In the present study characterization of carotenoids from selected strains of Streptomyces sp. of Tendania anhelan, Epinephelus diacanthus and Cyprinus carpio, and Osepherenemous gourami were observed. The interaction of microbes particularly Streptomyces sp. in the gut and sponges of fishes in two environmental biotopes and their ability of producing carotenoids were assessed. The UV spectrum, TLC and HPLC results showed the biosynthesis of carotenoids in various strains of Streptomyces sp., clearly indicate the presence of phytoene, phytofluene, α-carotene, β- carotene and β-isorenieratene. Carotenoids are also important due to their potential antitumor properties and because they are used as colorants in the food industry to pigment salmon, trout and poultry flesh, or to intensify the colour of egg yolk. These pigments are not essential for other carotene containing microorganisms, as is the case for fungi but they are indeed very important due to their ability to act as antioxidant agents.