A yeast co-culture-based biosensor for determination of waste water contamination levels

• Stability of two yeast co-cultures in a BOD sensor was studied.
• Substrate specificities of microbial co-culture-based receptor elements were assessed.
• New polymer for immobilization of NVP-modified PVA improved the characteristics.
• The co-culture of three strains provided for biosensor’s higher analytical signals.

Artificial microbial co-cultures were formed to develop the receptor element of a biosensor for assessment of biological oxygen demand (BOD). The co-cultures possessed broad substrate specificities and enabled assays of water and fermentation products within a broad BOD range (2.4–80 mg/dm3) with a high correlation to the standard method (R = 0.9988). The use of the co-cultures of the yeasts Pichia angusta, Arxula adeninivorans and Debaryomyces hansenii immobilized in N-vinylpyrrolidone-modified poly(vinyl alcohol) enabled developing a BOD biosensor possessing the characteristics not inferior to those in the known biosensors. The results are indicative of a potential of using these co-cultures as the receptor element base in prototype models of instruments for broad application.