title: Inactivation, lysis and degradation by-products of Saccharomyces cerevisiae by electrooxidation using DSA.
abstract: The yeast Saccharomyces cerevisiae, a microorganism with cell walls resistant to many types of treatments, was chosen as a model to study electrochemical disinfection process using dimensionally stable anodes (DSA). DSA electrodes with nominal composition of Ti/RuO2TiO2and Ti/RuO2TiO2IrO2were evaluated in 0.05 mol L-1Na2SO4containing yeast. The results showed inactivation about of 100 % of the microorganisms at Ti/RuO2TiO2by applying 20 and 60 mA cm-2after 120 min of electrolysis, while a complete inactivation at Ti/RuO2IrO2TiO2electrode was achieved after 180 min at 60 mA cm-2. When chloride ions were added in the electrolyte solution, 100 % of the yeast was inactivated at 20 mA cm-2after 120 min of electrolysis, independent of the anode used. In the absence of chloride, the energy consumption (EC) was of 34.80 kWh m-3, at 20 mA cm-2by using Ti/RuO2TiO2anode. Meanwhile, in the presence of chloride, EC was reduced, requiring 30.24 and 30.99 kWh m-3at 20 mA cm-2, for Ti/RuO2TiO2and Ti/RuO2IrO2TiO2electrodes, respectively, The best performance for cell lysis was obtained in the presence of chloride with EC of 88.80 kWh m-3(Ti/RuO2TiO2) and 91.85 kWh m-3(Ti/RuO2IrO2TiO2) to remove, respectively, 92 and 95 % of density yeast. The results clearly showed that yeast, as a model adopted, was efficiently inactivated and lysed by electrolysis disinfection using DSA-type electrodes.
authors: Faculty of Natural and Exact Sciences, University of State of Rio Grande do Norte, CP 70, CEP 59625-620, Mossoró, RN, Brazil.
authors: Lyliane F
authors: LF
authors: Trigueiro
authors: Faculty of Natural and Exact Sciences, University of State of Rio Grande do Norte, CP 70, CEP 59625-620, Mossoró, RN, Brazil.
authors: Larissa M
authors: LM
authors: Silva
authors: Faculty of Natural and Exact Sciences, University of State of Rio Grande do Norte, CP 70, CEP 59625-620, Mossoró, RN, Brazil.
authors: Luciana A B D
authors: LABD
authors: Itto
authors: Faculty of Natural and Exact Sciences, University of State of Rio Grande do Norte, CP 70, CEP 59625-620, Mossoró, RN, Brazil.
authors: Thiago M B F
authors: TMBF
authors: Oliveira
authors: São Carlos Institute of Chemistry, University of São Paulo, Avenida Trabalhador São Carlense 400, CEP 13566-590, São Carlos, SP, Brazil.
authors: Artur J
authors: AJ
authors: Motheo
authors: Institute of Chemistry, Federal University of Rio Grande do Norte, Campus Universitário s/n, CEP 59078-970, Natal, RN, Brazil.
authors: Carlos A
authors: CA
authors: Martínez-Huitle
authors: Faculty of Natural and Exact Sciences, University of State of Rio Grande do Norte, CP 70, CEP 59625-620, Mossoró, RN, Brazil.
authors: Janete J F
authors: JJF
authors: Alves
authors: Faculty of Natural and Exact Sciences, University of State of Rio Grande do Norte, CP 70, CEP 59625-620, Mossoró, RN, Brazil. suelycastro@uern.br.
authors: Suely S L
authors: SSL
authors: Castro
mesh_terms: D004203:Disinfection / Q000379:methods*; D004572:Electrolysis / Q000379:methods*; D010084:Oxidation-Reduction; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D014874:Water Pollutants, Chemical
keywords: DSA; Electrochemical treatment; Electrooxidation; Microorganism inactivation; Saccharomyces cerevisiae; Water disinfection