Chemoenzymatic synthesis: a strategy to obtain xylitol monoesters

Abstract BACKGROUND: Fatty acid sugar esters are used as non‐ionic surfactants in cosmetics, foodstuffs and pharmaceuticals. In particular, monoesters of xylitol have attracted industrial interest due to their outstanding biological activities. In this work, xylitol monoesters were obtained by chemo...

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Bibliographic Details
Published in:Journal of Chemical Technology & Biotechnology
Main Authors: Rufino, Alessandra R., Biaggio, Francisco C., Santos, Júlio C., de Castro, Heizir F.
Format: Article in Journal/Newspaper
Language:English
Published: Wiley 2009
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Online Access:http://dx.doi.org/10.1002/jctb.2117
https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjctb.2117
https://onlinelibrary.wiley.com/doi/pdf/10.1002/jctb.2117
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Summary:Abstract BACKGROUND: Fatty acid sugar esters are used as non‐ionic surfactants in cosmetics, foodstuffs and pharmaceuticals. In particular, monoesters of xylitol have attracted industrial interest due to their outstanding biological activities. In this work, xylitol monoesters were obtained by chemoenzymatic synthesis, in which, first, xylitol was made soluble in organic solvent by chemo‐protecting reaction, followed by enzymatic esterification reaction using different acyl donors. A commercial immobilized Candida antartica lipase was used as catalyst, and reactions with pure xylitol were carried out to generate data for comparison. RESULTS: t ‐BuOH was found to be the most suitable solvent to carry out esterification reactions with both pure and protected xylitol. The highest yields were obtained for reactions carried out with pure xylitol, but in this case by‐products, such as di‐ and tri‐esters isomers were formed, which required a multi‐step purification process. For the systems with protected xylitol, conversions of 86%, 58% and 24% were achieved using oleic, lauric and butyric acids, respectively. The structures of the monoesters were confirmed by 13 C‐ and 1 H‐NMR and microanalysis. CONCLUSION: The chemoenzymatic synthesis of xylitol monoesters avoided laborious downstream processing when compared with reactions performed with pure xylitol. Monoesters production from protected xylitol was shown to be a practical, economical, and clean route for this process, allowing a simple separation, because there are no other products formed besides xylitol monoesters and residual xylitol. Copyright © 2009 Society of Chemical Industry