The treatment of grape berries (Vitis vinifera L. cv. Cabernet Sauvignon) with the ethylene-releasing compound, 2-chloroethylphosphonic acid (2-CEPA), at veraison is a method known to enhance grape skin colour. We observed that it produced a 6-fold increase, up to 30 pmol g À1 FW, of the cluster internal ethylene compared to untreated controls within the 24 h following treatment. This ethylene upsurge was associated with increased levels of chalcone synthase (CHS) and flavanone 3-hydroxylase (F3H) transcripts, which persisted over the following 20 days. Transcript levels of leucoanthocyanidin dioxygenase (LDOX) and UDP glucose-flavonoid 3-O-glucosyl transferase (UFGT) were similarly enhanced by 2-CEPA, although to a lesser extent. The effect on UFGT was confirmed at the protein level by an immunoblot analysis. The transcript accumulation of dihydro-flavonol 4-reductase (DFR) was unaffected by 2-CEPA treatment. Examination of the levels of CHS, F3H and UFGT mRNAs in berries during bunch exposure to ethylene, revealed elevated levels of each transcript within the first 6 h of treatment when compared to nonethylene-treated controls. HPLC analyses of berry skin extracts showed that levels of each of the anthocyanins analysed (delphinidin, cyanidin, petunidin, peonidin and malvidin) increased over the 10 days following the ethylene burst, and decreased thereafter. However, anthocyanin levels at harvest were still higher in ethylene treated grapes than in controls. This data is the first evidence that ethylene triggers gene expression related to anthocyanin synthesis in grapes, and in addition, our results also confirm the existence of other regulatory modes in the anthocyanin biosynthetic pathway.

Critical fouling conditions were studied during wine cross-flow microfiltration using a multichannel ceramic membrane (0.2 m). The aim was to determine critical operating conditions in order to limit fouling caused by wine colloids (tannins, pectin and mannoproteins) and enhance process performances. The method used is a square wave filtration based on the determination of the reversibility and irreversibility of fouling. Filtrations were performed with filtered red wine (FW) added with different concentrations of colloids. Considering FW, critical flux for irreversibility was beyond the studied range of pressure (≥1.4 × 10 −4 m/s). No clear critical flux could be determined for any of the tested molecules in the studied range of pressure. On the other hand, an upper limit of fluxes range has been identified (below which critical flux could be found). Irreversible fouling always takes place from the beginning of the filtrations and even at low pressures. For FW containing 0.2 g/l mannoprotein and 0.5 g/l pectin, a loss of average fluxes is observed beyond a given limit of transmembrane pressure. This fact was attributed to the compaction of a gel layer. Finally, a criterion (R if /R m ≤ 1) has been suggested to determine the so-called "threshold flux" below it, fouling remains acceptable.

The main simple phenolic compounds in plum likely to have an effect on the quality of the fruit were investigated by HPLC. Evolution of the compounds and of polyphenoloxidase (PPO) was monitored during the first phase of drying under the effect of different temperatures. The d'Ente plum is characterized by a high neochlorogenic acid content. Neochlorogenic acid content is 2.4 times as high

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Naphtho-γ-pyrones (NGPs) are secondary metabolites mainly produced by filamentous fungi (Fusarium sp., Aspergillus sp.) that should be considered by industrials. Indeed, these natural biomolecules show various biological activities: anti-oxidant, anti-microbial, anti-cancer, anti-HIV, anti-hyperuricuric, anti-tubercular, or mammalian triacylglycerol synthesis inhibition which could be useful for pharmaceutical, cosmetic, and/or food industries. In this review, we draw an overview on the interest in studying fungal NGPs by presenting their biological activities and their potential values for industrials, their biochemical properties, and what is currently known on their biosynthetic pathway. Finally, we will present what remains to be discovered about NGPs.

Background: Black Aspergilli represent one of the most important fungal resources of primary and secondary metabolites for biotechnological industry. Having several black Aspergilli sequenced genomes should allow targeting the production of certain metabolites with bioactive properties. Results: In this study, we report the draft genome of a black Aspergilli, A. tubingensis G131, isolated from a French Mediterranean vineyard. This 35 Mb genome includes 10,994 predicted genes. A genomic-based discovery identifies 80 secondary metabolites biosynthetic gene clusters. Genomic sequences of these clusters were blasted on 3 chosen black Aspergilli genomes: A. tubingensis CBS 134.48, A. niger CBS 513.88 and A. kawachii IFO 4308. This comparison highlights different levels of clusters conservation between the four strains. It also allows identifying seven unique clusters in A. tubingensis G131. Moreover, the putative secondary metabolites clusters for asperazine and naphthogamma-pyrones production were proposed based on this genomic analysis. Key biosynthetic genes required for the production of 2 mycotoxins, ochratoxin A and fumonisin, are absent from this draft genome. Even if intergenic sequences of these mycotoxins biosynthetic pathways are present, this could not lead to the production of those mycotoxins by A. tubingensis G131.

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