title: Microbial cell immobilization in biohydrogen production: a short overview.
abstract: The high dependence on fossil fuels has escalated the challenges of greenhouse gas emissions and energy security. Biohydrogen is projected as a future alternative energy as a result of its non-polluting characteristics, high energy content (122 kJ/g), and economic feasibility. However, its industrial production has been hampered by several constraints such as low process yields and the formation of biohydrogen-competing reactions. This necessitates the search for other novel strategies to overcome this problem. Cell immobilization technology has been in existence for many decades and is widely used in various processes such as wastewater treatment, food technology, and pharmaceutical industry. In recent years, this technology has caught the attention of many researchers within the biohydrogen production field owing to its merits such as enhanced process yields, reduced microbial contamination, and improved homogeneity. In addition, the use of immobilization in biohydrogen production prevents washout of microbes, stabilizes the pH of the medium, and extends microbial activity during continuous processes. In this short review, an insight into the potential of cell immobilization is presented. A few immobilization techniques such as entrapment, adsorption, encapsulation, and synthetic polymers are discussed. In addition, the effects of process conditions on the performance of immobilized microbial cells during biohydrogen production are discussed. Finally, the review concludes with suggestions on improvement of cell immobilization technologies in biohydrogen production.
authors.affiliation: a School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment , University of the Witwatersrand , Johannesburg , South Africa.
authors.forename: Patrick Thabang
authors.initials: PT
authors.lastname: Sekoai
authors.affiliation: a School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment , University of the Witwatersrand , Johannesburg , South Africa.
authors.forename: Ayotunde A
authors.initials: AA
authors.lastname: Awosusi
authors.affiliation: a School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment , University of the Witwatersrand , Johannesburg , South Africa.
authors.forename: Kelvin Odafe
authors.initials: KO
authors.lastname: Yoro
authors.affiliation: a School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment , University of the Witwatersrand , Johannesburg , South Africa.
authors.forename: Muofhe
authors.initials: M
authors.lastname: Singo
authors.affiliation: a School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment , University of the Witwatersrand , Johannesburg , South Africa.
authors.forename: Olawale
authors.initials: O
authors.lastname: Oloye
authors.affiliation: a School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment , University of the Witwatersrand , Johannesburg , South Africa.|b Department of Chemical Engineering, College of Engineering , Covenant University , Ota , Ogun State , Nigeria.
authors.forename: Augustine Omoniyi
authors.initials: AO
authors.lastname: Ayeni
authors.affiliation: a School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment , University of the Witwatersrand , Johannesburg , South Africa.|c Department of Metallurgical and Materials Engineering , Federal university of Technology , Akure , Ondo State , Nigeria.
authors.forename: Michael
authors.initials: M
authors.lastname: Bodunrin
authors.affiliation: a School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment , University of the Witwatersrand , Johannesburg , South Africa.
authors.forename: Michael Olawale
authors.initials: MO
authors.lastname: Daramola
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D018914:Cells, Immobilized / Q000378:metabolism*; D006859:Hydrogen / Q000378:metabolism*
chemical_list: D006859:Hydrogen
keywords: Biohydrogen; cell immobilization; microorganisms; process parameters