Biosensor based on fermentation activity of yeast

Activity of microorganisms depends on several factors, among them -- the quality of water, various emissions, strains of microorganisms, deviations in metabolic processes, etc. Favorable conditions stimulate activities, whereas pathogenic conditions inhibit them. A significant advantage of microorganisms as a biosensor is a high sensitivity, detection of nonspecific stimulants/pathogens that exert a complex effect on metabolism, low cost and rapidity of tests. To measure the activity of microorganisms, the ethanol fermentation of 'Baker's yeast' (Saccharomyces cerevisiae) is used, where a glucose is converted into ethanol and carbon dioxide. The amount of produced CO2 depends on the yeast activity, which in turn is detected as a varyation ionic content in the reagent containers. The recognition of nonspecific stimulation/pathogenicity is based on accurate electrochemical measurements by comparing control and experimental populations.

Description of the device. The device represents a differential EIS measuring system with 100ml containers. Since the fermentation depends on temperature, the reagent chambers have a built-in thermostat, which maintains a constant temperature. Alcohol fermentation is carried out in conventional containenrs with temperature sensors. To prevent the effect of biophotonic transfer between populations, all containers are separated from each other. The device is connected to the MU3.4 measurement module that it communicate with PC via USB interface. Graphs are plotted automatically. One measurement lasts about 120-180 minutes; only yeast, sugar, water and the measuring device are needed for the test.

Measured phenomena and effects. This system allows performing the following measurements:

  1. Determining the quality of drinking or industrial water, also in the food industry; the detection of biological effects of 'activated water'. Specific feature of this approach is the detection of small concentrations of nonspecific pathogens at early stages before performing specific bio-chemical tests.
  2. Detection and measurement of infoceutical effects in terms of 'stimulation' -- 'inhibition'; detection of biological effects from various 'info devices'. A rapid accumulation of statistically significant number of measurements is possible.
  3. Detecting and measuring biological effects of weak emissions, including EM fields, magnetic and laser treatment of materials, geo-biological (pathogenic) effects and non-electromagnetic emissions from various artificial and natural sources.

Infoceutical production. The software and hardware of this device are adapted for performing laboratory and industrial measurements in areas of infoceutical production and highly diluted solutions. CYBRES provides additional equipment for such tests and offers specific demonstration programs.

Complementarity to electrochemical measurements. The EIS spectrometer and Biosensor are complementary to each other: EIS approach allows determining the presence of emissions ('activation'), whereas the Biosensor detects nonspecific biological effects. Combination of both approaches enables increasing the reliability of measurements by well accepted physicochemical and biological techniques.

Bio-hybrid systems research. It provides biopotential, electrochemical, thermal and optical interfaces to fluidic solutions (2x 100ml) of yeast/algae (or other microorganisms). Another flat version, like Petri dish, with increased number of electrodes for better intractability with populations is possible. This system is an interfacing tool for handling microorganisms on a population level, exploring feedback mechanisms, analysing sensing and actuating capability of microorganisms, involving e.g. artificial evolution for real-world bio-hybrid systems or other scientific issues.