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Yu Y, Wu YH, Zhu SF, Hu HY. The bioavailability of the soluble algal products of different microalgal strains and its influence on microalgal growth in unsterilized domestic secondary effluent. BIORESOURCE TECHNOLOGY 2015; 180:352-355. [PMID: 25608873 DOI: 10.1016/j.biortech.2014.12.065] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 12/19/2014] [Accepted: 12/20/2014] [Indexed: 06/04/2023]
Abstract
Soluble algal products (SAPs) accumulated in microalgal culture could be used as carbon source by bacteria, and thus induce serious bacteria contamination. In this study, three freshwater microalgal strains, Scenedesmus sp. LX1 (S. LX1), Chlorella ellipsoidea YJ1 (C. YJ1) and Haematococcus pluvialis (H. pluvialis), were used to investigate the bioavailability of SAPs and its influence on microalgal growth in unsterilized domestic secondary effluent. S. LX1 and H. pluvialis could grow well whether secondary effluent was sterilized or not, while C. YJ1 showed poor growth without sterilization. The assimilable organic carbon (AOC) concentration and AOC content in the SAPs of C. YJ1 was as high as 180μg-CL(-1) and 3.2%, respectively, which induced more serious bacteria contamination and thus inhibited the growth of C. YJ1. Based on the results, in microalgal strain selection for massive cultivation, AOC assays of SAPs could be applied to examine microalgal susceptibility to bacteria contamination.
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102
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Ji MK, Yun HS, Park S, Lee H, Park YT, Bae S, Ham J, Choi J. Effect of food wastewater on biomass production by a green microalga Scenedesmus obliquus for bioenergy generation. BIORESOURCE TECHNOLOGY 2015; 179:624-628. [PMID: 25553643 DOI: 10.1016/j.biortech.2014.12.053] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 12/12/2014] [Accepted: 12/15/2014] [Indexed: 06/04/2023]
Abstract
Effect of food wastewater (FW) on the biomass, lipid and carbohydrate production by a green microalga Scenedesmus obliquus cultivated in Bold's Basal Medium (BBM) was investigated. Different dilution ratios (0.5-10%) of BBM either with FW or salt solution (NaCl) or sea water (SW) were evaluated. S. obliquus showed the highest growth (0.41 g L(-1)), lipid productivity (13.3 mg L(-1) day L(-1)), carbohydrate productivity (14.7 mg L(-1) day L(-1)) and nutrient removal (38.9 mg TN L(-1) and 12.1 mg TP L(-1)) with 1% FW after 6 days of cultivation. The FW promoted algal autoflocculation due to formation of inorganic precipitates at an alkali pH. Fatty acid methyl ester analysis revealed that the palmitic and oleic acid contents were increased up to 8% with FW. Application of FW improved the growth, lipid/carbohydrate productivity and biomass recovery efficiency of S. obliquus, which can be exploited for cost effective production of microalgae biomass.
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103
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Abinandan S, Bhattacharya R, Shanthakumar S. Efficacy of Chlorella pyrenoidosa and Scenedesmus abundans for Nutrient Removal in Rice Mill Effluent (Paddy Soaked Water). INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2015; 17:377-381. [PMID: 25409251 DOI: 10.1080/15226514.2014.910167] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Microalgae are product of sustainable development owing to its ability to treat variety of wastewater effluents and thus produced biomass can serve as value added product for various commercial applications. This paper deals with the cultivation of microalgae species namely Chlorella pyrenoidosa and Scenedesmus abundans in rice mill effluent (i.e., paddy soaked water) for nutrient removal. In order to investigate the nutrient removal capability, microalgae are subjected to cultivation in both raw and autoclaved samples. The maximum phosphate removal by Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 98.3% and 97.6%, respectively, whereas, the removal of ammoniacal nitrogen by Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 92% and 90.3%, respectively. The growth (measured in terms of chlorophyll content) of Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 3.88 mg/l and 5.55 mg/l, respectively. The results indicate the suitability of microalgae cultivation in rice mill effluent treatment for nutrient removal.
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104
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Marcilhac C, Sialve B, Pourcher AM, Ziebal C, Bernet N, Béline F. Control of nitrogen behaviour by phosphate concentration during microalgal-bacterial cultivation using digestate. BIORESOURCE TECHNOLOGY 2015; 175:224-230. [PMID: 25459826 DOI: 10.1016/j.biortech.2014.10.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 10/03/2014] [Accepted: 10/05/2014] [Indexed: 06/04/2023]
Abstract
The cultivation of microalgae with digestate supernatant is a promising process for the recovery of mineralized nutrients (P, N) from anaerobic digestion. Nevertheless, the variability of phosphorus concentration in the influent could limit this process. The impact of initial N:P ratios between 3 and 76gNgP(-1) was studied and proved no growth limitation over 14-day batch experiments even when P was depleted. Nitrogen assimilation was not affected by phosphorus concentrations and reached 10.1mgNL(-1)d(-1) whereas phosphorus removal ranged from 0.6 to 2.0mgPL(-1)d(-1). The biomass N:P ratio was found to be a function of the influent N:P ratio. Phosphorus storage by microalgae was thus confirmed. Nitrification was found to be highly dependent on the initial phosphorus concentration. The evolution of microalgae communities was also monitored and revealed the advantage of Scenedesmus over Chlorella when the media was phosphorus-depleted.
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105
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Misra R, Guldhe A, Singh P, Rawat I, Stenström TA, Bux F. Evaluation of operating conditions for sustainable harvesting of microalgal biomass applying electrochemical method using non sacrificial electrodes. BIORESOURCE TECHNOLOGY 2015; 176:1-7. [PMID: 25460977 DOI: 10.1016/j.biortech.2014.11.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 11/02/2014] [Accepted: 11/04/2014] [Indexed: 06/04/2023]
Abstract
The efficient harvesting of microalgae is considered to be one of the challenging steps of algal biofuel production and a key factor limiting the commercial use of microalgae. To overcome the limitation of metallic electrodes depletion, the application of non-sacrificial electrode was investigated for the electrochemical harvesting (ECH) of microalgae. The effect of applied current, addition of electrolyte and initial pH were parameters investigated. The highest recovery efficiency of 83% was obtained for Scenedesmus obliquus at 1.5A, initial pH 9 and 6gL(-)(1) NaCl with power consumption of 3.84kWhkg(-)(1). Recovery efficiency of ECH process was comparable to literature reported centrifugation, filtration and chemical flocculation techniques but with a much lower power consumption. The ECH process with addition of electrolyte enhanced the lipid extraction by 22% without any adverse effects. The ECH process with non sacrificial carbon electrodes could be a possible harvesting step at commercial scale microalgal biomass production.
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106
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Liady MND, Tangou TT, Fiogbe ED, Cauchie HM, Vasel JL. About the interest of a zooplankton compartment in pond systems: methodology to study the growth kinetic of Daphnia pulex on Scenedesmus sp. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2015; 71:1436-1443. [PMID: 26442483 DOI: 10.2166/wst.2015.107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A reliable characterization of cladocerans' growth kinetic on their substrates is crucial for the estimation of their biochemical conversion rate in pond models. Although many studies reported cladocerans' growth inhibitions by high chlorophyceae contents, their growth kinetics had continued to be described in many pond system models by Monod-type kinetic, which describes growth saturation by high substrate contents, but fails to explain the disappearance of cladocerans observed during chlorophyceae's bloom periods. This study aimed to develop a methodology and assess whether growth-inhibition-type models used to describe microbial growth kinetics can be applicable to cladocerans. Experiments were carried out using Daphnia pulex populations and Scenedesmus sp. First, biomass of D. pulex was measured through digital image processing (DIP) during growth experiments. Then, three candidate models (i.e., Andrews, Edward and Haldane models), along with the Monod model, were fitted to the observed data and compared. The results showed that the DIP technique provided reliable results for estimating the biomass of D. pulex. Our findings show that the candidate growth inhibition-type models satisfactorily described D. pulex's growth kinetic (86% variance accounted for). Scenesdemus sp. were not strong inhibitors of the growth of D. pulex (high inhibition constant and low half-saturation constant found).
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107
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Cea-Barcia G, Moreno G, Buitrón G. Anaerobic digestion of mixed microalgae cultivated in secondary effluent under mesophilic and thermophilic conditions. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2015; 72:1398-1403. [PMID: 26465311 DOI: 10.2166/wst.2015.344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The anaerobic digestion of mixed indigenous microalgae, grown in a secondary effluent, was evaluated in batch tests at mesophilic (35°C) and thermophilic (50°C) conditions. Under mesophilic conditions, specific methane production varied from 178 to 207 mL CH4/g volatile solids (VS) and the maximum production rate varied from 8.8 to 26.1 mL CH4/(gVS day), depending on the type of microalgae culture. Lower methane parameters were observed in those cultures where Scenedesmus represents more than 95% of the microalge. The culture with the lowest digestion performances under mesophilic conditions was studied under thermophilic conditions. The increase in the incubation temperature significantly increased the specific methane production (390 mL CH4/g VS) and rate (26.0 mL CH4/(gVS day)). However, under thermophilic conditions a lag period of 30 days was observed.
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108
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González-Garcinuño Á, Tabernero A, Sánchez-Álvarez JM, Martin Del Valle EM, Galán MA. Effect of nitrogen source on growth and lipid accumulation in Scenedesmus abundans and Chlorella ellipsoidea. BIORESOURCE TECHNOLOGY 2014; 173:334-341. [PMID: 25310870 DOI: 10.1016/j.biortech.2014.09.038] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 09/03/2014] [Accepted: 09/06/2014] [Indexed: 06/04/2023]
Abstract
Discovering microalgae strains containing a high lipid yield and adequate fatty acid composition is becoming a crucial fact in algae-oil factories. In this study, two unknown strains, named Scenedesmus abundans and Chlorella ellipsoidea, have been tested for their response to different nitrogen sources, in order to determine its influence in the production of lipids. For S. abundans, autotrophic culture with ammonium nitrate offers the maximum lipid yield, obtaining up to 3.55 mg L(-1) d(-1). For C. ellipsoidea, heterotrophic culture with ammonium nitrate has been shown to be the best condition, reaching a lipid production of 9.27 mg L(-1) d(-1). Moreover, fatty acid composition obtained from these cultures meets international biodiesel standards with an important amount of C18:1, achieving 70% of total fatty acids and thus representing a potential use of these two strains at an industrial scale.
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109
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Feng P, Yang K, Xu Z, Wang Z, Fan L, Qin L, Zhu S, Shang C, Chai P, Yuan Z, Hu L. Growth and lipid accumulation characteristics of Scenedesmus obliquus in semi-continuous cultivation outdoors for biodiesel feedstock production. BIORESOURCE TECHNOLOGY 2014; 173:406-414. [PMID: 25444884 DOI: 10.1016/j.biortech.2014.09.123] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 09/22/2014] [Accepted: 09/23/2014] [Indexed: 06/04/2023]
Abstract
In an effort to identify suitable microalgal species for biodiesel production, seven species were isolated from various habitats and their growth characteristics were compared. The results demonstrated that a green alga Scenedesmus obliquus could grow more rapidly and synthesize more lipids than other six microalgal strains. S. obliquus grew well both indoors and outdoors, and reached higher μmax indoors than that outdoors. However, the cells achieved higher dry weight (4.36 g L(-1)), lipid content (49.6%) and productivity (183 mg L(-1) day(-1)) outdoors than in indoor cultures. During the 61 days semi-continuous cultivation outdoors, high biomass productivities (450-550 mg L(-1) day(-1)) and μmax (1.05-1.44 day(-1)) were obtained. The cells could also achieve high lipid productivities (151-193 mg L(-1) day(-1)). These results indicated that S. obliquus was promising for lipids production in semi-continuous cultivation outdoors.
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110
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Zhang C, Zhang Y, Zhuang B, Zhou X. Strategic enhancement of algal biomass, nutrient uptake and lipid through statistical optimization of nutrient supplementation in coupling Scenedesmus obliquus-like microalgae cultivation and municipal wastewater treatment. BIORESOURCE TECHNOLOGY 2014; 171:71-79. [PMID: 25189511 DOI: 10.1016/j.biortech.2014.07.060] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 07/14/2014] [Accepted: 07/16/2014] [Indexed: 06/03/2023]
Abstract
Supplementing proper nutrients could be a strategy for enhancing algal biomass, nutrients uptake and lipid accumulation in the coupling system of biodiesel production and municipal wastewater treatment. However, there is scant information reporting systematic studies on screening and optimization of key supplemented components in the coupling system. The main factors were scientifically screened and optimized using statistical methods. Plackett-Burman design (PBD) was used to explore the roles of added nutrient factors, whereas response surface methodology (RSM) was employed for optimization. Based on the statistic analysis, the optimum added TP and FeCl3·6H2O concentrations for Scenedesmus obliquus-like microalgae growth, nutrients uptake and lipid accumulation were 4.41 mg L(-1) and 6.48 mg L(-1), respectively. The corresponding biomass, lipid content and TN/TP removal efficiency were 1.46 g L(-1), 36.26% and >99%. The predicted value agreed well with the experimental value, as determined by validation experiments, which confirmed the availability and accuracy of the model.
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111
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Marcilhac C, Sialve B, Pourcher AM, Ziebal C, Bernet N, Béline F. Digestate color and light intensity affect nutrient removal and competition phenomena in a microalgal-bacterial ecosystem. WATER RESEARCH 2014; 64:278-287. [PMID: 25078443 DOI: 10.1016/j.watres.2014.07.012] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 05/21/2014] [Accepted: 07/06/2014] [Indexed: 06/03/2023]
Abstract
During anaerobic digestion, nutrients are mineralized and may require post-treatment for optimum valorization. The cultivation of autotrophic microalgae using the digestate supernatant is a promising solution; however the dark color of the influent poses a serious problem. First, the color of the digestates was studied and the results obtained using three different digestates demonstrated a strong heterogeneity although their color remained rather constant over time. The digestates absorbed light over the whole visible spectrum and remained colored even after a ten-fold dilution. Secondly, the impact of light and of substrate color on the growth of Scenedesmus sp. and on nitrogen removal were assessed. These experiments led to the construction of a model for predicting the impact of influent color and light intensity on N removal. Maximum N removal (8.5 mgN- [Formula: see text] L(-1) d(-1)) was observed with an initial optical density of 0.221 and 244 μmolE m(-)² s(-1) light and the model allows to determine N removal between 15.9 and 22.7 mgN- [Formula: see text] L(-1) d(-1) in real conditions according to the dilution level of the influent and related color. Changes in the microalgae community were monitored and revealed the advantage of Chlorella over Scenedesmus under light-limitation. Additionally microalgae outcompeted nitrifying bacteria and experiments showed how microalgae become better competitors for nutrients when phosphorus is limiting. Furthermore, nitrification was limited by microalgae growth, even when P was not limiting.
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112
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Salama ES, Kabra AN, Ji MK, Kim JR, Min B, Jeon BH. Enhancement of microalgae growth and fatty acid content under the influence of phytohormones. BIORESOURCE TECHNOLOGY 2014; 172:97-103. [PMID: 25247249 DOI: 10.1016/j.biortech.2014.09.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 08/30/2014] [Accepted: 09/02/2014] [Indexed: 05/03/2023]
Abstract
The growth of Scenedesmus obliquus improved with increase in phytohormones concentrations (10(-8)-10(-)(5)M). Indole-3-acetic acid (IAA) supported the maximum growth at 10(-5)M with 17.7×10(6)cells/mL and total fatty acid of 97.9mg/g-DCW, enhancing the growth by 1.9-fold compared to control (9.5×10(6)cells/mL). While 10(-5)M of a newly discovered phytohormone Diethyl aminoethyl hexanoate (DAH) demonstrated a 2.5-fold higher growth with 23.5×10(6)cells/mL and a total fatty acid content of 100mg/g-DCW. Poly-unsaturated fatty acid content increased up to 56% and 59% at 10(-)(5)M of IAA and DAH, respectively. The highest carbohydrate content (33% and 34%) achieved at 10(-8)M and 10(-5)M of IAA and DAH, respectively. While, the highest protein content (34% and 35%) obtained at 10(-8)M of IAA and DAH, respectively. The current investigation demonstrates that phytohormones accelerate microalgal growth and induce the quality and quantity of fatty acid content for biodiesel production.
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113
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Ren HY, Liu BF, Kong F, Zhao L, Xie GJ, Ren NQ. Enhanced lipid accumulation of green microalga Scenedesmus sp. by metal ions and EDTA addition. BIORESOURCE TECHNOLOGY 2014; 169:763-767. [PMID: 25037828 DOI: 10.1016/j.biortech.2014.06.062] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 06/16/2014] [Accepted: 06/18/2014] [Indexed: 05/12/2023]
Abstract
Effects of Fe(3+) (0-0.12 g/L), Mg(2+) (0-0.73 g/L) and Ca(2+) (0-0.98 g/L) on the biomass and lipid accumulation of heterotrophic microalgae were investigated in dark environment. The biomass and lipid production exhibited an increasing trend with increasing the concentrations of metal ions. In cultures with 1.2 × 10(-3) g/L Fe(3+), 7.3 × 10(-3) g/L Mg(2+) and 9.8 × 10(-4) g/L Ca(2+), the maximum biomass, total lipid content and lipid productivity reached 3.49 g/L, 47.4% and 275.7 mg/L/d, respectively. More importantly, EDTA addition (1.0 × 10(-3) g/L) could enhance the solubility of metal ions (iron and calcium) and increase their availability by microalgae, which evidently promote the lipid accumulation. Compared with the control, the total lipid content and lipid productivity increased 28.2% and 29.7%, respectively. These show that appropriate concentrations of metal ions and EDTA in the culture medium were beneficial to lipid accumulation of heterotrophic Scenedesmus sp. cells.
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114
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Schoepp NG, Stewart RL, Sun V, Quigley AJ, Mendola D, Mayfield SP, Burkart MD. System and method for research-scale outdoor production of microalgae and cyanobacteria. BIORESOURCE TECHNOLOGY 2014; 166:273-281. [PMID: 24926599 DOI: 10.1016/j.biortech.2014.05.046] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 05/05/2014] [Accepted: 05/07/2014] [Indexed: 06/03/2023]
Abstract
Eukaryotic microalgae and cyanobacteria have recently reemerged as promising organisms in the effort to develop sustainable options for production of food and fuel. However, substantial discrepancies consistently arise between laboratory and outdoor cultivation, and gains demonstrated using laboratory technologies have not paralleled gains observed in field demonstrations. For these reasons, a low-maintenance system and process for research-scale outdoor cultivation of a variety of both freshwater and marine microalgae and cyanobacteria was developed. Nine genera were evaluated in the system, demonstrating cultivation of both laboratory model and commercial-production organisms. Hundreds to thousands of grams of dry biomass could be produced in a single growth cycle, suitable for a variety of uses including inoculum generation, protein production, and biofuel applications. Following testing in outdoor stock-ponds, Scenedesmus and Nannochloropsis were grown semi-continuously in an 8000 L airlift-driven raceway, yielding in total over 8 kg of dry biomass for each strain.
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115
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Agbakpe M, Ge S, Zhang W, Zhang X, Kobylarz P. Algae harvesting for biofuel production: influences of UV irradiation and polyethylenimine (PEI) coating on bacterial biocoagulation. BIORESOURCE TECHNOLOGY 2014; 166:266-272. [PMID: 24926598 DOI: 10.1016/j.biortech.2014.05.060] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 05/15/2014] [Accepted: 05/17/2014] [Indexed: 06/03/2023]
Abstract
There is a pressing need to develop efficient and sustainable separation technologies to harvest algae for biofuel production. In this work, two bacterial species (Escherichia coli and Rhodococus sp.) were used as biocoagulants to harvest Chlorella zofingiensis and Scenedesmus dimorphus. The influences of UV irradiation and polyethylenimine (PEI)-coating on the algal harvesting efficiency were investigated. Results showed that the UV irradiation could slightly enhance bacteria-algae biocoagulation and algal harvesting efficiency. In contrast, the PEI-coated E. coli cells noticeably increased the harvesting efficiencies from 23% to 83% for S. dimorphus when compared to uncoated E. coli cells. Based on the soft-particle Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, an energy barrier existed between uncoated E. coli cells and algal cells, whereas the PEI coating on E. coli cells eliminated the energy barrier, thereby the biocoagulation was significantly improved. Overall, this work presented groundwork toward the potential use of bacterial biomass for algal harvesting from water.
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116
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Basu S, Roy AS, Mohanty K, Ghoshal AK. CO2 biofixation and carbonic anhydrase activity in Scenedesmus obliquus SA1 cultivated in large scale open system. BIORESOURCE TECHNOLOGY 2014; 164:323-330. [PMID: 24865325 DOI: 10.1016/j.biortech.2014.05.017] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 05/03/2014] [Accepted: 05/05/2014] [Indexed: 06/03/2023]
Abstract
The present study deals with the large scale open system cultivation of the novel microalga: Scenedesmus obliquus SA1 (KC733762) previously isolated in our laboratory. SA1 strain was cultivated in open system at varying CO2 levels ranging from 0.03% to 35% (v/v) and subsequently the carbonic anhydrase activity (CA) and the biochemical properties were monitored. Maximum biomass concentration (1.39 ± 0.023 g L(-1)), CO2 fixation rate (97.65 ± 1.03 mg L(-1)d(-1)) and total CA activity (166.86 ± 3.30 E.U./mg chla) were obtained at 35% CO2. CA inhibitors: acetazolamide and ethoxyzolamide inhibited the external and internal enzyme activity in SA1. High CO2 levels were favorable for the accumulation of lipids and chlorophyll. The present results suggested that SA1 possessed high CO2 tolerance and high carbohydrate, lipid and chlorophyll content when cultivated in open system thus being suitable for CO2 mitigation in outdoor ponds and subsequent generation of value added products.
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117
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Zhang W, Xiong B, Sun WF, An S, Lin KF, Guo MJ, Cui XH. Acute and chronic toxic effects of bisphenol A on Chlorella pyrenoidosa and Scenedesmus obliquus. ENVIRONMENTAL TOXICOLOGY 2014; 29:714-722. [PMID: 22887798 DOI: 10.1002/tox.21806] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2012] [Revised: 07/19/2012] [Accepted: 07/21/2012] [Indexed: 06/01/2023]
Abstract
The acute and chronic toxic effects of Bisphenol A (BPA) on Chlorella pyrenoidosa (C. pyrenoidosa) and Scenedesmus obliquus (S. obliquus) were not well understood. The indoor experiments were carried out to observe and analyze the BPA-induced changes. Results of the observations showed that in acute tests BPA could significantly inhibit the growth of both algae, whereas chronic exposure hardly displayed similar trend. Superoxide dismutase (SOD) and Catalase (CAT) activities of both algae were promoted in all the treatments. Chlorophyll a synthesis of the two algae exhibited similar inhibitory trend in short-term treatments, and in chronic tests C. pyrenoidosa hardly resulted in visible influence, whereas in contrast, dose-dependent inhibitory effects of S. obliquus could be clearly observed. The experimental results indicated that the growth and Chlorophyll a syntheses of S.obliquus were more sensitive in response to BPA than that of C. pyrenoidosa, whereas for SOD andCAT activities, C. pyrenoidosa was more susceptible. This research provides a basic understanding of BPA toxicity to aquatic organisms.
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118
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Guerrero-Cabrera L, Rueda JA, García-Lozano H, Navarro AK. Cultivation of Monoraphidium sp., Chlorella sp. and Scenedesmus sp. algae in Batch culture using Nile tilapia effluent. BIORESOURCE TECHNOLOGY 2014; 161:455-460. [PMID: 24736090 DOI: 10.1016/j.biortech.2014.03.127] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2014] [Revised: 03/20/2014] [Accepted: 03/23/2014] [Indexed: 06/03/2023]
Abstract
Monoraphidium sp., Chlorella sp. and Scenedesmus sp. algae were cultured in three volumes of Tilapia Effluent Medium (TEM) in comparison with the Bold Basal Medium (BBM) (Nichols and Bold, 1965). Specific growth rate (μ'), biomass dry productivity (Q), volumetric productivity (Qv) as well as lipid and protein content were measured. Then, volumetric productivities for both lipids and proteins were calculated (QVL and QVP). In Scenedesmus sp., BBM produced higher μ' and Qv than TEM in 1.5L volume. Chlorella sp. showed a higher QVL for BBM than TEM. Any observed difference in protein or lipid productivities among volumes was in favor of a greater productivity for 1.5L volume. Even when TEM had a larger protein content in Chlorella sp. than BBM, QVP was not different. Current results imply that TEM can be used as an alternative growth medium for algae when using Batch cultures, yet productivity is reduced.
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119
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Song M, Pei H, Hu W, Zhang S, Ma G, Han L, Ji Y. Identification and characterization of a freshwater microalga Scenedesmus SDEC-8 for nutrient removal and biodiesel production. BIORESOURCE TECHNOLOGY 2014; 162:129-135. [PMID: 24747391 DOI: 10.1016/j.biortech.2014.03.135] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2014] [Revised: 03/21/2014] [Accepted: 03/24/2014] [Indexed: 06/03/2023]
Abstract
The selection of the right strains is of fundamental important to the success of the algae-based oil industry. From the six newly isolated microalgae strains tested for growth, fatty acid methyl ester (FAME) profiles and biodiesel properties, Scenedesmus SDEC-8, with favorable C16:0 fatty acids (73.43%), showed the best combined results. Then, morphological and molecular identification were examined. From the three wastewaters samples, Scenedesmus SDEC-8 showed good ability to yield oil and remove nutrients, which were comparable with other reports. In b artificial wastewater (TN 40 mg L(-1), TP 8 mg L(-1)), Scenedesmus SDEC-8 achieved the highest value of lipid productivity (53.84 mg L(-1) d(-1)), MUFA content (35.35%) and total FAME content (59.57±0.02 mg g(-1) DW), besides higher removal efficiencies of TN (99.18%) and TP (98.86%) helped effluent directly discharge and smaller dilution factor of N, P (3.3 and 9) which was good for lessening water utilization.
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Chen BY, Chen CY, Guo WQ, Chang HW, Chen WM, Lee DJ, Huang CC, Ren NQ, Chang JS. Fixed-bed biosorption of cadmium using immobilized Scenedesmus obliquus CNW-N cells on loofa (Luffa cylindrica) sponge. BIORESOURCE TECHNOLOGY 2014; 160:175-181. [PMID: 24581862 DOI: 10.1016/j.biortech.2014.02.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 01/29/2014] [Accepted: 02/01/2014] [Indexed: 06/03/2023]
Abstract
A continuous fixed-bed biosorption process was established for cadmium (Cd) removal by Scenedesmus obliquus CNW-N (isolated from southern Taiwan) cells immobilized onto loofa sponge. This immobilized-cell biosorption process allows better recovery and reusability of the microalgal biomass. The growth of microalgae on the matrix support with appropriate nutrient supplementation could enhance the overall metal removal activity. Major operating parameters (e.g., feeding flow rate, cycle number of medium replacement, and particle diameter of the sponge) were studied for treatability evaluation. The most promising cell growth on the sponge support was obtained at a flow rate of 0.284 bed volume (BV)/min, sponge particle diameter of 1 cm, and with one cycle of medium replacement. The performance of fixed-bed biosorption (adsorption capacity of 38.4 mg, breakthrough time at 15.5 h) was achieved at a flow rate of 5 ml/min with an influent concentration of 7.5 mg Cd/l.
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Hu C, Luo Q, Huang Q. Ecotoxicological effects of perfluorooctanoic acid on freshwater microalgae Chlamydomonas reinhardtii and Scenedesmus obliquus. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2014; 33:1129-1134. [PMID: 24464740 DOI: 10.1002/etc.2532] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 01/02/2014] [Accepted: 01/16/2014] [Indexed: 06/03/2023]
Abstract
As a persistent bioaccumulative compound, perfluorooctanoic acid (PFOA) is found in various ecosystems and receives growing attention. The acute toxicity of PFOA was tested on 2 freshwater microalgae, Chlamydomonas reinhardtii and Scenedesmus obliquus. The 96-h concentration for 50% of maximal effect (EC50) values were measured, physiological responses of the algae were investigated, and uptake of PFOA by the algae was quantified. The EC50 values for C. reinhardtii and S. obliquus were 51.9 ± 1.0 mg/L and 44.0 ± 1.5 mg/L PFOA, respectively. After 8-d exposure to PFOA ranging from 10 mg/L to 40 mg/L, the growth of C. reinhardtii was significantly inhibited, whereas that of S. obliquus was only slightly suppressed. Increases in malonaldehyde and proline levels were observed in the 2 algae when exposed to PFOA at certain concentrations, for instance, 20 mg/L and 40 mg/L, which is indicative of the trigger of a defensive mechanism. The percentage of PFOA that was adsorbed by the algae after 8-d exposure at a dosage between 5 mg/L and 20 mg/L ranged from 5.5% to 7.5%, and the uptake of PFOA by the algae exceeded 10%.
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Ometto F, Pozza C, Whitton R, Smyth B, Gonzalez Torres A, Henderson RK, Jarvis P, Jefferson B, Villa R. The impacts of replacing air bubbles with microspheres for the clarification of algae from low cell-density culture. WATER RESEARCH 2014; 53:168-179. [PMID: 24525066 DOI: 10.1016/j.watres.2014.01.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 01/07/2014] [Accepted: 01/08/2014] [Indexed: 06/03/2023]
Abstract
Dissolved Air Flotation (DAF) is a well-known coagulation-flotation system applied at large scale for microalgae harvesting. Compared to conventional harvesting technologies DAF allows high cell recovery at lower energy demand. By replacing microbubbles with microspheres, the innovative Ballasted Dissolved Air Flotation (BDAF) technique has been reported to achieve the same algae cell removal efficiency, while saving up to 80% of the energy required for the conventional DAF unit. Using three different algae cultures (Scenedesmus obliquus, Chlorella vulgaris and Arthrospira maxima), the present work investigated the practical, economic and environmental advantages of the BDAF system compared to the DAF system. 99% cells separation was achieved with both systems, nevertheless, the BDAF technology allowed up to 95% coagulant reduction depending on the algae species and the pH conditions adopted. In terms of floc structure and strength, the inclusion of microspheres in the algae floc generated a looser aggregate, showing a more compact structure within single cell alga, than large and filamentous cells. Overall, BDAF appeared to be a more reliable and sustainable harvesting system than DAF, as it allowed equal cells recovery reducing energy inputs, coagulant demand and carbon emissions.
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Ren HY, Liu BF, Kong F, Zhao L, Xing D, Ren NQ. Enhanced energy conversion efficiency from high strength synthetic organic wastewater by sequential dark fermentative hydrogen production and algal lipid accumulation. BIORESOURCE TECHNOLOGY 2014; 157:355-359. [PMID: 24582427 DOI: 10.1016/j.biortech.2014.02.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2014] [Revised: 02/01/2014] [Accepted: 02/03/2014] [Indexed: 06/03/2023]
Abstract
A two-stage process of sequential dark fermentative hydrogen production and microalgal cultivation was applied to enhance the energy conversion efficiency from high strength synthetic organic wastewater. Ethanol fermentation bacterium Ethanoligenens harbinense B49 was used as hydrogen producer, and the energy conversion efficiency and chemical oxygen demand (COD) removal efficiency reached 18.6% and 28.3% in dark fermentation. Acetate was the main soluble product in dark fermentative effluent, which was further utilized by microalga Scenedesmus sp. R-16. The final algal biomass concentration reached 1.98gL(-1), and the algal biomass was rich in lipid (40.9%) and low in protein (23.3%) and carbohydrate (11.9%). Compared with single dark fermentation stage, the energy conversion efficiency and COD removal efficiency of two-stage system remarkably increased 101% and 131%, respectively. This research provides a new approach for efficient energy production and wastewater treatment using a two-stage process combining dark fermentation and algal cultivation.
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Kang J, Wang T, Xin H, Wen Z. A laboratory study of microalgae-based ammonia gas mitigation with potential application for improving air quality in animal production operations. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2014; 64:330-339. [PMID: 24701691 DOI: 10.1080/10962247.2013.859185] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
UNLABELLED Ammonia gas emission is a major concern in concentrated animal production operations. It not only reduces the manure value as fertilizer due to nitrogen loss, but also has considerable environmental consequences for both animals and ecosystem. In this work, a microalgae culture system was developed as an ammonia gas bioscrubber to reduce ammonia gas emission. The green algae Scenedesmus dimorphus was grown in a flat-panel photobioreactor aerated with ammonia-laden air. A continuous culture was performed at different operational conditions including dilution rate (D = 0.05, 0.1, 0.2, and 0.3 day(-1)), ammonia gas loading rate (9.4, 19.3, 28.9, 39.9, 55.6 mg/L-day), and medium pH (5, 6, 7, and 8). The alga culture at 0.1 day(-1) dilution rate, 39.9 mg/L-day ammonia gas loading rate, and pH 7 resulted in the highest cell density and biomass productivity. In order to provide a wide spectrum evaluation of the algae-based ammonia mitigation system, four parameters were determined, including ammonia removal rate, overall ammonia gas removal efficiency, cellular ammonia consumption rate, and cell yield based on ammonia input. Depending on the operational conditions used, the maximum values of those four evaluative parameters were 50.92 +/- 2.91 mg/L-day of ammonia removal rate, 94.90 +/- 1.87% of ammonia removal efficiency, 0.0597 +/- 0.0024 g NH3/g cell-day of cellular ammonia consumption rate, and 19.40 +/- 2.52 g cell/g NH3 of cell yield based on ammonia. It was also found that the majority of nitrogen in the ammonia gas was assimilated by the algal cells. At D = 0.1 day(-1), 39.9 mg/L-day of ammonia gas loading rate and pH 7, algal biomass assimilated 98.6% of nitrogen contained in the ammonia gas input, with less than 5% of inlet ammonia gas was exhausted after the algal treatment. IMPLICATIONS This study demonstrated the effectiveness of using microalgae for mitigating ammonia gas emission from animal production operations. The results enabled us to better understand the mechanisms of ammonia assimilation by microalgae, the engineering design parameters for the process scale up, and the economic viability of the system. Eventually, it will lead to a novel, alternative method for mitigating ammonia gas emission from concentrated animal operations while producing biomass as high-quality feed ingredient.
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Mandotra SK, Kumar P, Suseela MR, Ramteke PW. Fresh water green microalga Scenedesmus abundans: A potential feedstock for high quality biodiesel production. BIORESOURCE TECHNOLOGY 2014; 156:42-47. [PMID: 24486936 DOI: 10.1016/j.biortech.2013.12.127] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 12/28/2013] [Accepted: 12/31/2013] [Indexed: 06/03/2023]
Abstract
Present investigation studied the potential of fresh water green microalga Scenedesmus abundans as a feedstock for biodiesel production. To study the biomass and lipid yield, the culture was grown in BBM, Modified CHU-13 and BG-11 medium. Among the tested nitrogen concentration using Modified CHU-13 medium, the highest biomass and lipid yield of 1.113±0.05g/L and 489±23mg/L respectively was found in the culture medium with 0.32g/L of nitrogen (KNO3). Different lipid extraction as well as transesterification methods were also tested. Fatty acid profile of alga grown in large scale indigenous made photobioreactor has shown abundance of fatty acids with carbon chain length of C16 and C18. Various biodiesel properties such as cetane number, iodine value and saponification value were found to be in accordance with Brazilian National Petroleum Agency (ANP255) and European biodiesel standard EN14214 which makes S. abundans as a potential feedstock for biodiesel production.
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