Biotransformation of procyanidins by a purified fungal dioxygenase : identification and characterization of the products using mass spectrometry Roopesh, K. Guyot, S. Sabu, A. Haridas, M. /Perraud Gaime, Isabelle /Roussos, Sevastianos /Augur, Christopher Procyanidins Aspergillus fumigatus Dioxygenase Purification Reversed-Phase High Performance Liquid Chromatography Electrospray Ionization-Mass Spectrometry Procyanidins commonly known as condensed tannins are a type of polyphenol with wide abundance naturally. They are commonly known as potent anti-oxidants with powerful free radical scavenging activity as well as anti-tumor-promoting activity. Little is known about the enzymatic mechanisms/pathways involved in the microbial biotransformation of these polyphenolic molecules. The extracellular enzyme, dioxygenase produced by Aspergillus fumigatus was used as in vitro tools to study the degradation pathway of a model procyanidin dimer, namely procyanidin B2. The enzyme was purified to homogeneity by a two step process of anion-exchange chromatography coupled with FPLC followed by gel-filtration chromatography coupled with HPLC and the molecular mass estimated. In addition, the different biotransformed products resulted from the dioxygenase action on P82 were purified using Reversed-Phase-High Performance Liquid Chromatography prior to their identification and characterization by structural elucidation using Electrospray Ionization-Mass Spectrometry. Subsequently, the mechanism of dioxygenase action on procyanidin dimer was defined. 2010 text https://www.documentation.ird.fr/hor/fdi:010049513 fdi:010049513 Roopesh K., Guyot S., Sabu A., Haridas M., Perraud Gaime Isabelle, Roussos Sevastianos, Augur Christopher. Biotransformation of procyanidins by a purified fungal dioxygenase : identification and characterization of the products using mass spectrometry. 2010, 45 (6), 904-913 EN