Sorbitol transformations

Vilcocq, L., Koerin, R., Cabiac, A., Especel, C., Lacombe, S., Duprez, D., 2014. New bifunctional catalytic systems for sorbitol transformation into biofuels. Applied Catalysis B Environmental 148-149,499-508. 

A similar series of reactions applied to L-sorbose (once a rare sugar but now easily obtained from sorbitol by bacterial oxidation16) gives rise to 2-keto-L-gulonic acid.4 The method is not confined to keto-hexoses and has been employed in the preparation from L-erythropentulose (XXXI) of the 2-keto-L-ribonic acid (XXXV) which undergoes immediate transformation to the corresponding L-erythroascorbic acid (XXXVI).16... 

By far the most important oxidation of the hexitols is their specific biochemical transformation to ketoses. The history of this reaction dates from the fortuitous discovery of L-sorbose in mountain ash berries by Pelouze in 1852. It was not until twenty years later that Boussin-gault showed that it had arisen by bacterial oxidation of sorbitol. 

As recently reviewed by Abbadi and van Bekkum,[51] the most important carbohydrate hydrogenation reaction is the transformation of glucose into sorbitol (Scheme 7.4). The world production of sorbitol is around 650 000 tons year-1.[52] Sorbitol is used in many fields, pharmaceuticals, foods, cosmetics, chemical industry, and is the starting material for the preparation of vitamin C. 

Iodo-desoxy derivatives of methylene, benzylidene and isopropylidene compounds have been transformed into their desoxy analogues with Raney nickel and hydrogen in basic media (e.g. hydroxides, methoxides and diethylamine). 0 47,60,81,82 Under similar conditions, l,3 2,4-diben-zylidene-5,6-sorbitoleen has been hydrogenated 8 and 2,4-benzylidene-6-nitro-6-desoxy-D-sorbitol has been converted into the corresponding amine.84 We are not aware of any report in this field of the removal of a benzylidene group by Raney nickel, as is the case with certain sugar derivatives.88... 

Approximately 1 p% of wild-type or mutant pCLI plasmid DNA is used for transformation of yeast cells. Spheroplasts of Saccharomyces cerevisiae strain GRF 18023,24 are prepared following the protocol of Burgers and Percival25 with some modification. High copy number transformants are directly selected on minimal medium plates lacking leucine and containing 8% glucose (to repress lysozyme expression) and 1 M sorbitol as an osmotic stabilizer. 

Willart, J., Lefebvre, J., Danede, F., Comini, S., Looten, E, and Descamps, M. (2005), Foly-morphic transformation of the G-form of d-sorbitol upon milling Structural and nano-structural analyses, Solid State Communi., 135(8), 519-524. 

Composition of electroporation buffer is an important factor affecting electroporation yields. Ionic strength of cell suspension medium needs control, which determines resistance of the cell suspension and resultant RC time constant of the field pulse. Medium supplemented with Ca and Mg in mM concentration range is found to promote efficiency of transformation and cell viability. Erythrocytes electroporated in isotonic buffer in the presence of EDTA or membrane specific drugs showed significant modification in hemolysis response to electroporation [33,34]. Use of square wave pulse removes the medium conductivity mediated effects on cell/tissue electroporation outcome. Generally, cells are pulsed in suspensions of sucrose, mannitol, or sorbitol. Electroporation as well as incubation of pulsed cells can be carried out in medium containing usual cell culture recipes. 

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