The Gas Requirements of Molds. IV. a Preliminary Interpretation of the Growth Rates of Four Common Mold Cultures on the Basis of Absorbed Gases

Abstract

With 4 common mold cultures, Aspergillus niger, A. flavus, Penicillium expansum, and Oospora lactis, grown on malt agar in various gas mixtures at different temps. and pressures, it is shown that growth is affected according to the gas laws as they govern the solubility of the gases in the medium or mycelium. The inhibiting effect of CO2 on the growth of these molds is in proportion to its solubility and not in proportion to the composition of the gas above the medium or mycelium. This has been shown to apply by changing either the temp. or the pressure of the gas above the organism during growth. It would appear that the O2 requirements of the molds might be affected in a similar way but this factor remains to be proved.