An Insight into the Prevalence and Enzymatic Abatement of Urethane in Fermented Beverages

  • Bidyut R. Mohapatra


Urethane, also known as ethyl carbamate (NH2COOC2H5), is generally formed in fermented products, especially in alcoholic beverages, during the process of fermentation, distillation and/or long term storage at room temperature. In recent years, urethane has been classified as a Group 2A (probably carcinogenic to humans) compound by the International Agency for Research on Cancer (IARC). This reclassification of urethane brings attention of global regulatory agencies to reduce its concentration in alcoholic beverages via the development of green and cost-effective methods. Urethanase, which directly hydrolyzes urethane into ethanol, carbon dioxide and ammonia, has industrial potential for enzymatic removal of this carcinogen. This chapter provides an overview of the mechanisms involved in the formation of urethane in fermented beverages, and methods that have been recommended for urethane abatement. Additionally, the potential of microbial urethanase is discussed by reporting the comparative biocatalytic characteristics of free and chitosan nanoparticles immobilized urethanase of a novel bacterial strain Exiguobacterium species Alg-S5 (GenBank accession number KY009691) isolated from decomposed Sargassum seaweed off the coast of Barbados.


Exiguobacterium Chitosan Immobilization Nanoparticles Urethanase Urethane 



The author thanks Dr. Orville Roachford for useful advice. This research was partly supported by the UWI Campus Research Award Fund.


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© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.Department of Biological and Chemical SciencesThe University of the West Indies, Cave Hill CampusBridgetownBarbados

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