37 Bd Of Luniversite

Saint-Nazaire, France

37 Bd Of Luniversite

Saint-Nazaire, France

Time filter

Source Type

Parniakov O.,CNRS Integrated Transformations of Renewable Matter | Parniakov O.,Ukrainian Academy of Sciences | Barba F.J.,University of Valencia | Grimi N.,CNRS Integrated Transformations of Renewable Matter | And 5 more authors.
Innovative Food Science and Emerging Technologies | Year: 2015

This work studies the potential of the pulsed electric field (PEF) assisted extraction of nutritionally valuable compounds from microalgae Nannochloropsis spp. using the binary mixture of organic solvents (dimethyl sulfoxide, DMSO and ethanol, EtOH) and water. The one-stage (EI) and two stage (EII) extraction procedures were compared. The procedure EI included the common extraction using the binary mixtures. Two stage (EII) extraction procedure involved PEF-treatment (20 kV/cm) of microalgae suspension (1% wt.) and extraction in water as the first step. The second step included the common extraction using the binary mixtures. The effects of extraction procedure and concentration of organic solvents in water on extraction of total chlorophylls, carotenoids, proteins, phenolic compounds and value of antioxidant capacity, TEAC, were analyzed. The proposed two stage PEF-assisted procedure allowed also effective extraction in less concentrated mixtures of organic solvents with water. Industrial relevance Pre-treatment by pulsed electric field PEF) allowed highly selective extraction of different nutrients from microalgae biomass. The combination of PEF and solvent extraction in the binary mixture of organic solvents (dimethyl sulfoxide, DMSO and ethanol (EtOH)) and water allowed reaching of the high level of extraction pigments and non-degraded proteins. The obtained data can be useful for optimization of the concentration organic solvents in industrial extraction processes. © 2014 Elsevier Ltd. All rights reserved.


Parniakov O.,CNRS Integrated Transformations of Renewable Matter | Parniakov O.,Ukrainian Academy of Sciences | Barba F.J.,University of Valencia | Grimi N.,CNRS Integrated Transformations of Renewable Matter | And 5 more authors.
Algal Research | Year: 2015

The study was aimed at investigation of the potential of pulsed electric field (PEF) pre-treatment as a preliminary step of pH-assisted aqueous extraction of algae components from microalgae Nannochloropsis suspensions. The PEF and sonication (S) were compared as pretreatment methods. They were applied at normal (pH. =. 8.5) and basic (pH. =. 11) conditions, and supplementary basic extraction (at pH. =. 11) was done. The extracts were analyzed for content of pigments, proteins, carbohydrates, total phenolic compounds and antioxidant capacity. The colloidal stability of PEF- and S-pretreated suspensions was also evaluated. The data evidence that PEF technique allows selective extraction of a portion of pure proteins that are different from proteins extracted from S-pretreated suspensions. The discovered effects have shown the advantages of PEF-pretreatment at normal conditions (pH. =. 8.5) and supplementary extraction at basic conditions (pH. =. 11) for selective extraction of different intracellular components. © 2015 Elsevier B.V.


Caporgno M.P.,Rovira i Virgili University | Olkiewicz M.,Rovira i Virgili University | Pruvost J.,University of Nantes | Lepine O.,37 Bd Of Luniversite | And 3 more authors.
Bioresource Technology | Year: 2016

The aim of this work was to study the effect of the solvent N-methylmorpholine-N-oxide (NMMO) to pre-treat Nannochloropsis oculata before the anaerobic digestion process. The results indicated that the pre-treatment affects the characteristics of the cell wall, which consequently becomes more susceptible to the microorganisms attack during anaerobic digestion. The methane production was increased by 43% after the pre-treatment, from 238±6mLCH4/gVS until 339±4mLCH4/gVS. On the contrary, the methane production from Chlorella vulgaris decreased after the pre-treatment from 251±4mLCH4/gVS to 231±3mLCH4/gVS. The failure on the pre-treatment was attributed to the particular characteristics of the substrate in consequence of a previous drying step. © 2015 Elsevier Ltd.


Caporgno M.P.,Rovira i Virgili University | Pruvost J.,University of Nantes | Legrand J.,University of Nantes | Lepine O.,37 Bd Of Luniversite | And 2 more authors.
Bioresource Technology | Year: 2016

Although the hydrothermal liquefaction is considered a promising technology for converting microalgae into liquid biofuels, there are still some disadvantages. This paper demonstrated that the bio-oil yield can be significantly improved by adding alcohols as co-solvents and carrying out the conversion at mild conditions (<250 °C), but at the expense of a reduced bio-oil quality. By adding ethanol, the bio-oil yields obtained (up to ∼60%) were comparable to the yield obtained at severe operating conditions using only water as solvent (54 ± 2% on average), but the quality of the bio-oil was lower. However, the main advantages of the process here described lie in the utilisation of wet microalgae (∼75% moisture) and alcohol concentrations which avoid both drying the microalgae and decreasing the amount of microalgae loaded in the reactor. © 2016 Elsevier Ltd.


Grimi N.,CNRS Integrated Transformations of Renewable Matter | Dubois A.,CNRS Integrated Transformations of Renewable Matter | Dubois A.,University of Nantes | Marchal L.,University of Nantes | And 4 more authors.
Bioresource Technology | Year: 2014

This work studies the extraction of intracellular components from microalgae Nannochloropsis sp. with application of different cell disruption techniques, including pulsed electric field (PEF) (20. kV/cm, 1-4. ms, 13.3-53.1. kJ/kg), high voltage electrical discharge (HVED) (40. kV/cm, 1-4. ms, 13.3-53.1. kJ/kg), ultrasonication (USN) (200. W, 1-8. min, 12-96. kJ/kg), and high pressure homogenization (HPH) (150. MPa, 1-10 passes, 150-1500. kJ/kg). The data evidence that electrically based disruption techniques (PEF and HVED) allowed selective extraction of water soluble ionic components and microelements, small molecular weight organic compounds and water soluble proteins. Microscopic and sedimentation stability analyses have shown that microalgae cells in HVED-treated suspension were noticeably agglomerated and could be easily settled in centrifuge. The electrically based disruption techniques were ineffective for delivery of pigments (e.g., chlorophylls or carotenoids) and their extraction required subsequent application of more potent disruption techniques. The obtained data have shown that HPH disruption technique was the most effective; however, this mode required the highest power consumption. © 2013 Elsevier Ltd.


Olkiewicz M.,Rovira i Virgili University | Caporgno M.P.,Rovira i Virgili University | Font J.,Rovira i Virgili University | Legrand J.,University of Nantes | And 5 more authors.
Green Chemistry | Year: 2015

The use of a hydrated phosphonium ionic liquid, [P(CH2OH)4]Cl, for the extraction of microalgæ lipids for biodiesel production, was evaluated using two microalgæ species, Chlorella vulgaris and Nannochloropsis oculata. The ionic liquid extraction was compared to the conventional Soxhlet, and Bligh & Dyer, methods, giving the highest extraction efficiency in the case of C. vulgaris, at 8.1%. The extraction from N. oculata achieved the highest lipid yield for Bligh & Dyer (17.3%), while the ionic liquid extracted 12.8%. Nevertheless, the ionic liquid extraction showed high affinity to neutral/saponifiable lipids, resulting in the highest fatty acid methyl esters (FAMEs)-biodiesel yield (4.5%) for C. vulgaris. For N. oculata, the FAMEs yield of the ionic liquid and Bligh & Dyer extraction methods were similar (>8%), and much higher than for Soxhlet (<5%). The ionic liquid extraction proved especially suitable for lipid extraction from wet biomass, giving even higher extraction yields than from dry biomass, 14.9% and 12.8%, respectively (N. oculata). Remarkably, the overall yield of FAMEs was almost unchanged, 8.1% and 8.0%, for dry and wet biomass. The ionic liquid extraction process was also studied at ambient temperature, varying the extraction time, giving 75% of lipid and 93% of FAMEs recovery after thirty minutes, as compared to the extraction at 100 °C for one day. The recyclability study demonstrated that the ionic liquid was unchanged after treatment, and was successfully reused. The ionic liquid used is best described as [P(CH2OH)4]Cl·2H2O, where the water is not free, but strongly bound to the ions. © The Royal Society of Chemistry 2015.


PubMed | University of Nantes, 37 Bd Of Luniversite and University of Southern Brittany
Type: | Journal: Bioresource technology | Year: 2015

A study of cell disruption by bead milling for two microalgae, Nannochloropsis oculata and Porphyridium cruentum, was performed. Strains robustness was quantified by high-pressure disruption assays. The hydrodynamics in the bead mill grinding chamber was studied by Residence Time Distribution modeling. Operating parameters effects were analyzed and modeled in terms of stress intensities and stress number. RTD corresponded to a 2 CSTR in series model. First order kinetics cell disruption was modeled in consequence. Continuous bead milling was efficient for both strains disruption. SI-SN modeling was successfully adapted to microalgae. As predicted by high pressure assays, N. oculata was more resistant than P. cruentum. The critical stress intensity was twice more important for N. oculata than for P. cruentum. SI-SN modeling allows the determination of operating parameters minimizing energy consumption and gives a scalable approach to develop and optimize microalgal disruption by bead milling.


PubMed | University of Nantes, 37 Bd Of Luniversite and CNRS Integrated Transformations of Renewable Matter
Type: | Journal: Bioresource technology | Year: 2014

This work studies the extraction of intracellular components from microalgae Nannochloropsis sp. with application of different cell disruption techniques, including pulsed electric field (PEF) (20kV/cm, 1-4ms, 13.3-53.1kJ/kg), high voltage electrical discharge (HVED) (40kV/cm, 1-4ms, 13.3-53.1kJ/kg), ultrasonication (USN) (200W, 1-8min, 12-96kJ/kg), and high pressure homogenization (HPH) (150MPa, 1-10 passes, 150-1500kJ/kg). The data evidence that electrically based disruption techniques (PEF and HVED) allowed selective extraction of water soluble ionic components and microelements, small molecular weight organic compounds and water soluble proteins. Microscopic and sedimentation stability analyses have shown that microalgae cells in HVED-treated suspension were noticeably agglomerated and could be easily settled in centrifuge. The electrically based disruption techniques were ineffective for delivery of pigments (e.g., chlorophylls or carotenoids) and their extraction required subsequent application of more potent disruption techniques. The obtained data have shown that HPH disruption technique was the most effective; however, this mode required the highest power consumption.


PubMed | University of Nantes, Rovira i Virgili University and 37 Bd Of Luniversite
Type: | Journal: Bioresource technology | Year: 2015

The aim of this work was to study the effect of the solvent N-methylmorpholine-N-oxide (NMMO) to pre-treat Nannochloropsis oculata before the anaerobic digestion process. The results indicated that the pre-treatment affects the characteristics of the cell wall, which consequently becomes more susceptible to the microorganisms attack during anaerobic digestion. The methane production was increased by 43% after the pre-treatment, from 2386mLCH4/gVS until 3394mLCH4/gVS. On the contrary, the methane production from Chlorella vulgaris decreased after the pre-treatment from 2514mLCH4/gVS to 2313mLCH4/gVS. The failure on the pre-treatment was attributed to the particular characteristics of the substrate in consequence of a previous drying step.


PubMed | University of Nantes, Rovira i Virgili University, 37 Bd Of Luniversite and Ecole des Mines de Nantes
Type: | Journal: Bioresource technology | Year: 2016

Although the hydrothermal liquefaction is considered a promising technology for converting microalgae into liquid biofuels, there are still some disadvantages. This paper demonstrated that the bio-oil yield can be significantly improved by adding alcohols as co-solvents and carrying out the conversion at mild conditions (<250C), but at the expense of a reduced bio-oil quality. By adding ethanol, the bio-oil yields obtained (up to 60%) were comparable to the yield obtained at severe operating conditions using only water as solvent (542% on average), but the quality of the bio-oil was lower. However, the main advantages of the process here described lie in the utilisation of wet microalgae (75% moisture) and alcohol concentrations which avoid both drying the microalgae and decreasing the amount of microalgae loaded in the reactor.

Loading 37 Bd Of Luniversite collaborators
Loading 37 Bd Of Luniversite collaborators