Biohydrogen production by a novel integration of dark fermentation and mixotrophic microalgae cultivation

Abstract Biohydrogen is usually produced via dark fermentation, which generates CO2 emissions and produces soluble metabolites (e.g., volatile fatty acids) with high chemical oxygen demand (COD) as the by-products, which require further treatments. In this study, mixotrophic culture of an isolated microalga (Chlorella vulgaris ESP6) was utilized to simultaneously consume CO2 and COD by-products from dark fermentation, converting them to valuable microalgae biomass. Light intensity and food to microorganism (F/M) ratio were adjusted to 150 μmol m−2 s−1 and F/M ratio, 4.5, respectively, to improve the efficiency of assimilating the soluble metabolites. The mixotrophic microalgae culture could reduce the CO2 content of dark fermentation effluent from 34% to 5% with nearly 100% consumption of soluble metabolites (mainly butyrate and acetate) in 9 days. The obtained microalgal biomass was hydrolyzed with 1.5% HCl and subsequently used as the substrate for bioH2 production with Clostridium butyricum CGS5, giving a cumulative H2 production of 1276 ml/L, a H2 production rate of 240 ml/L/h, and a H2 yield of 0.94 mol/mol sugar.

[1]  Debabrata Das,et al.  Hydrogen production by biological processes: a survey of literature , 2001 .

[2]  F. Kargı,et al.  Bio-hydrogen production from waste materials , 2006 .

[3]  Jo-Shu Chang,et al.  Microalgal biomass production and on-site bioremediation of carbon dioxide, nitrogen oxide and sulfur dioxide from flue gas using Chlorella sp. cultures. , 2011, Bioresource technology.

[4]  Jo‐Shu Chang,et al.  Combining enzymatic hydrolysis and dark–photo fermentation processes for hydrogen production from starch feedstock: A feasibility study , 2008 .

[5]  L. Brown,et al.  Growth inhibition by high light intensities in algae from lakes undergoing acidification , 1989, Hydrobiologia.

[6]  Jo‐Shu Chang,et al.  Photoheterotrophic growth of Chlorella vulgaris ESP6 on organic acids from dark hydrogen fermentation effluents. , 2013, Bioresource technology.

[7]  Jo‐Shu Chang,et al.  Photo fermentative hydrogen production using dominant components (acetate, lactate, and butyrate) in , 2011 .

[8]  D. L. Hawkes,et al.  Sustainable fermentative hydrogen production: challenges for process optimisation , 2002 .

[9]  Teresa M. Mata,et al.  Microalgae for biodiesel production and other applications: A review , 2010 .

[10]  Y. Wong,et al.  Wastewater Nutrients (N and P) Removal by Carrageenan and Alginate Immobilized Chlorella Vulgaris , 1997 .

[11]  Yanna Liang,et al.  Biomass and lipid productivities of Chlorella vulgaris under autotrophic, heterotrophic and mixotrophic growth conditions , 2009, Biotechnology Letters.

[12]  Jo‐Shu Chang,et al.  Fermentative hydrogen production with Clostridium butyricum CGS5 isolated from anaerobic sewage sludge , 2005 .

[13]  Harold C. Bold,et al.  The Morphology of Chlamydomonas chlamydogama, Sp. Nov. , 1949 .

[14]  Jo-Shu Chang,et al.  Dark fermentative hydrogen production from enzymatic hydrolysate of xylan and pretreated rice straw by Clostridium butyricum CGS5. , 2010, Bioresource technology.

[15]  Jo‐Shu Chang,et al.  Cultivation, photobioreactor design and harvesting of microalgae for biodiesel production: a critical review. , 2011, Bioresource technology.

[16]  Ana Cristina Oliveira,et al.  Microalgae as a raw material for biofuels production , 2009, Journal of Industrial Microbiology & Biotechnology.

[17]  Y. Bashan,et al.  Increased Growth of the Microalga Chlorella vulgariswhen Coimmobilized and Cocultured in Alginate Beads with the Plant-Growth-Promoting Bacterium Azospirillum brasilense , 2000, Applied and Environmental Microbiology.

[18]  Jo‐Shu Chang,et al.  Biosorption of cadmium by CO(2)-fixing microalga Scenedesmus obliquus CNW-N. , 2012, Bioresource technology.

[19]  Duu-Jong Lee,et al.  Bioreactor and process design for biohydrogen production. , 2011, Bioresource technology.

[20]  Lawrence Pitt,et al.  Biohydrogen production: prospects and limitations to practical application , 2004 .

[21]  Heguang Zhu,et al.  Phototrophic hydrogen production from glucose by pure and co-cultures of Clostridium butyricum and Rhodobacter sphaeroides , 2006 .

[22]  Jo‐Shu Chang,et al.  Biohydrogen production from lignocellulosic feedstock. , 2011, Bioresource technology.

[23]  L. Xia,et al.  Enzymatic hydrolysis of maize straw polysaccharides for the production of reducing sugars , 2008 .

[24]  Shu-wen Huang,et al.  Characterization and optimization of carbohydrate production from an indigenous microalga Chlorella vulgaris FSP-E. , 2013, Bioresource technology.

[25]  Duu-Jong Lee,et al.  Fermentative hydrogen production by Clostridium butyricum CGS5 using carbohydrate-rich microalgal biomass as feedstock , 2012 .

[26]  Debabrata Das,et al.  Continuous hydrogen production by immobilized Enterobacter cloacae IIT-BT 08 using lignocellulosic materials as solid matrices. , 2001 .

[27]  António A. Vicente,et al.  Nutrient limitation as a strategy for increasing starch accumulation in microalgae , 2011 .

[28]  Jo‐Shu Chang,et al.  Perspectives on microalgal CO₂-emission mitigation systems--a review. , 2011, Biotechnology advances.

[29]  Jo-Shu Chang,et al.  Sequential dark–photo fermentation and autotrophic microalgal growth for high-yield and CO2-free biohydrogen production , 2010 .

[30]  M. Frąc,et al.  Methane fermentation process as anaerobic digestion of biomass: Transformations, stages and microorganisms , 2012 .

[31]  Jo‐Shu Chang,et al.  Dark H2 fermentation from sucrose and xylose using H2-producing indigenous bacteria: feasibility and kinetic studies. , 2008, Water research.

[32]  G. L. Miller.  Use of Dinitrosalicylic Acid Reagent for Determination of Reducing Sugar , 1959 .

[33]  K. Mosbach,et al.  Formation of α-keto acids from amino acids using immobilized bacteria and algae , 1982, Biotechnology Letters.