Microalgae, their extensive application potential in the renewable energy, biopharmaceutical, and nutraceutical industries have recently attracted considerable interest worldwide. Microalgae are renewable, sustainable, and economical sources that’s leads to a resurgence of interest in micro algal research. In the near past several microalgae species have been investigated for their potential as value-added products with remarkable pharmacological and biological qualities.

As biofuels, microalgae are a perfect substitute to liquid fossil fuels with respect to cost, renewability, and environmental concerns. Microalgae have a significant ability to utilize atmospheric CO₂ to useful products such as carbohydrates, lipids, and other bioactive metabolites. Even though microalgae are feasible sources for bioenergy and biopharmaceuticals in general, some limitations and challenges remain, which must be overcome to upgrade the technology from pilot-phase to industrial level. 

In nature microalgae are a diverse group of unicellular organismsthat includes prokaryotic cyanobacteria and eukaryotic photosynthetic microorganisms that inhabit freshwater and marine habitats. Microalgae can be utilized in various industries, including as food for human consumption, as animal feed, in aquaculture, in cosmetics and as biofuels. Due to their photoautotrophic nature, with minimal nutritional requirements, microalgae have advantages compared to other microbial cells. Furthermore, recent research on microalgae genomics are revealing a variety of novel genes that need to be investigated for biotechnological applications. Genetic diversity exploration of these photosynthetic microorganismswill also enable the efficientuse of algae as recombinant enzyme biofactories that will be useful to industry.

Algae genetic diversity and potential for enzyme production

 Plastids or Chloroplasts were primarily derived from the endosymbiotic uptake of a cyanobacterium. Subsequently,through subsequent rounds ofsecondary and even tertiary endosymbiosisof these primary plastids (such as those found in chlorophytes and rodophytes) were leads to spread to other eukaryotic clades.12 of the 45 major eukaryotic clades and, in the prokaryotic cyanobacteria cladethrough evolutionary events led to the presence of the “algal phenotype” characterized as photosynthetic unicellular or pluricellular (without tissue organization) organisms found in humid environments. The number of eukaryotic algal species was estimated to be72,500 and the number of cyanobacteria species was estimated at approximately 6,000 using conservative approaches. Therefore, a huge polyphyletic genetic reservoir lies inside these simple algal morphologic features orders of magnitude larger than that found within animals or plant taxa.

Microalgal enzymes

Enzymes from microorganisms could be used as catalysts in diverse industrial processes. The search for new sources of microbial enzymes is ongoing and requires sustainable solutions. In 2014, the global market for industrial enzymes was estimated at USD 4.2 billion and is expected to reach nearly USD 7.1 billion by 2018. The industrialmarket for  these microbial enzymes is expected to grow at a CAGR of 6.83% during the forecast period of 2019-2024. Major factors driving the market are the growing diversity in enzyme applications and niche products and stringent environmental norms curbing the use of chemicals.Although there is no industrial production of enzymes from microalgae, several reports show the great capacity of microalgae cells to synthesize enzymes. Different classes of enzymes were reported, including hydrolases, oxidoreductases and lyases. Anabaena and Porphyridium produce the enzyme SOD (superoxide dismutase), which protects against oxidative damages, while Isochrysisgalbana produces the vital enzyme carbonic anhydrase, which plays a crucial role in converting CO₂ into carbonic acid and bicarbonate.

Different groups of enzymes from microalgae

Conclusion

Cyanobacterial and microalgal systems have many advantages over traditional energy crops however, its production could become economically feasible in the future when biotechnical, environmental and economic hurdles will be surmounted. Ultimately, cyanobacteria offer the potential to have a profound impact on the future welfare of the planet by addressing the pressing issues of alternative energy resources, global warming, human health and food security. Nonetheless, we believe the time is now to implement the advanced technologies, which are based on sustainable and renewable systems, to address current international issues.

Reference

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