Table 5 Gifts, bottlenecks, and key technologies in biomass production of some important commercial microalgae

Arthrospira sp.

• High growth rate

• Grown in alkaline conditions

• High NaHCO₃ consumption

• High growth temperature requirements

• Autotrophic

• CO₂ replenishment technology in raceway ponds

• Breeding techniques for low temperature tolerant strains

12,000

[25]

Chlorella sp.

• High growth rate

• Multitrophic mode

• Low level of photosynthetically derived compounds in heterotrophic mode

• Autotrophic

• Heterotrophic

• High cell-density heterotrophic cultivation process

• SHDP process

5000

[26]

D. salina

• High β-carotene content under stress conditions

• Grown in high salinity conditions

• High medium costs

• D. salina cells are fragile and difficult in harvesting

• Autotrophic

• Salt-making mother liquor or natural seawater used as medium for D. salina culture

• Flotation process used for D. salina harvesting

• Two-step cultivation process

1200

[27]

H. pluvialis

• High astaxanthin content under stress conditions

• Sensitive to biological contaminants

• Astaxanthin is easy to be oxidized

• Autotrophic

• Two-step cultivation process

• Microencapsulation process for H. pluvialis powder and astaxanthin

800

[28]

E. gracilis

• High growth rate

• Multitrophic mode

• Low pH tolerance

• Low level of photosynthetically derived compounds in heterotrophic mode

• Autotrophic

• Heterotrophic

• SHDP process

70

[29, 30]

N. sphaeroides

• Cell population growth

• Sensitive to biological contaminants

• High requirements for aquaculture water quality

• Autotrophic

• Breeding techniques for high quality strains

• Water treatment technology for water hardness reduction

200 (fresh weight)

[6]