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An Overview of Fermentative Hydrogen Production Technologies
Published in Sonil Nanda, Prakash K. Sarangi, Biohydrogen, 2022
Prakash K. Sarangi, Sonil Nanda, Ajay K. Dalai, Janusz A. Kozinski
Biophotolysis of water is one of the alternatives for the production of biohydrogen by green algae and blue-green algae (cyanobacteria) directly or indirectly. In these processes, microorganism splits the water molecule into hydrogen ions and oxygen (Caudillo-Flores et al., 2017). The produced hydrogen ions are converted to hydrogen gas by the help of electrons contributed by reduced ferredoxin, which is supported by hydrogenase enzymes found in the microbial cells (Winkler et al., 2002). Cyanobacteria are photoautotrophic microorganisms that perform photosynthesis producing hydrogen in two stages (Levin et al., 2004). Various photosynthetic pigments such as chlorophyll, carotenoids, and phycobiliproteins are possessed by these cyanobacteria that support hydrogen production through the enzymes like hydrogenase and nitrogenase (Pinto et al., 2002). Anabaena cylindrica is a hydrogen-producing cyanobacterium, whereas Anabaena variabilis is hydrogen at high yields (Rupprecht et al., 2006). As the production of hydrogen from water takes place by two stages, it is regarded as the indirect bio-photolysis. Some nitrogen-fixing and non-nitrogen fixing hydrogen-producing cyanobacteria are employed in this process (Liu et al., 2006).
Algal photobiohydrogen production
Published in Ozcan Konur, Bioenergy and Biofuels, 2017
Archana Tiwari, Thomas Kiran, Anjana Pandey
There is variation in light requirement by algal species for optimum hydrogen production. Some algae produce hydrogen in the presence of light, while some produce in both light and dark conditions. Nitrogen-fixing cells of Anabaena variabilis SPU 003 have the capacity to produce hydrogen mainly in darkness. Spirulina platensis is reported to produce hydrogen under anaerobic conditions, both in the dark and in the light, but several other species produce hydrogen only in the presence of light. In Synechococcus elongatus PCC 7942, hydrogen production mediated by native hydrogenases occurs under in the dark under anaerobic conditions. S. platensis can produce hydrogen optimally at 32°C in complete anaerobic and dark conditions. In A. variabilis PK 84, hydrogen production was stimulated by light (Tsygankov et al., 1999). Hydrogen production in Nostoc muscorum is catalyzed by nitrogenase; more hydrogen is produced in this strain in the light than in the dark. A. cylindrica produces hydrogen under an argon atmosphere for 30 days in limited light (luminous intensity 6.0 W/m−2) and 18 days under elevated light (luminous intensity 32 W/m−2). Continuous hydrogen production by A. cylindrica for a prolonged period under light-limited conditions occurs in the absence of exogenous nitrogen. The effect of light on nitrogenase-mediated hydrogen production by most cyanobacteria is well studied. Nitrogenase function is saturated only at much higher light intensities than required for optimal growth. The rate of hydrogen production rates can be doubled if the luminous intensity exposure to cultures is changed from 20 to 60 W/m2 (Hallenbeck et al., 1978).
Production of Biofuels
Published in K.A. Subramanian, Biofueled Reciprocating Internal Combustion Engines, 2017
Cyanobacteria require air, water, minerals, and light. In this process, hydrogen is produced by both hydrogenase and nitrogenase. Cyanobacteria like Anabaena cylindrica, and Anabaena variabilis are involved in the process of hydrogen production.
The role of silver nanoparticles biosynthesized by Anabaena variabilis and Spirulina platensis cyanobacteria for malachite green removal from wastewater
Published in Environmental Technology, 2021
Gehan A. Ismail, Nanis G. Allam, Walaa M. El-Gemizy, Mohamed A. Salem
Silver nanoparticles (AgNPs) were biosynthesized by Anabaena variabilis and Spirulina platensis cyanobacteria species.AgNPs were applied as biosorbent for the removal of malachite green (MG) dye from wastewater solution.The removal efficiency reached 88% by S. platensis AgNPs and 81% by A. variabilis AgNPs.The removal process followed first-order kinetics.The resulted water effluents, after AgNPs treatment, proved non-toxic to Triticum aestivum L seedlings, implying a safe use for cultivation practices.
Waste into energy conversion technologies and conversion of food wastes into the potential products: a review
Published in International Journal of Ambient Energy, 2021
Jeya Jeevahan, A. Anderson, V. Sriram, R. B. Durairaj, G. Britto Joseph, G. Mageshwaran
Direct photolysis is used for biohydrogen production from water by algae/ cyanobacteria. When algae/ cyanobacteriaare used in the presence of solar energy, they split water molecules into hydrogen ion and oxygen through photosynthesis. The hydrogen ions are then converted into hydrogen gas with the help of hydrogenase enzymes, though some cyanobacteria might also use nitrogenase. Chlamydomonasreinhardtii, Scenedesmusobliquus, Playtmonassubcordiformis, Chlorella fusca are well-known algae used for the production of biohydrogen. Anabaena sp., Calothrix sp., Oscillatoria sp., Synechococcus sp., Gloebacter sp., Anabaena cylindrical and Anabaena variabilis are some of the cyanobacteria used in the biohydrogen production. The conversion of water molecules into hydrogen gas by algae may be represented by the following reaction. The conversion of water molecules into hydrogen gas by cyanobacteria may be represented by the following reactions.
Review of catalytic activities of biosynthesized metallic nanoparticles in wastewater treatment
Published in Environmental Technology Reviews, 2021
Alex Kwasi Saim, Philip Clinton Offei Adu, Richard Kwasi Amankwah, Millicent Nkrumah Oppong, Francis Kwaku Darteh, Abdul Wasiu Mamudu
Moreover, biosynthesis of spherical to oval-shaped AgNPs using two species of cyanobacteria, Anabaena variabilis and Spirulina platensis were investigated and evaluated for MG dye removal. Average particle sizes were 17.9 and 26.4 nm for S. platensis and A. variabilis, respectively. The percentage removal was 93% for S. platensis and 82% for A. variabilis AgNPs as the dye concentration decreased. The findings also showed that higher concentration of the AgNPs improved the performance of MG removal up to 88% and 81% for S. platensis and A. variabilis AgNPs. Due to the smaller sized S. platensis AgNPs, its catalytic activity for dye removal was better than A. variabilis [106]. Biosynthesized AgNPs using extracts of Bacillus pumilus, Bacillus paralicheniformis and Sphingomonas paucimobilis showed outstanding catalytic performance for the removal of MG dye from aqueous solution within 160 min. The AgNPs obtained were spherical to oval in shape, ranged from 4 to 20 nm in size, and 118 m2/g surface area [107]. Additionally, AgNPs of size range from 24 to 58 nm biosynthesized by Pseudomonas aeruginosa were excellent catalysts for the degradation of Bromothymol blue (87%) and Fantacell dye (87%) for 150 and 45 min, respectively [108].