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1. Fermentable Sugar Production from a Coffee Processing By-product after Deep Eutectic Solvent Pretreatment

Author:
Rehmann, Lars,   et al.   ; Procentese, Alessandra;     Show all 2 Author
Source:
Bioresource technology reports 2018 v.4 pp. 174-180
ISSN:
2589-014X
Subject:
X-ray diffraction; beverage industry; biomass; byproducts; choline; glucose; glycerol; lignocellulose; scanning electron microscopy; solvents; temperature
Abstract:
... Deep eutectic solvents (DES) can be a promising medium for lignocellulose biomass processing. The present paper investigates suitable operating conditions for the DES pretreatment on coffee silverskin (CS), a waste stream from the coffee industry. Choline chloride/glycerol was used as a low-cost DES, and the solid to solvent ratio and temperature were varied during processing. An optimal set of op ...
DOI:
10.1016/j.biteb.2018.10.012

2. High throughput screening of β-glucuronidase (GUS) reporter in transgenic microalgae transformed by Agrobacterium tumefaciens

Author:
Rehmann, Lars,   et al.   ; Yedahalli, Shreyas; Bassi, Amarjeet;     Show all 3 Authors
Source:
Algal research 2018 v.33 pp. 328-336
ISSN:
2211-9264
Subject:
Agrobacterium radiobacter; Chlorella vulgaris; Escherichia coli; beta-glucuronidase; chemiluminescence; cost effectiveness; enzyme activity; fluorescence; gene fusion; genetically modified organisms; labor; mammals; microalgae; octoxynol; reporter genes; screening; yeasts
Abstract:
... GUS (β-glucuronidase) is a chemiluminescent reporter gene that has been used in E. coli, fungi, yeast, mammalian cells, plant cells and microalgae. Currently, the GUS gene fusion system used for detection of GUS enzyme activity is carried out by cell lysis and requires 500 μl cell lysate. Hence, GUS activity cannot be assessed by high throughput screening (HTS) method. This study addresses this by ...
DOI:
10.1016/j.algal.2018.06.007

3. Assessment of water samples with complex compositions using microalgal bioassay based on the community level physiological profiling (CLPP)

Author:
Rehmann, Lars,   et al.   ; Kim, Jun-Woo; Ray, Madhumita B.;     Show all 3 Authors
Source:
Journal of environmental management 2018 v.224 pp. 310-314
ISSN:
0301-4797
Subject:
activated carbon; bioassays; microalgae; oil sands; principal component analysis; surface water; temporal variation; wastewater; water quality; wetlands; yeasts; Ontario
Abstract:
... The ability to effectively characterize the response of microalgal communities to changes in water quality is limited. Earlier, a microalgal bioassay was developed based on community level physiological profiling (CLPP). The efficacy of this assay was evaluated using three wetland water samples, a surface water sample, and two wastewater samples (i.e. primary and secondary), all collected from sou ...
DOI:
10.1016/j.jenvman.2018.07.055

4. The role of 1,3-propanediol production in fermentation of glycerol by Clostridium pasteurianum

Author:
Rehmann, Lars,   et al.   ; Johnson, Erin E.;     Show all 2 Author
Source:
Bioresource technology 2016 v.209 pp. 1-7
ISSN:
0960-8524
Subject:
Clostridium pasteurianum; biodiesel; butanol; carbon dioxide production; cell growth; continuous fermentation; ethanol; fuel production; glycerol; homeostasis; pH
Abstract:
... Waste crude glycerol from biodiesel production can be used to produce biobutanol using Clostridium pasteurianum with the main products being n-butanol, 1,3-propanediol (PDO) and ethanol. There has been much discrepancy and mystery around the cause and effect of process parameters on the product distribution, thus a better understanding of the pathway regulation is required. This study shows that a ...
DOI:
10.1016/j.biortech.2016.02.088

5. Deep Eutectic Solvents pretreatment of agro-industrial food waste

Author:
Rehmann, Lars,   et al.   ; Procentese, Alessandra; Raganati, Francesca; Olivieri, Giuseppe; Russo, Maria Elena; Marzocchella, Antonio;     Show all 6 Authors
Source:
Biotechnology for biofuels 2018 v.11 no.1 pp. 37
ISSN:
1754-6834
Subject:
apples; biodegradability; biomass; choline; enzymes; food waste; fuels; hydrolysis; industry; ionic liquids; lignocellulose; market analysis; potatoes; spent grains; sugars; temperature; Europe
Abstract:
... BACKGROUND: Waste biomass from agro-food industries are a reliable and readily exploitable resource. From the circular economy point of view, direct residues from these industries exploited for production of fuel/chemicals is a winning issue, because it reduces the environmental/cost impact and improves the eco-sustainability of productions. RESULTS: The present paper reports recent results of dee ...
DOI:
10.1186/s13068-018-1034-y
PubMed:
29449885
PubMed Central:
PMC5808427

6. Improvement of the Nile Red fluorescence assay for determination of total lipid content in microalgae independent of chlorophyll content

Author:
Rehmann, Lars,   et al.   ; Orr, Valerie;     Show all 2 Author
Source:
Journal of applied phycology 2015 v.27 no.6 pp. 2181-2189
ISSN:
0921-8971
Subject:
screening; lipid content; sampling; detection limit; absorption; fluorescence; emissions factor; solvents; biofuels; red light; triolein; microalgae; chlorophyll
Abstract:
... Rapid determination of the specific lipid content of microalgae can accelerate screening and development of algae fuel application. Until recently, lipid content was commonly measured using gravimetric solvent extraction. Such methodology is time consuming and requires relatively large sample volumes. The Nile Red lipid assay has recently gained acceptance as it requires minute sample sizes. Howev ...
DOI:
10.1007/s10811-014-0481-5

7. Optimizing Acid Hydrolysis of Jerusalem Artichoke-Derived Inulin for Fermentative Butanol Production

Author:
Rehmann, Lars,   et al.   ; Sarchami, Tahereh;     Show all 2 Author
Source:
BioEnergy research 2015 v.8 no.3 pp. 1148-1157
ISSN:
1939-1234
Subject:
temperature; fermentation; sugars; Clostridium; sulfuric acid; response surface methodology; crop yield; hydrochloric acid; pH; phosphoric acid; butanol; acid hydrolysis; feedstocks; inulin; hydrolysates; Jerusalem artichokes; hydroxymethylfurfural
Abstract:
... In this study, a central composite design and response surface methodology were used to study the effect of various hydrolysis variables (temperature, pH, and time) on the acid hydrolysis of Jerusalem artichoke-derived inulin using three different mineral acids (HCl, H₂SO₄, and H₃PO₄). Numerical optimization was used to maximize the sugar yield of Jerusalem artichoke powder within the experimental ...
DOI:
10.1007/s12155-014-9568-8

8. Development of microalgal bioassay based on the community level physiological profiling (CLPP)

Author:
Rehmann, Lars,   et al.   ; Kim, Jun-Woo; Ray, Madhumita B.;     Show all 3 Authors
Source:
Algal research 2017 v.25 pp. 47-53
ISSN:
2211-9264
Subject:
Chlamydomonas reinhardtii; Chlorella vulgaris; Scenedesmus obliquus; Selenastrum capricornutum; ammonium chloride; bioassays; freshwater; microalgae; penicillins; pollutants; principal component analysis; sodium; streptomycin; sulfates
Abstract:
... Microalgal bioassay was developed based on community level physiological profiling (CLPP) to assess the effect of environmental stressors such as micropollutants. ECO Biolog plates were used to determine the changes in substrate utilization patterns caused by external disturbances such as the presence of antibiotics (a mixture of streptomycin sulfate and penicillin GT sodium), hexadecyl trimethyl ...
DOI:
10.1016/j.algal.2017.04.037

9. Direct Conversion of the Oleaginous Yeast Rhodosporidium diobovatum to Biodiesel Using the Ionic Liquid [C2mim][EtSO4]

Author:
Rehmann, Lars,   et al.   ; Ward, Valerie C. A.; Munch, Garret; Cicek, Nazim;     Show all 4 Authors
Source:
ACS sustainable chemistry 2017 v.5 no.6 pp. 5562-5570
ISSN:
2168-0485
Subject:
Rhodosporidium; biodiesel; biomass; catalysts; fatty acid methyl esters; ionic liquids; methanol; potassium hydroxide; response surface methodology; screening; temperature; transesterification; yeasts
Abstract:
... In this study, the direct conversion of wet oleaginous yeast biomass to fatty acid methyl esters (FAME) using base transesterification in the presence of an ionic liquid was optimized. The ionic liquid, 1-ethyl-3-methylimidazolium ethylsulfate, was used to facilitate this process and improved the yields of FAME transesterified directly from wet biomass using potassium hydroxide (KOH) as a catalyst ...
DOI:
10.1021/acssuschemeng.7b00976

10. Optimization of fermentation condition favoring butanol production from glycerol by Clostridium pasteurianum DSM 525

Author:
Rehmann, Lars,   et al.   ; Sarchami, Tahereh; Johnson, Erin;     Show all 3 Authors
Source:
Bioresource technology 2016 v.208 pp. 73-80
ISSN:
0960-8524
Subject:
Clostridium pasteurianum; analysis of variance; biodiesel; bioreactors; butanol; feedstocks; fermentation; fuel production; glycerol; inoculum; models; pH; temperature
Abstract:
... Butanol is a promising biofuel and valuable platform chemical that can be produced through fermentative conversion of glycerol. The initial fermentation conditions for butanol production from pure glycerol by Clostridium pasteurianum DSM 525 were optimized via a central composite design. The effect of inoculum age, initial cell density, initial pH of medium and temperature were quantified and a qu ...
DOI:
10.1016/j.biortech.2016.02.062

11. Xylose removal from lignocellulosic biomass via a twin-screw extruder: The effects of screw configurations and operating conditions

Author:
Rehmann, Lars,   et al.   ; Zheng, Jun; Choo, Kim;     Show all 3 Authors
Source:
Biomass and bioenergy 2016 v.88 pp. 10-16
ISSN:
0961-9534
Subject:
agitation; biomass; corn cobs; energy; lignocellulose; temperature; water flow; xylose
Abstract:
... It was the objective of this study to evaluate the feasibility of separating xylose from lignocellulosic biomass (steam-exploded corncobs) in a co-rotating twin-screw extruder, through water addition and solid–liquid separation. Eight screw configuration profiles were evaluated to define the best performance on xylose recovery. Subsequently, operating conditions (barrel temperature, screw speed an ...
DOI:
10.1016/j.biombioe.2016.03.012

12. Butanol fermentation from microalgae-derived carbohydrates after ionic liquid extraction

Author:
Rehmann, Lars,   et al.   ; Gao, Kai; Orr, Valerie;     Show all 3 Authors
Source:
Bioresource technology 2016 v.206 pp. 77-85
ISSN:
0960-8524
Subject:
acetone; acid hydrolysis; alcohol fuels; algae; biodiesel; butanol; ethanol; feedstocks; fermentation; fuel production; hexane; hydrolysates; ionic liquids; lignocellulose; lipids; starch
Abstract:
... Lipid extracted algae (LEA) is an attractive feedstock for alcohol fuel production as it is a non-food crop which is largely composed of readily fermented carbohydrates like starch rather than the more recalcitrant lignocellulosic materials currently under intense development. This study compares the suitability of ionic liquid extracted algae (ILEA) and hexane extracted algae (HEA) for acetone, b ...
DOI:
10.1016/j.biortech.2016.01.036

13. Optimizing enzymatic hydrolysis of inulin from Jerusalem artichoke tubers for fermentative butanol production

Author:
Rehmann, Lars,   et al.   ; Sarchami, Tahereh;     Show all 2 Author
Source:
Biomass and bioenergy 2014 v.69 pp. 175-182
ISSN:
0961-9534
Subject:
Clostridium; Jerusalem artichokes; analysis of variance; butanol; enzymatic hydrolysis; feedstocks; fermentation; hydrolysates; inulin; models; pH; response surface methodology; temperature; tubers
Abstract:
... In this study, a central composite design and response surface methodology were used to study the effect of various enzymatic hydrolysis variables (temperature, pH, substrate concentration and enzyme loading) on the enzymatic hydrolysis of Jerusalem artichoke-derived inulin. It was found that a quadratic model was able to predict inulin conversion as a function of all four investigated factors. Th ...
DOI:
10.1016/j.biombioe.2014.07.018

14. ABE fermentation from enzymatic hydrolysate of NaOH-pretreated corncobs

Author:
Rehmann, Lars,   et al.   ; Gao, Kai;     Show all 2 Author
Source:
Biomass and bioenergy 2014 v.66 pp. 110-115
ISSN:
0961-9534
Subject:
Clostridium; acetone; butanol; corn cobs; enzymatic hydrolysis; ethanol; fermentation; hydrolysates; reducing sugars; sediments; sodium hydroxide; solvents
Abstract:
... Acetone butanol ethanol (ABE) was produced from enzymatic-hydrolyzed corncobs by Clostridium saccharobutylicum DSM 13864. Pretreatment of corncobs was carried out with 0.5 mol L−1 NaOH followed by enzymatic hydrolysis. The yield of total reducing sugars was 917 g kg−1 pretreated (de-lignified) and washed corncobs. The hydrolysate was used without sediments removal for ABE fermentation. A solvent p ...
DOI:
10.1016/j.biombioe.2014.03.002

15. Low-energy biomass pretreatment with deep eutectic solvents for bio-butanol production

Author:
Rehmann, Lars,   et al.   ; Procentese, Alessandra; Raganati, Francesca; Olivieri, Giuseppe; Russo, Maria Elena; Marzocchella, Antonio;     Show all 6 Authors
Source:
Bioresource technology 2017 v.243 pp. 464-473
ISSN:
0960-8524
Subject:
Clostridium acetobutylicum; biomass; butanol; chlorides; choline; energy efficiency; fresh-cut produce; glucose; glycerol; hydrolysates; industry; lignocellulose; solvents; temperature; wastes; xylose
Abstract:
... Waste lettuce leaves – from the “fresh cut vegetable” industry – were pretreated with the deep eutectic solvent (DES) made of choline chloride – glycerol. Reaction time (3–16h) and the operation temperature (80–150°C) were investigated. Enzymatic glucose and xylose yields of 94.9% and 75.0%, respectively were obtained when the biomass was pretreated at 150°C for 16h. Sugars contained in the biomas ...
DOI:
10.1016/j.biortech.2017.06.143

16. Pervaporative butanol removal from PBE fermentation broths for the bioconversion of glycerol by Clostridium pasteurianum

Author:
Rehmann, Lars,   et al.   ; Kießlich, Sascha; Sarchami, Tahereh; Munch, Garret; Gao, Kai; Kujawski, Wojciech; Johnson, Erin;     Show all 7 Authors
Source:
Journal of membrane science 2017 v.535 pp. 79-88
ISSN:
0376-7388
Subject:
Clostridium pasteurianum; acetic acid; artificial membranes; biotransformation; butanol; culture media; feedstocks; fermentation; fermented foods; glycerol; models; pervaporation; polydimethylsiloxane; temperature; turbulent flow
Abstract:
... Batch-wise butanol removal using vacuum pervaporation (VPV) was investigated to assess its technical feasibility for future integration with a continuous PBE (1,3-propanediol-butanol-ethanol) fermentation process using glycerol as feedstock. Two commercial polydimethylsiloxane (PDMS) membrane configurations were characterized using binary model solutions and authentic fermentation broths, while va ...
DOI:
10.1016/j.memsci.2017.04.012

17. Consolidating biofuel platforms through the fermentative bioconversion of crude glycerol to butanol

Author:
Rehmann, Lars,   et al.   ; Johnson, Erin; Sarchami, Tahereh; Kießlich, Sascha; Munch, Garret;     Show all 5 Authors
Source:
World journal of microbiology & biotechnology 2016 v.32 no.6 pp. 103
ISSN:
0959-3993
Subject:
acylglycerols; animal fats and oils; biodiesel; biotransformation; butanol; byproducts; carbon; catalysts; diesel fuel; energy; feedstocks; free fatty acids; fuel production; gasoline; glycerol; infrastructure; markets; prices; vegetable oil
Abstract:
... Economic realities for the rising industrial biofuel production have changed substantially during the low oil price period starting in the mid 2010’s. Increased competition requires the sector to increase productivity through the reduction of low-value by-products and full utilization of all value and energy stored in their respective feedstock. Biodiesel is produced commercially from substrates s ...
DOI:
10.1007/s11274-016-2056-x

18. Pretreatment of Eastern White Pine (Pinus strobes L.) for Enzymatic Hydrolysis and Ethanol Production by Organic Electrolyte Solutions

Author:
Rehmann, Lars,   et al.   ; Tian, Xiaofei; Xu, Chunbao Charles; Fang, Zhen;     Show all 4 Authors
Source:
ACS sustainable chemistry 2016 v.4 no.5 pp. 2822-2829
ISSN:
2168-0485
Subject:
Pinus strobus; ambient temperature; biomass; cellulose; crystal structure; electrolytes; enzymatic hydrolysis; ethanol; ethanol fermentation; ethanol production; glucose; hemicellulose; hydrolysis; ionic liquids; lignin; wood
Abstract:
... Organic electrolyte solution (OES), composed of room temperature ionic liquids (RTILs) and polar organic solvent, was applied during the pretreatment of eastern white pine (EWP), one of the most recalcitrant woody biomass. The influence of various crucial parameters that govern the dissolution and further pretreatment process were examined. A gradual reduction of the crystallinity of cellulose I, ...
DOI:
10.1021/acssuschemeng.6b00328

19. The effects of screw elements on enzymatic digestibility of corncobs after pretreatment in a twin-screw extruder

Author:
Rehmann, Lars,   et al.   ; Zheng, Jun; Choo, Kim;     Show all 3 Authors
Source:
Biomass and bioenergy 2015 v.74 pp. 224-232
ISSN:
0961-9534
Subject:
biomass; cellulose; cellulosic fibers; corn cobs; digestibility; enzymatic hydrolysis; ethanol production; extrusion; kneading; lignin; lignocellulose; saccharification; scanning electron microscopy; sodium hydroxide
Abstract:
... Extrusion of lignocellulosic biomasses can be an effective physical continuous pretreatment method towards bioethanol production. Extrusion processes would typically precede enzymatic cellulose saccharification in a given pretreatment. The screw configuration determines the functionality of the extruder and different screw elements (conveying, kneading and reverse) can have different effects on en ...
DOI:
10.1016/j.biombioe.2015.01.022

20. Geometric Effects on Non-DLVO Forces: Relevance for Nanosystems

Author:
Rehmann, Lars,   et al.   ; Wood, Jeffery A.;     Show all 2 Author
Source:
Langmuir 2014 v.30 no.16 pp. 4623-4632
ISSN:
1520-5827
Subject:
atomic force microscopy; bacterial adhesion; equations; geometry; nanoparticles
Abstract:
... In this paper, the surface element integration (SEI) method was used derive analytical force/potential versus distance profiles for two non-DLVO forces: Lewis acid–base and solvation forces. These forces are highly relevant in a variety of systems, from bacterial adhesion, nanoparticle suspension stability to atomic force microscopy (AFM) profiles. The SEI-derived expressions were compared with th ...
DOI:
10.1021/la500664c