Development, Investigation of Parameters and Estimation of Possibility of Adaptation of Pichia angusta Based Microbial Sensor for Ethanol Detection

Abstract

The analytical parameters of recognizing element of a biosensor for ethanol detection have been estimated in three wild type strains of Pichia angusta. The possibility of increasing sensor selectivity through induction and inhibition of intracellular enzymes in the course of biomass cultivation has been studied. A biosensor based on the cells of strain P. angusta VKM Y‐2518 grown on 1% methanol proved to be the most prospective for ethanol detection. This sensor was insensitive to carbohydrates and organic acids; the interfering compound at ethanol detection was methanol. The lower limit of ethanol detection was 0.012 mM. The optimum of sensor response dependence on pH and ion force of the buffer solution was in the range of pH 7.2–7.6 and around 30 mM, respectively. Indications of the sensor were stable for 5 days. The stability of cells was studied at storage as wet centrifuged biomass at 4°C and in immobilized state at 20, 4, and −10°C. The storage of centrifuged cells at 4°C proved to be optimal. The sensor based on P. angusta VKM Y‐2518 was used for ethanol detection in alcoholic beverage; besides, it can be used for ethanol detection in biological fluids and at optimization of enzymatic processes.

Keywords:

• Biosensor
• methylotrophic yeast
• detection of alcohols

The authors are grateful to I. A. Toropova, a collaborator from the Laboratory of Biosensors, Institute of Biochemistry and Physiology of Microorgnaisms RAS, for providing the enzyme preparation of alcohol oxidase isolated from the cells of H. polymorpha NCYC 495 ln.