Activity of cytoplasmic N AD+- dependent dehydrogenases in the cotyledons of soaked Leguminous seeds

Abstract

The activity of three NAD+-dependent dehydrogenases: malic (MDH), alcohol (ADH), and lactic (LDH), were compared in seeds of seven species of Leguminous plants soaked for 24 hours. The total activity of three dehydrogenases varies at most about twice, while the ratio of activity of aerobic (MDH) to anaerobic (ADH + LDH) dehydrogenases varies about seven times. LDH activity was significantly lowest. The activity of the enzymes was thoroughly investigated in seeds of peas (Pisum sativum L.) and beans (Phaseolus vulgaris L.) soaked in aerated or nitrogenated water during 48 hours. Some differences in dehydrogenases activity in two species occurred, especially in MDH and ADH. In both specdes the activity of all enzymes under study was, after a certain time, always lower in the seeds soaked in nitrogenated than in those soaked in aerated water. Peas proved significantly more sensitive to the deficiency of oxygen than beans.