Correlation between free and conjugated amino acids in some marine algae during their vegetative growth and reproductive stages

Abstract

Although descriptive studies have elucidated details of the life cycles of a great 9 variety of algal species, the physiology of most of the functional stages involved remains completely obscure (ERBEN, 1962). At present no generalization on the basic factors controlling the phenomena of sporulation can be more than speculative. KLEBS (1928) and NEEB (1952) have concluded that sporulation in a given species of algae is induced by one specific system within the cell which controls spore formation. As stated by MOHSEN et al. (1974) the majority of investigations on the proteins, peptides and free amino acid contents of marine algae have been based on the analysis of species collected at any stage of their growth. However, periodic analysis of the proteins and amino acid contents of some algae have been made (HASS, HILL and KARSTENS, 1935; COULSON, 1953; OGINO, 1955; PILLAI, 1957; FOWDEN, 1962; NASR and BEKHEET, 1967). The aim of this work is to study any differences which might exist between the concentration of free and conjugated amino acids during vegetative and reproductive stages of the life histories of some algae. The algae chosen for this study were Laurencia papillosa (Rhodophyceae),Cystoseira barbata (Phaeophyceae) and Enteromorpha intestinalis (Chlorophyceae). These algae differ from one another by the nature of their reproductive stages and type of the life cycle. Consequently, the growth and reproduction in these algae may be sensitive to environmental factors.