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Molecular analysis by parallel tandem mass spectrometry (MS/MS) imaging contributes to the in situ characterization of biosynthetic intermediates which is crucial for deciphering the metabolic pathways in living organisms. We report the first use of TOF-SIMS MS/MS imaging for the cellular localization and characterization of biosynthetic intermediates of bioactive γ-lactones rubrynolide and rubrenolide in the Amazonian tree Sextonia rubra (Lauraceae). Five γ-lactones, including previously reported rubrynolide and rubrenolide, were isolated using a conventional approach and their structural characterization and localization at a lateral resolution of ~400 nm was later achieved using TOF-SIMS MS/MS imaging analysis. 2D/3D MS imaging at subcellular level reveals that putative biosynthetic γ-lactones intermediates are localized in the same cell types (ray parenchyma cells and oil cells) as rubrynolide and rubrenolide. Consequently, a revised metabolic pathway of rubrynolide was proposed, which involves the reaction between 2-hydroxysuccinic acid and 3-oxotetradecanoic acid, contrary to previous studies suggesting a single polyketide precursor. Our results provide insights into plant metabolite production in wood tissues and, overall, demonstrate that combining high spatial resolution TOF-SIMS imaging and MS/MS structural characterization offers new opportunities for studying molecular and cellular biochemistry in plants.

In Kenya coffee quality is determined by the grade proportions and beverage quality which are influenced by various factors including variety, shade and altitude. The objective was to characterize the quality of coffee produced by farmers producing traditional varieties and Ruiru 11 under shade or under full sun in Muranga County. One hundred and five farmers from 13 farmers' Cooperative societies were sampled from an altitude of 1300 to 1900MASL. The type of shade was characterized and it was found that in some cases trees along the hedge were observed to cast shade on coffee. In other farms, big trees in the coffee fields provided shade to the coffee below. Cherry was harvested and wet processed. Green coffee was roasted to medium roast, weighed out as whole beans (five cups of each sample). A panel of five judges evaluated the sensory attributes of the samples. Ten sensory attributes assessed for each coffee on a ten point scale: Fragrance/Aroma, flavour, aftertaste, acidity, body, balance, uniformity, clean cup, sweetness and overall perception. Generally, traditional varieties had significantly better fragrance, flavour, acidity and overall perception as rated by the panel. Altitude and shade did not seem to have any significant effect on the sensory characteristics. In terms of defects, coffee berry borer attack was significantly observed irrespective of the variety or whether coffee was under some shade or in full sun. The results are discussed in relation to possible impact of variety, altitude, and shade on coffee quality observing that shade/agro-forestry is one of the upcoming changes of coffee production systems to mitigate against climate change.

La pollution atmosphérique est considérée comme un important facteur de risque dans le développement de pathologies humaines, principalement respiratoires et cardiovasculaires. L’objectif principal de l'étude TriPleR était d’évaluer l’impact, immédiat et retardé, des particules fines en lien avec les sources d’émission. Notre hypothèse était qu’à côté de la distribution des particules selon leur taille, leur contact plus ou moins long avec l’épithélium respiratoire (via le film muqueux) pouvait conduire à une interaction entre la fraction chimique et le tissu, provoquant alors un effet retardé et/ou prolongé dans la réponse cellulaire.

Wild yams (Dioscorea spp.) are medicinal plants rich in secondary metabolites of pharmacological interest, mostly allantoin and steroidal saponins. Their natural populations are overexploited and endangered. Cultivated yams could represent an alternative source of metabolites if interesting varieties could be selected. The objectives of the present study were to develop an HPTLC protocol for the simultaneous quantification of allantoin and steroidal saponins in dried yam powders, to compare species and varieties originating from distant geographical origins and to assess their potential as a source of secondary metabolites. Overall, 1151 accessions belonging to six cultivated species were analysed (1000 acc. from Nigeria, and 146 acc. from Vanuatu) and were compared to five commercial powders of wild yam (D. villosa). Allantoin, dioscin, gracillin, protodioscin, protogracillin and five unknown saponins were quantified. Dioscorea villosa powders varied in content and composition, with allantoin ranging from 0.23 to 22.35 mg/g (DW) and total saponins from 37.36 to 129.97 mg/g. Allantoin was present in the six species, with highest values in D. bulbifera bulbils (20.38 mg/g) and D. cayenensis tubers (17.12 mg/g). Steroidal saponins were quantified in three species, D. cayenensis, D. esculenta and D. rotundata, but were absent in D. alata, D. bulbifera and D. dumetorum. Mean total saponins contents were 42.15 mg/g in D. cayenensis, 17.65 mg/g in D. esculenta and 17/44 mg/g in D. rotundata, with accessions presenting very high values in D. cayenensis (78.31 mg/g) and D. rotundata (69.65 mg/g). For both allantoin and saponins, variation was observed within tubers and the tuber peel was richer than the flesh. Cultivated yam species represent a sustainable source of allantoin and steroidal saponins which could be further increased through conventional breeding.

Large improvements have been realized on the accuracy of the determination of fruit quality. The relevance of the relationship between commonly used quality descriptors and their related chemical contents was here questioned under the influence of water supply reduction and postharvest cold storage. The study relied on three analyses: (1) a correlation table between quality descriptors and compound contents, (2) principal component analysis using the selected variables to see the quality discrimination dictated by treatments; and (3) linear correlation between content and descriptors according to treatments.The results indicate that abiotic parameters applied on mango fruits before or after harvest can affect the relationship between a quality descriptor and the content in compounds it is related to, here between titratable acidity and organic acid content and to a lesser extent between color, represented by hue angle values, and carotenoids, possibly creating bias in the final quality determination. A stronger relation between total soluble solids and total sugar content, were observed under mild abiotic stress.Fruit growth and postharvest storage conditions, such as irrigation and cold storage, can influence the actual correspondence between the compounds contents and the descriptors used to estimate fruit quality, particularly for pulp color, sugars and acids. © 2019 Society of Chemical Industry.

International audience; In citrus, the production of anthocyanin pigments requires the activity of the transcriptional activator Ruby. Consequently, loss-of-function mutations in Ruby result in an anthocyaninless phenotype [1]. Several citrus accessions, however, have lost the ability to produce these pigments despite the presence of wild-type Ruby alleles. These specific mutants have captivated the interest of botanists and breeders for centuries because the lack of anthocyanins in young leaves and flowers is also associated with a lack of proanthocyanidins in seeds and, most notably, with an extreme reduction in fruit acidity (involving about a three-unit change in pH). These mutants have been defined collectively as "acidless" [24]. We have identified Noemi, which encodes a basic helix-loop-helix (bHLH) transcription factor and which controls these apparently unrelated processes. In accessions of Citron, limetta, sweet lime, lemon, and sweet orange, acidless phenotypes are associated with large deletions or insertions of retro- transposons in the Noemi gene. In two accessions of limetta, a change in the core promoter region of Noemi is associated with reduced expression and increased pH of juice, indicating that Noemi is a major determinant of fruit acidity. The characterization of the Noemi locus in a number of varieties of Citron indicates that one specific mutation is ancient. The presence of this allele in Chinese fingered Citrons and in those used in the Sukkot Jewish ritual [5] illuminates the path of domestication of Citron, the first citrus species to be cultivated in the Mediterranean. This allele has been inherited in Citron-derived hybrids with long histories of cultivation.

This work aims to sort cocoa beans according to chocolate sensory quality and phenolic composition. Prior to the study, cocoa samples were processed into chocolate in a standard manner, and then the chocolate was characterized by sensory analysis, allowing sorting of the samples into four sensory groups. Two objectives were set: first to use average mass spectra as quick cocoa-polyphenol-extract fingerprints and second to use those fingerprints and chemometrics to select the molecules that discriminate chocolate sensory groups. Sixteen cocoa polyphenol extracts were analyzed by liquid chromatography-low-resolution mass spectrometry. Averaging each mass spectrum provided polyphenolic fingerprints, which were combined into a matrix and processed with chemometrics to select the most meaningful molecules for discrimination of the chocolate sensory groups. Forty-four additional cocoa samples were used to validate the previous results. The fingerprinting method proved to be quick and efficient, and the chemometrics highlighted 29 m/ z signals of known and unknown molecules, mainly flavan-3-ols, enabling sensory-group discrimination.

The objective of this study was to contribute to the characterization of nutritional potentials, with special attention to the total phenol and condensed tannins content and the effects on in vitro digestibility of some browsing shrub legumes traditionally used for ruminant feeding. The varieties selected were Bituminaria bituminosa var. bituminosa (BBB), Bituminaria bituminosa var. albormaginata (BBA), Chamaecytisus proliferus var. palmensis (CPP), Chamaecytisus proliferus var. canariae (CPC), and Adenocarpus foliosus (AF). Chemical composition, in vitro digestibility, and net energy for lactation (NE) were analyzed and compared among varieties; the effects of total phenol (TP) and condensed tannins (CT) compounds on digestibility were estimated. Condensed tannins ranged from 1 to 5 g/kg DM of tannins, while total phenols ranged from 9 to 32 g/kg DM of tannins. In vitro organic matter digestibility (OMD) ranged from 0.52 to 0.71, and estimated net energy for lactation (NE) ranged from 4.2 to 5.8 MJ/kg DM, with significant differences among all the varieties. This Chamaecytisus varieties (CPC, CPP) have higher feeding values, following CPC > CPP > AF > BBB > BBA in order. Although there were condensed tannins and total phenols in all the shrubs analyzed, total phenol contents differed significantly between the shrubs. The effect of the content of the total phenols and of the tannins condensed in the OMD of the varieties of shrubs analyzed, shows that the higher amounts of total phenols in some of the varieties of shrubs analyzed, increased the in vitro digestibility (OMD) of the shrubs but high amounts of CT decreased OMD.

International audience; Variability in the chemical composition of 614 species is described in a database containing measurements of wood polymers (cellulose, lignin andpentosan), as well as overall extraneous components (ethanol-benzene, or hot water extracts and ash, with a focus on silica content). These measurements were taken between 1945 and 1990 using the same standard protocol. In all, 1,194 trees belonging to 614 species, 358 genera and 89 families were measured. At species level, variability (quantified by the coefficient of variation) was rather high for density (27%), much lower for lignin and cellulose (14% and 10%) and much higher for ethanol/benzene extractives, hot water extractives and ash content (81%, 60% and 76%). Considering trees with at least five different specimens, and species with at least 10 different trees, it was possible to investigate within-tree and withinspecies variability. Large differences were found between trees of a given species for extraneous components, and more than one tree should be needed per species. For density, lignin, pentosan and cellulose, the distribution of values was nearly symmetrical, with mean values of 720 kg/m3 for density, 29.1% for lignin, 15.8% for pentosan, and 42.4% for cellulose. There were clear differences between species for lignin content. For extraneous components, the distribution was very dissymmetrical, with a minority of woods rich in this component composing the high value tail. A high value for any extraneous component, even in only one tree, is sufficient to classify the species in respect of that component. Siliceous woods identified by silica bodies in anatomy have a very high silica content and only those species deserve a silica study.; La variabilité de la composition chimique de 614 espèces est décrite dans une base de données contenant des mesures de polymères du bois (cellulose, lignine et pentosane), ainsi que de l’ensemble des composants externes (extraits éthanolbenzéne ou à l’eau chaude et cendres, en particulier la teneur en silice). Ces mesures ont été effectuées entre 1945 et 1990 selon le même protocole standard. Au total, 1 194 arbres appartenant à 614 espèces, 358 genres et 89 familles ont été mesurés. La variabilité entre les espèces (quantifiée par le coefficient de variation) était plutôt élevée pour la densité (27 %), beaucoup plus faible pour la lignine et la cellulose (14 % et 10 %) et beaucoup plus élevée pour les extractibles éthanol/benzène, les extractibles à l’eau chaude et les cendres (81 %, 60 % et 76 %). En considérant des arbres avec au moins cinq spécimensdifférents et des espèces avec au moins 10 arbres différents, il a été possible d’étudier la variabilité intra-arbre et intraespèce. De grandes différences ont été constatées entre les arbres d’une espèce donnée pour les composants externes, et plus d’un arbre devrait être nécessaire par espèce. Pour la densité, la lignine, le pentosane et la cellulose, la distribution des valeurs était presque symétrique, avec des valeurs moyennes de 720 kg/m3 pour la densité, 29,1 % pour la lignine, 15,8 % pour le pentosane et 42,4 % pour la cellulose. La teneur en lignine variait nettement d’une espèce à l’autre. Pour les composants externes, la distribution était très dissymétrique, avec une minorité de bois riches en ce composant constituant la queue de valeurs élevées. Une valeur élevée pour tout composant externe, même dans un seul arbre, est suffisante pour classer l’espèce à l’égardde ce composant. Les bois siliceux identifiés par les cristaux de silice en anatomie ont une teneur très élevée en silice et seules ces espèces méritent une étude sur la silice.

Depuis les années 80, l’élaboration de couches minces de silice, SiO2 à partir d’orthosilicate de tétraéthyle ((Si(OC2H5)4, TEOS) par dépôt chimique en phase vapeur (CVD) a été largement étudiée pour répondre aux problématiques de la microélectronique. Récemment, l’élargissement de l’éventail d’applications pour les revêtements à base de SiO2 pour l’optique, l’agroalimentaire, le biomédical, l’emballage ou la séparation des gaz, induit une modification des cahiers des charges tant pour les matériaux que les procédés. Il est souvent mis en avant les besoins de : (a) réduire le budget thermique lors de l’élaboration, (b) éliminer la formation de poudres, induites par exemple par une réactivité élevée en présence d’ozone, (c) revêtir des structures complexes, ce qui diminue l’intérêt des procédés plasma. En réponse à ces besoins, cette étude s’intéresse à la structure de couches de SiO2 amorphe élaborées à partir de TEOS et oxygène à pression atmosphérique à des températures Td comprises entre 400°C et 550°C, et corrèle ces caractéristiques à leur résistance à l’abrasion chimique.

European Bronze Age metal armour, that is helmet, cuirass, shield and greaves is considered as one of the peaks of Bronze Age metal work. Within recent projects funded by the Austrian FWF and the European Union within FP7, most of the European Bronze Age body armour could be studied in detail, including chemical and metallographic analyses, analyses of manufacture and usage of the armour, combined with a conventional archaeological study (typology, distribution, development of the armour). Les armures métalliques, avec casque, cuirasse, bouclier et jambières, représentent un des sommets de la métallurgie à l’âge du Bronze. Dans le cadre de projets récents financés par le Fonds autrichien pour la science et par le septième programme-cadre (7e PC) de l’Union européenne, nous avons pu procéder à des recherches approfondies sur les armures de l’âge du Bronze européen, comprenant des analyses chimiques et métallographiques, ainsi qu’une étude de la fabrication et de l’utilisation des armures, en conjonction avec une enquête archéologique classique (typologie, répartition, évolution de l’armure).

International audience; The genus Nasutitermes is among the most abundant wood-feeding Termitidae and an extremely diverse and heterogeneous group in terms of its biogeography and morphology. Despite the major role of several Nasutitermes species as structural pests, the phylogenetic status of this genus is still unclear, along with a confused taxonomy and species identification remaining difficult. The first aim of this review was thus to gather and discuss studies concerning the taxonomic status of the genus Nasutitermes in order to clarify this crucial point. Then, our goal was to gain new insights into the management of N. corniger, considered to be the most economically detrimental pest of this genus in South America and a Nasutitermes model species, while filtering available information concerning its biology through the prism of termite control, as well as critically examine the existing methods. We indeed strongly believe that increasing our knowledge of this species’ biological strategies is the key to progress in the challenging question of their sustainable management.

The objective of this work is to compare mass loss and chemical evolution of the solid phase, versus time, during dynamic torrefaction of different types of biomass. For this purpose, two experiments, ThermoGravimetric Analysis and solid-state 13 C Cross-Polarization/Magic Angle Spinning Nuclear Magnetic Resonance, were run on four representative biomasses. Overall mass loss and chemical evolution of the solid phase were followed, respectively, as a function of temperature and time. Thanks to this coupled information, it was shown that the knowledge of both solid mass loss and chemical evolution is necessary to characterize torrefaction severity. Moreover, biomasses containing higher proportions of xylan lost mass faster than those containing lower proportions. Lignin showed a protecting role towards cellulose, which would lead to a faster degradation of non-woody biomasses in comparison with woody biomasses. Three parameters would have an influence on solid chemical evolution during torrefaction: xylan content in hemicellulose, lignin content in biomass, and cellulose crystallinity.

The starchy corms of taro (Colocasia esculenta) are consumed throughout the tropics and are essential for food security in many developing countries. Taro corms are increasingly processed into fries, chips, flours or flakes in urban areas, and varieties with attractive corm flesh colours are now needed. The identification of flavonoids in taro corms would add value to this crop. The present study developed a high-performance thin layer chromatography (HPTLC) protocol for the high-throughput screening of flavonoids in taro germplasm. Overall, 350 different accessions were analysed including 259 varieties from Vanuatu, one from Vietnam, eight from Thailand, eight from the Philippines, six from Malaysia, two from Japan and 18 from Indonesia. Forty-eight breeding lines (hybrids) including 21 from Vanuatu, 21 from Samoa, four from Hawaii and two from Papua New Guinea were also analysed. Ten flavones, namely luteolin-6-C-hexoside-8-C-pentoside, schaftoside, luteolin-3′,7-di-O-glucoside, homoorientin, isovitexin, orientin, luteolin-4′-O-glucoside, luteolin-7-O-glucoside, vitexin and apigenin-7-O-glucoside, were successfully detected in the corm and are responsible for the attractive yellow colour of the flesh and fibres. Quantitatively, luteolin-6-C-hexoside-8-C-pentoside and schaftoside were the most important of all the detected flavonoids. However, only 18% of the varieties analysed presented these two compounds and 80% presented poor flavonoid composition. No geographical structure of the variation was detected and the most flavone-rich varieties originated from Vanuatu, Thailand, the Philippines, Malaysia and Indonesia. The compounds detected in the present study were significantly and positively correlated, suggesting that there is potential for fast improvement through controlled crosses, subsequent evaluation of full-sib progenies and cloning of elite individuals.

International audience; Torrefaction is a mild thermal pretreatment which improves biomass properties and releases condensable species. Condensable species released during torrefaction of pine, ash wood, miscanthus and wheat straw at 250, 280 and 300 °C were investigated. A fixed-bed reactor was used for the laboratory scale experiments. A micro-GC, Karl Fischer titrator and GC-MS were used to analyse incondensable gases, water and other condensable species, respectively. The overall mass balance ranged from 96 to 103 wt.%. The quantification rate of condensable species was on average 77 wt.%. In addition to the major species usually reported in the literature – water, acetic acid, 2-propanone,1-hydroxy- – we show that large amounts of some anhydrosugars were produced. Additionally, 85 condensable species were identified. Among these species, many terpenes and terpenoids in pine were identified by adsorption on SPME fibre. Finally, the influence of temperature and of the nature of biomass on the yields of condensable species was highlighted.

In this study an analytical multi-technique approach was developed in order to describe as fully as possible the composition of several fast pyrolysis oils. Six bio-oils were produced at CIRAD (centre de Cooperation Internationale en Recherche Agronomique pour le Developpement) and TI (Thunen Institute of Wood Research) using the same three lignocellulosic biomass materials (i.e. hardwood, softwood and wheat straw). Different and complementary analytical tools were used to characterize these samples. Whole bio-oils were first directly analyzed by gas chromatographic (GC) hyphenated techniques with flame ionization detector (FID) and mass spectrometry (MS) (Headspace-GC-FID/MS, GC-FID/MS) and by a high resolution mass spectrometry technique (Fourier transform ion cyclotron resonance mass spectrometry FT-ICR/MS) without any pre-separation step. The GC analyses provide a detailed molecular description (more than 90 compounds) of the composition of the six bio-oils. To achieve a better understanding of the chemical composition of this set of bio-oils, the samples were fractionated into aqueous fractions and water-insoluble fractions (also called pyrolytic lignins). Detailed analysis of sugars was performed by GC-FID/MS after a solid-phase extraction (SPE) and a subsequent derivatization performed on the aqueous fractions. Moreover, FT-ICR/MS analyses show that species having molecular weights up to 900 Da are present in the aqueous phases. The originality of this work is based on the development of complementary analytical tools (i.e., chromatographic and spectrometric techniques) to describe the composition from volatiles (monomeric) to non-volatiles (oligomeric) species of several bio-oils that were produced and stored under controlled conditions. (Resume d'auteur)

International audience; Volatile components of seven species of the Bazzanioideae sub-family (Lepidoziaceae) native to New Caledonia, including three endemic species (Bazzania marginata, Acromastigum caledonicum and A. tenax), were analyzed by GC-FID-MS in order to index these plants to known or new chemotypes. Detected volatile constituents in studied species were constituted mainly by sesquiterpene, as well as diterpene compounds. All so-established compositions cannot successfully index some of them to known chemotypes but afforded the discovery of new chemotypes such as cuparane/fusicoccane. The major component of B. francana was isolated and characterized as a new zierane-type sesquiterpene called ziera-12(13),10(14)-dien-5-ol (23). In addition, qualitative intraspecies variations of chemical composition were very important particularly for B. francana which possessed three clearly defined different compositions. We report here also the first phytochemical investigation of Acromastigum species. Moreover, crude diethyl ether extract of B. vitatta afforded a new bis(bibenzyl) called vittatin (51), for which a putative biosynthesis was suggested.

International audience; The chemical composition (CC), antioxidant capacity (AC) and oxygen consumption rate (OCR) of 36 different commercial tannins were measured. The CC was analyzed by total polyphenol index, Bate-Smith, methyl-cellulose, Folin-Ciocalteu, OIV official method and phloroglucinolisis. The AC was measured by different methods (ABTS, CUPRAC, DPPH, FRAP, ORAC) using Trolox as standard. The OCR was measured using a non-invasive method based on luminescence. The results indicate that it is possible to obtain differentiation between procyanidins/prodelphinidins, profisetinidins/prorobinetidins, gallotannins and ellagitannins by PCA based on their CC data. It is also possible to separate condensed from hydrolysable tannins by PCA based on their AC data. The results show that ellagitannins are the fastest oxygen consumers of the various oenological tannins, followed in descending order by condensed tannins and finally gallotannins. The combination of CC, AC and OCR analyses enable to classify tannins according to their effectiveness in protecting wines against oxidation.

The aim of this study was to investigate the effect of torrefaction on the pyrolysis of rubber wood sawdust (RWS) using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Three typical torrefaction temperatures (200, 250, and 300 °C) and pyrolysis temperatures (450, 500, and 550 °C) were considered. The results suggested that only diethyl phthalate, belonging to esters, was detected at the torrefaction temperatures of 200 and 250 °C, revealing hemicellulose degradation. With the torrefaction temperature of 300 °C, esters, aldehydes, and phenols were detected, suggesting the predominant decomposition of hemicellulose and lignin. The double-shot pyrolysis indicated that the contents of oxy-compounds such as acids and aldehydes in pyrolysis bio-oil decreased with rising torrefaction temperature, implying that increasing torrefaction severity abated oxygen content in the bio-oil. With the torrefaction temperature of 300 °C, relatively more cellulose was retained in the biomass because the carbohydrate content in the pyrolysis bio-oil increased significantly.

Large worldwide sources of dust, such as the Saharan desert, play a key role in the amounts and composition of atmospheric particulate deposition (APD), but their relative contribution compared to other sources remain unclear. Our study aimed to apportion Saharan, regional, and anthropogenic sources of APD in three sampling along a long transect affected by Saharan outbreaks. We quantified total APD, and analyzed its mineralogical and chemical composition between 2011 and 2012. . Strong markers of Saharan dust, such as large amounts of APD and of a low Al2O3:CaO ratio allowed identifying clear periods influenced by Saharan outbreaks. Nitrogen and phosphorus reflected soil affected by agricultural practices, while Cd, Pb, Sb and Sn tracked traffic and industrial sources – as confirmed by enrichment factors. Then, we designed a conceptual model including sensitivity analyses to estimate the contribution of unanalyzed (10–11%, likely chlorites or sulfates), organic (34–41%), anthropogenic (11–22%), mineral-regional (5–25%) and mineral-Saharan (10–38%) matter over our entire study period. Our study shows the rapidly decreasing contribution of Saharan outbreaks – and the decreasing flux of Ca and Mg, from 40 to 0.4 kg.ha−1 over the study period between Algeria and France. Yet, Saharan outbreaks were still noticeable in APD at a site 1500 km away. Our study also shows the large relative contribution of organic and anthropogenic sources to APD in the three sampling sites, and their possible influence on nutrient budgets.

The effect of solar and electric drying on physicochemical composition of onion (Allium cepa L) has been studied to reduce the post-harvest losses of onion bulbs. The physicochemical and biochemical composition of three varieties of onion (White of galmi, Violet of galmi and Goudami) were also investigated using the Fourier transform infrared (FT-IR) spectroscopy (4000-400 cm- 1) and scanning electron microscopy (SEM). Protein, sugar, lipid, moisture, ash, vitamin C, and color parameters were assayed on fresh and dried onion powders. The results showed that water was the main constituent of the fresh onion bulbs (87%). They were also rich in available sugars ranging from 19 g to 59 g/100 g and proteins 4 g to 11 g/100 g of dry matter (DM). Moreover, Ca, K, P, and Mg were found to be the major minerals of the onion powders. In general, the drying process influenced significantly (P

The use of natural fibers such as hemp (Cannabis sativa L.) as substitutes for nonrenewable fibers increases the life cycle performance of composite materials. The management of retting in fields as a natural pretreatment prior to fiber extraction remains challenging due to a lack of knowledge about the relative importance of environmental and biotic factors, which continually interact under field conditions. Here, we studied the dynamics of hemp retting under controlled air temperature and humidity conditions and with simulated rain. We tracked the color and infrared spectral absorbance of the stem surface, the chemical composition and microbial enzyme activities of the bast tissues, and the stem architecture over 42 days at 15 °C. Color changes on the stem surfaces were the first indicators of retting progress, with a significant decrease in the L*, a* and b* values (CIELAB) from day 14 onward. These findings were closely correlated with the surface colonization progress as revealed by scanning electron microscopy, the changes in enzymatic activities and the decohesion of the bast tissues. Additional investigations are needed to study other environmental scenarios to provide an accurate assessment of the retting process over time.

The variability of natural rubber (NR) properties has been partly ascribed to the 3 to 5% non-isoprene components (lipids, proteins, carbohydrates and minerals) present in NR. Of all the factors that might be held responsible for this variability, clonal origin has appeared to be prominent. The sugars and polyols of latex from five Hevea brasiliensis clones (RRIM600, GT1, PB235, PB260 and PB217) were extracted with ethanol after specific NR sample pretreatment in a cyclohexane/ethanol solution. Latex carbohydrates were characterised by high performance anion-exchange chromatography equipped with a pulsed amperometric detector (HPAE-PAD). Total extractable carbohydrates, single sugars and polyols were analysed for each clone to evaluate how clonal origin affected the variability of latex carbohydrate compositions. Significant clonal differences were identified, both in the total sugar and polyol contents of the latex, and in the quantity of each element. The differences between the latex extracts of clones GT1, PB217, PB260, PB235 and RRIM600 did not come solely from the presence of major carbohydrates, such as quebrachitol or sucrose, but also effectively from minor carbohydrates, such as sorbitol or galactose. Some minor carbohydrates could even be used as biochemical clone indicators.

Bacterial wilt, caused by Ralstonia solanacearum, is a major plant disease throughout the Caribbean. The ability of the essential oil from Pimenta racemosa var. racemosa to control bacterial wilt of tomato (R. solanacearum, phylotype IIB/4NPB) was investigated. Lemongrass (chemotype 1)-, aniseed (chemotype 2)-, and clove (chemotype 3)-scented chemotypes of P. racemosa var. racemosa essential oil were tested. Six concentrations of emulsified essential oil (from 0.01 to 0.14% [v/v]) were evaluated by in vitro culture amendment assays and by in vivo experiments in greenhouse. Chemotype 3 displayed remarkable in vitro antibacterial activity against R. solanacearum, because the minimum inhibitory concentration was only 0.03%, compared with 0.14% for chemotypes 1 and 2. In greenhouse experiments, no incidence of bacterial wilt was observed in tomato plants grown in soil treated with chemotype 3 of P. racemosa var. racemosa at a concentration of 0.14%. In the untreated control soil, 62% of plants displayed symptoms of bacterial wilt. Treatment with chemotype 3 significantly increased the growth of tomato plants compared with untreated controls. These results suggest that chemotype 3 of P. racemosa var. racemosa essential oil is a good candidate for further development as a soil biofumigant for the control of tomato bacterial wilt.

In order to investigate the effect of potassium addition on the composition of torrefaction condensates, two demineralized wood species were impregnated with different concentrations of K2CO3 and then torrefied at 275 °C up to an anhydrous weight loss (AWL) of 25%. Torrefaction was carried out in both a thermogravimetric analysis (TGA) instrument and a laboratory fixed-bed reactor. Condensates from the fixed bed reactor were collected and analyzed by Gas Chromatography-Mass Spectroscopy (GC–MS). TGA of raw and K2CO3-impregnated biopolymers (cellulose, xylan and lignin) were performed to facilitate interpretation of the results. TGA showed that when potassium content increased in the biomass, shorter torrefaction times were sufficient to obtain the targeted AWL. GC–MS showed, for both wood species, that potassium promotes the formation of acetol and slightly enhances acetic acid yield. The amount of some lignin derivatives (guaiacol, syringol, 4-vinylguaiacol) also rose with potassium addition. Yields of levoglucosan, LAC (1-hydroxy-(1R)-3,6-dioxabicyclo[3.2.1]octan-2-one) and DGP (1,4:3,6-dianhydro-α-d-glucopyranose), as well as furfural and 5-hydroxymethylfurfural, decreased drastically in the presence of potassium. In conclusion, small additions of potassium carbonate deeply affected thermal degradation of wood species and the speciation of torrefaction condensates. (Resume d'auteur)

The management of livestock systems for technical, economic and environmental optimization requires an increasingly accurate formulation of rations and therefore a detailed knowledge on the feeds consumed by animals. Near-infrared spectrometry (NIRS), which has been used increasingly since the 1960s, is an analytical technique that allows rapid characterization of feeds or forage samples. The first applications developed were on the chemical composition of the feeds, but it is also possible to develop calibrations for the estimation of the nutritional value and the feed intake. Beyond these direct measurements on the feed, NIRS can also be applied to faeces to characterize the feeding of animals on rangelands. Joint consideration of feed and feces spectra can give a picture of how animals actually use feeds. Other possible uses of NIRS such as traceability or feed classification and botanical recognition of plants in grasslands are also described. The current technical developments, and in particular the miniaturization of spectrometers, make it possible to bring the instruments on the field to produce information as close as possible to its use. Other spectroscopic techniques that are alternative or complementary to NIRS such as mid-infrared spectroscopy, Raman spectroscopy or hyperspectral imaging will allow other measurement conditions and other applications., Le pilotage des systèmes d’élevage en vue d’une optimisation technique, économique et environnementale passe par une formulation des rations de plus en plus précise et nécessite donc une connaissance fine des aliments consommés par les animaux. La spectrométrie dans le proche infrarouge (SPIR), utilisée de façon croissante depuis les années 60, est une technique analytique permettant de caractériser rapidement des échantillons d’aliments ou de fourrages. Les premières applications concernaient la composition chimique des fourrages, mais il est également possible de développer des étalonnages pour une estimation de la valeur nutritive et de l’ingestion. Au-delà de ces mesures directes sur l’aliment, la SPIR peut être appliquée sur les fèces afin de caractériser l’alimentation d’animaux sur parcours. Le traitement conjoint des spectres des aliments et des fèces peut donner une vision de l’utilisation réellement faite des aliments par les animaux. D’autres utilisations possibles de la SPIR comme la traçabilité ou la classification des aliments ainsi que la reconnaissance botanique des végétaux dans les prairies sont aussi décrites. Les développements techniques actuels, et notamment la miniaturisation des spectromètres, permettent d’amener les instruments sur le terrain pour produire l’information au plus près de son utilisation. D’autres techniques spectroscopiques alternatives ou complémentaires à la SPIR comme la spectroscopie dans le moyen infrarouge, la spectroscopie Raman ou l’imagerie hyperspectrale permettront d’autres conditions de mesures et d’autres applications.

Two series of compounds showing mass signals at m/z 605 and 893 (negative ionization mode) have been detected in fermented cocoa beans. This study objective is to identify these mass signals and characterize their structure in fermented cocoa samples. Our hypothesis is that these signals may correspond to ethyl-bridged flavan-3-ols resulting from flavan-3-ol condensation with acetaldehyde which is a microbial metabolite. Mass spectrometry was used to compare the retention times and mass fragmentation patterns between a model solution using epicatechin and procyanidin dimer B2, the major flavan-3-ols of cocoa, as precursors and extracts of fermented cocoa. Their identification was confirmed: four isomers of ethyl-linked epicatechin as well as several isomers of epicatechin-ethyl-procyanidin B2, in which B2 was mostly linked through its upper unit, were characterized in cocoa. This study demonstrates the presence of flavan-3-ol acetaldehyde condensation products in fermented cocoa beans and provides the first report of epicatechin-ethyl-procyanidin B2.

Thirty-four Eucalyptus urophylla × Eucalyptus grandis hybrids were evaluated with a view to selecting for improved growth and wood-quality traits for plantations in the Congo. Height, circumference at breast height and volume were measured at 12, 27, 37, 49 and 60 months. Lignin content, the syringyl/guaiacyl ratio and total extractives content were predicted by near-infrared spectroscopy using wood powder samples collected from trees at breast height. While wood chemical properties were stable and under strong genetic control, growth traits were not. The genetic correlation between lignin content and growth was weak and negative, whereas the environmental correlation was also weak but positive. The genetic improvement of E. urophylla × E. grandis clones, based on growth features, leads to a limited decrease in lignin content and syringyl content and to a limited increase in extractives content.Keywords: genetic and environmental correlations, genetic gain, NIRS

Food losses can occur during production, postharvest, and processing stages in the supply chain. With the onset of worldwide food shortages, interest in reducing postharvest losses in cassava has been increasing. In this research, the main goal was to evaluate biochemical changes and identify the metabolites involved in the deterioration of cassava roots. We found that high levels of ascorbic acid (AsA), polyphenol oxidase (PPO), dry matter, and proteins are correlated with overall lower rates of deterioration. On the other hand, soluble sugars such as glucose and fructose, as well as organic acids, mainly, succinic acid, seem to be upregulated during storage and may play a role in the deterioration of cassava roots. Cultivar Branco (BRA) was most resilient to postharvest physiological deterioration (PPD), while Oriental (ORI) was the most susceptible. Our findings suggest that PPO, AsA, and proteins may play a distinct role in PPD delay., This work was supported by PEC-PG ("Programa de Estudantes Convenio de Pos-Graduacao") coordinated by CAPES ("Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior"), CNPq, TWAS-Fellowship for Advanced Research and Training (FR Number 3240268144) and CIAT (International Center for Tropical Agriculture).

In the Mediterranean region, the use of small-mesh netting to protect horticultural crops is an effective sustainable tool against pests. But in tropical regions, because of high humidity under the net favoring fungal development, netting with a larger mesh size has to be used, protecting crops against lepidopteran pests but not against small pests such as hemipterans, thrips, and phytophagous mites. A combination of netting with a repellent or irritant product is one possible solution, but the desire to reduce the use of synthetic chemicals and mitigate resistance issues calls for a natural alternative. The objective of this study was to evaluate the repellent, irritant, and toxic effects of nets dipped in 20 different plant extracts on Bemisia tabaci (Gennadius) adults. The repellent effect of volatile compounds was evaluated using a still-air olfactometer. The irritant effect and toxicity were evaluated with a no-choice test in tubes separated into two parts by an impregnated net. Our results showed the seven most irritant and toxic products against B. tabaci were aframomum, cinnamon, geranium, dill, citronella, litsea, and savory. The most repellent were aframomum and lemongrass, although cinnamon, geranium, and savory were also repellent at higher doses. Effects varied with the plant extract and the concentration, and effects were independent of one another, i.e., an essential oil can be irritant but not repellent, suggesting that the repellent mechanism and that behind the irritant or toxic effects is not the same. The use of repellent compounds in combination with netting as new pest control strategy is discussed.

An extensive characterization was carried out on various biomass samples representative of the diversity in France, including forestry samples (softwood and hardwood woodchips, eucalyptus and poplar short rotation coppices), very short rotation coppices (VSRC) samples and agricultural samples (wheat straw, triticale, fescue, miscanthus and switchgrass). The following properties were measured to evaluate suitability with thermochemical process: elemental analysis (C, H, O, N, S, and Cl), chemical composition (extractives, lignin, mono/polysaccharides, acetate groups), ash content and inorganic composition. Carbon and hydrogen contents are quite similar between biomasses. Agricultural biomasses are usually less oxygenated than forestry biomasses. Nitrogen content is generally higher for agricultural biomasses (up to 1.4 %) than for forestry biomasses, but important amount is also found in VSRC (0.8 % for poplar). Chlorine and sulfur are species-dependent. Fescue and eucalyptus show high values of Cl, while wheat straw has the highest sulfur content. Ash content is very low for forestry and perennial biomasses (miscanthus and switchgrass). For non-perennial crops, values up to 8.5 % (wheat straw) were measured. Agricultural biomasses contains more silicon (2 % for triticale), magnesium (0.16 % for fescue), potassium (1.9 % for fescue) and phosphorus (0.18 % for fescue), while forestry biomasses are richer in calcium (up to 0.97 % for poplar VSRC). Other inorganic elements, especially heavy metals are present in very low concentrations and most of the time below detection limits. Regarding chemical composition, extractive content is very high (20–25 %) for non-perennial crops (fescue, wheat straw and triticale) and eucalyptus VSRC. Lignin content seems to be higher for forestry biomasses (21–29 %) than for agricultural biomasses (16–23 %). The same trend was observed for cellulose, while the opposite was observed for hemicelluloses. These differences in organic and inorganic composition are expected to significantly impact the behavior of these biomasses in thermochemical processes such as gasification for biofuels production.

Influence of chitosan coating with or without the active antimicrobial lactoperoxidase system was studied on postharvest mangoes. Mangoes were treated with three concentrations of chitosan (0.5; 1; 1.5%) containing or not lactoperoxidase with or without iodine as a second electron donor. Coatings containing 1 and 1.5% chitosan incorporated with lactoperoxidase system efficiently inhibited fungal proliferation and delayed mango ripening. Iodine did not influence antifungal activity. Ripening parameters (firmness, respiration, weight loss and color) were not influenced by the lactoperoxidase system, but were more influenced by chitosan concentration. Chitosan coating alone reduced weight loss, and delayed the decline in firmness and respiration rate. It exhibited a beneficial effect on the contents of total soluble solids (TSS), ascorbic acid, total acidity (TA) and pH.

Description du sujet. Le bilan des nutriments, l'homogénéité des andains ainsi que l'hygiénisation, évaluée par la température, de composts obtenus lors du co-compostage de boues de laiterie et de fumier de bovins ont été étudiés à la demande de l'industrie laitière réunionnaise qui souhaite développer la valorisation agronomique des boues de laiterie en satisfaisant les contraintes règlementaires de l'Ile de la Réunion. Objectifs. Les objectifs de cette expérimentation étaient d'évaluer la faisabilité d'un co-compostage de fumier de bovin avec des boues de laiterie et de statuer sur la qualité du compost produit. Méthode. Trois andains de fumier avec deux doses de boues de laiterie ont été mis en place (sur une base massique) : fumier seul (T), fumier ⅔ + boues ⅓ (B1) et fumier ½ + boues ½ (B2) présentant une densité brute de 305, 566 et 630 kg·m-3 et une porosité libre à l'air de 72 %, 48 % et 42 %, respectivement. Un retournement a été effectué après 21 jours. Le compostage a été prolongé durant 142 jours. Résultats. Les résultats obtenus montrent que les températures des tas atteignent 70 °C après deux jours de compostage et que l'hygiénisation (t > 55 °C) dure 40, 29 et 34 jours pour les andains T, B1et B2, respectivement. L'andain T a perdu 69 % de sa masse et 64 % de son volume initial pendant le compostage, l'andain B1, 71 % et 44 % et l'andain B2, 68 % et 49 %, respectivement. Les matières minérales et les éléments fertilisants se sont concentrés dans la matière sèche (MS). L'andain T a perdu 54 % de sa matière organique (MO) et 15 % de son azote (N), l'andain B1, 51 % et 42 % et l'andain B2, 56 % et 50 %, respectivement. Les teneurs en MS et en N deviennent plus homogènes au sein du tas pour les andains T et B1 contrairement au tas B2. Conclusions. Les composts obtenus sont conformes à la norme NFU 44-51 (T) et à la norme NFU 44-95 (B1 et B2), sauf pour le critère de teneur en MS pour ces derniers. Par rapport au compost de fumier de bovin, le compost avec ajout de boues (⅓) est enrichi (sur une base matière fraiche) en N (+ 15 %), en P (+ 40 %) et appauvri en K (- 20 %).