scholarly journals Screening of Industrial Wastewaters as Feedstock for the Microbial Production of Oils for Biodiesel Production and High-Quality Pigments

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Teresa Schneider ◽  
Simone Graeff-Hönninger ◽  
William Todd French ◽  
Rafael Hernandez ◽  
Wilhelm Claupein ◽  
...  
Keyword(s):  
Fruit Juice ◽  
Low Cost ◽  
Lipid Production ◽  
Rhodotorula Glutinis ◽  
Biodiesel Production ◽  
Carotenoid Content ◽  
Plant Oil ◽  
Available Nitrogen ◽  
Carotenoid Production ◽  
Economic Constraints

The production of biodiesel has notably increased over the past decade. Currently, plant oil is the main feedstock for biodiesel production, but, due to concerns related to the competition with food production, alternative oil feedstocks have to be found. Oleaginous yeasts are known to produce high amounts of lipids, but no integrated process from microbial fermentation to final biodiesel production has reached commercial realization yet due to economic constraints. Therefore, growth and lipid production of red yeastRhodotorula glutiniswas tested on low-cost substrates, namely, wastewaters from potato, fruit juice, and lettuce processing. Additionally, the production of carotenoids as high-value by-products was examined. All evaluated wastewaters met the general criteria for microbial lipid production. However, no significant increase in lipid content was observed, probably due to lack of available carbon in wastewaters from fruit juice and lettuce processing, and excess of available nitrogen in potato processing wastewater, respectively. During growth on wastewaters from fruit juice and lettuce processing the carotenoid content increased significantly in the first 48 hours. The relations between carbon content, nitrogen content, and carotenoid production need to be further assessed. For economic viability, lipid and carotenoid production needs to be increased significantly. The screening of feedstocks should be extended to other wastewaters.

scholarly journals Lipid Production by <i>Rhodotorula glutinis</i> from Pulp and Paper Wastewater for Biodiesel Production

2015 ◽  
Vol 05 (03) ◽  
pp. 114-125 ◽  
Author(s):  
Marta Amirsadeghi ◽  
Sara Shields-Menard ◽  
W. Todd French ◽  
Rafael Hernandez
Keyword(s):  
Lipid Production ◽  
Rhodotorula Glutinis ◽  
Pulp And Paper ◽  
Biodiesel Production ◽  
Paper Wastewater

scholarly journals Optimization media from low-cost nutrient sources for growing Spirulina platensis and carotenoid production Optimasi media dengan sumber nutrisi murah untuk pertumbuhan dan produksi karotenoid Spirulina platensis

2016 ◽  
Vol 69 (1) ◽  
Author(s):  
. TRI-PANJI ◽  
. SUHARYANTO
Keyword(s):  
Bioactive Compounds ◽  
Spirulina Platensis ◽  
Low Cost ◽  
Carotenoid Content ◽  
Media Composition ◽  
Organic Complex ◽  
Nutrient Sources ◽  
Carotenoid Production ◽  
Reference Medium ◽  
Tlc Analysis

SummarySpirulina platensis is a cyanobacteriaproducing several bioactive compounds such ascarotenoids which are economically valuable. Toproduce carotenoids in S. platensis biomassefficiently, it is necessary to define an optimummedium composition consisting of mineral saltand organic complex derived from low-costnutrient sources. Spirulina platensis grown oncomplex media containing latex serum fromconcentrated latex factory, supplemented withsalt minerals might produce high yieldingcarotenoids. The objective of this research is todefine media composition for optimum growthand carotenoid production of S. platensis and toidentify carotenoid compounds from biomass ofthe algae. S. platensis was grown on mediacontaining latex serum from latex concentratefactory (5%, v/v), macroelements andmicroelements, for 10 weeks at a room aeratedand illuminated by 20 W TL lamp at 50 cmdistance. Microelements were formulatedat a certain amount to give eleven combinationsof C: N: P: Mg. The Aiba & Ogawa syntheticmedium was used as a reference medium. Theoptimum growth of S. platensis had reachedafter eight-week incubation. Among elevenmedia composition containing latex serumexamined, best growth on a formulated mediumwith a ratio of C: N: P: Mg = 1:3:0.3:0.2 yielding0.350 g biomass/L This amount was slightlylesser than those on synthetic Aiba & Ogawamedium that yields 0.407 g biomass/L, aftereight-week incubation. Although the biomassproduction was lower than that of synthetic Aiba & Ogawa medium, the formulated mediagave higher carotenoid content. The highestcarotenoid content in biomass was 2.866 mg/kgbiomass obtained from a medium with ratio ofC: N: P: Mg = 1: 2: 0.3: 0. Thin layerchromatography (TLC) analysis of biomassextract showed the presence of two-six carotenoidcompounds, in which one of them is β- carotene.RingkasanSpirulina platensis adalah sianobakteria yangmenghasilkan berbagai senyawa bioaktif bernilaiekonomi tinggi antara lain karotenoida. Untukmemproduksi karotenoida dari biomassa selS. platensis secara efisien, perlu ditetapkankomposisi media mineral dan bahan organikkompleks yang optimal dari sumber nutrisi yangmurah. Spirulina platensis yang ditumbuhkandalam media serum lateks dari pabrik latekspekat dengan suplemen garam-garam mineraltertentu diharapkan produktif dalammenghasilkan karotenoida. Tujuan penelitianadalah menetapkan komposisi media yangoptimal untuk pertumbuhan dan produksikarotenoid serta mengidentifikasi jenis senyawakarotenoid dalam biomassa sel S. platensis.Sianobakteria ini ditumbuhkan dalam mediakompleks mengandung serum lateks pekat(5%, v/v) dengan suplemen nutrisi berupamakronutrien dan mikronutrien selama10 minggu di dalam ruangan dengan aerasi danpenyinaran lampu TL 20 W pada jarak 50 cm.Komposisi makronutrien diformulasi untukmemberikan sebelas macam variasi nisbahC:N:P:Mg. Sebagai pembanding digunakanmedia sintetik Aiba & Ogawa. Hasil penelitianmenunjukkan bahwa pertumbuhan S. platensismencapai puncak setelah diinkubasikan selamadelapan minggu. Dari 11 komposisi mediamengandung lateks yang diuji, pertumbuhanS. platensis terbaik adalah yang ditumbuhkandalam media formula dengan nisbah C:N:P:Mg=1:3:0.3:0.2 menghasilkan 0,350 g biomassa/L,sedikit lebih rendah dibandingkan denganmenggunakan media sintetik Aiba & Ogawa yangmenghasilkan 0,407 g biomassa/L selama8 minggu. Walaupun kandungan biomassanyalebih rendah, media formula tersebut meng-hasilkan karotenoid lebih tinggi dibandingkandengan media sintetik Aiba & Ogawa.Kandungan karotenoid tertinggi pada biomassayaitu sebesar 2.866 mg/kg diperoleh pada mediadengan nisbah C:N:P:Mg=1:2:0.3:0. Analisisekstrak biomassa dengan TLC menunjukkanadanya dua-enam jenis karotenoida, salahsatunya adalah β - karotena.

scholarly journals Lab-scale assessment and adaptation of wastewater for cultivation of microalgal biomass for biodiesel production

2015 ◽  
Author(s):  
◽  
Luveshan Ramanna
Keyword(s):  
Large Scale ◽  
Physiological Stress ◽  
Lipid Production ◽  
Domestic Wastewater ◽  
Potassium Nitrate ◽  
Wastewater Effluent ◽  
Biodiesel Production ◽  
Available Nitrogen ◽  
Microalgal Biomass ◽  
Microalgal Culture

In light of the world’s declining fossil fuel reserves, the use of microalgal biodiesel has come to the forefront as a potentially viable alternative liquid fuel. The depleting freshwater reserves make the feasibility of this concept questionable. The use of wastewater reduces the requirement for depleting freshwater supplies. This project aimed to determine the viability of municipal domestic wastewater effluent as a substrate for microalgal growth, in order to generate an economical and environmentally friendly source of biofuel. Wastewater effluents from three domestic wastewater treatment plants were characterized in terms of known microalgal nutrients viz., ammonia, phosphate and nitrates. Phosphate concentrations varied throughout the year and were found to be low (< 3 mgL-1) whilst ammonia and nitrate concentrations ranged from 0 to 10 mgL-1 throughout the experimental period. These wastewaters were found to be suitable for cultivating microalgae. The study explored the cultivation of Chlorella sorokiniana on pre- and post-chlorinated domestic wastewater effluent to assess their potential as a medium for high microalgal culture density and lipid production. Post-chlorinated wastewater effluent was found to be superior to pre-chlorinated wastewater effluent, as evident by the higher biomass concentration. This wastewater stream did not contain high concentrations of bacteria when compared to pre-chlorinated wastewater effluent. Nitrogen is an essential nutrient required for regulating the growth and lipid accumulation in microalgae. Cultures growing in post-chlorinated effluent had a lifespan of 18 d. Residual nitrogen in wastewater effluent supported microalgal growth for limited periods. Supplementation using cheap, readily available nitrogen sources was required for optimal biomass and lipid production. Urea, potassium nitrate, sodium nitrate and ammonium nitrate were evaluated in terms of biomass and lipid production of C. sorokiniana. Urea showed the highest biomass yield of 0.216 gL-1 and was selected for further experimentation. Urea concentrations (0–10 gL-1) were assessed for their effect on growth and microalgal physiology using pulse amplitude modulated fluorometry. A concentration of 1.5 gL-1 urea produced 0.218 gL-1 biomass and 61.52 % lipid by relative fluorescence. Physiological stress was evident by the decrease in relative Electron Transport Rate from 10.45 to 6.77 and quantum efficiency of photosystem II charge separation from 0.665 to 0.131. Gas chromatography analysis revealed that C16:0, C18:0, C18:1, C18:2 and C18:3 were the major fatty acids produced by C. sorokiniana. Wastewater effluent has been considered an important resource for economical and sustainable microalgal biomass/lipid production. The study showed that C. sorokiniana was sufficiently robust to be cultivated on wastewater effluent supplemented with urea. The results indicate that supplemented wastewater effluent was an acceptable alternative to conventional media. Using a relatively cheap nitrogen source like urea can certainly improve the techno-economics of large scale biodiesel production.

scholarly journals Nitrogen Deficiency-Dependent Abiotic Stress Enhances Carotenoid Production in Indigenous Green Microalga Scenedesmus rubescens KNUA042, for Use as a Potential Resource of High Value Products

2020 ◽  
Vol 12 (13) ◽  
pp. 5445
Author(s):  
Seung-Woo Jo ◽  
Ji Won Hong ◽  
Jeong-Mi Do ◽  
Ho Na ◽  
Jin-Ju Kim ◽  
...  
Keyword(s):  
Stress Responses ◽  
Lipid Production ◽  
Nitrogen Deficiency ◽  
Carotenoid Content ◽  
Composition Analysis ◽  
Dependent Manner ◽  
Carotenoid Concentration ◽  
Carotenoid Production ◽  
Algal Strain ◽  
Scenedesmus Rubescens

The microalgal strain Scenedesmus rubescens KNUA042 was identified in freshwater in Korea and characterized by evaluating its stress responses in an effort to increase lipid and carotenoid production. Under a two-stage cultivation process, the algal strain that generally exhibits optimal growth at a nitrate (source of nitrogen) concentration of 0.25 g L−1 was challenged to different exogenous stimuli—salinity (S), light intensity (L), combined L and S (LS), and nitrogen deficiency (C)—for 14 days. Lipid production and carotenoid concentration increased in a time-dependent manner under these physicochemical conditions during the culture periods. Lipid accumulation was confirmed by thin layer chromatography, BODIPY staining, and fatty acid composition analysis, which showed no differences in the algal cells tested under all four (C, S, L, and LS) conditions. The quality of biodiesel produced from the biomass of the algal cells met the American Society for Testing and Materials and the European standards. Total carotenoid content was increased in the LS-treated algal cells (6.94 mg L−1) compared with that in the C-, S-, and L-treated algal cells 1.75, 4.15, and 1.32 mg L−1, respectively). Accordingly, the concentration of canthaxanthin and astaxanthin was also maximized in the LS-treated algal cells at 1.73 and 1.11 mg g−1, respectively, whereas lutein showed no differences in the cells analyzed. Conversely, chlorophyll a level was similar among the C-, S-, and LS-treated algal cells, except for the L-treated algal cells. Thus, our results suggested that S. rubescens KNUA042 was capable of producing carotenoid molecules, which led to the maximum values of canthaxanthin and astaxanthin concentrations when exposed to the combined LS condition compared with that observed when exposed to the salinity condition alone. This indicates that the algal strain could be used for the production of high-value products as well as biofuel. Furthermore, this article provides the first evidence of carotenoid production in S. rubescens KNUA042.

scholarly journals Strategies for Improvement of Lipid Production by Yeast Trichosporon oleaginosus from Lignocellulosic Biomass

2021 ◽  
Vol 7 (11) ◽  
pp. 934
Author(s):  
Marina Grubišić ◽  
Katarina Mihajlovski ◽  
Ana Marija Gruičić ◽  
Sunčica Beluhan ◽  
Božidar Santek ◽  
...  
Keyword(s):  
Lignocellulosic Biomass ◽  
Low Cost ◽  
Lipid Production ◽  
Tween 80 ◽  
Biodiesel Production ◽  
Hydrolysis Rate ◽  
Efficient Production ◽  
Fed Batch ◽  
Batch Mode ◽  
Lipid Yield

Microbial lipids have similar fatty acid composition to plant oils, and therefore, are considered as an alternative feedstock for biodiesel production. Oleaginous yeasts accumulate considerable amounts of lipids intracellularly during growth on low-cost renewable feedstocks such as lignocellulosic biomass. In this study, we cultivated yeast Trichosporon oleaginosus on hydrolysate of alkaline pretreated corn cobs. Different process configurations were evaluated and compared, including separate hydrolysis and fermentation (SHF) with cellulase recycle and simultaneous saccharification and fermentation (SSF) in batch and fed-batch mode. At low enzyme loading, the highest lipid concentration of 26.74 g L−1 was reached in fed-batch SSF fed with 2.5% (g g−1) substrate. Batch SHF was conducted for four rounds with recycling the cellulase adsorbed on unhydrolyzed lignocellulosic biomass. Thirty percent of cellulase saving was achieved for rounds 2–4 without compromising productivity and lipid yield. The addition of Tween 80 to lignocellulosic slurry improved the hydrolysis rate of structural carbohydrates in pretreated lignocellulosic biomass. Furthermore, supplementing the growth medium with Tween 80 improved lipid yield and productivity without affecting yeast growth. Oleaginous yeast T. oleaginosus is a promising strain for the sustainable and efficient production of lipids from renewable lignocellulosic feedstock.

scholarly journals Sugarcane Distillery Spent Wash, a New Resource for Third-Generation Biodiesel Production

Water ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1623 ◽  
Author(s):  
Julien Hoarau ◽  
Isabelle Grondin ◽  
Yanis Caro ◽  
Thomas Petit
Keyword(s):  
Low Cost ◽  
Lipid Production ◽  
Liquid Waste ◽  
Fungal Growth ◽  
Dry Weight ◽  
Biodiesel Production ◽  
Aspergillus Awamori ◽  
Cryptococcus Curvatus ◽  
Spent Wash ◽  
Distillery Spent Wash

Industrial production of biodiesel from microbial catalysts requires large volume of low-cost feedstock for lipid production. Vinasse, also known as distillery spent wash (DSW), is a liquid waste produced in large amounts by ethanol distilleries. This effluent is particularly rich in organic matter, and may be considered as a potential resource for the production of fungal lipids. The present study aimed at evaluating the potential of vinasse from a distillery located in Reunion Island for yeast and fungal growth, lipid production, and suitability for biodiesel requirements. Among the 28 different strains tested, we found that Aspergillus niger grown on pure vinasse allowed biomass production of up to 24.05 g/L (dry weight), whereas Aspergillus awamori produced the maximum amount of lipid, at 2.27 g/L. Nutrient removal and vinasse remediation were found to be the best for A. niger and Cryptococcus curvatus, reaching a maximum of 50% for nitrogen, and A. awamori showed 50% carbon removal. Lipids produced were principally composed of C16:0, C18:1 (n-9), and C18:2 (n-6), thus resembling the vegetal oil used in the biodiesel production. This work has shown that vinasse can support production of biomass and lipids from fungi and yeast suitable for energetic use and that its polluting charge can be significantly reduced through this process.

scholarly journals Microalgae as Sustainable Renewable Energy Feedstock for Biofuel Production

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Srikanth Reddy Medipally ◽  
Fatimah Md. Yusoff ◽  
Sanjoy Banerjee ◽  
M. Shariff
Keyword(s):  
Renewable Energy ◽  
Low Cost ◽  
Renewable Energy Sources ◽  
Lipid Production ◽  
Biomass Concentration ◽  
Commercial Production ◽  
Biodiesel Production ◽  
Biofuel Production ◽  
Energy Sources ◽  
Sustainable Renewable Energy

The world energy crisis and increased greenhouse gas emissions have driven the search for alternative and environmentally friendly renewable energy sources. According to life cycle analysis, microalgae biofuel is identified as one of the major renewable energy sources for sustainable development, with potential to replace the fossil-based fuels. Microalgae biofuel was devoid of the major drawbacks associated with oil crops and lignocelluloses-based biofuels. Algae-based biofuels are technically and economically viable and cost competitive, require no additional lands, require minimal water use, and mitigate atmospheric CO2. However, commercial production of microalgae biodiesel is still not feasible due to the low biomass concentration and costly downstream processes. The viability of microalgae biodiesel production can be achieved by designing advanced photobioreactors, developing low cost technologies for biomass harvesting, drying, and oil extraction. Commercial production can also be accomplished by improving the genetic engineering strategies to control environmental stress conditions and by engineering metabolic pathways for high lipid production. In addition, new emerging technologies such as algal-bacterial interactions for enhancement of microalgae growth and lipid production are also explored. This review focuses mainly on the problems encountered in the commercial production of microalgae biofuels and the possible techniques to overcome these difficulties.

scholarly journals Optimization media from low-cost nutrient sources for growing Spirulina platensis and carotenoid production Optimasi media dengan sumber nutrisi murah untuk pertumbuhan dan produksi karotenoid Spirulina platensis

2016 ◽  
Vol 69 (1) ◽  
Author(s):  
. TRI-PANJI ◽  
. SUHARYANTO
Keyword(s):  
Bioactive Compounds ◽  
Spirulina Platensis ◽  
Low Cost ◽  
Carotenoid Content ◽  
Media Composition ◽  
Organic Complex ◽  
Nutrient Sources ◽  
Carotenoid Production ◽  
Reference Medium ◽  
Tlc Analysis

SummarySpirulina platensis is a cyanobacteriaproducing several bioactive compounds such ascarotenoids which are economically valuable. Toproduce carotenoids in S. platensis biomassefficiently, it is necessary to define an optimummedium composition consisting of mineral saltand organic complex derived from low-costnutrient sources. Spirulina platensis grown oncomplex media containing latex serum fromconcentrated latex factory, supplemented withsalt minerals might produce high yieldingcarotenoids. The objective of this research is todefine media composition for optimum growthand carotenoid production of S. platensis and toidentify carotenoid compounds from biomass ofthe algae. S. platensis was grown on mediacontaining latex serum from latex concentratefactory (5%, v/v), macroelements andmicroelements, for 10 weeks at a room aeratedand illuminated by 20 W TL lamp at 50 cmdistance. Microelements were formulatedat a certain amount to give eleven combinationsof C: N: P: Mg. The Aiba & Ogawa syntheticmedium was used as a reference medium. Theoptimum growth of S. platensis had reachedafter eight-week incubation. Among elevenmedia composition containing latex serumexamined, best growth on a formulated mediumwith a ratio of C: N: P: Mg = 1:3:0.3:0.2 yielding0.350 g biomass/L This amount was slightlylesser than those on synthetic Aiba & Ogawamedium that yields 0.407 g biomass/L, aftereight-week incubation. Although the biomassproduction was lower than that of synthetic Aiba & Ogawa medium, the formulated mediagave higher carotenoid content. The highestcarotenoid content in biomass was 2.866 mg/kgbiomass obtained from a medium with ratio ofC: N: P: Mg = 1: 2: 0.3: 0. Thin layerchromatography (TLC) analysis of biomassextract showed the presence of two-six carotenoidcompounds, in which one of them is β- carotene.RingkasanSpirulina platensis adalah sianobakteria yangmenghasilkan berbagai senyawa bioaktif bernilaiekonomi tinggi antara lain karotenoida. Untukmemproduksi karotenoida dari biomassa selS. platensis secara efisien, perlu ditetapkankomposisi media mineral dan bahan organikkompleks yang optimal dari sumber nutrisi yangmurah. Spirulina platensis yang ditumbuhkandalam media serum lateks dari pabrik latekspekat dengan suplemen garam-garam mineraltertentu diharapkan produktif dalammenghasilkan karotenoida. Tujuan penelitianadalah menetapkan komposisi media yangoptimal untuk pertumbuhan dan produksikarotenoid serta mengidentifikasi jenis senyawakarotenoid dalam biomassa sel S. platensis.Sianobakteria ini ditumbuhkan dalam mediakompleks mengandung serum lateks pekat(5%, v/v) dengan suplemen nutrisi berupamakronutrien dan mikronutrien selama10 minggu di dalam ruangan dengan aerasi danpenyinaran lampu TL 20 W pada jarak 50 cm.Komposisi makronutrien diformulasi untukmemberikan sebelas macam variasi nisbahC:N:P:Mg. Sebagai pembanding digunakanmedia sintetik Aiba & Ogawa. Hasil penelitianmenunjukkan bahwa pertumbuhan S. platensismencapai puncak setelah diinkubasikan selamadelapan minggu. Dari 11 komposisi mediamengandung lateks yang diuji, pertumbuhanS. platensis terbaik adalah yang ditumbuhkandalam media formula dengan nisbah C:N:P:Mg=1:3:0.3:0.2 menghasilkan 0,350 g biomassa/L,sedikit lebih rendah dibandingkan denganmenggunakan media sintetik Aiba & Ogawa yangmenghasilkan 0,407 g biomassa/L selama8 minggu. Walaupun kandungan biomassanyalebih rendah, media formula tersebut meng-hasilkan karotenoid lebih tinggi dibandingkandengan media sintetik Aiba & Ogawa.Kandungan karotenoid tertinggi pada biomassayaitu sebesar 2.866 mg/kg diperoleh pada mediadengan nisbah C:N:P:Mg=1:2:0.3:0. Analisisekstrak biomassa dengan TLC menunjukkanadanya dua-enam jenis karotenoida, salahsatunya adalah β - karotena.

scholarly journals An Overview of Biodiesel Production via Calcium Oxide Based Catalysts: Current State and Perspective

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3950
Author(s):  
Hoora Mazaheri ◽  
Hwai Chyuan Ong ◽  
Zeynab Amini ◽  
Haji Hassan Masjuki ◽  
M. Mofijur ◽  
...  
Keyword(s):  
Heterogeneous Catalysis ◽  
Calcium Oxide ◽  
Heterogeneous Catalysts ◽  
Low Cost ◽  
Biodiesel Production ◽  
Catalyst Synthesis ◽  
Process Improvements ◽  
Current State ◽  
The Common ◽  
Activity Mechanism

Biodiesel is a clean, renewable, liquid fuel that can be used in existing diesel engines without modification as pure or blend. Transesterification (the primary process for biodiesel generation) via heterogeneous catalysis using low-cost waste feedstocks for catalyst synthesis improves the economics of biodiesel production. Heterogeneous catalysts are preferred for the industrial generation of biodiesel due to their robustness and low costs due to the easy separation and relatively higher reusability. Calcium oxides found in abundance in nature, e.g., in seashells and eggshells, are promising candidates for the synthesis of heterogeneous catalysts. However, process improvements are required to design productive calcium oxide-based catalysts at an industrial scale. The current work presents an overview of the biodiesel production advancements using calcium oxide-based catalysts (e.g., pure, supported, and mixed with metal oxides). The review discusses different factors involved in the synthesis of calcium oxide-based catalysts, and the effect of reaction parameters on the biodiesel yield of calcium oxide-based catalysis are studied. Further, the common reactor designs used for the heterogeneous catalysis using calcium oxide-based catalysts are explained. Moreover, the catalytic activity mechanism, challenges and prospects of the application of calcium oxide-based catalysts in biodiesel generation are discussed. The study of calcium oxide-based catalyst should continue to be evaluated for the potential of their application in the commercial sector as they remain the pivotal goal of these studies.

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