Ellagic acid recovery by solid state fermentation of pomegranate wastes

Solid state culture (SSC) fermentation has been applied to a variety of agrifood wastes for the recovery of bioactives.1,2In this study we comparatively investigated the recovery yields of ellagic acid (EA)by SSC fermentation of pomegranate husks by Aspergillus nigerand Saccharomyces cerevisiae.Material & Methods:Ultrasound/microwave-assisted extraction of fermented materials by A. niger and S. cerevisiaewas performed usingethanol/water (70/30). Extractions under different conditions as well as a hydrolytic treatment3were also carried out. Samples were analyzed by HPLC.Results: EA yields obtained by S. cerevisiaefermentation (4% w/w) were 5-fold higher than those by A. niger, with a 10-fold increase with respect to the unfermented materials.4Moreover, using DMSO as the solvent EA was obtained in 4% yields from S. cerevisiaefermented husks at a high purity degree. Hydrolytic treatment of S. cerevisiaefermented pomegranate husks afforded a material freed of the polysaccharide components that gave up to 12% w/w recovery yields of EA. Conclusion:The comparative analysis of the fermented extracts of pomegranate husks demonstratedthat SSC fermentation with S. cerevisiaeis a methodology with a great potential for the industrial recovery of EA,a highly valuable phenolic compound endowed with many bioactivities.