Resveratrol and its oligomers are biologically active compounds. This work brings new insights for the bioproduction of trans-resveratrol with three dimers, pallidol, trans-ε-viniferin, and trans-δ-viniferin, in cell suspension of Vitis labrusca. Conditions of elicitation by methyl jasmonate were optimized for the production of stilbenes using statistical design of experiment. Bio-production of stilbenes was scaled-up to 5 L and in these conditions, trans-resveratrol concentrations reached 237 mg/L, and for pallidol 114 mg/L. The comparison of different elicitation modes (different elicitors, combination with cyclodextrins or adsorbent resin) allowed to reach particularly high concentrations of target molecules: Resveratrol 6.14 g/L, pallidol 0.90 g/L, δ-viniferin 0.54 g/L, and ε-viniferin 0.50 g/L. Scale-up to 20 L-stirring-bioreactor gave similar growth rates to those observed in shake flask culture, with a high production of resveratrol (4.23 g/L) and δ-viniferin (0.76 g/L). This work provides new strategies for the production of stilbenes in plant cell suspension for biological and commercial evaluation.

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Despite the fact that L‐sorbose has been widely used for the synthesis of vitamin C at an industrial level, its use in organic synthesis remains rare. However, a survey of the chemical literature shows that this unusual sugar can be transformed into interesting derivatives.

Sophorolipids represent an important class of natural surfactants with a variety of environmental, cosmetic, and pharmaceutical applications. Despite their promising physicochemical and biological properties, the use of sophorolipids is hampered by the lack of information regarding their individual structure-activity relationships. The major difficulty in isolating pure sophorolipids arises from the high complexity of crude fermentation media composition and from their strong structural similarities. In this work, a centrifugal partition chromatography method was developed in an original gradient elution mode for the separation of sophorolipids produced by the yeast Candida bombicola. Experiments were realized by using three sets of solvent systems composed of n-heptane, ethyl acetate, n-butanol, methanol, and water in different proportions. The separation was performed at 5 mL/min in the ascending mode by increasing progressively the polarity of the organic mobile phase. In these conditions, more than 80% of the sophorolipids present in the initial crude fermentation extract were eluted successively from the most hydrophobic lactone forms to the most hydrophilic acid forms. The structures of the isolated sophorolipids were further elucidated by HPLC and NMR analyses.

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