Microorganism based biosensor for monitoring of microbiologically influenced corrosion caused by fungal species

Abstract

The microfungi are a group microorganisms, which obtain their energy either by aerobic oxidation or by anerobic fermentation of organic materials and release organic acid metabolite as end-product, which is corrosive in nature. The metabolites could be detected online by microbial biosensor. An amperometric microbial biosensor for the direct measurement of metabolites was developed on a modified oxygen electrode with immobilized <i>Acetobacter</i> sp. on acetylcellulose membrane. The sensor signal and response time were optimized with respect to pH, temperature, concentration and weight of the immobilized microbial cells. The best sensitivity and response time by microbial biosensor were obtained with 1,2 mg of microbial cells at 4.3 pH of the corrosive environment at room temperature (29^oC). The reproducibility of current and response time difference were examined, using the same corrosive environment.