Change in specific growth rates through supplementation of amino acids. The relative specific growth rate, i.e., specific growth rate in the presence the amino acid supplementation divided by that in the absence of the supplementation, are presented. (a) isoleucine supplementation in a final concentration of 0.1 mM; (b) tryptophan and (c) histidine supplementation in a final concentration of 1 mM are plotted for the cases of strain P and A with and without the ethanol stress addition. The error bars represent the standard deviation from 3 replicate measurements. An asterisk indicates a P-value of < 0.02, two asterisks indicate a P-value of < 0.002, respectively, determined by t-test.