REDUCING ACTIVITY AND THE FORMATION OF BASE IN THE CORALLINE ALGAE - ELECTROCHEMICAL MODEL

Processes postulated to occur in the calcification of Clathromorphum and Corallina have been investigated. These calcified algae have been found to exhibit strong oxidase, catalase and carbonic anhydrase activity. The thallus is normally reducing and it is shown that oxidation of this reducing activity by air, oxygen or hydrogen peroxide leads to an increase of alkalinity by the removal of hydrogen ions. It is suggested that such action occurs in the normal living alga. The principle by which calcification may be brought about by the production of an alkaline region within the thallus and an acidic region at the surface, so that there is a net loss of acid by diffusion into the sea, is illustrated by a simple model consisting of two platinum electrodes, which calcifies in a similar way. Attention is drawn to the fundamental similarities between the processes leading to calcification in the alga, the electrode model and the events in corroding steel. Such comparison stresses the necessity for both chemical and spatial separation of acid and base if calcification is to occur by such a method. © 1979, Marine Biological Association of the United Kingdom. All rights reserved.