Production of Antioxidant Nutraceuticals by Solid-State Cultures of Pomegranate (Punica granatum) Peel and Creosote Bush (Larrea tridentata) Leaves

In this work, creosote bush (Larrea tridentata) leaves and pomegranate (Punica granatum) peels were characterized for their use as a source of antioxidants and a support in solid-state fermentation. This work focuses on the kinetic evaluation of physicochemical changes during the fungal fermentation of two tannin-rich plant materials, mainly on the polyphenolic content. Aspergillus niger GH1 was used in the fermentation processes, the cultures were monitored for 96 h. The content of proteins, crude fibres, lipids, reducing and total sugars was evaluated following the AOAC methods. Tannins were analyzed using a spectrophometric method. Biodegradation of ellagitannins was monitored kinetically and the accumulation of gallic and ellagic acids was determined by HPLC. Results demonstrated that pomegranate peel and creosote bush leaves are excellent supports for solid-state fermentation and sources of antioxidants.