Anaerobic degradation of organic compounds in hypersaiine environments: Possibilities and limitations

Anaerobic digestion has long been a well-established procedure for the disposal of organic waste material. Theoretically, total conversion of most organic substrates, even relatively complex ones, to carbon dioxide and methane is possible under anaerobic conditions, the methane being an economically important by-product of the process. Little is known as to the extent of anaerobic degradation of organic matter in hypersaline environments. The sediments of hypersaline water bodies are generally anaerobic, partly as a result of biological activity in the sediment and the overlaying water, and also because of the limited solubility of oxygen in hypersaline brines. Anaerobic degradation of complex organic substrates to carbon dioxide and methane is never achieved by one microorganism alone, but requires the cooperation of a variety of bacteria, performing different steps of the process, and as certain steps in the degradation can proceed only concomitantly with others, the different processes are closely interdependent.