Regeneração e cultura in vitro de espécies de Passiflora

O gênero Passiflora compõe centenas de espécies, a maioria de origem dos trópicos e das florestas da América do Sul, as quais são agrupadas em 21 subgêneros. Algumas espécies foram intensamente estudadas por sua importância econômica e são cultivadas principalmente para a produção de suco de fruta. Cultura de 29 espécies de Passiflora foram obtidos a partir de embriões zigóticos e de culturas de endosperma. Foram obtidos diferentes tipos de calos de crescimento, de tal forma que plantas foram regeneradas a partir de calos de 13 espécies diferentes. Não haviam sido ainda relatadas culturas in vitro para 25 das espécies trabalhadas.The genus Passiflora comprises hundred species, mainly native of the South American tropics and rainforests, which are grouped into 21 subgenera. Some species are widely studied for their economic importance and are chiefly cultivated for production of fruit juice. To obtain a continuous source of material for a screening of secondary metabolites, zygotic embryo culture was attempted for 62 Passiflora species, starting from seeds mainly collected in the wild. Twenty nine of these species produced calli, which had very different growth rates. Plants were successfully regenerated from calli of 13 different species. For 25 of the responsive species this is the first report of in vitro culture

In vitro culture from mature seeds of Passiflora species

The genus Passiflora comprises hundred species, mainly native of the South American tropics and rainforests, which are grouped into 21 subgenera. Some species are widely studied for their economic importance and are chiefly cultivated for production of fruit juice. To obtain a continuous source of material for a screening of secondary metabolites, zygotic embryo culture was attempted for 62 Passiflora species, starting from seeds mainly collected in the wild. Twenty nine of these species produced calli, which had very different growth rates. Plants were successfully regenerated from calli of 13 different species. For 25 of the responsive species this is the first report of in vitro culture

Metabolomic Profiling and Antioxidant Activity of Fruits Representing Diverse Apple and Pear Cultivars

The false fruits of apple (Malus domestica) and pear (Pyrus communis) are consumed all over the world, contributing to the dietary intake of health-promoting antioxidant phytochemicals. For example, polyphenols confer many beneficial effects (according to their chemical structure, bioavailability, and absorption efficiency in the gut) and the consumption of polyphenol-rich apple and pear fruits may therefore reduce the risk of some diseases. However, the content of such molecules is highly dependent on the specific fruit cultivar. To examine this metabolic diversity in detail, we used metabolomic analysis (NMR and HPLC-DAD/MS) to profile the metabolome of six apple and five pear cultivars. We also determined the antioxidant capacity of the extracts (FRAP assay) and correlated this with the metabolomic composition and abundance of specific metabolites. We observed the cultivar-specific accumulation of sugars, amino acids, malic acid, and various polyphenols, which was also related to the growing season for some cultivars. We found that the ancient Italian apple Pom Prussian was enriched for chlorogenic acid as well as more characteristic polyphenols (phloretin derivatives), the pear cultivar Abate Fetel was low in sucrose, and both cultivars displayed high in vitro antioxidant activity. These cultivars may, therefore, be particularly attractive to health-conscious consumers

The Terroir Concept Interpreted through Grape Berry Metabolomics and Transcriptomics

Terroir refers to the combination of environmental factors that affect the characteristics of crops such as grapevine (Vitis vinifera) according to particular habitats and management practices. This article shows how certain terroir signatures can be detected in the berry metabolome and transcriptome of the grapevine cultivar Corvina using multivariate statistical analysis. The method first requires an appropriate sampling plan. In this case study, a specific clone of the Corvina cultivar was selected to minimize genetic differences, and samples were collected from seven vineyards representing three different macro-zones during three different growing seasons. An untargeted LC-MS metabolomics approach is recommended due to its high sensitivity, accompanied by efficient data processing using MZmine software and a metabolite identification strategy based on fragmentation tree analysis. Comprehensive transcriptome analysis can be achieved using microarrays containing probes covering ~99% of all predicted grapevine genes, allowing the simultaneous analysis of all differentially expressed genes in the context of different terroirs. Finally, multivariate data analysis based on projection methods can be used to overcome the strong vintage-specific effect, allowing the metabolomics and transcriptomics data to be integrated and analyzed in detail to identify informative correlations

Towards a scientific interpretation of the terroir concept: plasticity of the grape berry metabolome

BACKGROUND: The definition of the terroir concept is one of the most debated issues in oenology and viticulture. The dynamic interaction among diverse factors including the environment, the grapevine plant and the imposed viticultural techniques means that the wine produced in a given terroir is unique. However, there is an increasing interest to define and quantify the contribution of individual factors to a specific terroir objectively. Here, we characterized the metabolome and transcriptome of berries from a single clone of the Corvina variety cultivated in seven different vineyards, located in three macrozones, over a 3-year trial period. RESULTS: To overcome the anticipated strong vintage effect, we developed statistical tools that allowed us to identify distinct terroir signatures in the metabolic composition of berries from each macrozone, and from different vineyards within each macrozone. We also identified non-volatile and volatile components of the metabolome which are more plastic and therefore respond differently to terroir diversity. We observed some relationships between the plasticity of the metabolome and transcriptome, allowing a multifaceted scientific interpretation of the terroir concept. CONCLUSIONS: Our experiments with a single Corvina clone in different vineyards have revealed the existence of a clear terroir-specific effect on the transcriptome and metabolome which persists over several vintages and allows each vineyard to be characterized by the unique profile of specific metabolites.Andrea Anesi, Matteo Stocchero, Silvia Dal Santo, Mauro Commisso, Sara Zenoni, Stefania Ceoldo, Giovanni Battista Tornielli, Tracey E. Siebert, Markus Herderich, Mario Pezzotti and Flavia Guzz

Produzione di molecole bioattive da colture in vitro di cellule vegetali

Le colture in vitro di cellule vegetali sono potenzialmente utilizzabili per produrre una vasta gamma di molecole di interesse industriale, tra cui prodotti o intermedi del metabolismo secondario. Possibili vantaggi delle colture in vitro, rispetto alle colture in campo o in serra, consistono nella possibilità di produrre una grande quantità di biomassa indipendentemente dalle variazioni ambientali e nella semplificazione dei cosiddetti “down stream processes” (estrazione, purificazione ecc.). Settori industriali potenzialmente interessati a questo tipo di produzione sono il settore farmaceutico (ad esempio per la produzione di antitumorali, antiossidanti, antibatterici, antiinfiammatori), il settore alimentare (es. fungicidi e antibatterici, additivi naturali quali aromi e coloranti), il settore agrario (es. pesticidi), il settore cosmetico (es. profumi). Il nostro gruppo si sta occupando delle potenziali molecole di interesse applicativo prodotte da colture di Daucus carota e di Passiflora ssp

Carrot specific features of the phenylpropanoid pathway identified by feeding cultured cells with defined intermediates

Plants produce a vast array of secondary metabolites, many of which have important biological propertiesin animals when consumed as part of the diet. Interestingly, although the activities and benefits of plantsecondary metabolites in animals are well established, comparatively little is known about the endogenousfunctions of these compounds in plants. One way to investigate the role of secondary products inplants is to modify the secondary metabolome and investigate the impact of such modifications on thephenotype.We have designed a novel feeding approach using different hydroxycinnamic acids (HCAs) and thecyanidin precursor dihydroquercetin (DHQ) to modify the metabolome of carrot R3M suspension cells.This strategy increased the accumulation of specific metabolites in a predictable way, and providednovel insights into the carrot phenylpropanoid pathway, suggesting that (a) cells use HCA hexose estersas substrates in the biosynthetic pathway leading to the accumulation of the various HCA derivativesand (b) pcoumaricacid derivative levels play a key roles in the regulation the flux of HCAs along thepathway.Moreover, this rapid strategy for metabolome modification does not depend on the availability ofmolecular tools or knowledge and can therefore be applied to any plant species

Approcci per lo studio del ruolo biologico di specifici metaboliti secondari.

La relazione tra la struttura e le diverse propriet\ue0 fisico-chimiche delle antocianine, quali l'assorbimento della luce, la stabilit\ue0, la reattivit\ue0, \ue8 stata ampiamente studiata. A parte l'ovvio ruolo vesperale nei fiori e nei frutti, l'attivit\ue0 antiossidanti esercitata anche in vivo e il loro ruolo nell'assorbimento dell'eccesso di luce e nella protezione dell'apparato fotosintetico, le informazioni sul ruolo specifico di specifiche antocianine nelle cellule che le producono ed accumulano sono scarse. Per investigare su questo aspetto, si \ue8 ideata una strategia sperimentale che consiste nel variare il profilo metabolico di colture cellulari nel valutare l'effetto della variazione metabolica sulla capacit\ue0 delle cellule di rispondere ad uno stress di tipo abiotico. Le colture cellulari utilizzate (di Ocimum basilicum, Petunia hybrida e Daucus carota), sono state selezionate per la produzione di antocianine e accumulano anche alti livelli di acidi idrossicinnamici, presentando un loro caratteristico profilo metabolico riguardo a queste due classi di metaboliti secondari. La variazione del profilo metabolico viene ottenuta mediante somministrazione di inibitori enzimatici e o precursori della via metabolica dei fenilpropanoidi. Gli stress abbi ottici utilizzati finora consistono in uno stress ossidativo, ottenuto attraverso somministrazione di glucosio e glucosio ossidasi, che generano acqua ossigenata e uno stress termico (1h a 44\ub0C). l\u2019effetto di tali stress e sulle colture cellulari viene valutato mediante analisi al microscopio e analisi di metaboliti attraverso HPLC-DAD e HPLC-ESI-MS. in cultura cellulare di basilico il trattamento con acido 3,4-metilenediossi-cinnamico, inibitore della formazione di coumaroyl-CoA,porta ad una riduzione del contenuto di alcune antocianine, acido rosmarino e altri derivati di acidi idrossicinnamici. Linee cellulari di pecunia che producono antocianine derivate dalla delfinidina, petunidina e malvidina, in seguito a trattamento con acido piperonilico (che inibisce la formazione di acido cumarico), subiscono una diminuzione nell\u2019accumulo di tali metaboliti, mentre la contemporanea somministrazione di taxifolina, precursore della cianidina, promuove la formazione di nuovi derivati della cianidina e della peonidina. Dati preliminari indicano che in presenza di acido piperonilico lo stress ossidativo causa un aumento della mortalit\ue0 cellulare rispetto il controllo. Colture cellulari di carota pigmentate R3M sono caratterizzate da antocianine derivate dalla cianidina e acilate con diversi acidi idrossicinnamici. In seguito alla somministrazione di taxifolina e di specifici acidi idrossicinnamici, \ue8 stato possibile incrementare l\u2019accumulo delle rispettive antocianine acilate, ad eccezione delle antocianine acilate con acido caffeico. Per valutare l\u2019effetto di queste modificazioni del profilo metabolico sulla resistenza allo stress si \ue8 utilizzato lo stress termico, che causa gravi danni alle cellule di carota, attivando un processo di morte lenta preceduta dall\u2019aggregazione del citoplasma in placche, oltre a un danno ossidativo alle membrane cellulari. Tra i vari trattamenti analizzati, si \ue8 visto che la somministrazione di taxifolina e acido ferulico (che porta alla diminuzione della maggior parte dei metaboliti, all\u2019accumulo della cianidina acilata con acido ferulico e alla comparsa dei diversi nuovi derivati dell\u2019acido ferulico) favorisce una maggiore resistenza ai danni provocati dallo stress termico e alla conseguente morte cellulare