

A chestnut-like aroma is widely considered an important indicator of an excellent-quality green tea; however, the key odorants responsible for chestnut-like aroma have never been systematically studied and remain unknown. In this study, the aroma components of green teas and Chinese chestnuts were analyzed using comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-TOFMS), and 58 compounds were identified as common aroma components among green teas, boiled Chinese chestnuts, roasted Chinese chestnuts and raw Chinese chestnuts. Subsequently, 17 volatiles, including 3-methylbutanal, (E)-3-penten-2-one, ethylbenzene, heptanal, benzaldehyde, 2-pentylfuran, octanal, benzeneacetaldehyde, (E)-2-octenal, (E,E)-3,5-octadien-2-one, linalool, nonanal, (E)-2-nonenal, decanal, (Z)-hex-3-en-1-yl hexanoate, trans-ß-ionone and (E)-nerolidol, were identified as the key odorants responsible for chestnut-like aroma based on the odor activity value (OAV) calculation method. Besides, the comparison of OAVs of key odorants between fresh tea leaves and finished teas indicated that all key odorants were present in fresh tea leaves and that their contents increased or decreased during tea processing. Moreover, the comparison between results of OAV and gas chromatography-olfactometry (GC-O) methods showed that ethylbenzene, heptanal, benzaldehyde, 2-pentylfuran, (E,E)-3,5-octadien-2-one, linalool, (Z)-hex-3-en-1-yl hexanoate and trans-ß-ionone were the common identified compounds between the two methods. The identification of chestnut-like aroma in green teas will provide a theoretical basis for further research on the directional adjustment and control of tea aroma quality.

Application of metabolomics profiling in the analysis of metabolites and taste quality in different subtypes of white tea.

Three subtypes of white tea, Silver Needle (SN), White Peony (WP), and Shou Mei (SM), differ in their taste, aroma, bioactivity, and commercial value. Here, a metabolomics investigation on the chemical compositions combining taste equivalent-quantification and dose-over-threshold (DoT) determination on the taste qualities were applied to comprehensively characterize the white tea subtypes for the first time. Significant differences in the contents of catechins, dimeric catechins, amino acids, phenolic acids, flavonol/flavone glycosides, and aroma precursors were observed among these 3 white teas. Metabolite content comparison and partial least-squares (PLS) analysis suggest that theanine, aspartic acid, asparagine, and AMP were positively correlated with the umami taste in white tea, and flavan-3-ols, theasinensins, procyanidin B3, and theobromine had positive correlations with higher bitterness and astringency tastes. In addition, puckering astringent (-)-epigallocatechin gallate (EGCG), (-)-epicatechin gallate (ECG) and theogallin, bitter-tasting caffeine, and the mouth-drying/velvety-like astringent γ-aminobutyric acid (GABA) were identified as key taste compounds of white tea infusion by absolute quantification and DoT factor calculations. This work provided systematic and comprehensive knowledge on the chemical components, taste qualities, and sensory active metabolites for the subtypes of white tea.

Metabolomic analysis reveals the composition differences in 13 Chinese tea cultivars of different manufacturing suitabilities.

BACKGROUND: Green tea and black tea are manufactured using appropriate tea cultivars in China. However, the metabolite differences relating to the manufacturing suitability of tea cultivars are unclear. In the present study, we performed a non-targeted metabolomic analysis on 13 Chinese tea cultivars using ultra-high performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry to investigate comprehensively the metabolite differences between cultivars suitable for manufacturing green tea (GT cultivars) and cultivars suitable for manufacturing both green tea and black tea (G&BT cultivars). RESULTS: Multivariate statistical analysis and cluster analysis divided the 13 cultivars into two groups, namely GT cultivars and G&BT cultivars, which correlated with their manufacturing suitability. The GT cultivars contained higher levels of flavonoid glycosides, whereas the G&BT cultivars contained higher levels of catechins, dimeric catechins, phenolic acids and alkaloids. CONCLUSION: Metabolic pathway analysis revealed that the flavonoid pathway inclined toward the synthesis of flavonoid glycosides in GT cultivars, whereas it inclined toward the synthesis of catechins and phenolic acids in G&BT cultivars. The results of the present study will be helpful for discriminating the manufacturing suitability of tea cultivars and investigating their breeding. © 2017 Society of Chemical Industry.

Characterization of white tea metabolome: Comparison against green and black tea by a nontargeted metabolomics approach.

White tea is considered the least processed form of tea and is reported to have a series of potent bioactivities, such as antioxidant, anti-inflammatory, anti-mutagenic, and anti-cancer activities. However, the chemical composition of white tea and the dynamic changes of the metabolites during the manufacturing process are far from clear. In this study, we applied a nontargeted metabolomics approach based on ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF/MS) to comprehensively profile the characteristic metabolites of white tea. There were significant differences in the content of amino acids, catechins, dimeric catechins, flavonol and flavone glycosides, and aroma precursors in white tea compared with green and black teas that were manufactured from the same fresh tea leaves. Furthermore, the dynamic changes of the metabolites in the tea samples with various withering durations of 0, 4, 8, 12, 16, 20, 24, 28, and 36 h were also profiled. This study offers a comprehensive characterization of the metabolites and their changes in white tea.

Enantiomeric and quantitative analysis of volatile terpenoids in different teas (Camellia sinensis).

Volatile terpenoids play important roles in the formation of tea aroma quality due to their pleasant scents and low odor thresholds. Most volatile terpenoids contain stereogenic centers, which results in various stereo distributions of their enantiomers and diastereoisomers in different types of tea. However, the distribution characteristics of terpenoid enantiomers in teas were still unclear, which poses an obstacle to the scientific understanding of tea aroma. In this work, a new and efficient analysis approach based on headspace solid phase microextraction (HS-SPME)-chiral gas chromatography-mass spectrometry (GC-MS) was established to analyze 12 pairs of familiar terpenoid enantiomers in different teas. The extraction efficiency of the HS-SPME method to extract volatile terpenoids in teas was the greatest when using CAR-DVB-PDMS (50/30µm) fibers and 1:10 proportions between tea and boiling water at a 50°C extraction temperature for 40min, and the stability observation of enantiomeric ratios of the terpenoids well proved the feasibility of the extraction method. The favorable limits of detection, limits of quantitation, repeatability, linearity, and concentration ranges of each terpenoid enantiomer demonstrated the repeatability and reliability of the analytical approach. The enantiomeric and quantitative analyses indicated that S-limonene, S-linalool, (2S, 5S)-linalool oxide A, (2S, 5R)-linalool oxide B, R-4-terpineol, (2S, 5R)-linalool oxide C, (2S, 5S)-linalool oxide D, S-α-terpineol, R-α-ionone, peak 1 of theaspirane A and peak 2 of theaspirane B were the major terpenoid components in most Chinese teas; instead, higher proportions of the opposite enantiomers of the above terpenoids were frequently detected in black teas with large leaf origin and Indonesia white teas. Besides, great diversities of enantiomeric ratios and concentrations among different teas were observed. Furthermore, partial least-squares discriminant analyses were performed to distinguish the concentration differences of the terpenoid enantiomers among different teas; the analysis results indicated that highly significant concentration differences existed between large and small leaf origins of black teas, and significant differences of the concentrations of linalool oxides A-C were observed between green, white and dark teas. The successful application of this chiral analysis technique of tea aroma will lay a scientific foundation for further quality assessment, botanical origin determination and authenticity assessment of teas.

Nontargeted Modification-Specific Metabolomics Investigation of Glycosylated Secondary Metabolites in Tea (Camellia sinensis L.) Based on Liquid Chromatography-High-Resolution Mass Spectrometry.

Glycosylation on small molecular metabolites modulates a series of biological events in plants. However, a large number of glycosides have not been discovered and investigated using -omics approaches. Here, a general strategy named "nontargeted modification-specific metabolomics" was applied to map the glycosylation of metabolites. The key aspect of this method is to adopt in-source collision-induced dissociation to dissociate the glycosylated metabolite, causing a characteristic neutral loss pattern, which acts as an indicator for the glycosylation identification. In an exemplary application in green teas, 120 glucosylated/galactosylated, 38 rhamnosylated, 21 rutinosylated, and 23 primeverosylated metabolites were detected simultaneously. Among them, 61 glycosylated metabolites were putatively identified according to current tea metabolite databases. Thanks to the annotations of glycosyl moieties in advance, the method aids metabolite identifications. An additional 40 novel glycosylated metabolites were tentatively elucidated. This work provides a feasible strategy to discover and identify novel glycosylated metabolites in plants.

Transcriptional responses and flavor volatiles biosynthesis in methyl jasmonate-treated tea leaves.

BACKGROUND: Tea (Camellia sinensis) has long been consumed worldwide for its amazing flavor and aroma. Methyl jasmonate (MeJA), which acts as an effective elicitor among the plant kingdom, could mostly improve the quality of tea aroma by promoting flavor volatiles in tea leaves. Although a variety of volatile secondary metabolites that contribute to aroma quality have been identified, our understanding of the biosynthetic pathways of these compounds has remained largely incomplete. Therefore, information aboaut the transcriptome of tea leaves and, specifically, details of any changes in gene expression in response to MeJA, is required for a better understanding of the biological mechanisms of MeJA-mediated volatiles biosynthesis. Moreover, MeJA treatment could exaggerate the responses of secondary metabolites and some gene expression which offer a better chance to figure out the mechanism. RESULTS: The results of two-dimensional gas-chromatograph mass-spectrometry showed that the terpenoids content in MeJA-treated tea leaves increased, especially linalool, geraniol, and phenylethyl alcohol. More importantly, we carried out RNA-seq to identify the differentially expressed genes (DEGs) related to volatiles biosynthesis pathways induced by MeJA treatment (0 h, 12 h, 24 h and 48 h) in tea leaves. We identified 19245, 18614, 11890 DEGs respectively in the MeJA_12h, MeJA_24 h and MeJA_48 h samples. The α-Lenolenic acid degradation pathway was firstly responded resulting in activating the JA-pathway inner tea leaves, and the MEP/DOXP pathway significantly exaggerated. Notably, the expression level of jasmonate O-methyltransferase, which is associated with the central JA biosynthesis pathway, was increased by 7.52-fold in MeJA_24 h tea leaves. Moreover, the genes related to the terpenoid backbone biosynthesis pathway showed different expression patterns compared with the untreated leaves. The expression levels of 1-deoxy-D-xylulose-phosphate synthase (DXS), all-trans-nonaprenyl-diphosphate synthase, geranylgeranyl reductase, geranylgeranyl diphosphate synthase (type II), hydroxymethylglutaryl-CoA reductase and 4-hydroxy-3-methylbut-2-enyl diphosphate reductase increased by approximately 2-4-fold. CONCLUSIONS: The results of two-dimension gas-chromatography mass-spectrometry analysis suggested that exogenous application of MeJA could induce the levels of volatile components in tea leaves, especially the geraniol, linalool and its oxides. Moreover, the transcriptome analysis showed increased expression of genes in α-Lenolenic acid degradation pathway which produced massive jasmonic acid and quickly activated holistic JA-pathway inner tea leaves, also the terpenoid backbones biosynthesis pathway was significantly affected after MeJA treatment. In general, MeJA could greatly activate secondary metabolism pathways, especially volatiles. The results will deeply increase our understanding of the volatile metabolites biosynthesis pathways of tea leaves in response to MeJA.