Dynamics of electrical resistance of kombucha zoogleal mats

Abstract

We demonstrated that zoogleal mats of kombucha exhibit spikes of electrical resistance. A kombucha is a sugared tea fermented by a symbiotic community of over twenty species of bacteria and yeasts which produce cellulosic gelatinous zoogleal mats. We recorded electrical resistance of the zoogleal mats via platinum electrodes placed at a distance one centimetre of each other. We found that the mats show temporal variations in electrical resistance in a range 0.13 MOhm to 0.19 MOhm. We discovered spikes of the mats resistance morphologically similar to action potential spikes. Average duration of a resistance spike is 1.8 min, average amplitude is 2.2 kOhm. Average interval between resistance spikes is c. 20 min. The discovered resistive spiking of kombucha mats might indicate on their memfractive properties, and thus open pathways towards prototyping neuromorphic devices with living zoogleal mats.