Biotransformation of halogenated 2′-deoxyribosides by immobilized lactic acid bacteria

An efficient and green bioprocess is herein reported to obtain halogenated nucleosides by transglycosylation using immobilized lactic acid bacteria (LAB). Lactobacillus animalis ATCC 35046 showed a yield of 95% at 0.5 h to synthesize 5-fluorouracil-2′-deoxyriboside (floxuridine). Calcium alginate was the best matrix for whole-cell immobilization by entrapment. Its productivity was 87 mg/L h in a continuous bioprocess. When adsorption techniques were evaluated, DEAE-Sepharose was the support which showed higher microbial load, its productivity being 53 mg/L h. Additionally, this microorganism was able to produce 5-bromouracil-2′-deoxyriboside, 6-chloropurine-2′-deoxyriboside and 6-bromopurine-2′-deoxyriboside.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► An efficient bioprocess is herein reported to obtain halogenated 2′-deoxyribosides. ► L. animalis ATCC 35046 showed 95% yield at 0.5 h to synthesize floxuridine. ► Two laboratory-scale bioprocesses are reported.