title: Pleurotus ostreatus biofilms exhibit higher tolerance to toxicants than free-floating counterparts.
abstract: The MBEC(TM)-High Throughput Assay based on the Calgary Biofilm Device was used to produce and to characterize Pleurotus ostreatus biofilms. Hydroxyapatite coating of pegs was required to enable biofilm attachment; biofilm amounts and homogeneity of distribution were markedly improved upon removal of non-sessile biomass after 48 h from inoculation. Scanning electron microscopy showed surface-associated and multi-layered growth stabilized by the presence of an extracellular matrix (ECM). Biofilms had higher contents of total sugars and ECM than their free-floating counterparts. Tolerance to Cr(VI) in the former was about twice that of the latter as inferred by the respective inhibitory concentrations (48.4 vs 24.1 mM and 114.5 vs 61.0 mM in 4- and 7-d-old cultures, respectively). Biofilms also displayed superior olive-mill wastewater (OMW) treatment efficiency along 5 consecutive batches leading to chemical oxygen demand and total phenol removals higher than 50 and 90%, respectively. Laccase activity peaks in biofilm cultures grown on OMW were significantly higher than those in free-floating cultures.
authors.affiliation: a Department for Innovation in Biological, Agro-Food and Forest Systems , University of Tuscia , Viterbo , Italy .
authors.forename: Lorena
authors.initials: L
authors.lastname: Pesciaroli
authors.forename: Maurizio
authors.initials: M
authors.lastname: Petruccioli
authors.forename: Federico
authors.initials: F
authors.lastname: Federici
authors.forename: Alessandro
authors.initials: A
authors.lastname: D'Annibale
mesh_terms: D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D002857:Chromium / Q000633:toxicity*; D017608:Chromium Compounds / Q000633:toxicity; D017886:Durapatite / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism; D042845:Laccase / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D008855:Microscopy, Electron, Scanning; D000069463:Olive Oil; D010933:Plankton / Q000187:drug effects / Q000502:physiology; D010938:Plant Oils / Q000378:metabolism*; D020076:Pleurotus / Q000187:drug effects* / Q000502:physiology* / Q000648:ultrastructure; D013045:Species Specificity; D013997:Time Factors; D014865:Waste Disposal, Fluid; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D017608:Chromium Compounds; D000069463:Olive Oil; D010938:Plant Oils; D014874:Water Pollutants, Chemical; D002857:Chromium; C074702:chromium hexavalent ion; D017886:Durapatite; D042845:Laccase