Exploring algae and purple bacteria: Isolation, characterization and their application in futuristic greener technologies

Abstract

Photosynthetic microorganisms, both oxygenic and anoxygenic, can be isolated from a wide variety of normal and extreme environments. Isolation of these microbes can differ according to the organism and can include selective media and incubation conditions

for example, removal of Si and N for preventing diatoms and isolating nitrogen fixers, respectively. Photosynthesizers like algae and purple sulfur bacteria are an important part of the ecosystem as pollution mitigators and as sources of high-value cosmetics, food supplements, nutraceuticals, and pharmaceuticals. Some of the high-value compounds include carotenoids, γ-butyric acid, polyhydroxyalkanoates, polyphenols, sterols, vitamins, and minerals. This chapter focuses on the conventional and advanced isolation techniques for these common photosynthesizers. The methodologies for their characterization using analytical instruments under natural and stressful environments are also discussed. It also elaborates on the application of such algae and bacteria for simultaneous waste valorization under varying stress conditions and also on the applications of these microbes for greener production of high-value compounds, for efficient replacement of fossil-fuel-derived alternatives. © 2025 Elsevier B.V., All rights reserved.