Photo-fermentational hydrogen production of Rhodobacter sp. KKU-PS1 isolated from an UASB reactor
| Autor: | Alissara Reungsang, Thitirut Assawamongkholsiri |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
nifH
Central composite design Hydrogen lcsh:Biotechnology nifD chemistry.chemical_element Dark fermentation Biology Applied Microbiology and Biotechnology chemistry.chemical_compound Light intensity lcsh:Biology (General) chemistry lcsh:TP248.13-248.65 Botany Malic acid Anaerobic bacteria Photosynthetic bacteria Photo fermentation lcsh:QH301-705.5 Purple-non-sulfur bacteria Biotechnology Nuclear chemistry Hydrogen production |
| Zdroj: | Electronic Journal of Biotechnology, Volume: 18, Issue: 3, Pages: 221-230, Published: MAY 2015 Electronic Journal of Biotechnology v.18 n.3 2015 SciELO Chile CONICYT Chile instacron:CONICYT Electronic Journal of Biotechnology, Vol 18, Iss 3, Pp 221-230 (2015) |
| ISSN: | 0717-3458 |
| DOI: | 10.1016/j.ejbt.2015.03.011 |
| Popis: | Normal 0 21 false false false EN-US X-NONE TH Background : Purple non‑sulfur photosynthetic bacteria (PNSB) are among the potential bio‑hydrogen producers. PNSB can produce a higher hydrogen yield in comparison to dark fermentation by anaerobic bacteria. In this study, the detection of nifH and nifD by a polymerase chain reaction (PCR) assay was used to screen the potential photosynthetic bacteria capable of producing hydrogen from five different environmental sources. Since the efficiency of photo-hydrogen production is highly dependent on the culture conditions, initial pH, temperature and illumination intensity were optimized for maximal hydrogen production. The experiments were designed using response surface methodology (RSM) with central composite design (CCD). Results : Rhodobacter sp. KKU-PS1 (GenBank accession no. KC478552) was isolated from the methane fermentation broth of an UASB reactor. Malic acid was the favored carbon source while Na-glutamate was the best nitrogen source. The optimum conditions for simultaneously maximizing the cumulative hydrogen production (H max ) and hydrogen production rate (R m ) from malic acid were an initial pH of 7.0, a temperature of 25.6oC, and an illumination intensity of 2500 lux. H max and R m levels of 1264 mL H 2 /l and 6.8 mL H 2 /l‑h were obtained, respectively. The optimum initial pH and temperature were further used to optimize the illumination intensity for hydrogen production. An illumination intensity of 7500 lux gave the highest values of H max (1339 mL H 2 /l) and R m (12.0 mL H 2 /l‑h) with a hydrogen yield and substrate conversion efficiency of 3.88 moL H 2 /moL malate and 64.7%, respectively. Conclusions: Rhodobacter sp. KKU-PS1 is an efficient bio-hydrogen producer capable of producing hydrogen from at least eight types of organic acids. A maximal hydrogen production by this strain was obtained by optimizing pH and temperature. Additionally, by optimizing the light intensity, R m was increased by approximately two fold and the lag phase of hydrogen production was shortened. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; mso-bidi-font-size:14.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-ansi-language:EN-US; mso-fareast-language:EN-US; mso-bidi-language:TH;} |
| Databáze: | OpenAIRE |
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