Table 2.
Maximum H2 productivity achieved by Chlamydomonas using different approaches. Data are ranked according to the total H2 production yield. For each study, only the maximum reported values are considered.
| Strategy | Parental Alga Strain | Mutant Strain | Conditions | Reported H2 Production | Estimated H2 Production (mL/L)1,2 | Estimated Average H2 Production rate (mL/L∙d) | Reference |
|---|---|---|---|---|---|---|---|
| Monoculture/Genetic modification/S deprivation | cc124 | pgrl5 | TAP-S, 60 PPFD | 850 mL/L (9 days) | 850 | ≈94.4 | [69] |
| Monoculture/Genetic modification/S deprivation | cc1618 | stm6 | TAP-S, 100 PPFD | 540 mL/L (14 days) | 540 | ≈38.6 | [70] |
| Monoculture/Genetic modification/S deprivation | 11/32b | L159I-N230Y | TAP-S, 70 PPFD | 504 mL/L (12 days) | 504 | ≈42 | [71] |
| Monoculture/Genetic modification/S deprivation | 137c(cc124) | pgrl1 | TAP-S, 200 PPFD | ≈1.5 mmol/mg chl (≈5 days) |
≈437 | ≈87.4 | [34] |
| Monoculture/Genetic modification/S deprivation | cc1618 | Stm6Glc401 | TAP-S + 1 mM glucose, 450 PPDF | 361 mL/L (≈8 days) | 361 | ≈46 | [72] |
| Consortia/Pseudomonas sp. /S deprivation |
FACHB-265 | -- | TAP-S, 200 PPFD | 170.8 mL/L (13 days) | 170.8 | 13.1 | [59] |
| Consortia/Bradirizhobium japonicum/S deprivation | cc849 | Transgenic lba strain | TAP-S, 60 PPFD | 298.54 µmol/40 mL (14 days) | ≈170.5 | ≈11.95 | [57] |
| Consortia/Bradirizhobium japonicum/S deprivation | cc503 | -- | TAP-S, 200 PPFD | 310 µmol/mg chl (16 days) |
≈164.9 | ≈10.3 | [58] |
| Monoculture/S deprivation | 137c (cc125) | -- | TAP-S | ≈155 mL/L (≈4 days) | ≈155 | ≈38.75 | [36] |
| Monoculture/Mg deprivation | 137c (cc125) | -- | TAP-Mg, 80 PPFD | 6.3 mmol/L (≈8 days) | ≈141.1 | ≈16.9 | [73] |
| Monoculture/S deprivation/acetate free | UTEX 90 (cc1010) | -- | T(A)P-S3, 50 PPFD, N2 purging | 118 mL/L (4.5 days) | 118 | 26.2 | [74] |
| Monoculture/O2 scavenging | cc503 | -- | TAP + NaHSO3, 200 PPFD | ≈150 µmol/30mL (3 days) | ≈112.05 | ≈37.3 | [75] |
| Monoculture/Genetic modification | cc849 | hemHc-lbac | TAP-S, N2 purging, dark incubation, 50 PPFD | 3.3 mL/40 mL (≈5 days) |
82.5 | ≈16.5 | [76] |
| Monoculture/Light modulation | cc124/cc4533 | -- | TAP, 1 s light pulses (180 PPFD) + 9 s dark periods under Argon atmosphere | 3.26 mmol/L (2.25 days) | ≈73.06 | ≈32.5 | [29] |
| Monoculture/acetic acid supplementation/Light modulation | 704 | -- | TAP + acetic acid supplementation, daily aeration, 12 PPFD | 65 mL/L (9 days) | 65 | ≈10 | [14] |
| Consortia/E. coli (hypF)/S deprivation | cc124 | -- | TAP-S, 50 PPFD | 47.2 mL/L (7 days) |
47.2 | 6.75 | [60] |
1 Avogadro’s law for ideal gas is considered to estimate H2 productivity in the unit of (mL/L culture): 1 mole H2 gas (at pressure= 101.325 kPa and temperature=273.15 K) is equal to 22.41 liters of H2; 2 the average of the lowest and the highest chlorophyll concentration was considered to estimate the H2 productivity from “per mg chlorophyll” to “per liter culture”; 3 Tris–Acetate–Phosphate (TAP) without acetate and sulfur (T(A)P-S); “≈”: Data estimated from the original study (rounded values); photosynthetic photon flux density (PPFD) (µmol photons · m2−1 · s−1).