Algae-Mediated Carbon Dioxide Sequestration for Climate Change Mitigation and Conversion to Value-Added Products - Biotechnological Applications of Microalgae - page 167

TABLE 11.3
Oil Content of Some Selected Microalgae

Oil Content
(% Dry Wt)

Volumetric Productivity
of Biomass (g L −1 d −1 ) Sr. No. Microalgae

1 Botryococcus braunii 25-75 0.02

2 Chlorella emersonii 29 0.036−0.041

3 Chlamydomonas reinhardtii 21 -

4 Chlorella minutissima 31 -

5 Chlorella protothecoides 13 2-7.70

6 Chlorella pyrenoidosa 18 2.90-3.64

7 Chlorella sorokiniana 16 0.23-1.47

8 Chlorella vulgaris 25 0.02-2.5

9 Crypthecodinium cohnii 20 10

10 Cylindrotheca sp. 16-37 -

11 Dunaliella primolecta 23 0.09

12 Dunaliella salina 19 0.22-0.34

13 Dunaliella tertiolecta 15 0.12

14 Euglena gracilis 20 7.70

15 Isochrysis sp. 25-33 0.08-0.17

16 Monallanthus salina N 20 0.08

17 Nannochloris sp. 20-35 0.17-0.51

18 Nannochloropsis sp. 31-68 0.17-1.43

19 Neochloris oleoabundans 35-54 -

20 Nitzschia sp. 45-47 -

21 Phaeodactylum tricornutum 20-30 0.003-1.9

22 Schizochytrium sp. 50-77 -

23 Tetraselmis sueica 15-23 0.12-0.32

Source: Adapted from Griffiths and Harrison (2009); Mata, et al. (2010); and Chisti (2007).

Enhancement of CO 2 sequestration and lipid accumulation is one of the major
challenges that can be duly addressed by an extensive search for the new genes
involved in the process (bio-prospecting) or targeted genetic engineering, both of
which are promising approaches (Kumar et al., 2010).
Genetic and metabolic engineering transformations in microalgae are lim-
ited to very few microalgal species. The use of molecular biology techniques as
a toolkit to engineer microalgae for biodiesel production is a demanding strategy.
Understanding, incorporation, and expression of the gene encoding rate-limiting
enzyme of inorganic carbon uptake and lipid biosynthetic pathways are of more
importance (Badger and Price, 2003; Verma et al., 2010). With the advancements
in genome sequencing with sequence availability of Anabaena, Ostreococcus tauri,
Thalassiosira pseudonana, and other algal species (Beer et al., 2009; Verma et al.,
2010), the genetic transformation of microalgal species for various purposes is now
promising. Cyclotella cryptica and Navicula saprophila were genetically trans-
formed with the acetyl-CoA carboxylase (acc) gene isolated from Cyclotella cryptica