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Introduction and objectives: Since the use of a bio stimulant should provide a response to a problem that depends on the production system implemented (crops, plant model, soil, climate, the farmer's practices...), the agricultural sector is facing concomitant challenges of choosing the best bio stimulant that suits their needs. Thus, understanding bio stimulant-plant interactions, at molecular level, using metabolomics approaches is a prerequisite, for the development of a bio stimulant, leading to an effective exploration and application of formulations in agriculture. AGRO-K®, is commercialized as a plant-based bio stimulant that improve vigor and enhance resistance to lodging in cereal crops. A recent previous untargeted metabolomics study has demonstrated the ability of this bio stimulant to improve wheat resistance to lodging, in real open-field conditions. However, the reproducibility of the impact of this bio stimulant in other filed crops is not yet investigated. Methods: Therefore, the present study aimed to assess the changes in primary and secondary metabolites in the roots, stems, and leaves of fiber flax (Linum usitatissimum L), treated with the bio stimulant, using NMR and LC-MS-based untargeted metabolomics approach. Results and conclusions: In addition to the previous result conducted in wheat, the present analysis seemed to show that this bio stimulant led to a similar pathway enhancement in flax. The pathways which seem to be reproducibly impacted are hydroxycinnamic acid amides (HCAAs), phenylpropanoids and flavonoids. Impacting these pathways enhance root growth and elongation and cell wall lignification, which can aid in preventing crop lodging. These results confirm that HCAAs, flavonoids, and phenylpropanoids could serve as signatory biomarkers of the impact of AGRO-K® on improving lodging resistance across various plant species. [ABSTRACT FROM AUTHOR]

The antioxidant action of terngymnoside C (1) and hydroxytyrosol-1-glucoside (2), isolated for the first time from the flower buds of Ternstroemia lineata, as well as katsumadin (3), obtained from the seedless fruits, was evaluated using ABTS•+ and H2O2–Saccharomyces cerevisiae models. In silico docking analysis of 1, 2, and 3 determined their affinity forces to the aquaporin monomers of the modeled S. cerevisiae protein 3 (AQP3) and human protein 7 (AQP7) channels that regulate the H2O2 cell transport. The ABTS•+ antiradical capacity of these compounds showed IC50 values of 22.00 μM (1), 47.64 μM (2), and 73.93 μM (3). The S. cerevisiae antioxidant assay showed that at 25 µM (1) and 50 µM (2 and 3), the cells were protected from H2O2-oxidative stress. These compounds, together with quercetin and vitamin C, were explored through the modeled S. cerevisiae AQP3 and human AQP7 by molecular docking analysis. To explain these results, an antioxidant mechanism for the isolated compounds was proposed through blocking H2O2 passage mediated by aquaporin transport. On the other hand, 1, 2, and 3 were not cytotoxic in a panel of three cancer cell lines. [ABSTRACT FROM AUTHOR]

Introduction: The cacao tree (Theobroma cacao), a perennial crop that serves as a source of cacao beans, can suffer from drastic climate changes such as irregular rainfall and shorter rainy seasons. The search for hybrids which are capable of producing specific metabolites favoring adaptation in new climatic conditions is a challenge in cacao farming. Objectives: We aimed to (1) analyze the metabolic changes in calli of three cacao genotypes during water deficit induced by incubation with polyethylene glycol and (2) assess their response to water deficit stress with regard to somatic embryo differentiation. Methods: Metabolic profiling was carried out using 1H‐NMR spectroscopy and multivariate data analysis was applied to crude extracts of calli grown in non‐stress or water deficit stress conditions. Results: Water deficit stress influences the capacity of calli to produce embryos. The SCA12 genotype exhibited the best conversion capacity under severe conditions and was considered as tolerant to drought, followed by the SCA6 genotype (mid‐tolerant) and the MA12 genotype (sensitive). Fifty‐four metabolites were identified in the three cacao genotypes and discriminant metabolites were identified. Metabolites involved in water stress tolerance such as fructose, trans‐aconitic acid, leucine, and hydroxybenzene derivatives were observed in SCA12, the tolerant genotype. Conclusion: These results demonstrate the utility of 1H‐NMR metabolomics as an essential tool for the analysis of the drought tolerance characteristics of T. cacao. This study mapped the metabolome variation in three genotypes of cacao callus during water deficit induced with polyethylene glycol using 1H‐NMR spectroscopy and multivariate data analysis. The SCA12 genotype was considered as tolerant to drought, followed by the SCA6 (mid‐tolerant) and the MA12 (sensitive). Fifty‐four metabolites were identified in the three cacao genotypes and discriminant metabolites were identified. Metabolites involved in water stress tolerance such as fructose, trans‐aconitic acid, leucine, and hydroxybenzene derivatives were observed in SCA12, the tolerant genotype. [ABSTRACT FROM AUTHOR]

Introduction: Bio stimulants are substances and/or microorganisms that are used to improve plant growth and crop yields by modulating physiological processes and metabolism of plants. While research has primarily focused on the broad effects of bio stimulants in crops, understanding their cellular and molecular influences in plants, using metabolomic analysis, could elucidate their effectiveness and offer possibilities for fine-tuning their application. One such bio stimulant containing galacturonic acid as elicitor is used in agriculture to improve wheat vigor and strengthen resistance to lodging. Objective: However, whether a metabolic response is evolved by plants treated with this bio stimulant and the manner in which the latter might regulate plant metabolism have not been studied. Method: Therefore, the present study used 1H-NMR and LC–MS to assess changes in primary and secondary metabolites in the roots, stems, and leaves of wheat (Triticum aestivum) treated with the bio stimulant. Orthogonal partial least squares discriminant analysis effectively distinguished between treated and control samples, confirming a metabolic response to treatment in the roots, stems, and leaves of wheat. Results: Fold-change analysis indicated that treatment with the bio stimulation solution appeared to increase the levels of hydroxycinnamic acid amides, lignin, and flavonoid metabolism in different plant parts, potentially promoting root growth, implantation, and developmental cell wall maturation and lignification. Conclusion: These results demonstrate how non-targeted metabolomic approaches can be utilized to investigate and monitor the effects of new agroecological solutions based on systemic responses. [ABSTRACT FROM AUTHOR]

Tillandsia species are plants from the Bromeliaceae family which display biomonitoring capacities in both active and passive modes. The bioaccumulation potential of Tillandsia aeranthos (Loisiel.) Desf. and Tillandsia bergeri Mez acclimated to Southern/Mediterranean Europe has never been studied. More generally, few studies have detailed the maximum accumulation potential of Tillandsia leaves through controlled experiments. The aim of this study is to evaluate the maximum accumulation values of seven metals (Co, Cu, Mn, Ni, Pb, Pt, and Zn) in T. aeranthos and T. bergeri leaves. Plants were immersed in different mono elemental metallic solutions of Co (II), Cu (II), Mn (II), Ni (II), Pb (II), Pt (IV), and Zn (II) ions at different concentrations. In addition, cocktail solutions of these seven metals at different concentrations were prepared to study the main differences and the potential selectivity between metals. After exposure, the content of these metals in the leaves were measured by inductively coupled plasma-optical emission spectrometry. Data sets were evaluated by a fitted regression hyperbola model and principal component analysis, maximum metal loading capacity, and thermodynamic affinity constant were determined. The results showed important differences between the two species, with T. bergeri demonstrating higher capacity and affinity for metals than T. aeranthos. Furthermore, between the seven metals, Pb and Ni showed higher enrichment factors (EF). T. bergeri might be a better bioaccumulator than T. aeranthos with marked selectivity for Pb and Ni, metals of concern in air quality biomonitoring. [ABSTRACT FROM AUTHOR]

Background: The extraction of thylakoids is an essential step in studying the structure of photosynthetic complexes and several other aspects of the photosynthetic process in plants. Conventional protocols have been developed for selected land plants grown in controlled conditions. Plants accumulate defensive chemical compounds such as polyphenols to cope with environmental stresses. When the polyphenol levels are high, their oxidation and cross-linking properties prevent thylakoid extraction. Results: In this study, we developed a method to counteract the hindering effects of polyphenols by modifying the grinding buffer with the addition of both vitamin C (VitC) and polyethylene glycol (PEG4000). This protocol was first applied to the marine plant Posidonia oceanica and then extended to other plants synthesizing substantial amounts of polyphenols, such as Quercus pubescens (oak) and Vitis vinifera (grapevine). Native gel analysis showed that photosynthetic complexes (PSII, PSI, and LHCII) can be extracted from purified membranes and fractionated comparably to those extracted from the model plant Arabidopsis thaliana. Moreover, total protein extraction from frozen P. oceanica leaves was also efficiently carried out using a denaturing buffer containing PEG and VitC. Conclusions: Our work shows that the use of PEG and VitC significantly improves the isolation of native thylakoids, native photosynthetic complexes, and total proteins from plants containing high amounts of polyphenols and thus enables studies on photosynthesis in various plant species grown in natural conditions. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) with a large chemical diversity are emitted by plant flowers. These compounds play an important role in the ecology of plants. This review presents the different ecological roles of VOCs present in the odor plumes of plant flowers, such as pollination, defense, adaptation to their environment, and communication with other organisms. The production and accumulation sites of VOCs in plants with their spatial and temporal variations, including environmental issues, are also summarized. To evaluate the qualitative and quantitative chemical composition of VOCs, several methods of extraction and analysis were used. Headspace (HS) sampling coupled with solid phase microextraction (SPME) is now well-developed for the extraction process. Parameters are known, and several fibers are now available to optimize this extraction. Most of the time, SPME is coupled with gas chromatography-mass spectrometry (GC-MS) to determine the structural identification of the VOCs, paying attention to the use of several complementary methods for identification like the use of databases, retention indices, and, when available, comparison with authentic standards analyses. The development of the knowledge on VOCs emitted by flowers is of great importance for plant ecology in the context of environmental and climate changes. [ABSTRACT FROM AUTHOR]

The search for potent antimicrobial compounds is critical in the face of growing antibiotic resistance. This study explores Acalypha arvensis Poepp. (A. arvensis), a Caribbean plant traditionally used for disease treatment. The dried plant powder was subjected to successive extractions using different solvents: hexane (F1), dichloromethane (F2), methanol (F3), a 50:50 mixture of methanol and water (F4), and water (F5). Additionally, a parallel extraction was conducted using a 50:50 mixture of methanol and chloroform (F6). All the fractions were evaluated for their antimicrobial activity, and the F6 fraction was characterized using untargeted metabolomics using SPME-GC×GC-TOFMS. The extracts of A. arvensis F3, F4, and F5 showed antibacterial activity against Staphylococcus aureus ATCC 25923 (5 mg/mL), MRSA BA22038 (5 mg/mL), and Pseudomonas aeruginosa ATCC 27853 (10 mg/mL), and fraction F6 showed antibacterial activity against Staphylococcus aureus ATCC 29213 (2 mg/mL), Escherichia coli ATCC 25922 (20 mg/mL), Pseudomonas aeruginosa ATCC 27853 (10 mg/mL), Enterococcus faecalis ATCC 29212 (10 mg/mL), Staphylococcus aureus 024 (2 mg/mL), and Staphylococcus aureus 003 (2 mg/mL). Metabolomic analysis of F6 revealed 2861 peaks with 58 identified compounds through SPME and 3654 peaks with 29 identified compounds through derivatization. The compounds included methyl ester fatty acids, ethyl ester fatty acids, terpenes, ketones, sugars, amino acids, and fatty acids. This study represents the first exploration of A. arvensis metabolomics and its antimicrobial potential, providing valuable insights for plant classification, phytochemical research, and drug discovery. [ABSTRACT FROM AUTHOR]

Fusarium oxysporum is the one of the most common and impactful pathogens of flax. Cultivars of flax that show resistance to this pathogen have previously been identified. To better understand the mechanisms that are responsible for this resistance, we conducted time-lapse analysis of one susceptible and one resistant cultivar over a two-week period following infection. We also monitored changes in some metabolites. The susceptible cultivar showed a strong onset of symptoms from 6 to 8 days after inoculation, which at this time point, was associated with changes in metabolites in both cultivars. The resistant cultivar maintained its height and normal photosynthetic capacity but showed a reduced growth of its secondary stems. This resistance was correlated with the containment of the pathogen at the root level, and an increase in some metabolites related to the phenylpropanoid pathway. [ABSTRACT FROM AUTHOR]

The aim of this study was to identify the chemical composition and sequential structure of alginate isolated from C. crinita harvested in the Bulgarian Black Sea, as well as its effects in histamine-induced paw inflammation in rats. The serum levels of TNF-α, IL-1β, IL-6, and IL-10 in rats with systemic inflammation, and the levels of TNF-α in a model of acute peritonitis in rats were also investigated. The structural characterization of the polysaccharide was obtained by FTIR, SEC-MALS, and 1H NMR. The extracted alginate had an M/G ratio of 1.018, a molecular weight of 7.31 × 104 g/mol, and a polydispersity index of 1.38. C. crinita alginate in doses of 25 and 100 mg/kg showed well-defined anti-inflammatory activity in the model of paw edema. A significant decrease in serum levels of IL-1β was observed only in animals treated with C. crinita alginate in a dose of 25 mg/kg bw. The concentrations of TNF-α and IL-6 in serum were significantly reduced in rats treated with both doses of the polysaccharide, but no statistical significance was observed in the levels of the anti-inflammatory cytokine IL-10. A single dose of alginate did not significantly alter the levels of the pro-inflammatory cytokine TNF-α in the peritoneal fluid of rats with a model of peritonitis. [ABSTRACT FROM AUTHOR]

VOCs emitted by flowers play an important role in plant ecology. In the past few years, the Tillandsia genus has been scarcely studied according to the VOCs emitted by flowers. Hence, we decided to enlarge the VOCs composition study already undergone in our laboratory on fragrant 3 Tillandsia species to 12 unscented and 2 faint-scented Tillandsia species and hybrids. The headspace solid phase microextraction (HS-SPME) coupled with gas chromatography combined with the mass spectrometry (GC-MS) method was used to explore the chemical diversity of the VOCs. This study allowed the identification of 65 VOCs among the 14 species and between 6 to 25 compounds were identified in each of the species. The aromatic profile of 10 of the species and hybrids are similar to each other's and show 8 predominant compounds: benzaldehyde, benzacetaldehyde, hexanol, hexanal, heptanal, octanal, nonanal, and furan-2-pentyl. Some specific compounds are present only in some unique species such as trans-calamenene, α-muurolene, and α-guaiene trans-β-bergamotene. The two faint-scented species studied present an original aromatic profile with a high number of monoterpenes or phenylpropanoids/benzenoids. Our studies allow a better understanding of the ecological role and function of these VOCs in the interactions between these plants with their environment. [ABSTRACT FROM AUTHOR]

Erismadelphus exsul Mildbr bark is widely used in Gabonese folk medicine. However, little is known about the active compounds associated with its biological activities. In the present study, phytochemical profiling of the ethanolic extract of Erismadelphus exsul was performed using a de-replication strategy by coupling HPLC-ESI-Q/TOF with a molecular network approach. Eight families of natural compounds were putatively identified, including cyclopeptide alkaloids, esterified amino acids, isoflavonoid- and flavonoid-type polyphenols, glycerophospholipids, steroids and their derivatives, and quinoline alkaloids. All these compounds were identified for the first time in this plant. The use of molecular networking obtained a detailed phytochemical overview of this species. Furthermore, antioxidant (2,2-diphenyl-1-picryl-hydrazylhydrate (DPPH) and ferric reducing capacity (FRAP)) and in vitro antimicrobial activities were assessed. The crude extract, as well as fractions obtained from Erismadelphus exsul, showed a better reactivity to FRAP than DPPH. The fractions were two to four times more antioxidant than ascorbic acid while reacting to FRAP, and there was two to nine times less antioxidant than this reference while reacting to DPPH. In addition, several fractions and the crude extract exhibited a significant anti-oomycete activity towards the Solanaceae phytopathogen Phytophthora infestans in vitro, and, at a lower extent, the antifungal activity against the wheat pathogen Zymoseptoria tritici had growth inhibition rates ranging from 0 to 100%, depending on the tested concentration. This study provides new insights into the phytochemical characterization and the bioactivities of ethanolic extract from Erismadelphus exsul bark. [ABSTRACT FROM AUTHOR]

In vitro culture of flax (Linum usitatissimum L.) was exposed to chitosan oligosaccharides (COS) in order to investigate the effects on the growth and secondary metabolites content in roots and shoots. COS are fragments of chitosan released from the fungal cell wall during plant–pathogen interactions. They can be perceived by the plant as pathogen-associated signals, mediating local and systemic innate immune responses. In the present study, we report a novel COS oligosaccharide fraction with a degree of polymerization (DP) range of 2–10, which was produced from fungal chitosan by a thermal degradation method and purified by an alcohol-precipitation process. COS was dissolved in hydroponic medium at two different concentrations (250 and 500 mg/L) and applied to the roots of growing flax seedlings. Our observations indicated that the growth of roots and shoots decreased markedly in COS-treated flax seedlings compared to the control. In addition, the results of a metabolomics analysis showed that COS treatment induced the accumulation of (neo)lignans locally at roots, flavones luteolin C-glycosides, and chlorogenic acid in systemic responses in the shoots of flax seedlings. These phenolic compounds have been previously reported to exhibit a strong antioxidant and antimicrobial activities. COS oligosaccharides, under the conditions applied in this study (high dose treatment with a much longer exposure time), can be used to indirectly trigger metabolic response modifications in planta, especially secondary metabolism, because during fungal pathogen attack, COS oligosaccharides are among the signals exchanged between the pathogen and host plant. [ABSTRACT FROM AUTHOR]

Summary: Cell wall localized heterogeneous polyesters are widespread in land plants. The composition of these polyesters, such as cutin, suberin, or more plant‐specific forms such as the flax seed coat lignan macromolecule, can be determined after total hydrolysis of the ester linkages. The main bottleneck in the structural characterization of these macromolecules, however, resides in the determination of the higher order monomer sequences. Partial hydrolysates of the polyesters release a complex mixture of fragments of different lengths, each present in low abundance and therefore are challenging to structurally characterize. Here, a method is presented by which liquid chromatography–mass spectrometry (LC‐MS) profiles of such partial hydrolysates are searched for pairs of related fragments. LC‐MS peaks that show a mass difference corresponding to the addition of one or more macromolecule monomers were connected in a network. Starting from the lowest molecular weight peaks in the network, the annotation of the connections as the addition of one or more polyester monomers allows the prediction of consecutive and increasingly complex adjacent peaks. Multi‐stage MS (MSn) experiments further helped to reject, corroborate, and sometimes refine the structures predicted by the network. As a proof of concept, this procedure was applied to partial hydrolysates of the flax seed coat lignan macromolecule, and allowed to characterize 120 distinct oligo‐esters, consisting of up to six monomers, and containing monomers and linkages for which incorporation in the lignan macromolecule had not been described before. These results showed the capacity of the approach to advance the structural elucidation of complex plant polyesters. Significance Statement: Most analyses of plant polyesters have focussed on hydrolysates to determine their composition. Partial hydrolysates release a mixture of oligo‐esters that are too low abundant for purification, hampering any advance in the elucidation of the macromolecular structure. We developed an liquid chromatography–mass spectrometry‐based strategy for the structural characterization of a large number of oligo‐esters in partial hydrolysates. Application to the flax lignan macromolecule shows the relevance of the method in advancing the structural characterization of plant polyesters. [ABSTRACT FROM AUTHOR]

In eudicotyledons, accumulation of trihydroxycinnamoyl spermidine that is restricted to the pollen wall constitutes an evolutionary conserved trait. However, the role of this compound, which is synthetized by the BAHD enzyme spermidine hydroxycinnamoyl transferase (SHT), is still a matter of debate. Here, we show that this particular phenolamide is replaced by tetrahydroxycinnamoyl spermine in the pollen coat of the Asteraceae. Phylogenetic analyses combined with quantitative RT-PCR experiments allowed the identification of two homologous genes from Cichorium intybus (chicory) putatively involved in its metabolism. In vitro biochemical characterization of the two enzymes, named CiSHT1 and CiSHT2, confirmed the capability of recombinant proteins to synthesize spermine as well as spermidine derivatives. The wild-type metabolic phenotype was partially restored in an Arabidopsis sht mutant expressing CiSHT2. Strikingly, the transgenic plants also accumulated spermine derivatives that were absent in the wild-type. Overexpression of CiSHT2 in chicory hairy roots led to the accumulation of spermine derivatives, confirming its in vivo function. Complementary sequence analyses revealed the presence of an amino acid motif typical of the SHTs among the BAHD enzyme family. Our results highlight a recent neofunctionalization among the SHTs that has promoted the emergence of new phenolamides in the Asteraceae, which could potentially have contributed to the evolutionary success of this family. [ABSTRACT FROM AUTHOR]

Secoisolariciresinol (SECO) is a natural antioxidant lignan accumulated in large amounts in the seedcoat of flax and retained in the flaxseed cake residue during linseed oil pressing. Here SECO was extracted and purified from flaxseed cake and assayed for its ability to prevent oxidation of linseed oil and an o/w emulsion containing linseed oil. For this purpose, an accelerated storage (Schaal oven) test was performed and SECO effectiveness was compared to that of two antioxidants commonly used in food and cosmetic products: α-tocopherol (α-TOCO) and butylated hydroxyanisole (BHA). In our hands, SECO addition, ranging from 50 to 500 μmole per kg oil, significantly decreased the production of both primary (conjugated dienes, CD) and secondary (thiobarbituric acid-reactive substances, TBARS) oxidation products. This study evidenced that SECO is an effective stabilizer of linseed oil and its o/w emulsion and this protective effect outperformed both the natural α-TOCO and the synthetic BHA antioxidants. In particular, SECO was the most effective in the protection of the o/w emulsion against secondary oxidation products, which makes it a potential alternative preservative for oily products in foods and cosmetics. Practical applications: The present study could lead to applications in the food and cosmetic industries for the stabilization of o/w emulsions. Addition of SECO to linseed oil, already rich in ω-3, could also result in a new functional food with synergistic beneficial actions on human health. Secoisolariciresinol, a natural antioxidant lignan accumulated in large amounts in the seedcoat of flax is here presented as an effective protectant of both bulk oil and o/w emulsion against secondary oxidation products, which makes it a potential alternative preservative for oily products in foods and cosmetics. [ABSTRACT FROM AUTHOR]

The brown alga Stypocaulon scoparium, collected from the Mediterranean coast of Algeria in the Bejaia region, was chosen as a model to study its alginate. This polysaccharide was extracted and characterized by HPAEC-PAD, SEC-MALLS, H-NMR spectroscopy and FT-IR. The ratio of D-mannuronate to L-guluronate (M/G ratio) in the alginate was 0.92 in FTIR spectra at bands of 815 and 900 cm for mannuronic acid (ManA) and guluronic acid (GulA), respectively, which was comparable to alginate of other brown algae, and 0.73 with H-NMR spectroscopy. Complete acid hydrolysis of alginate using the HPAEC technique showed the composition of the two main acid sugars as GulA (G) and ManA (M) with an M/G ratio of 0.6, and 50 % yield. The Mw value for S. scoparium was 2.236 × 105 g mol, and polydispersity index Ip = Mw/Mn =1.714 ± 0.039, which was similar to that of other brown alga samples identified and cited. Partial acid hydrolysis of the alginate gave three fractions, which were characterized. Thus, the alginate sample from S. scoparium was very rich in guluronic block (G-blocks) structures (43.53 %). The guluronic blocks were degraded with poly-guluronate lyase from Flavobacterium multivorum to oligoguluronate via a β-elimination reaction, with Mw = 3.742 × 10 g mol. [ABSTRACT FROM AUTHOR]

Introduction Abiotic stress is a major cause of yield loss in plant culture. Miscanthus, a perennial C4 grass, is now considered a major source of renewable energy, especially for biofuel production. During the first year of planting in Northern Europe, Miscanthus was exposed to frost temperature, which generated high mortality in young plants and large loss of yield. One strategy to avoid such loss is to apply cold-acclimation, which confers on plants a better resistance to low temperature. Objectives The aim of this study is to describe the effect of a cold-acclimation period on the metabolome of two Miscanthus genotypes that vary in their frost sensitivity at the juvenile stage. Miscanthus × giganteus (GIG) is particularly sensitive to frost, whereas Miscanthus sinensis August Feder (AUG) is tolerant. Materials and methods Polar metabolite extraction was performed on Miscanthus, grown in non-acclimated or cold-acclimated conditions. Extracts were analysed by 1H-NMR followed by multivariate statistical analysis. Discriminant metabolites were identified. Results More than 40 metabolites were identified in the two Miscanthus genotypes. GIG and AUG showed a different metabolic background before cold treatment, probably related to their genetic background. After cold-acclimation, GIG and AUG metabolomes remained different. The tolerant genotype showed notably higher levels of accumulation in proline, sucrose and maltose when subjected to cold. Conclusion These two genotypes seem to have a different adaptation strategy in cold conditions. The studied change in the metabolome concerns different types of molecules related to the cold-tolerant behaviour of Miscanthus. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Industrial chicory has been the subject of numerous studies, most of which provide clinical observations on its health effects. Whether it is the roasted root, the flour obtained from the roots or the different classes of molecules that enter into the composition of this plant, understanding the molecular mechanisms of action on the human organism remains incomplete. In this study, we were interested in three molecules or classes of molecules present in chicory root: fructose, chlorogenic acids, and sesquiterpene lactones. We conducted experiments on the murine model and performed a nutrigenomic analysis, a metabolic hormone assay and a gut microbiota analysis, associated with in vitro observations for different responses. We have highlighted a large number of effects of all these classes of molecules that suggest a pro-apoptotic activity, an anti-inflammatory, antimicrobial, antioxidant, hypolipidemic and hypoglycemic effect and also an important role in appetite regulation. A significant prebiotic activity was also identified. Fructose seems to be the most involved in these activities, contributing to approximately 83% of recorded responses, but the other classes of tested molecules have shown a specific role for these different effects, with an estimated contribution of 23–24%. [ABSTRACT FROM AUTHOR]

Introduction - Hydroponics has been shown as a possible way to produce high quality plant biomass with improved phytochemical levels. Nevertheless, effects of plant biotic and abiotic environment can lead to drastic changes and plant growth conditions must be optimised. Objective - To evaluate how much microbes and Agrobacterium rhizogenes TR7 wild strain may affect the tropane alkaloid profile in Datura innoxia Mill. plants cultivated in hydroponic conditions. Methodology - Datura innoxia Mill. plants were cultivated in hydroponic with sterile or non-sterile conditions. For half of the non-sterile plants, Agrobacterium rhizogenes TR7 strain was added to the nutrient solution for hydroponics. The tropane alkaloid content of leaves and roots was analysed by UFLC/ESI-HRMS and MS/MS. The metabolite profiles were compared using partial least square-discriminant analysis. Results - In sterile conditions, aerial parts contained more scopolamine than the roots. However, the diversity of tropane alkaloids was greater in roots. Furthermore, 21 known compounds and four non-elucidated tropane alkaloids were found. The tropane alkaloid profile was shown to be statistically different between sterile and non-sterile hydroponic conditions. The levels of 3-acetoxy-6-hydroxytropane and 3-hydroxylittorine were higher in plants inoculated with A. rhizogenes. Five other tropane compounds were found in higher amounts in non-axenic control plants. Hyoscyamine and scopolamine total contents were much higher in the whole plant co-cultivated with A. rhizogenes TR7 than in controls. Furthermore, the leaves and roots of axenic plants contained more alkaloids than non-sterile ones. Conclusion - In hydroponic conditions, microbes induced variations of the phytochemical levels. Addition of A. rhizogenes TR7 into the nutrient solutions improved the total hyoscyamine and scopolamine production. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Introduction - Maize mutants deficient for the expression of two genes encoding cytosolic glutamine syntehtase (GS) isoenzymes GS1.3 and GS1.4 displayed reduced kernel number and kernel size, respectively, the effect of the mutation being cumulative in the double mutant. However, at maturity, shoot biomass production was not modified in all the mutants, indicating that the reaction catalysed by the enzyme is specifically involved in the control of grain yield. Objective - To examine the physiological impact of the GS mutations on the leaf metabolic profile during the kernel filling period, during which nitrogen is remobilised from the shoots to be further exported to the kernels. Methodology - An 1H-NMR spectroscopy metabolomic was applied to the investigation of metabolic change of the gln1.3, gln1.4 and gln1.3/1.4 double mutant. Results - In the three GS mutants, an increase in the amount of several N-containing metabolites such as asparagine, alanine, threonine and phophatidylcholine was observed whatever the level of nitrogen fertilisation. In addition, we found an accumulation of phenylalanine and tyrosine, two metabolites involved the primary steps of the phenylpropanoid pathway. Conclusion - Changes in the metabolic profile of the GS mutants suggest that, when cytosolic GS activity is strongly reduced, either alternative metabolic pathways participate in the reassimilation of ammonium released during leaf protein remobilisation or that premature leaf senescence is induced when kernel set and kernel filling are affected. The accumulation of phenylalanine and tyrosine in the mutant plants indicates that lignin biosynthesis is altered, thus possibly affecting ear development. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Flax (Linum usitatissimum L.) seed oil, which accumulates in the embryo, and mucilage, which is synthesized in the seed coat, are of great economic importance for food, pharmaceutical as well as chemical industries. Theories on the link between oil and mucilage production in seeds consist in the spatio-temporal competition of both compounds for photosynthates during the very early stages of seed development. In this study, we demonstrate a positive relationship between seed oil production and seed coat mucilage extrusion in the agronomic model, flax. Three recombinant inbred lines were selected for low, medium and high mucilage and seed oil contents. Metabolite and transcript profiling (1H NMR and DNA oligo-microarrays) was performed on the seeds during seed development. These analyses showed main changes in the seed coat transcriptome during the mid-phase of seed development (25 Days Post-Anthesis), once the mucilage biosynthesis and modification processes are thought to be finished. These transcriptome changes comprised genes that are putatively involved in mucilage chemical modification and oil synthesis, as well as gibberellic acid (GA) metabolism. The results of this integrative biology approach suggest that transcriptional regulations of seed oil and fatty acid (FA) metabolism could occur in the seed coat during the mid-stage of seed development, once the seed coat carbon supplies have been used for mucilage biosynthesis and mechanochemical properties of the mucilage secretory cells. [ABSTRACT FROM AUTHOR]

Numerous volatile organic compounds (VOCs) with a large chemical diversity are emitted by plant flowers. They play an important role in the ecology of plants, such as pollination, defense, adaptation to their environment, and communication with other organisms. The Tillandsia genus belongs to the Bromeliaceae family, and most of them are epiphytes. The aromatic profile of the Tillandsia genus is scarcely described. In this study, we use the headspace solid phase microextraction (HS-SPME) coupled with gas chromatography combined with mass spectrometry (GC-MS) method developed in our laboratory to explore the chemical diversity of the VOCs of fragrant flowers of three species of the genus Tillandsia. We were able to identify, for the first time, 66 volatile compounds (monoterpenes, sesquiterpenes, phenylpropanoids, and other compounds). We identified 30 compounds in T. xiphioides, 47 compounds in T. crocata, and 43 compounds in T. caliginosa. Only seven compounds are present in all the species studied. Comparison of the volatile compounds profiles by principal component analysis (PCA) between T. xiphoides, T. crocata, and T. caliginosa species showed a clear difference in the floral emissions of the studied species. Moreover, floral VOCs profiles allowed to differentiate two forms of T. xiphioides and of T. crocata. [ABSTRACT FROM AUTHOR]

The article provides information on the use of nuclear magnetic resonance in metabolite profiling of small molecules for plant metabolism, focusing on polyphenol structural analysis and fruit biology. Topics include biosynthetic precursors for fruit growth, essential for fruit quality and plant biomass.

Lignans, phenolic plant secondary metabolites, are derived from the phenylpropanoid biosynthetic pathway. Although, being investigated for their health benefits in terms of antioxidant, antitumor, anti-inflammatory and antiviral properties, the role of these molecules in plants remains incompletely elucidated; a potential role in stress response mechanisms has been, however, proposed. In this study, a non-targeted metabolomic analysis of the roots, stems, and leaves of wild-type and PLR1-RNAi transgenic flax, devoid of (+) secoisolariciresinol diglucoside ((+) SDG)—the main flaxseed lignan, was performed using 1H-NMR and LC-MS, in order to obtain further insight into the involvement of lignan in the response of plant to osmotic stress. Results showed that wild-type and lignan-deficient flax plants have different metabolic responses after being exposed to osmotic stress conditions, but they both showed the capacity to induce an adaptive response to osmotic stress. These findings suggest the indirect involvement of lignans in osmotic stress response. [ABSTRACT FROM AUTHOR]

Flax for oil seed is a crop of increasing popularity, but its cultivation needs technical improvement. Important agronomic traits such as productivity and resistance to stresses are to be regarded as the result of the combined responses of individual organs and their inter-communication. Ultimately, these responses directly reflect the metabolic profile at the cellular level. Above ground, the complexity of the plant phenotype is governed by leaves at different developmental stages, and their ability to synthesise and exchange metabolites. In this study, the metabolic profile of differently-developed leaves was used firstly to discriminate flax leaf developmental stages, and secondly to analyse the allocation of the metabolites within and between leaves. For this purpose, the concentration of 52 metabolites, both primary and specialized, was followed by gas chromatography (GC-) and liquid chromatography coupled to mass spectrometry (LC-MS) in alternate pairs of flax leaves. On the basis of their metabolic content, three populations of leaves in different growth stages could be distinguished. Primary and specialized metabolites showed characteristic distribution patterns, and compounds similarly evolving with leaf age could be grouped by the aid of the Kohonen self-organising map (SOM) algorithm. Ultimately, visualisation of the correlations between metabolites via hierarchical cluster analysis (HCA) allowed the assessment of the metabolic fluxes characterising different leaf developmental stages, and the investigation of the relationships between primary and specialized metabolites. [ABSTRACT FROM AUTHOR]

Flax (Linum usitatissimum) is a plant grown in temperate regions either for its fiber or for its seeds, which are rich in the essential fatty acid omega-3. It is also well known as a source of medicinal compounds. The chemical composition of its leaves is currently poorly described. In order to fill this gap, we have conducted a comprehensive analysis of flax leaf metabolome. The exploration of the metabolome allowed the characterization of compounds isolated for the first time in flax leaves. These molecules were isolated by preparative HPLC and then characterized by NMR, LC-MS and standard analysis. This work extended our picture of C-glycosyl-flavonoids and coniferyl alcohol derivatives accumulated in flax. The follow-up of the content of these different metabolites via UPLC-MS revealed significant accumulation differences in spring and winter flax leaves. In particular, two methylated C-glycosylflavonoids (swertisin and swertiajaponin) were the most abundant phenolic compounds in winter flax whereas they were not detected in spring flax. This result suggests that these 2 compounds are involved in cold stress tolerance in flax. [ABSTRACT FROM AUTHOR]

Introduction: Biotransformation constitutes an important aspect of the drug discovery process, to mimic human metabolism of active principal ingredient but also to generate new chemical entities. Several microorganisms such as fungi are well adapted to transform drug, whether at the stage of screening or for large-scale production. Objectives: Due to the high chemical complexity of the biotransformation media, it seems attractive to develop new analytical strategies in order to guarantee an adequate monitoring and optimize the production of targeted metabolites or drug candidates. Methods: The model designed for this purpose concerns the biotransformation of a potential histamine H3 antagonist (S38093) in order to produce phase I metabolites. MS, NMR and chemometrics tools were used to monitor biotransformation reactions. Results: First, a screening of eleven filamentous fungi was carried out by UHPLC–UV–MS and principal component analysis to select the best candidates. Subsequently, MS (tR, m/z) and NMR (1H, JRES) fingerprints associated with Consensus OPLS-DA multiblock approach were used to better understand the bioreaction mechanisms in terms of nutrient consumption and hydroxylated metabolites production. Then an experimental design was set up to optimize the production conditions (pH, kinetic) of these target metabolites. Conclusion: This study demonstrates how NMR and MS acquisitions combined with chemometric methods offer an innovative analytical strategy to have a grasp of functionalization mechanisms, and identify metabolites and other compounds (amino acids, nutrients, etc.) in complex biotransformation mixtures. [ABSTRACT FROM AUTHOR]

A global approach that is based on a combination of mass spectrometry (MS) and nuclear magnetic resonance (NMR) data has been developed for a complete and rapid understanding of drug degradation mixtures. We proposed a workflow based on a sample preparation protocol that is compatible to MS and NMR, the selection of the most appropriate experiments for each technique, and the implementation of prediction software and multivariable analysis method for a better interpretation and correlation of MS and NMR spectra. We have demonstrated the efficient quantification of the remaining active pharmaceutical ingredient (API). The unambiguous characterization of degradation products (DPs) was reached while using the potential of ion mobility-mass spectrometry (IM-MS) for fragment ions filtering (HDMSE) and the implementation of two-dimensional (2D) NMR experiments with the non-uniform sampling (NUS) method. We have demonstrated the potential of quantitative NMR (qNMR) for the estimation of low level DPs. Finally, in order to simultaneously monitor multi-samples, the contribution of partial least squares (PLS) regression was evaluated. Our methodology was tested on three indapamide forced degradation conditions (acidic, basic, and oxidative) and it could be easily transposed in the drug development field to assist in the interpretation of complex mixtures (stability studies, impurities profiling, and biotransformation screening). [ABSTRACT FROM AUTHOR]

Introduction: Proton nuclear magnetic resonance spectroscopy (1H-NMR)-based metabolomic profiling has a range of applications in plant sciences. Objectives: The aim of the present work is to provide advice for minimizing uncontrolled variability in plant sample preparation before and during NMR metabolomic profiling, taking into account sample composition, including its specificity in terms of pH and paramagnetic ion concentrations, and NMR spectrometer performances. Methods: An automation of spectrometer preparation routine standardization before NMR acquisition campaign was implemented and tested on three plant sample sets (extracts of durum wheat spikelet, Arabidopsis leaf and root, and flax leaf, root and stem). We performed 1H-NMR spectroscopy in three different sites on the wheat sample set utilizing instruments from two manufacturers with different probes and magnetic field strengths. The three collections of spectra were processed separately with the NMRProcFlow web tool using intelligent bucketing, and the resulting buckets were subjected to multivariate analysis. Results: Comparability of large- (Arabidopsis) and medium-size (flax) datasets measured at 600 MHz and from the wheat sample set recorded at the three sites (400, 500 and 600 MHz) was exceptionally good in terms of spectral quality. The coefficient of variation of the full width at half maximum (FWHM) and the signal-to-noise ratio (S/N) of two selected peaks was comprised between 5 and 10% depending on the size of sample set and the spectrometer field. EDTA addition improved citrate and malate resonance patterns for wheat sample sets. A collection of 22 samples of wheat spikelet extracts was used as a proof of concept and showed that the data collected at the three sites on instruments of different field strengths and manufacturers yielded the same discrimination pattern of the biological groups. Conclusion: Standardization or automation of several steps from extract preparation to data reduction improves data quality for small to large collections of plant samples of different origins. [ABSTRACT FROM AUTHOR]

A selective acylation protocol using cerium chloride (CeCl3) as catalyst was applied to functionalize silybinin (1), a natural antioxidant flavonolignan from milk thistle fruit, in order to increase its solubility in lipophilic media while retaining its strong antioxidant activity. The selective esterification of 1 at the position 3-OH with a palmitate acyl chain leading to the formation of the 3-O-palmitoyl-silybin (2) was confirmed by both mass spectroscopy (MS) and nuclear magnetic resonance (NMR) analyses. The antioxidant activity of 1 was at least retained and even increased with the CUPRAC assay designed to estimate the antioxidant activity of both hydrophilic and lipophilic compounds. Finally, the 3-O-palmitoylation of 1, resulting in the formation of 2, also increased its anti-lipoperoxidant activity (i.e., inhibition of conjugated diene production) in two different lipophilic media (bulk oil and o/w emulsion) subjected to accelerated storage test. [ABSTRACT FROM AUTHOR]