Induction of liquid bacterial and solid fungal cultures by conductive electrostimulation

Abstract When testing cultures of microorganisms under electrostimulation to explore antimicrobial use for therapy and pasteurization, small, diverse windows of stimulative effects have been noticed. This work strives to explore possible stimulative effects of conductive electrostimulation with alternating current on fungi and bacteria as a proof-of-principle applicable to production of biomass, probiotics, biopharmaceuticals, bacteriotherapeutics, metabolites and other bioproducts or bioprossesses. To do so an iontophoresis device was applied in solid fungal cultures and presentation of mycelial diameter compared to control dishes in growth-time curves; and in liquid bacterial cultures without or with simultaneous or consecutive pasteurization and estimation of the colony forming units after a set time, in comparison with proper controls. Six fungi belonging in four divisions showed conditional stimulative effects when tested in solid cultures. Six bacteria in respective liquid cultures and of different shapes and Gram status also showed, under different conditions, stimulative effects with Electrostimulation if treated solely and alleviating effects if co-treated with mild heat pasteurization protocols. There is no uniform set of parameters for stimulative results of electrostimulation; though it seems that some nutrient substrates are more supportive to stimulative effects compared to others.