title: The effect of spent bleaching earth ageing process on its physicochemical and microbial composition and its potential use as a source of fatty acids and triterpenes.
abstract: This study was aimed at investigating the physicochemical and microbiological changes that took place during the ageing process of spent bleaching earth in the presence of autochthonous microorganisms. Research material included fresh spent bleaching earth (SBE0) and the same material after 3 years of storage at the constant temperature of 20 °C, without aeration and moistening (SBE3). Changes in the chemical composition of analysed waste material were observed during its ageing process point to a spontaneous bioconversion of fat substance towards formation and/or release of free saturated fatty acids C16:0 and C18:0 (14.3 g 100 g(-1) D.M.), triterpenes (8.48 g 100 g(-1) D.M.), cholesterol (3.29 g 100 g(-1) D.M.), small quantities of carbohydrates and esters (0.80 g 100 g(-1) D.M.). This process was accompanied by other changes in physicochemical parameters of the waste material, such as colour, odour and viscosity, decrease in fat content from 28.27 to 24.6 % and that of soluble forms of metals (Mo, Cu, Fe, Zn, Ni, Cr and Mn), ranging from 25 to 75 %, and an increase in pH, from 3.85 to 4.2. At the same time, changes in the microbial consortium were observed.
authors.affiliation: Department of Biotechnology and Molecular Biology, Faculty of Natural and Technical Sciences, University of Opole, Kard. B. Kominka 6a, 45-035, Opole, Poland.
authors.forename: Teresa
authors.initials: T
authors.lastname: Krzyśko-Łupicka
authors.forename: Krystyna
authors.initials: K
authors.lastname: Cybulska
authors.forename: Andrzej
authors.initials: A
authors.lastname: Wieczorek
authors.forename: Ewa
authors.initials: E
authors.lastname: Możdżer
authors.forename: Maciej J
authors.initials: MJ
authors.lastname: Nowak
mesh_terms: D001673:Biodegradation, Environmental; D005227:Fatty Acids / Q000032:analysis / Q000737:chemistry*; D005229:Fatty Acids, Monounsaturated; D006863:Hydrogen-Ion Concentration; D019216:Metals, Heavy / Q000032:analysis; D059013:Microbial Consortia; D010938:Plant Oils / Q000737:chemistry; D011044:Poland; D000074262:Rapeseed Oil; D012037:Refuse Disposal / Q000379:methods*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry*; D013696:Temperature; D013997:Time Factors; D014315:Triterpenes / Q000032:analysis / Q000737:chemistry*; D014866:Waste Products
chemical_list: D005227:Fatty Acids; D005229:Fatty Acids, Monounsaturated; D019216:Metals, Heavy; D010938:Plant Oils; D000074262:Rapeseed Oil; D012989:Soil Pollutants; D014315:Triterpenes; D014866:Waste Products