Solid state fermentation of olive mill residues by wood- and dung-dwelling Agaricomycetes: effects on peroxidase production, biomass development and phenol phytotoxicity.
The in vivo conversion of dry olive mill residue (DOR) by wood- and dung-dwelling fungi - Auricularia auricula-judae, Bjerkandera adusta and Coprinellus radians - increases peroxidase secretion up to 3.2-3.5-fold (∼1.3, 3.5 and 7.0 Ug(-1) DOR for dye-decolorizing peroxidase, manganese peroxidase and aromatic peroxygenases, respectively). The incubation of DOR with these fungi produced a sharp decrease in total phenolic content (100% within 4 wk), a reduction in phytotoxicity as well as a certain degree of plant growth caused by the stimulating effect of fungal-treated DOR. These findings correlate with a characteristic shift in the fragmentation pattern of water-soluble aromatics (detected at 280 nm) from low (0.2, 1.5 and 2.2 kDa, respectively) to high molecular mass (35 to >200 kDa), which demonstrates the presence of a polymerization process. Phenol-rich agricultural residues are a useful tool for enzyme expression and production studies of peroxidase-producing Agaricomycetes which could make DOR a valuable organic fertilizer.
Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), Prof. Albareda 1, E-18008 Granada, Spain.
Rocío
R
Reina
Christiane
C
Liers
Juan Antonio
JA
Ocampo
Inmaculada
I
García-Romera
Elisabet
E
Aranda
D001487:Basidiomycota / Q000502:physiology*; D001673:Biodegradation, Environmental; D005285:Fermentation; D019649:Food Industry; D007220:Industrial Waste / Q000032:analysis*; D031658:Olea; D009195:Peroxidase / Q000378:metabolism*; D019800:Phenol / Q000032:analysis* / Q000378:metabolism; D014865:Waste Disposal, Fluid / Q000379:methods*; D014934:Wood
D007220:Industrial Waste; D019800:Phenol; D009195:Peroxidase
Agaricomycetes; Aromatic peroxygenase; Dry olive mill residue; DyP-type peroxidase; Phenols