“…OMW need to be treated before their use because of their phytotoxic and antimicrobial effects, which are related to a number of different factors, such as the presence of phenolic compounds, organic volatile acids, acidic pH and the high level of salts such as potassium (Paredes et al, 1999). Different approaches have been developed for OMW biological treatment, such as anaerobic digestion (Rincón et al, 2006), natural biodegradation in evaporation ponds (Buyer et al, 1999), removal of phenols by means of saprophytic fungi (Sampedro et al, 2004), as well as by using bacteria, such as Ralstonia sp. and Pseudomonas putida (Di Gioia et al, 2001), biodegradation by composting with agricultural wastes (Paredes et al, 2002), vermicomposting and the production of metal-binding microbial exopolysaccharides (Morillo et al, 2006).…”