Chlorellais single-cell algae of Chlorophyceae, falling into the Generally Regarded as Safe (GRAS) category.Chlorellais rich in proteins, essential amino acids (EAAs), vitamins, minerals (potassium, sodium, magnesium, iron, and calcium), β-carotene, chlorophylls, as well as other health-promoting substances. Because of its high protein content, they are treated as ideal sources of proteins and applied as raw materials in functional food, food additives, and pharmaceutical products.

Chlorellais generally thought of as photosynthetic microorganisms, gaining energy through light by fixing atmospheric CO2. However, low biomass yields, the requirement of cultivation systems with the large surface area are some of the inherent disadvantages. When compared to autotrophic cultivation, heterotrophic systems are more suitable for producing high cell densities to accumulate large quantities of commodities for food products.

In this study, a high-protein mutant K05 ofChlorellawas generated by heavy-ion irradiation mutagenesis followed by targeted screening. Assessment of different production scenarios of the K05 mutant revealed the stability, scalability, and sustainability for production of nutrition-added chemicals by the strain using fermentation with low-cost sweet sorghum juice. These results have important implications for the viable development of functional food usingChlorella/microalgae via optimized cultivation techniques integrated with artificial trait-improvement of industrial strains.

This work is supported by the National Natural Science Foundation of China, and Project of Innovation & Development of Marine Economy.

Publication:

Song, Xiaojin, Wang, J., Wang, Y., Feng, Y., Cui, Q., Lu, Y., 2018. Artificial creation ofChlorella pyrenoidosamutants for economic sustainable food production.Bioresource Technology268, 340-345.