Biohydrogen production from engineered microalgae Chlamydomonas reinhardtii

Ayse Kose, Suphi S. Oncel
2014 Advances in Energy Research  
The green microalgae Chlamydomonas reinhardtti is well-known specie in the terms of H 2 production by photo fermentation and has been studying for a long time. Although the H 2 production yield is promising; there are some bottlenecks to enhance the yield and efficiency to focus on a well-designed, sustainable production and also scaling up for further studies. D1 protein of photosystem II (PSII) plays an important role in photosystem damage repair and related to H 2 production. Because
more » ... monas is the model algae and the genetic basis is well-studied; metabolic engineering tools are intended to use for enhanced production. Mutations are focused on D1 protein which aims long-lasting hydrogen production by blocking the PSII repair system thus O 2 sensitive hydrogenases catalysis hydrogen production for a longer period of time under anaerobic and sulfur deprived conditions. Chlamydomonas CC124 as control strain and D1 mutant strains (D240, D239-40 and D240-41) are cultured photomixotrophically at 80 μmol photons m -2 s -1 , by two sides. Cells are grown in TAP medium as aerobic stage for culture growth; in logarithmic phase cells are transferred from aerobic to an anaerobic and sulfur deprived TAP -S medium and 12 mg/L initial chlorophyll content for H 2 production which is monitored by the water columns and later detected by Gas Chromatography. Total produced hydrogen was 82 ± 10, 180 ± 20, 196 ± 20, 290 ± 30 mL for CC124, D240, D239-40, D240-41, respectively. H 2 production rates for mutant strains was 1.3 ± 0.5 mL/L.h meanwhile CC124 showed 2-3 fold lower rate as 0.57 ± 0.2 mL/L.h. Hydrogen production period was 5 ± 2 days for CC124 and mutants showed a longer production time for 9 ± 2 days. It is seen from the results that H 2 productions for mutant strains have a significant effect in terms of productivity, yield and production time.
doi:10.12989/eri.2014.2.1.001 fatcat:m3zh3dboy5e6le7pitaa4yr5uq