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Plant Mol Biol ; 106(6): 533-554, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34263437


KEY MESSAGE: The role of central carbon metabolism in the synthesis and emission of scent volatiles in tuberose flowers was revealed through measurement of changes in transcripts and metabolites levels. Tuberose or Agave amica (Medikus) Thiede & Govaerts is a widely cultivated ornamental plant in several subtropical countries. Little is known about metabolite networking involved in biosynthesis of specialized metabolites utilizing primary metabolites. In this study, metabolite profiling and gene expression analyses were carried out from six stages of maturation throughout floral lifespan. Multivariate analysis indicated distinction between early and late maturation stages. Further, the roles of sugars viz. sucrose, glucose and fructose in synthesis, glycosylation and emission of floral scent volatiles were studied. Transcript levels of an ABC G family transporter (picked up from the floral transcriptome) was in synchronization with terpene volatiles emission during the anthesis stage. A diversion from phenylpropanoid/benzenoid to flavonoid metabolism was observed as flowers mature. Further, it was suggested that this metabolic shift could be mediated by isoforms of 4-Coumarate-CoA ligase along with Myb308 transcription factor. Maximum glycosylation of floral scent volatiles was shown to occur at the late mature stage when emission declined, facilitating both storage and export from the floral tissues. Thus, this study provides an insight into floral scent volatiles synthesis, storage and emission by measuring changes at transcripts and metabolites levels in tuberose throughout floral lifespan.

Agave/genética , Flores/genética , Regulação da Expressão Gênica de Plantas , Odorantes/análise , Transcriptoma , Compostos Orgânicos Voláteis/metabolismo , Agave/crescimento & desenvolvimento , Agave/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Flores/crescimento & desenvolvimento , Flores/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Perfilação da Expressão Gênica/métodos , Hidroxibenzoatos/análise , RNA-Seq/métodos
Phytochemistry ; 162: 10-20, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30844491


Polianthes tuberosa L. (tuberose) is a widely cultivated ornamental crop in Asian countries. Different cultivars of tuberose have been developed through breeding programs in India. However, no reports on floral fragrance and metabolite contents of these cultivars are available. In this study, an attempt has been made to evaluate the levels of both volatile and non-volatile metabolites from seven different cultivars of P. tuberosa. Presence of benzenoids, phenylpropanoids, terpenoids, and few fatty acid derivatives as emitted, endogenous and glycosylated forms were revealed from the studied cultivars. Further, chemometric analyses in both supervised and unsupervised manner led to identification of patterns among the cultivars. Among the seven cultivars, four distinct clusters were obtained linking to their volatiles, flavonoids and primary metabolite levels. Metabolic variations obtained from the cultivars also suggest cross-talks between phenylpropanoid, benzenoid, and flavonoid pathways. Thus metabolite profiling reported here may help in characterization of tuberose cultivars for perfumery utility and future breeding programme.

Asparagaceae/metabolismo , Flores/metabolismo , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Biotecnologia
Nat Prod Res ; 33(3): 435-438, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29553803


Emitted scent volatile profile of an orchid species Zygopetalum maculatum was studied using dynamic headspace sampling technique with four different adsorbent matrices, namely Porapak Type Q polymer (mesh size: 80/100), Tenax (mesh size: 60/80), activated charcoal and graphite. In addition, developmental variations in scent emissions and endogenous volatile levels were also investigated. Gas chromatography-mass spectrometry analysis revealed the presence of 21 volatile compounds in the headspace, which was predominantly enriched with benzenoid compounds. Among these benzenoids, o-diethylbenzene and p-diethylbenzene were the major compounds followed by benzyl acetate and methyl salicylate. Among the phenylpropanoid compounds, 2-phenylethyl acetate was the major volatile. However, as compared to benzenoids, the quantity was much lesser, indicating the inclination of phenylalanine flux towards benzenoid pathway. The outcome of this study has the implications in enhancing fragrance and vase life of orchids of the Sikkim Himalaya region and thus may further help to meet the growing market demand.

Odorantes/análise , Orchidaceae/química , Compostos Orgânicos Voláteis/isolamento & purificação , Adsorção , Derivados de Benzeno/análise , Derivados de Benzeno/química , Derivados de Benzeno/isolamento & purificação , Carvão Vegetal , Flores/química , Cromatografia Gasosa-Espectrometria de Massas , Siquim , Compostos Orgânicos Voláteis/química
Appl Microbiol Biotechnol ; 102(17): 7389-7406, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29934653


Quorum sensing, the microbial communication system, is gaining importance as a therapeutic target against pathogens. The two key reasons for the rising demand of quorum sensing (QS) inhibitory molecules are low selective pressure to develop resistance by pathogens and possibility of more species-specific effects. Due to complex interactions in a unique niche of live plant tissues, endophytes, as a survival mechanism, potentially produce various bioactive compounds such as QS inhibitors. We report the isolation of an endophytic fungus Kwoniella sp. PY016 from the medicinal plant "Bahera" (Terminalia bellirica), which exhibits substantial quorum sensing inhibition and anti-biofilm activities against the standard test organism, Chromobacterium violaceum. Sugar, sugar alcohol, carboxylic acid, lipid, and phenolic classes of metabolites (predominantly xylitol) are responsible components of the metabolome for the desired bioactivity. A judicious combination of single-factor-at-a-time strategy and artificial neural network modeling combined with genetic algorithm was employed for the selection and optimization of the critical process and medium parameters. Through this newly adopted hybrid model-based optimization, the quorum sensing inhibitory activity of the endophytic metabolome was increased by ~ 30%. This is the first report on optimization of QS inhibitory activity from any fungal endophyte using such a hybrid advanced approach.

Antibacterianos/farmacologia , Basidiomycota/metabolismo , Endófitos/metabolismo , Metaboloma , Modelos Teóricos , Percepção de Quorum/efeitos dos fármacos , Algoritmos , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Chromobacterium/efeitos dos fármacos , Redes Neurais de Computação , Plantas Medicinais/microbiologia , Terminalia/microbiologia