Fucose-containing oligosaccharides play a central role in physio-pathological events, and fucosylated oligosaccharides have interesting potential applications in biomedicine. No methods for the large-scale production of oligosaccharides are currently available, but the chemo-enzymatic approach is very promising. Glycosynthases, mutated glycosidases that synthesize oligosaccharides in high yields, have been demonstrated to be an interesting alternative. However, examples of glycosynthases available so far are restricted to a limited number of glycosidases families and to only one retaining alpha-glycosynthase. We show here that new mutants of two alpha-L-fucosidases are efficient alpha-L-fucosynthases. The approach shown utilized beta-L-fucopyranosyl azide as donor substrate leading to transglycosylation yields up to 91%. This is the first method exploiting a beta-glycosyl azide donor for alpha-glycosynthases; its applicability to the glycosynthetic methodology in a wider perspective is presented.

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Twenty-four new sesterterpenes, compounds 1-24, were isolated from the aerial parts of Salvia dominica. Their structures were elucidated by 1D and 2D NMR experiments as well as ESIMS analysis and chemical methods. The evaluation of the biological activity of Salvia dominica sesterterpenes by means of a panel of chemical and biological approaches, including chemical proteomics, surface plasmon resonance (SPR) measurements, and biochemical assays were realized. Obtained results showed that 18 out of the 24 sesterterpene lactones isolated from Salvia dominica interact with tubulin-tyrosine ligase (TTL) an enzyme involved in the tyrosination cycle of the C-terminal of tubulin, and inhibit TTL activity in cancer cells. Besides, results of our studies provided an activity/structure relationship that can be used to design effective TTL inhibitors.

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The main aim of this work was to study the leaf secondary metabolite profiles of artificially induced tetraploids (2n=4x=48) of Solanum commersonii, a diploid (2n=2x=24) wild potato species. The tetraploid genotypes of S. commersonii were produced by oryzalin treatment. Both HPLC-UV and LC/MS analyses revealed that there were no qualitative differences in the metabolite profiles between the diploid S. commersonii and its tetraploids. By contrast, the results showed that the phenylpropanoid content was generally significantly higher in the tetraploids than in the diploid S. commersonii. Concerning the glycoalkaloids (GAs), the results provided evidence that the content of minor GAs (solanidenediol triose, solanidadienol lycotetraose, and solanidenol lycotetraose) was higher in tetraploids than in the diploid progenitor, while the content of major GAs (dehydrodemissine and dehydrocommersonine) was significantly higher in diploid S. commersonii than in its tetraploid genotypes. The results are discussed from the practical perspective of potato biodiversity enhancement.