08.08.2015   Advanced Biofuels and Bioproducts

Chlorophyta (Green Algae)

Chlorophyll a and b are the dominant pigments in Chlorophyta and are the source of the second name of these organisms—Green algae. The secondary pigments are carotenoids (b-carotene, prasinoxanthin, siphonaxanthin, astaxanthin) which some­times give algae their yellowish-green and red-green colors [44]. The major habitat for green algae is freshwater although they are also found in sea or brackish water, and in soil [38, 39, 45, 46]. Chlorophyta species are unicellular or colonial motile and non-motile, filamentous, coccoid, parenchimatous, and siphonous [37, 47] .

Species

Reactor type

Ршы (g/m2-day)

P, Ota* (g/L-day)

References

Potphyridium cruentum

Airlift tubular (200 L)

—

1.5

[522]

Potphym

Natural population

3.6

—

[179]

Gracilaria chilensis

Outdoor tank

11.2

—

[523]

G. chilensis

Spray culture

0.5

—

[524]

G. tikvahiae (Florida)

Outdoor tank, aerated, nutrients (50 L)

12^46 (34.8™)

0.06-0.21 (0.16™)

[483. 525]

G. tikvahiae (Florida)

Same. AD effluent (2.4 m3)

25

—

[483]

G. tikvahiae

Tank, aerated, nutrients (2.4-24 m3)

22-25

—

[526]

Pond, non-aerated (9 m3)

5-8

—

G. tikvahiae (Florida)

Pond (non-aerated)

9.7

—

[527]

Pond (aerated)

11.5

—

Pond (large scale)

7.2

—

Cage culture

0^44 (13.9™)

—

G. tikvahiae (Taiwan)

Pond (<300 ha)

4.4-11.8

—

[528]

Palma via palmata

Natural population

0.65-2.3

—

[529]

Gracilaria sp. (Florida)

Tank, nutrients

7-16

—

[179]

P. palmata

Natural population

24

—

Hypnea muscifonnis

Tank, nutrients

12-17

—

Chondrus crispus

Tank

25-30

—

Rhodoglossum affine

Tank

12-30

—

Iridaea cordata

Natural population

4-14

—

I. cordata

Outdoor tank (1.4 m3)

1.95 (20.7““)

—

[530]

Table 6 Productivity of Rhodophyta species

36 Biogas Production from Algae and Cyanobacteria Through Anaerobic Digestion… 879

Component3

C. crispus

P. palmata

G. tikvahiae

Gracilaria verrucosa

Gracilaria cetvicornis

P. cmentum

Water

74.1-80.9

83-90

—

—

14.66± 1.78

—

Ash

27.3-35.7

20.2-28.8

29—42

25-29

10.5 ±1.6

20 ±2.4

Carbon

24.6-30.7

30-34.9

28.1-30.8

33.8-34.1

—

—

Hydrogen

3.6^4.5

4.5-5.6

4.5—4.6

4.3—4.7

—

—

Oxygen (calculated)

32.5-33.2

32.9-35.1

27.5-30.4

27.9-33.2

—

—

Nitrogen

3.1^4.7

3.8—4.1

3.7—4.8

3.4—4.7

3.2±0.4

—

Sulfur

3.8-5

0.5

—

—

—

1.41 ±0.16

Alginate

0.6-2

0.6-3.1

—

—

—

—

Fukoidan

0.4-0.7

0.1-9.7

—

—

—

—

Carrageenan + agar

11-22.6

15.6-30

44.6-53.7

39—45

—

—

Total carbohydrates

40.5-54.9

23.1-60.9

42.5-54.7

64-75.5

63.1 ±3.5

32.1 ±5.6

Protein

—

—

13.3-36.2

11.9-12.3

19.7±2.7

34.1 ±4.4

Lipids

—

—

—

—

0.43±0.06

6.53 ±0.46

Chlorophyll

—

—

—

—

—

0.25 ±0.15

Fiber

—

—

—

—

5.7±0.7

0.39±0.13

Cellulose

2—4.8

4—4.4

—

—

—

—

Sugars/alcohols

1-6

19.4-27.1

—

—

—

—

Polyphenols/lignin

2.2-3

2.1-2.8

—

—

—

—

C/N ratio References

5.9-7.9 [531]

7.9-8.5

5.32-7.72

[121]

[532]

‘All data are given as a % from dry weight, water as a % from fresh weight and C/N ratio unit less

880 P. Bohutskyi and E. Bouwer

Table 8 Chlorophyta species major organic matter characteristics

Characteristic Description References

Nutrient reserves Chlorophycean: mix of amylose [511,533-540]

(a-1,4-linkage) and amylopectine (a-1,4 and a-1,6 linkage) inside of chloroplast Lipids

Polyphosphate granules

Cell wall organization Mostly two layered [161,162,170,541-549]

Outer mucilage or capsule Structural component—crystalline

cellulose (Cladophorales), amorphous cellulose (Ulvales, Oedogoniales, coccoid algae), xylose or mannose (Caulerpales, Codiaceae,

Polyphysaceae) in hemicellulose, glycoproteins (Volvocales)

Several microalgae (e. g., Chlorellaceae,

Scenedesmaceae, Hydrodictyaceae families) have resistant trilaminar structure containing nonhydrolysable biopolymer—algaenan Some marine siphonous species are

______________________ calcified with CaCO3___________________________________

Halophilic microalga Dunaliella is widely cultivated for the production of b-carotene and other human nutritional products [48]. Species from Ulvophyceae group are mostly marine macroscopic algae that are used as food in coastal regions and can be used for nitrogen removal during wastewater treatment [49] (Tables 8-10).