Prospects of cyanobacterial pigment production: Biotechnological potential and optimization strategies

Increasing awareness of the harmful effects of synthetic colorants has led consumers to favor the use of natural alternatives such as plant or microbial pigments in food and cosmetics. Cyanobacteria are a rich source of many natural biopigments that are of high commercial value. In the market, bio-based pigments are usually sold as extracts to reduce purification costs. Various cell disruption methods are used for pigment extraction, such as sonication, homogenization, high pressure, supercritical CO₂ extraction, enzymatic extraction, as well as other promising novel extraction methods that make the production of cyanobacterial pigments economically viable. In addition, a continuous cultivation system is considered the most suitable cultivation mode for large-scale biomass production. However, a major limitation in the large-scale production of cyanobacterial pigments is the installation and operation costs. Thus, basic and applied research is still needed to overcome such limitations and enable cyanobacteria to enter the global market. This review focuses on various cyanobacterial pigments, their applications, and current biotechnological approaches to increase the production of biopigments for their potential use in the pharmaceutical, food, and cosmetic industries. The current state of production technologies based on either open pond systems or closed photobioreactors was compared. The potential of scientific and technological advances to increase yield and reduce production costs of cyanobacteria biomass-based pigments was also discussed.