Effect of Carbon Dioxide on the Manganese Absorption of Red Beet Tissue

Abstract

IN an earlier publication¹ the discovery was reported of a substance extractable by water from red beetroot and capable of inhibiting the active accumulation of manganese by slices of storage tissue. It was suspected at the time that the substance might be produced by the dark fixation of respiratory carbon dioxide which, as Burton² showed for potatoes, may reach concentrations of about 7 per cent in bulky storage organs. I have now shown that the presence of carbon dioxide in solutions from which beetroot tissue slices are absorbing manganese reduces the rate of absorption. The reduction in rate is proportional to the concentration of carbon dioxide up to about 40 per cent, at which the rate appears to be minimal.