Efficient production of skimmin and 6′-succinylskimmin from umbelliferone by organic solvent-tolerant Bacillus licheniformis ZSP01 using nitrogen sources regulation strategy

An organic solvent-tolerant Bacillus licheniformis ZSP01 was newly isolated and utilized as a whole-cell biocatalyst for efficient production of skimmin and 6′-succinylskimmin from umbelliferone. Strikingly, the production of skimmin and 6′-succinylskimmin was significantly increased in the reaction media added with 10% dimethylsulfoxide (DMSO), and was separately regulated by adjusting the nitrogen sources in the fermentation medium. Efficient production of skimmin with a molar yield of 81% by resting cells of strain ZSP01 was achieved by using tryptone as nitrogen source for fermentation. Furthermore, efficient production of the novel compound, 6′-succinylskimmin, with a molar yield of 90% was obtained by using tryptone and yeast extract as a composite nitrogen source for fermentation. The glucosylation catalyzed by strain ZSP01 demonstrated an exquisite regioselectivity for a hydroxyl group at C-7 of the coumarin sheleton without neighboring substituents.

Graphical abstractAn efficient production of skimmin and a novel compound 6′-succinylskimmin, catalyzed by organic solvent-tolerant Bacillus licheniformis ZSP01, was successfully achieved using regulation strategy of nitrogen sources in media.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► An organic solvent-tolerant bacteria Bacillus licheniformis ZSP01 was isolated. ► This is the first report on coumarin derivatives biotransformation by bacteria. ► One of the products 6′-succinylskimmin is a novel compound. ► Nitrogen sources regulation strategy was used to achieve efficient production. ► Cheap sugar donor was used and substrate specificity was investigated.