Effect of a magnetic field on an aereated Saccharomyces cerevisiae culture

The growth of a Saccharomyces cerevisiae culture in cane molasses was evaluated under the action of a variable magnetic field (MF) of high frequency and very low flux density. Cultures growing tinder MF action were compared against cultures in normal environment (control). Tests were performed in 400ml reactors at 25 degrees C. The air flux in the reactors was approximately 1 vvm. A 100kHz MF of 250mG was applied for 200s. Results show that the MF can stimulated culture growth with and without aeration and that there is a limit for the stimulation over which growing inhibition appears. Under certain conditions, the culture presents a sort of adaptation to the MF action and the yeast can overcome the inhibition. It was noticed that MF affects substrate consumption, which means that under certain conditions MF treated micro-organisms can make better use of the substrate. Culture aeration interacts with the MF effect on growth and substrate consumption. After application on a single MF treatment to the yeast culture, it was noticed that after 25h the culture showed a 14.4% growth increment compared to the control. Also, substrate consumption by the treated culture was lower than in the control culture.