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The contamination of grape berries by Botrytis cinerea can drastically damage wine quality, in particular causing colour degradation. In musts obtained from botrytised grapes, SO2 addition is the main means of avoiding oxidation damage due to laccases excreted by the pathogen. However, consumers are becoming increasingly reluctant to accept SO2 addition to wine. Oenological tannins are used for fining wines because of their colloidal properties, and for wine colour stabilisation due to their ability to condense with anthocyanins. They are also known for their antioxidant and antioxidasic properties. They were thus investigated in the present study for their potential as an alternative to SO2 against laccase oxidation.The impact of various types of oenological tannins on musts and wines was studied once added to musts obtained from the Merlot cultivar, comprising 20 % and 50 % botrytised grapes. Laccase activity, antioxidant capacity, composition of phenolic compounds, spectrophotometric and CIELAB colour parameters were assessed in the musts and wines. Sensory analyses were also performed on 3-month-old wines to evaluate the visual, olfactory and gustative consequences of tannin addition. At a 50 % botrytisation rate, the addition of any type of oenological tannins (at a concentration of 100 g/hL) had no effect on laccase activity and did not protect phenolic compounds. However, at the same concentration and at a 20 % botrytisation rate, proanthocyanidin tannins from grape skin were found to be the most promising tannins with simultaneous protective effects, such as an inhibitory effect on laccase enzymes, protection of colour from complete degradation and preservation of some procyanidin compounds.Oenological tannins are promising candidates for protecting wines from Botrytis damage and they induce a differential effect according to their origin and structure. They could be used to reduce the amount of SO2 that is added during vatting. More research is needed to confirm and better understand the mode of action of various tannins at levels lower than the 20 % botrytised rate tested in the present study.

The naranjilla or lulo (Solanum quitoense Lam.) is a little known fruit that originated in the Andes. Commonly consumed as a fresh drink, it is particularly appreciated for its aroma. Besides its organoleptic qualities, the naranjilla also seems to have good antioxidant properties. We therefore studied the physicochemical characteristics of variety "Puyo hybrid"; determined its juice composition; identified its carotenoids and phenolic compounds, using HPLC-DAD and HPLC/ESI-MS, respectively, in each fruit part; and measured the antioxidant capacities of each part, using the ORAC and DPPH methods. We found the following bioactive compounds: all-trans-[bêta]-carotene, 13-cis-[bêta]-carotene, and 9-cis-[bêta]-carotene and the lutein (carotenoids); chlorogenic acids and their hexosides in the flesh and placental tissues, and flavonol glycosides in the skin (phenolic compounds); and many dihydrocaffeoyl spermidines in all three parts of the fruit. The naranjilla appeared to be a fruit with good nutritional potential that can provide the basis for a new fruit-drink flavor or other fruit derived-products.

The volatile compounds from leaves and peels of an interspecific citrus somatic hybrid, Citrus aurantifolia (Christm.) Swing. + Citrus paradisi Macfayden, obtained by fusion of protoplasts from lime, Citrus aurantifolia (cv. Mexican Lime) and grapefruit, Citrus paradisi (cv. Star Ruby), were extracted by pentane: ether (1 : 1) from liquid nitrogen ball-milled leaves and flavedo and examined by GC-MS in comparison to those of its parents. The hybrid quantitatively retained the ability of the lime parent to synthesize in its leaves the major monoterpene aldehydes (neral, geranial) the monoterpene alcohols (nerol, geraniol), and their acetates, and also the capacity of the grapefruit parent to produce a sesquiterpene aldehyde ([beta]-sinensal) in its leaves and nootkatone in its peel. Conversely, synthesis of most sesquiterpene hydrocarbons and long chain aliphatic aldehydes, which are present in the lime parent leaves and peel, was strongly inhibited in the hybrid, as in the grapefruit parent. In comparison to its parents, the hybrid overproduced citronellal in its leaves and [alpha]-sinensal and [beta]-sinensal in its peel. Based on these results, the future prospects for a better understanding of the inheritance mechanisms with regards to aroma biosynthesis in citrus leaves and peels are discussed. (Resume d'auteur)

Major compounds (i.e. phenolic compounds and carotenoids) were analysed in the extracts of the edible part of three tropical fruits: the Andean blackberry, the naranjilla and the tree tomato. Ellagitannins and anthocyanins were predominant in blackberries and phenolic composition can be used to differentiate the two species studied. Similar phenolic composition occurred in red and yellow tree tomato except for anthocyanins which were absent in the yellow tree tomato. Phenolic acids were detected in the naranjilla pulp. Carotenoids were analysed in the fruits. The composition in carotenoids was similar in the two varieties of tree tomato and their vitamin A activity was calculated. Carotenol fatty acid esters were predominant. β-Cryptoxanthin esters and β-carotene were the major carotenoids. The carotenoid content was high compared to literature data, providing an important high vitamin A activity. In blackberries and naranjilla, this class of compounds was found only at trace level. Finally, ORAC values were estimated in different solvent extracts and results were compared with published data in common fruits.

Correspondance auteur: Brillouet J.M. E-mail: brillouet@cirad.fr Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; Fusion of citrus diploid parental protoplasts generates allotetraploid hybrids which do not retain their parental traits with regard to leaf aroma compound biosynthesis. The aim of this study was thus to examine hybrid leaf proteomes in comparison with their parents. Leaf soluble proteins from two citrus allotetraploid hybrids ( mandarin + lime and mandarin + kumquat) and their diploid parents ( mandarin, lime, and kumquat) were submitted to 2-D gel electrophoresis. Leaf proteome maps of the tetraploid hybrids were compared with those of their parents on the basis of the presence/absence of spots and of their spot relative volumes. The two allotetraploid hybrid maps were found closer to that of their mandarin parent than to those of their nonmandarin parents in terms of the presence/absence of spots as well as at a quantitative level. This approach has to be related to the already observed dominance of mandarin in allotetraploids with regard to volatile compound biosynthesis in leaves

International audience; Volatile compounds were extracted by a pentane/ether (1:1) mixture from the leaves of six citrus somatic allotetraploid hybrids resulting from various combinations of lime, lemon, citron, sweet orange, and grapefruit. Extracts were examined by gas chromatography-mass spectrometry (GC-MS) and compared with those of their respective parents. All hybrids having an acid citrus parent exhibit the same relative contents in hydrocarbons and oxygenated compounds as the acid citrus, while the (grapefruit + orange) hybrid behaves similarly to its two parents. When volatile compound contents (mu g g(-1)) are examined in detail, several behaviors are encountered in hybrids and seem to depend on the presence/absence of the considered parental compound and on the corresponding hybrid combination. Meanwhile, the sesquiterpene hydrocarbons are present in all hybrids at concentrations systematically lower than those of the highest parental producers. Statistical analyses show that hybrids exhibit hardly discriminable aromatic profiles, meaning that no strong dominance of one or the other parent was observed in hybrids with regards to the leaf volatile compound production.

Leaves of 13 interspecific and intergeneric citrus somatic allotetraploid hybrids were analysed and com- pared with those of their respective parents (lime, lemons, citron, orange, kumquat, poncirus and mandarin) with regards to their sesquiterpenoid contents (µg/g dry weight). The hybrids do not fully retain their parental traits. Sesquiterpenoid production is much reduced (by ~65-90%) in hybrids compared with the sum of their parents. The peculiar behaviours of some compounds were described. Statistical analyses were conducted on a qualitative (the presence/absence of each compound in parents and hybrids) and quantitative (the recovery of each compound in hybrids expressed as a percent- age of the sum of its concentration in their parents) basis. Mandarin exerts a strong dominance over its derived hybrids by greatly lowering the production of most compounds, while the expression of parental genomes was more balanced in hybrids having grapefruit or sweet orange as a parent. This decrease in the ability to synthesize sesquiterpenoids could be due to both the tetraploid nature of the hybrids and the dominance of one or other parental genome. Copyright © 2005 John Wiley & Sons, Ltd.

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; Three diploid citrus somatic hybrids (cybrids) were produced by fusions combining nucellar callus-derived protoplasts of Willow Leaf mandarin (Citrus deliciosa Ten.) and Commune clementine (Citrus clementina Hort. ex Tan.) with, respectively, leaf protoplasts of Eureka lemon [Citrus limon (L.) Burm.] and Marumi kumquat [Fortunella japonica (Thunb.) Swing.] and leaf protoplasts of Marumi kumquat. Ploidy and origins of the nuclear, chloroplastic, and mitochondrial genomes were investigated by flow cytometry and nuclear and cytoplasmic simple sequence repeat analyses. Volatile compounds were extracted from the leaves of the three cybrids by a pentane/ether (1:1) mixture, analyzed by GC-MS, and compared to those of their parents. The cybrids were found to be very close to their nucleus-giving parent, suggesting that the main information for volatile compounds biosynthesis is contained in the nucleus. However, nucleo-cytoplasmic interactions occurred: the (mandarin + lemon) cybrid, possessing nucleus and chloroplasts of lemon and mitochondria from mandarin, synthesizes more monoterpene alcohols and esters than its nucleus-giving parent; the (clementine + kumquat) cybrid, possessing nucleus from kumquat and organelles from mandarin, synthesizes more monoterpene and sesquiterpene hydrocarbons and sesquiterpene alcohols than its nucleus-giving parent.

International audience; In order to improve protein assignment from peptide mass fingerprints (PMF) in species with incompletely sequenced genomes, the genus-specific mutations deduced from Expressed sequence tag (EST) sequences were included in the complete reading frames of orthologous proteins, resulting in a new searchable in silico protein database. Using this method in tests on four plant species, the MOWSE score of at least 20% more proteins was improved compared to conventional approaches on crude, total proteins, for middle-sized EST projects. Larger contigs are assembled in more important EST projects and this improves the conventional assignment of the most abundant proteins. However, contigs from minor transcripts remain shorter and the assignment of less abundant proteins, such as those isolated following subcellular fractionment, is improved by searching orthologue-EST conceptual chimeras with the PMF spectra. This strategy may be utilized as a tool to identify potential PMF matches that can be then verified by other experimental approaches (tandem mass spectrometry) to ensure the EST matched chimera identification is accurate.

International audience; Volatile compounds were extracted by a pentane/ether (1:1) mixture from the leaves of seven citrus somatic tetraploid hybrids sharing mandarin as their common parent and having lime, Euroka lemon, lac lemon, sweet orange, grapefruit, kumquat, or poncirus as the other parent. Extracts were examined by GC-MS and compared with those of their respective parents. All hybrids were like their mandarin parent, and unlike their nonmandarin parents, in being unable to synthesize monoterpene aldehydes and alcohols. The hybrids did retain the ability, although strongly reduced, of their nonmandarin parents to synthesize sesquiterpene hydrocarbons, alcohols, and aldehydes. These results suggest that complex forms of dominance in the mandarin genome determine the biosynthesis pathways of volatile compounds in tetraploid hybrids. A down-regulation of the biosynthesis of methyl N-methylanthranilate, a mandarin-specific compound, originates from the genomes of the nonmandarin parents. Statistical analyses showed that all of the hybrids were similar to their common mandarin parent in the relative composition of their volatile compounds.