Alina Violeta Ursu

SIGMA Clermont · Chemical Engineering

Ursu A.V, Djelveh. G, Gros F, Jinescu G

In this work the extraction of EPSs from culture media of P. cruentum, by dialysis, solvent-precipitation with 3 polar alcohols (methanol, ethanol and isopropanol) and membrane separation techniques has been studied. Diafiltration (DF) using a membrane with a 300 kDa molecular weight cut off was the most efficient technique compared to solvent-extr...

Organoclays with improved affinity towards carbon dioxide were obtained via montmorillonite intercalation with polyol and amino dendrimers having respectively hydroxyl or amino groups that act as adsorbing sites. Measurements through thermal programmed desorption (TPD) show that higher amounts of CO2 than predicted by stoichiometry were retained by...

Alginic acids and alginates have important applications in food, medicine, pharmaceutical industry, dentistry and textile. The sodium alginate from Nizimuddinia zanardini (an Iranian brown seaweed) was extracted with high voltage electrical discharge to investigate the influence of this extraction method on its structural and physico-chemical chara...

Bioactive compounds with diverse chemical structures play a significant role in disease prevention and maintenance of physiological functions. Due to the increase in industrial demand for new biosourced molecules, several types of biomasses are being exploited for the identification of bioactive metabolites and techno-functional biomolecules that a...

Marine seaweeds represent a natural resource for which the scientific and the industrial communities have shown an ever-increasing interest in the past few years. Historically, their exploitation was largely linked to the industrial demand for hydrocolloids such as carrageenan, agar and alginate which gave to marine seaweed a significant economical...

Solutions of Asafoetida gum (2 % w/w) were used to prepare oil in water emulsion with various oil/gum solution ratios (0.5, 1.0, 2.0, 3.0 and 4.0 v/v). Stability and rheological properties of the emulsions were examined over 28 days of storage at 20 °C. It was revealed that increasing oil volume fraction enhanced the emulsion stability. The results...

The asafoetida gum was extracted and purified from oleo-gum-resin of Ferula assa foetida root and characterized by high pressure anions exchange chromatography after acidic hydrolysis. It was composed of Gal:Ara:Rha:GlcA with the ratio 11.5:5.0:2.1:1.0. This monosaccharide composition was found similar to that of a commercial Arabic gum which exhib...

A fucoidan (CCF) and a sodium alginate (CCSA) were extracted and purified from the Tunisian brown seaweed Cystoseira compressa. CCF was a highly sulfated heterogalactofucan composed of α-(1→3), α-(1→4)-linked l-Fucp as main backbone which could be highly branched (31.84%) at O-3 and O-4 positions of α-(1→4)-l-Fucp and α-(1→3)-l-Fucp by terminal mon...

Sodium alginate from Nizimuddinia zanardini (an Iranian brown algae) was extracted with acid and alkaline solutions, partially and totally hydrolyzed and analyzed for its biochemical composition. 1H NMR spectroscopy, SEC-MALLS, HPAEC and FT-IR were performed to determine its structure and its physico-chemical properties. This alginate has a M/G rat...

Background: Regarded as biofunctional poly- and oligomers having much higher potential than cellulose in many fields, chitosan and its derivatives have become of great interest thanks to the recent progress in chitin chemistry. Chitosan, which is a natural-based polymer obtained by alkaline deacetylation of chitin, is an interesting bioactive polys...

The gum asafoetida, an oleo-gum-resin from root of Ferula assa foetida, was extracted through alcoholic procedure followed by water extraction and then biochemically characterized using colorimetric assays, Fourier infrared spectroscopy, gas chromatography coupled to mass spectrometry, and 1D and 2D nuclear magnetic resonance. The gum was mainly co...

Polysaccharides de plantes de milieux arides, Université de Ouargla

Ethanol insoluble materials were separated and oven dried at 80 °C The supernatant was mixed with three volumes of ethanol letting to precipitate overnight at 4 °C. The resulting powder was mixed with five fold (w/w) of distilled water, stirred for 30 min at 45 °C. Compositional analysis: total sugar (phenol sulfuric method), total uronic acid) m-h...

The production of cooked ham on an industrial scale generates two liquid by-products: pork exudate (PE), collected before the salting, has 14% weight dry matter, mainly rich in proteins (90%); ham broth (HB), released after cooking, has 8% dry matter including 50% proteins. The biochemical, rheological and functional properties of these by-products...

Les effluents liquides générés par l’industrie salaisonnière avant et après l’étape de cuisson sont riches en protéines (de 50 à 95% de la matière sèche). Nous avons montré que la matrice protéique contenue dans ces jus présente une large distribution de masses moléculaires (entre 1 et ~250 kDa). Au-delà de leur valeur nutritionnelle cette large di...

Les spirulines sont des microorganismes photosynthétiques (cyanobactéries) qualifiées de microalgues car elles se développent rapidement par photosynthèse dans un milieu aqueux. Elles sont particulièrement intéressantes par leur richesse en protéines (entre 45 et 70 % de la matière sèche selon l’espèce et les conditions de culture) dont une partie...

Ham industry has to manage two types of by-products during ham processing. Fresh pork juice is produced during the storage of meat by dripping before ham preparation. This by-product contains 90% proteins based on dry mass (14%). Ham preparation includes steps of brining, mixing and steam cooking. During this last operation, non negligible amount o...

The production of ham at industrial scale generates high amounts of liquid effluents that can reach up to 10% of the final ham tonnage. These effluents containing proteins and salts are poorly valorised and represent a non negligible cost in terms of treatment. The aim of this work is to suggest a way to include these by-products as nutritional and...

Ce travail concerne une étude comparative entre les variables dynamiques en fluidisation sous le champ magnétique coaxial (FSCMC) dans deux types de configurations: mélange pseudo-homogène et multicouches. Le mélange est constitué de particules d'argile modifiée par pontage avec des cations d'aluminium et de billes d’acier pour une utilisation dans...

Chaque année, l’industrie salaisonnière génère une quantité non négligeable de jus avant (jus exsudé de la viande de porc) ou après l’opération de cuisson du jambon. Or, ces jus contiennent des fractions de protéiques intéressantes : environ 13% pour le jus frais et 4% de protéines pour 6 à 7% de matière sèche pour le jus de cuisson contenant égale...

Microalgae are good resources for bioenergy production because of their fast growing ability, their sustainability and their high lipids content without competition with arable lands. However such raw material also contains a relatively high amount of potential functional and/or bioactive molecules such as polysaccharides, pigments and proteins tha...

This study aims to investigate the dynamic parameters of pseudo homogenous mixtures of aluminum pillared clay and ferromagnetic steel particles (APC-FMS) in classic fluidization and in fluidization stabilized in coaxial magnetic field. For both dynamic conditions of fluidization the structure of the bed was important in order to enhance a quasi hom...

The microalgal structure has been investigated to evaluate the release of proteins in aqueous media from five microalgae after conducting different cell disruption techniques: manual grinding, ultrasonication, alkaline treatment, and high-pressure treatment. After conducting cell disruption, the protein concentration in water was determined for all...

Ce travail a donc pour objet le développement d’un procédé d’extraction et de séparation des protéines issues de la microalgue C. vulgaris. La caractérisation des fractions protéiques en termes de propriétés physico-chimiques (répartition des masses moléculaires et point isoélectrique) est menée au moyen de techniques de protéomique et de chromatog...

Chlorella vulgaris is a well-known fresh water microalgae largely exploited in nutraceutics for its high protein content. However, no literature described the use of protein extracts of this strain for their functional properties. In this work extraction, solubilisation and functional properties of Chlorella vulgaris were investigated. Melted bioma...

L’utilisation des microalgues pour la production d’énergie fait l’objet de plus en plus de recherches scientifiques. Cependant si les microalgues contiennent une fraction importante de lipides, en fonction des conditions de culture, elles contiennent également des quantités non négligeables de protéines et de polysaccharides valorisables. C’est dan...

The extraction and fractionation of main components of microalgae such as Porphyridium cruentum and Chlorella vulgaris, known as a source of interesting biomolecules, remain an open question. The aim of this work is to set-up the experimental procedure to extract, isolate, fractionate and quantify polysaccharides and proteins from these two microal...

This paper presents a study on modeling and optimization of lactic fermentation process in the presence of anionic clays using experiments design. It is used a 33 type experiment design (three parameters and three levels of variation). Variable parameters of the process were: pasteurization temperature of milk, solidliquid ratio, fermentation durat...

The paper presents the results of experimental research for the preparation of anionic clays, hydrotalcite-type compounds with different molar ratios Mg:Al, by the co-precipitation method at low saturation, using as raw materials the nitrates as precursors of Mg and Al cations. The obtained clays were characterized from different points of view (ch...

La stabilisation magnétique consiste à appliquer un champ magnétique permanent d’orientation donnée (transverse ou colinéaire à l’écoulement) sur un milieu poreux aimantable [1]. Elle a pour conséquence la combinaison des avantages de la fluidisation et de la filtration : une faible perte de charge (lit fluidisé) et l’élimination des bulles (lit fi...

Ion-exchanged montmorillonite-rich materials (ca. 96% purity) like NaMt, Fe(II)Mt, Co(II)Mt, Ni(II)Mt and Cu(II)Mt showed catalytic activity in the ozonation of oxalic acid in water at room temperature, in the pH range 3.4–6.0. The conversion of oxalic acid exceeds 95% after 180 min of ozone bubbling in the presence of Fe(II)Mt. The oxalic acid rem...

Microporous organo-montmorillonites (organo-Mt) bearing weak base OH sites were prepared through montmorillonite intercalation with polyol dendrimers at different proportions (0.5, 1.0 and 3.0mass%). These materials turned out to be suitable for the reversible capture of carbon dioxide, inasmuch as high amount (0.5–2.5mmol/g organo-Mt) of CO2 can b...

The paper studies the hydrodynamic of the gas/solid fluidization in a transverse magnetic field of ferromagnetic particles (commercial steel). The influence of solid (magnetic and non-magnetic particles) characteristics, and the magnetic field intensity (in the range of 0-12000 A.m-1), on the pressure drop and porosity of the granulated bed has bee...

This paper presents experimental data regarding the hydrodynamic of the gas/solid fluidization in a transverse magnetic field of a binary mixture of clay (smectitic acid activated clays) – magnetic particles and of clay particles in classical fluidized bed. The influence of solid (magnetic and non-magnetic particles) characteristics, magnetic field...

Experimental research of dynamic structure of the granular beds of clay, steel and clay- metallic particles mixtures aimed to determine the operating fluidization parameters, to identify optimal conditions for contacting gas - granular material and to intensify mass transfer operations with minimum energy consumption. The main dynamic parameters of...

Ca–bentonite originating from a Romanian deposit was leached in 0.5–8.0 M HCl solution at 90 �C for 4 h. This material was fully characterized through BET, thermogravimetry, X-rays diffraction, and elemental analysis. The acid treatment at high temperature altered the crystallinity, but produced an increase in the surface area and thermal stability...

The aim of this paper is to study the use of a mixture of commercial clay namely K10 and a natural Romanian sodium bentonite in the adsorption of NH3 contained in air using fixed and fluidized bed gas-solid reactors. Qualitative (DRX) and quantitative (XPS, DTG) analysis were performed. Clays were agglomerated and treated with NH3. Adsorption isoth...

The invention relates to a process for obtaining a catalyst for water purification from organic compounds and may be used in the sterilization and degasification of aqueous solutions for food industry. The process includes utilization of the montmorillonite-type clay, purification thereof from quartz and cristobalite by repeated sedimentation into...

The invention relates to the water treatment, in particular to a process for coagulationflocculation and may be used during metal cation removal from water. The process provides for the utilization of a mineral component on base of a montmorillonite-type clay purified by quartz, cristobalite and organic impurities, in one of the native states or mo...

Metal cations were removed from water by coagulation–flocculation of the chitosan–montmorillonite system. Co2+, Ni2+ and Cu2+ were used as probe cations. It was found that both chitosan and montmorillonite contribute to the metal ion removal, when used separately, and that coagulation–flocculation strongly depends on the pH and composition of the l...

Distribution of the acid–base strengths of various ion-exchanged montmorillonites was assessed through thermal programmed desorption (TPD) of NH3 and CO2. Accurate acid–base measurements can be achieved via deconvolution of perfectly symmetrical peaks, under optimal carrier gas throughput and heating rate, estimated though a factorial experiment de...