Removal of Monomeric Phenols in Dry Mill Olive Residue by Saprobic Fungi

Abstract

The dry olive residue (DOR) obtained from the olive oil extraction process has toxic components against plants and microorganism growth, particularly monomeric phenols. In this investigation nine saprobic fungi were found to be capable of completely removing these phenols from the solid after 20 weeks of growth, although the rate depended on the type of fungi and phenol. Results showed that most of the fungi tested first eliminated o-diphenols and then non-o-diphenols. However, some fungi did not follow this trend. Phanerochaete chrysosporium first removed hydroxytyrosol and tyrosol and later their glucosides and, in contrast, Paecylomyces farinosus hydrolyzed hydroxytyrosol and tyrosol glucosides at the first stage, 2 weeks of growth, and then eliminated all monomeric phenols. The behavior of this fungus seems of great interest for recovering phenolic antioxidants from the DOR. Similarly, differences in DOR decolorization capacity among the fungi tested were also observed. Coriolopsis rigida showed the highest capacity, followed by Phebia radiata, Pycnoporus cinnabarinus, and Pha. chrysosporium. Therefore, both decolorization and monomeric phenol elimination pointed out that saprobic fungi could be used to detoxify the DOR obtained from the two-phase system of the olive oil extraction process.

Valorization of olive oil solid waste using high pressure–high temperature reactor

“…In the past decade, several researchers have studied the presence of contaminants (pesticides) in the pomace (Albarran, Celis, Hermosin, Lopez-Pineiro, & Cornejo, 2004), the detoxification of this residue by the use of microorganisms (Sampedro, Romero, Ocampo, Brenes, & Garcia, 2004) or the reuse of olive pomace as metal ion adsorbent (Pagnanelli, Toro, & Veglio, 2002).…”

Integrated biovalorization of wine and olive mill by-products to produce enzymes of industrial interest and soil amendments

“…Samples (0.5 g) were extracted with methanol/water according to the method described by Sampedro et al (2004). Phenols in DOR and GPS were analyzed by ultra performance liquid chromatography-mass spectrometry (Acquity UPLC System, Waters) by the Scientific Instrumentation Centre of the University of Granada (CIC, Granada, Spain) using a Waters ACQUITY UPLC™ HSS T3 column (2.1 × 100 mm, 1.8 µm).…”

Selection of non-conventional yeasts and their use in immobilized form for the bioremediation of olive oil mill wastewaters

“…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).…”