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The agro-industries generate thousands of tons of by-products, such as cereal bran or sugar beet pulps, each year. For instance, in the Walloon Region, wheat transformation industry produces about 200,000 t of bran annually. Most of those by-products are, at best, used for cattle feeding. Through biocracking, this biomass may however constitute a renewable source for various value-added molecules of interest. These include dietary fiber, proteins, antioxidants, etc. The Feruzyme project focuses on ferulic acid, a major example of the hydroxycinnamic acids. These phenolic compounds show excellent antioxidant ability, and are found in relative abundance in cereal bran (about 6.6 mg.g-1, dry basis, in wheat bran). Ferulic acid (along with other hydroxycinnamic acids) is in majority (usually about 80%) ester-linked to other constitutive elements of the cell wall, namely arabinoxylans. Its enzymatic release depends mainly on the breaking of its ester linkage by Ferulic Acid Esterases (FAE, EC 3.1.1.73), which works in synergy with arabinoxylan-degrading enzymes (hemicellulase, including xylanase). Cellulase and even protease may also help by unweaving further the complex, cross-linked structure of bran cell-wall. The aim of our project is to design a process, starting from raw wheat bran to obtain purified ferulic acid, either crystallized or in concentrated solution. Furthermore, this process should be feasible at pilot scale, as it is meant to commercial application. Bran pre-treatment may impact the efficiency of the enzymatic action, by facilitating the access of the enzymes to their substrate (grinding, micronisation), or by modifying cell-wall structure (extrusion, steam-explosion, etc. processes involving non-enzymatic hydrolysis). The composition of the bran may also be altered, for instance by destarching, but also by pearling, this process being able to separate richer layers within the bran. Simpler process, like fine sieving of ground bran, is sufficient to eliminate part of the starch (wheat bran starch granules are usually about 20 µm). Purified FAE are still not commercially available. However, several enzyme complexes do present FAE activity: Depol™ 740 l (Biocatalysts), Pentopan™ 500 BG and Novo™ 188 (Novozymes), Pectinase™ PE (Catalysts), Grindamyl™ S100 (Danisco), etc. These complexes are used as filtration aid or for bread making. FAE activity is usually a side activity, the major being hemicellulase and cellulase, except for Depol™ 740 l in which FAE activity is standardized (36 U.g-1). Even though it should be preferably integrated in a wider industrial scheme, a high potential of wheat bran valorization lies in the field of natural antioxidants extraction.Natural green leaf volatiles (GLVs) are commonly sole AS aldehydic and alcoholic flavors; their synthesis is a great challenge for industry. Especially, the bioconversion step of fatty acid hydroperoxides into aldehydes by the hydroperoxide lyase (HL). This widely studied enzyme is present in cell membranes of green organs from superior plants. Extracted from its natural condition, HL is subject to a suicidal behavior, being irreversibly inhibited by its own substrate. Furthermore, GLVs produced are highly volatile and quickly degraded by other plant enzymes. Thence, high GLVs levels in industrial production are very difficult to obtain, but several biotechnological tools could be developed to enhance this natural synthesis level more than hundred times. This paper will describe a new method for GLVs production in bioreactor using sugar beet leaves as source of HL. One step reaction, including hydroperoxide metabolisation and GLVs extraction, is performed during a short time process. Downstream processing to dispose of natural and pure GLVs molecule will also be discussed.