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Tatyana Laurinavichene, Darya Tekucheva, Kestutis Laurinavichius, Anatoly Tsygankov
In this study, distillery wastewater was treated by dark fermentation or photofermentation alone, and by sequential dark and photofermentation processes using anaerobic saccharolytic consortium and purple nonsulfur bacteria. Combination of dark and photofermentation resulted in the maximal H2 yield of 17.6L/L of distillery waste with chemical oxygen demand 40g/L. It is equivalent to 205kJ/L distillery wastewater and corresponds to recovery of approximately 4-8% of energy consumed during ethanol production. Optimal performance of photofermentation was observed at 20% concentration of pre-fermented distillery waste...
March 2018: Enzyme and Microbial Technology
Tatyana Laurinavichene, Kestutis Laurinavichius, Evgeny Shastik, Anatoly Tsygankov
OBJECTIVES: To prove the possibility of efficient starch photofermentation in co-culture of heterotrophic and phototrophic bacteria over prolonged period. RESULTS: Repeated batch photofermentation of starch was demonstrated in co-culture Clostridium butyricum and Rhodobacter sphaeroides under microaerobic conditions. It continued 15 months without addition of new inoculum or pH regulation when using 4-5 g starch l-1 and 0.04 g yeast extract l-1 . The complete degradation of starch without volatile fatty acids accumulation was shown in this co-culture...
February 2018: Biotechnology Letters
E Corneli, A Adessi, E J Olguín, G Ragaglini, D A García-López, R De Philippis
AIMS: Aim of the paper was to assess the feasibility of producing hydrogen as a biofuel by photofermentation of fermented water lettuce (Pistia stratiotes L.) waste biomass, after a nitrogen-stripping treatment. METHODS AND RESULTS: A natural (42OL) and an engineered strain (CGA676, with low-ammonium sensitivity) of Rhodopseudomonas palustris were used for producing hydrogen. The stripping procedure was highly effective for ammonium removal, with an acceptable selectivity (91% of ammonium was removed; only 14% of total organic acids were lost)...
October 3, 2017: Journal of Applied Microbiology
Jian Zhang, Jie Yuan, Wen-Xue Zhang, Wen-You Zhu, Fang Tu, Ya Jiang, Chuan-Ze Sun
This paper reports an effective process for converting soy sauce residue into feeds by combining moderate acid hydrolysis and ammonization with Rhodospirillum rubrum fermentation. After pretreatment with dilute sulfuric or phosphoric acid (1%, w/w) at 100 °C, materials were subjected to fermentation under several gases (N2 , CO2 , and air) and different light intensities in a 2-L fermentor. Following sulfuric acid treatment, the true protein increased from 188 to 362 g kg-1 and the crude fiber decreased from 226 to 66 g kg-1 after fermentation at 0...
September 25, 2017: World Journal of Microbiology & Biotechnology
Carolina Zampol Lazaro, Zeynep Yilmazer Hitit, Patrick C Hallenbeck
Hydrogen yields of dark fermentation are limited due to the need to also produce reduced side products, and photofermentation, an alternative, is limited by the need for light. A relatively new strategy, dark microaerobic fermentation, could potentially overcome both these constraints. Here, application of this strategy demonstrated for the first time significant hydrogen production from lactate by a single organism in the dark. Response surface methodology (RSM) was used to optimize substrate and oxygen concentration as well as inoculum using both (1) regular batch and (2) O2 fed batch cultures...
December 2017: Bioresource Technology
Emrah Sagir, Ebru Ozgur, Ufuk Gunduz, Inci Eroglu, Meral Yucel
Biohydrogen production via fermentative routes offers considerable advantages in waste recycling and sustainable energy production. This can be realized by single-stage dark or photofermentative processes, or by a two-stage integrated process; the latter offering the higher production yields due to complete conversion of sugar substrates into H2 and CO2. However, problems arising from the integration of these two processes limit its scale-up and implementation. Hence, high efficiency one-step fermentative biohydrogen production processes from sugar-rich wastes are preferable...
November 2017: Bioprocess and Biosystems Engineering
Giorgia Pagliano, Valeria Ventorino, Antonio Panico, Olimpia Pepe
Recently, issues concerning the sustainable and harmless disposal of organic solid waste have generated interest in microbial biotechnologies aimed at converting waste materials into bioenergy and biomaterials, thus contributing to a reduction in economic dependence on fossil fuels. To valorize biomass, waste materials derived from agriculture, food processing factories, and municipal organic waste can be used to produce biopolymers, such as biohydrogen and biogas, through different microbial processes. In fact, different bacterial strains can synthesize biopolymers to convert waste materials into valuable intracellular (e...
2017: Biotechnology for Biofuels
Pretty Mori Budiman, Ta Yeong Wu, Ramakrishnan Nagasundara Ramanan, Jamaliah Md Jahim
One-time ultrasonication pre-treatment of Rhodobacter sphaeroides was evaluated for improving biohydrogen production via photofermentation. Batch experiments were performed by varying ultrasonication amplitude (15, 30, and 45%) and duration (5, 10, and 15 min) using combined effluents from palm oil as well as pulp and paper mill as a single substrate. Experimental data showed that ultrasonication at amplitude 30% for 10 min (256.33 J/mL) achieved the highest biohydrogen yield of 9.982 mL H2/mLmedium with 5...
July 2017: Environmental Science and Pollution Research International
Balaji Sundara Sekar, Eunhee Seol, Sunghoon Park
BACKGROUND: Biologically, hydrogen (H2) can be produced through dark fermentation and photofermentation. Dark fermentation is fast in rate and simple in reactor design, but H2 production yield is unsatisfactorily low as <4 mol H2/mol glucose. To address this challenge, simultaneous production of H2 and ethanol has been suggested. Co-production of ethanol and H2 requires enhanced formation of NAD(P)H during catabolism of glucose, which can be accomplished by diversion of glycolytic flux from the Embden-Meyerhof-Parnas (EMP) pathway to the pentose-phosphate (PP) pathway in Escherichia coli...
2017: Biotechnology for Biofuels
Jacqueline Xiao Wen Hay, Ta Yeong Wu, Joon Ching Juan, Jamaliah Md Jahim
Although a significant amount of brewery wastewater (BW) is generated during beer production, the nutrients in the BW could be reused as a potential bio-resource for biohydrogen production. Therefore, improvements in photofermentative biohydrogen production due to a combination of BW and pulp and paper mill effluent (PPME) as a mixed production medium were investigated comprehensively in this study. The experimental results showed that both the biohydrogen yield and the chemical oxygen demand removal were improved through the combination of BW and PPME...
April 2017: Environmental Science and Pollution Research International
R Zagrodnik, M Łaniecki
Hydrogen production from starch by a co-culture hybrid dark and photofermentation under repeated fed-batch conditions at different organic loading rates (OLR) was studied. Effective cooperation between bacteria in co-culture during initial days was observed at controlled pH 7.0. However, at pH above 6.5 dark fermentation phase was redirected from H2 formation towards production of formic acid, lactic acid and ethanol (which are not coupled with hydrogen production) with simultaneous lower starch removal efficiency...
January 2017: Bioresource Technology
Elisa Corneli, Alessandra Adessi, Federico Dragoni, Giorgio Ragaglini, Enrico Bonari, Roberto De Philippis
The present study was aimed at assessing the biotransformation of dark fermented agroindustrial residues and energy crops for the production of hydrogen and poly-β-hydroxybutyrate (PHB), in lab-scale photofermentation. The investigation on novel substrates for photofermentation is needed in order to enlarge the range of sustainable feedstocks. Dark fermentation effluents of ensiled maize, ensiled giant reed, ensiled olive pomace, and wheat bran were inoculated with Rhodopseudomonas palustris CGA676, a mutant strain suitable for hydrogen production in ammonium-rich media...
September 2016: Bioresource Technology
Anish Ghimire, Serena Valentino, Luigi Frunzo, Francesco Pirozzi, Piet N L Lens, Giovanni Esposito
This work aimed at investigating concomitant production of biohydrogen and poly-β-hydroxybutyrate (PHB) by photofermentation (PF) using dark fermentation effluents (DFE). An adapted culture of Rhodobacter sphaeroides AV1b (pH 6.5, 24±2°C) achieved H2 and PHB yields of 256 (±2) NmLH2/g Chemical Oxygen Demand (COD) and 273.8mgPHB/gCOD (32.5±3% of the dry cells weight (DCW)), respectively. When a diluted (1:2) DFE medium was applied to the adapted pure and mixed photofermentative culture, the respective H2 yields were 164...
October 2016: Bioresource Technology
Alessandra Adessi, Margherita Concato, Andrea Sanchini, Federico Rossi, Roberto De Philippis
Hydrogen represents a possible alternative energy carrier to face the growing request for energy and the shortage of fossil fuels. Photofermentation for the production of H2 constitutes a promising way for integrating the production of energy with waste treatments. Many wastes are characterized by high salinity, and polluted seawater can as well be considered as a substrate. Moreover, the application of seawater for bacterial culturing is considered cost-effective. The aims of this study were to assess the capability of the metabolically versatile freshwater Rhodopseudomonas palustris 42OL of producing hydrogen on salt-containing substrates and to investigate its salt stress response strategy, never described before...
March 2016: Applied Microbiology and Biotechnology
Lilit Gabrielyan, Harutyun Sargsyan, Armen Trchounian
BACKGROUND: Biohydrogen (H2) production by purple bacteria during photofermentation is a very promising way among biological H2 production methods. The effects of protonophores, carbonyl cyanide m-chlorophenylhydrazone (CCCP), 2,4-dinitrophenol (DNP), and inhibitors of enzymes, involved in H2 metabolism, metronidazole (Met), diphenyleneiodonium (DPI), and dimethylsulphoxide (DMSO) on H2 production by Rhodobacter sphaeroides MDC6522 isolated from Jermuk mineral springs in Armenia have been investigated in both nitrogen-limited and nitrogen-excess conditions...
2015: Microbial Cell Factories
R Zagrodnik, M Laniecki
The role of pH control on biohydrogen production by co-culture of dark-fermentative Clostridium acetobutylicum and photofermentative Rhodobacter sphaeroides was studied. Single stage dark fermentation, photofermentation and hybrid co-culture systems were studied at different values of controlled and uncontrolled pH. Increasing pH during dark fermentation resulted in lower hydrogen production rate (HPR) and longer lag time for both controlled and uncontrolled conditions. However, it only slightly affected cumulative H2 volume...
October 2015: Bioresource Technology
Basar Uyar, Muazzez Gürgan, Ebru Özgür, Ufuk Gündüz, Meral Yücel, Inci Eroglu
Photofermentative production of hydrogen is a promising and sustainable process; however, it should be coupled to dark fermentation to become cost effective. In order to integrate dark fermentation and photofermentation, the suitability of dark fermenter effluents for the photofermentative hydrogen production must be demonstrated. In this study, thermophilic dark fermenter effluent (DFE) of sugar beet thick juice was used as a substrate in photofermentation process to compare wild-type and uptake hydrogenase-deficient (hup (-)) mutant strains of Rhodobacter capsulatus by means of hydrogen production and biomass growth...
October 2015: Bioprocess and Biosystems Engineering
Rosangela Lucio Costa, Thamayne Valadares Oliveira, Juliana de Souza Ferreira, Vicelma Luiz Cardoso, Fabiana Regina Xavier Batista
The most important global demand is the energy supply from alternative source. Ethanol may be considered an environmental friendly fuel that has been produced by feedstock. The production of ethanol by microalgae represent a process with reduced environmental impact with efficient CO2 fixation and requiring less arable land. This work studied the production of ethanol from green alga Chlamydomonas reinhardtii through the cellular metabolism in a light/dark cycle at 25 °C in a TAP medium with sulfur depletion...
April 2015: Bioresource Technology
L Dipasquale, A Adessi, G d'Ippolito, F Rossi, A Fontana, R De Philippis
Two-stage process based on photofermentation of dark fermentation effluents is widely recognized as the most effective method for biological production of hydrogen from organic substrates. Recently, it was described an alternative mechanism, named capnophilic lactic fermentation, for sugar fermentation by the hyperthermophilic bacterium Thermotoga neapolitana in CO2-rich atmosphere. Here, we report the first application of this novel process to two-stage biological production of hydrogen. The microbial system based on T...
January 2015: Applied Microbiology and Biotechnology
Yuan Liu, Dipankar Ghosh, Patrick C Hallenbeck
A future hydrogen economy requires the sustainable production of renewable hydrogen. One method to produce hydrogen from stored renewable energy could be through reformation of bioethanol. However, chemically catalyzed reformation processes, although well studied, still present a number of significant technical challenges. Here, bioreformation of ethanol to hydrogen by photofermentation with the photosynthetic bacterium Rhodopseudomonas palustris is described. Cultures were shown to tolerate up to 2% ethanol...
January 2015: Bioresource Technology
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