Simultaneous utilization of heterotrophic substrates by Hansenula polymorpha MH30 results in enhanced growth rates

Summary

The maximum specific growth rate (μ_max) of Hansenula polymorpha MH30 on xylose as the sole source of carbon and energy is 0.175 h⁻¹, on methanol 0.21 h⁻¹, on glycerol 0.27 h⁻¹ and on glucose 0.61 h⁻¹. On mixtures of xylose plus methanol, xylose plus glycerol, xylose plus glucose and glycerol plus glucose H. polymorpha MH30 grows faster: 0.36 h⁻¹, 0.37 h⁻¹, 0.47 h⁻¹ and 0.52 h⁻¹, respectively. Attempts have been made to explain these somewhat surprising results, especially the fact that the growth rates on xylose plus methanol and xylose plus glycerol exceed the specific growth rates of these on even the “faster” partner in the mixture.