The biochemical influence of m-alkoxyphenols on Saccharomyces cerevisiae cells was observed. When these chemicals have longer alkoxy groups-specifically, propoxy-, butoxy- and pentoxyphenol in concentrations of 2.0, 4.2, and 6.0 mM, respectively-they induce a decrease in oxygen consumption and heat production (produced by respiration), and an increase in NAD(P)H production by the microorganism. As a consequence, while the use of these alkoxyphenols in concentrations higher than 2.0 mM must be avoided in biotransformation reactions (for instance, in the study of Katsuobushi flavor), they can be used in pharmacological dosages against tumor cells. m-Alkoxyphenols that have shorter alkoxy groups (e.g., methoxyphenol and ethoxyphenol), caused no alteration in the biochemical metabolism of the cells tested in this study, even in concentrations of 6.0 mM.