Understanding Darjeeling tea flavour on a molecular basis

Gohain, Bornali; Borchetia, Sangeeta; Bhorali, Priyadarshini; Agarwal, Niraj; Bhuyan, Lakshi Prasad; Rahman, Azizur; Sakata, Kanzo; Mizutani, Masaharu; Shimizu, Bun-ichi; Gurusubramaniam, G.; Ravindranath, R.; Kalita, Mohan Chandra; Hazarika, Manjil; Das, Sudripta

doi:10.1007/s11103-012-9887-0

Cited by 50 publications

(16 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1B). Transcriptomic analysis revealed that enhanced flavour (aroma) due to altered expression levels of the genes in the corresponding pathways occurs in some tea cultivars or results from insect infestation of fresh leaves (Gohain et al, 2012).…”

Section: Introductionmentioning

confidence: 99%

Green tea flavour determinants and their changes over manufacturing processes

et al. 2016

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

Green tea flavour determinants and their changes over manufacturing processes

et al. 2016

View full text Add to dashboard Cite

“…Loivamäki et al (2004) also reported that jasmonate induction led to an increase in tobacco alkaloids, phenolics, and diterpene glycosides in Nicotiana attenuate. Moreover, the impacts of MeJA on the biosynthesis of volatile compounds in climacteric and non-climacteric fruits, such as apples and strawberries, respectively, have also been reported (Ayala-Zavala et al, 2005;Kim et al, 2006;de la Peña Moreno et al, 2010a;2010b;Belhadj et al, 2008;Gohain et al, 2012). However, investigations toward the effects of exogenous MeJA on tea aroma have been scarcely reported.…”

Section: Introductionmentioning

confidence: 99%

Aroma changes of black tea prepared from methyl jasmonate treated tea plants

Shi

Wang²,

et al. 2014

J. Zhejiang Univ. Sci. B

View full text Add to dashboard Cite

Methyl jasmonate (MeJA) was widely applied in promoting food quality. Aroma is one of the key indicators in judging the quality of tea. This study examined the effect of exogenous MeJA treatment on tea aroma. The aroma components in black tea prepared from MeJA-treated fresh tea leaves were extracted using headspace solid-phase microextraction (HS-SPME) and were analyzed using gas chromatography-mass spectrometry (GC-MS) and GC-olfactometry (GC-O). Forty-five volatile compounds were identified. The results revealed that the MeJA-treated black tea had higher levels of terpene alcohols and hexenyl esters than the untreated tea. Moreover, several newly components, including copaene, cubenol, and indole, were induced by the MeJA treatment. The activities of polyphenol oxidase and β-glucosidase in fresh tea leaves changed after the MeJA treatment. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis indicated that the gene expression levels of polyphenol oxidase and β-primeverosidase were upregulated by two and three folds, respectively, by the MeJA treatment (P<0.01); however, the gene expression of β-glucosidase was downregulated to a half level. In general, the aroma quality of the MeJAtreated black tea was clearly improved.

show abstract

“…In this study, the raw Cp values of all the reference genes are transformed into relative quantities using ΔΔCt method [25]. For relative quantification assays, the expression of the target gene is expressed as ratio of target-to-reference gene in the same sample.…”

Section: Relative Gene Expression (Qrt-pcr) Analysis Of the Enzymes Imentioning

confidence: 99%

A Proteomic Approach to Evaluate the Effects of Endogenous Expression of Cryptogein Gene in Crypt-Transgenic Plants of Bacopa monnieri

Paul

Nandagopal

Agarwala

et al. 2017

JABB

View full text Add to dashboard Cite

Cryptogein, a 10 kDa sterol scavenging protein secreted by the oomycete Phytophthora cryptogea [1], belongs to 'elicitin' class of elicitors [2]. Cryptogein has been used to study the underlying molecular mechanisms of disease resistance in tobacco. Application of purified cryptogein protein, even in nanomolar quantity causes hypersensitive response (HR)-like necrosis in tobacco plants [3] and also induces systemic acquired resistance (SAR) to P. parasitica var nicotianae [4].There are several reports on transformation with cryptogein (crypt) gene aimed to achieve the resistance against plant pathogens. Over expression of β-cryptogein induces HR in tobacco and triggers resistance against P. parasitica var nicotianae [5,6] and other pathogens. Effective increase in biomass and/ or secondary metabolites accumulation in crypt-transgenic cultures in a number of plant species have also been observed [7][8][9], where the crypt gene was either under the constitutive promoter [7] or under the inducible promoter [8]. AbstractCryptogein, a proteinaceous elicitor has been reported to affect growth and secondary metabolism in several plant species. We established two transgenic plant lines of Bacopa monnieri L., an indigenous medicinal species, following Agrobacterium tumefaciens mediated transformation. The transgenic plant lines obtained following transformation with strains LBA4404-nptII-crypt (plant line BmAt-ncrypt) and LBA4404-nptII (plant line BmAt-n), were maintained on selection media i.e. MS medium containing 100 mg/l Kanamycin. To evaluate the effects of endogenous expression of cryptogein gene in crypt-transgenic plants of B. monnieri, in the present study, a proteomic approach was employed. Using 2D-PAGE followed by MALDI TOF MS/MS, we found 54 spots with reproducible differences in abundance (≥ +2 or ≤ -0.5-fold) between the plant lines. Bioinformatics analyses helped their identification, functional annotation and categorization.Significantly upregulated gene expression (p≤ 0.5) of most of the key enzymes of triterpenoid saponin biosynthetic pathway (mevalonate kinase, mvk; mevalonate diphosphate decarboxylase, mdc; squalene synthase, sqs; β-amyrin synthase, bas and UDP-glycosyl transferase 2, ugt 2) in crypt-transgenic plant lines (BmAt-ncrypt) of B. Monnieri was observed as compared to non-transformed (Bm-NT) and empty vector control (BmAt-n) plant lines. Cryptogein-induced ROS production, a typical stress response of plant cells towards cryptogein, was significantly increased (p≤ 0.5) in specific activities and higher abundance of several anti-oxidant enzymes, such as SOD (3.0-5.0-fold), APX (2.3-3.0-fold) and CAT (2.6-fold) in BmAt-ncrypt. The upregulation of CaM (1.6-fold) and calcium-transporting ATPase-2 (2.0-fold) in BmAt-ncrypt indicate possible calcium-dependant cryptogein elicitation. A 3.0-fold increase in EIN3 levels with down-regulation of F-box protein, its regulator also indicate induction of JA-ET signalling pathway in crypt-transgenic plants. This study not only demonstrates involvement of ...

show abstract

Understanding Darjeeling tea flavour on a molecular basis

Cited by 50 publications

References 36 publications

Green tea flavour determinants and their changes over manufacturing processes

Green tea flavour determinants and their changes over manufacturing processes

Aroma changes of black tea prepared from methyl jasmonate treated tea plants

A Proteomic Approach to Evaluate the Effects of Endogenous Expression of Cryptogein Gene in Crypt-Transgenic Plants of Bacopa monnieri

Contact Info

Product

Resources

About