NOVEL BIOTRANSFORMATIONS OF AGROINDUSTRIAL CEREAL WASTE BY FERULIC ACID ESTERASES

With the yearly accumulation of agro-industrial waste-material generat ed by the milling, brewing and sugar industries in Europe, the importa nce of extracting high value residues must be considered to offset the cost of treating and disposing of the residues. This work reviews the identification, purification and characterisation of novel microbial esterases capable of releasing the bioactive phenolic compound, feruli c acid, from cereal cell-walls and agro-industrial waste. These phenol ic residues restrict the extent of hydrolysis of cell-wall carbohydrat es. Potential applications for the esterases in the food and pharmaceu tical industries are described. Enzymic removal of ferulic acid is ver y mild, allowing further treatment/processing of the residue and remov es the need for environmentally-unfriendly chemical clean-up processes . We now report the hydrolysis, on a laboratory scale, of wheat bran ( 1 kg) by a Trichoderma xylanase preparation and an Aspergillus niger f erulic acid esterase (FAE-III) to produce free ferulic acid (5.7 g). ( C) 1997 Elsevier Science B.V.