Fig. 4

β-ionone flask fermentation optimization. a β-ionone production in strain YLBI3118 cultivated in YP media containing 20 g/L of different carbon sources. b β-ionone yield in strain YLBI3118 cultured in media containing different carbon/nitrogen ratios. YPDm, modified YPD medium: 3% glucose, 1% peptone, 0.5% yeast extract. c β-ionone production in strain YLBI3118 cultured in different nitrogen sources (20 g/L peptone or tryptone) medium. Data represent the mean ± standard deviation (n = 3). Significance was marked by t-test, *p-value ≤ 0.05; **p-value ≤ 0.01; ***p-value ≤ 0.001