Mediated microbial biosensor using a novel yeast strain for wastewater BOD measurement

• Published in: Applied microbiology and biotechnology 2001-08, Vol.56 (3/4), p.550-554
• Main Authors: Trosok, S.P, Driscoll, B.T, Luong, J.H.T
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Biochemical Oxygen Demand; Biological and medical sciences; Biosensing Techniques - methods; Biosensors; Biotechnology; Cells, Immobilized; Culture Media; detection limit; Electrodes; Electrons; enzymes; Ferricyanides - metabolism; Fundamental and applied biological sciences. Psychology; glassy carbon electrode; glucose; glutamic acid; Industrial wastewater; Methods. Procedures. Technologies; Oxygen Consumption; pulp and paper mill effluents; Pulp wastes; Reproducibility of Results; Sensitivity and Specificity; Various methods and equipments; Waste Disposal, Fluid; wastewater; Water Microbiology; Yeasts; Yeasts - cytology; Yeasts - growth & development; Yeasts - isolation & purification
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s002530100674

Two new yeast strains (SPT1 and SPT2) were isolated and immobilized on glassy carbon electrodes to form microbial biosensors for estimation of biochemical oxygen demand (BOD). Ferricyanide was proven to be the most efficient mediator to shuttle electrons from the redox center of reduced microbial enzymes to the electrode in the presence of excess glucose/glutamic acid (GGA). With a 3-fold greater metabolic assimilation capability and greater responses to various effluent samples, SPT1 was selected for sensor-BOD measurements. BOD estimations for the GGA standard resulted in an extended linear range: 2-100 mg/l. Response reproducibility was +/-10% for a GGA standard containing 10 mg BOD/l. For analysis of pulp mill effluents, the BOD detection limit was 2 mg/l with a response time of 5 min.