Volume 13, No. 2 (2012)
Articles
NEW COMPLEX SELENITO AND OXALATO ADDUCTS CONTAINING SnPh3 AND SnPh2 RESIDUES: SYNTHESIS AND SPECTROSCOPIC STUDIES
SEYDI MANSOUR SECK(1), WALY DIALLO(1), LIBASSE DIOP(1*), LORENZO STIEVANO(2)
Three new organotin complexes (two selenito and an oxalate one) adducts have been synthesized and studied by infrared and Mössbauer techniques. A discrete structure is suggested with a bi-unidentate selenito oxyanion and trans bipyramidal SnPh3 residue; the oxalato adduct can be seen as an insertion compound between C2O4(SnPh3)2 and [Cu(En)3]C2O4•4SnPh2C2O4. This last compound has a discrete ionic structure with cis coordinated SnPh2 residues.
NEW ORGANOTIN (IV) OXALATO ADDUCTS: SYNTHESIS AND SPECTROSCOPIC STUDIES
SEYDI MANSOUR SY SECK(1), LIBASSE DIOP(1*), LORENZO STIEVANO(2)
Seven new oxalato organotin (IV) adducts have been synthesized, their infrared and Mössbauer studies carried out. Their structures are discrete, the oxalate behaving as a chelating or bridging ligand. The key role of the cation is noteworthy.
WHEAT FLOUR HUMIDITY VARIATION WITH UV-VIS RADIATION DOSE REVEALED BY SPECTRAL AND CHEMOMETRIC STUDIES
IULIANA MIHAELA LAZĂR(1,2), ALINA MIHAELA MOROI(1), IRINA LOREDANA IFRIM(1*), NICOLETA VARTOLOMEI(1), ALISA-VASILICA ARUŞ(1)
The cells’ exposure to UV radiation induces mutations of the cellular components by its action on DNA, protein synthesis and enzymatic activities. Different varieties of wheat flour were treated with UV-B, UV-A, Vis radiation and compared with untreated samples. The IR spectra for these components were recorded with a Bruker FTIR spectrophotometer using an ATR method, at 4 cm-1 resolution. The paper proposes a comparative study of unmaturing flour behavior under UV-Vis and natural radiations in order to observe the physico-chemical changing by FTIR spectroscopy. At small doses of irradiation (up to 2 h) the humidity of the samples decreases and then it significantly increases, most pronounced in Gruia’s case where the humidity is reaching 74.4% of the initial value. Middle infrared spectral studies reveal an inverse weak linear correlation between Amide I region (1650 cm-1) (R-squared value: -0.3168) and an inverse medium linear correlation assigned to area alcohol O-H band at 3290 cm-1 (R-squared value: -0.6064) with the irradiation dose variables. Strong direct linear correlations confirmed by R-squared value: 0.7835 are found between alcohol O-H band at 3290 cm-1 and humidity percentage parameter.
SYNTHESIS OF ACRYLIC ESTERS IN PHASE TRANSFER CATALYSIS: KINETICS AND ECOLOGICAL ASPECTS
GAGIK TOROSYAN(1), GHAZI AIDAN(2), NVER TOROSYAN(3)
Phase-Transfer Catalysis (PTC) technology is used in the commercial manufacture and also in pollution mitigation treatment processes. In the paper is demonstrated the synthesis of esters of acrylic and metacrylic acids, which have wide applications in the industry for the synthesis of unique polymeric materials, by phase transfer catalysis method. It is necessary to notice that the synthesis of acrylic acids in PTC medium is more important because that compounds are more sensitive at acidic and basic conditions. Here is shown that the offered method has more advantages in comparison with the traditional methods. PTC is characterized by a higher degree of conversion of raw materials into useful products, smaller material and power resources consumption. The offered method for acrylic ester synthesis in comparison with the traditional methods has more advantages: higher process rates, mild reaction conditions, allowing lower energy costs, the complete elimination of hazardous and dangerous organic solvents, all leading to a sharp reduction of air pollution, and volume of generated wastewaters.
RHEOLOGICAL PROPERTIES OF RAPESEED OIL AND HYDRAULIC OIL
IOANA STANCIU(*)
This article presents the rheological behavior of refined rapeseed oil and hydraulic oil. Apparent viscosity of both oils was determined at temperatures between 40 and 90°C and shear rates ranging from 3.3 to 120 s-1. The aim of the study was to find a polynomial dependence of oil viscosity on temperature and shear rate. The modified Andrade equation was used. Constants A, B, C and correlation coefficient were determined by correlating a characteristic polynomial equation of each curve.
FACTORS INFLUENCING THE SOLUBILIZATION CAPACITY OF WATER/OIL MICROEMULSIONS<br/>FACTEURS INFLUENÇANT LA CAPACITÉ DE SOLUBILISATION DES MICROÉMULSIONS EAU/HUILE
SANDU PERETZ(1*), CRISTINA STOIAN(2), GHEORGHE ZGHEREA(2)
The solubilization capacity of water / oil / AOT (sodium bis(2 ethylhexyl)sulfosuccinate) microemulsions was studied as a function of a fourth component added in the system. Addition of cosurfactant modifies the water solubility and the properties of the system. The influence of some alcohols with linear and branched hydrocarbon chains and a cationic hydrosoluble dye, methylene blue (MB), on the solubilization of water in water/oil microemulsions was studied. The value of the molar ratio of water to surfactant, R, increases in the alcohols presence as the volume of solubilized water was increased. The increasing of R leads also to a significant increase of the radius of water-core of the droplets in microemulsion. A separation of water in w/o microemulsion appears when concentration of alcohol is 9×10-4 M and the volume of water increases, becoming 1.2 to 2.5 times higher if the concentration of alcohol rises to 1.2×10-3 M. Addition of MB into microemulsion leads to the doubling of the volume of separated water. The partition of MB between microemulsion and water phases shows that the dye migrates preferentially in the microemulsion phase in the presence of alcohols.
EFFECT OF BAKING ON THE PHYSICAL-CHEMICAL CHARACTERISTICS AND THE HYGIENICAL QUALITY OF BISCUITS<br/>EFFET DE LA CUISSON SUR LES CARACTERISTIQUES PHYSICO-CHIMIQUES ET LA QUALITE SANITAIRE DES BISCUITS
MOHAMED MAMOUMI(1,2), HANANE FIKRI(1), RACHID SLIMANI(2), HAMID AMAROUCHE(1), MOULAY MUSTAPHA ENNAJI(3), MOHAMED ZAHOUILY(1*), SAÏD LAZAR(2*)
The food safety is necessary of development of agro-food industries. We opted for the introduction of a concept to ensure a sanitary control of products-wares, including the pastry. We chose for our project three parameters as: water activity (aw), pH and moisture. Also, we defined the target values for these parameters to ensure the safety of our pastry. Otherwise, we incorporated the factor temperature to ensure complete control of safety knowing that cooking is a major industry in the pastry. We defined the temperature of microbial destruction to reduce the microbial load of the pastry after baking. This study was approved by microbiological analysis carried out on the cake having undergone the following parameters (aw, pH, moisture, temperature of microbial destruction).
PRESERVING QUALITY OF FROZEN GREEN PEAS DURING LONG TIME STORAGE<br/>PRÉSERVER LA QUALITÉ DES PETITS POIS VERTS SURGELÉS PENDANT L'ENTREPOSAGE
FELICIA DIMA(*), CAMELIA VIZIREANU, DANIELA ISTRATI
The purpose of this study was to analyze the degree which fresh green peas maintain their technological properties and nutritional components during long-term storage, for a period of 24 months, in a defined condition of the air, at maximum -18°C. Peas were blanched, at four different durations of this operation and the same temperature of the blanching water, 95°C. The peas were frozen after end stored. In conditions of long-term storage of frozen peas, it has been found a considerable loss of the initial content of vitamin C and damage of chlorophyll (total, a and b), under the action of chlorophyllase, causing some gray compounds. The conditions of the storage in frozen stage produced a distortion of color and sensorial qualities, higher as the storage temperature was higher than prescribed. It was found that the best results in preserving quality of peas during long-term storage (24 months) were obtained for the blanched samples at 4 minutes at 95°C. The reducing of the content of vitamin C, chlorophyll a and b, and sensorial qualities was the lowest, overall.
STUDY OF GUSTATORY AND STRUCTURAL PROPERTIES OF KEFIR PRODUCT
MILENA H. MOMCHILOVA(1*), GERGANA B. IVANOVA(1), AKSENIYA ATANASOVA(2), NEVENKA RUMYAN(2), NELLY V. GEORGIEVA(1)
The subject of the study is the improvement of Kefir culture. For this investigation it was used Kefir culture and two series of experiments were carried out. Yeasts from probiotic strain Saccharomyces boulardii were added in the first series and the lactic acid bacteria (LAB) of Streptococcus thermophilus strain, with a polysaccharide activity were added to Kefir culture in the second series. The fermentation conditions were 30°C, duration 16 hours and cooling 4 hours up to 4°C. The characteristics of Kefir were analyzed by determination of: pH, acidity, qualitative reaction for existence of diacetyl, cell number of LAB and yeasts. The structural properties of Kefir were evaluated by microscopic study.
THE INFLUENCE OF CULTURE MEDIA ON ACETIC FERMENTATION WITH SELECTED Acetobacter STRAINS
MARIA CRISTIANA GARNAI
We have systematically followed the efficiency of acetic fermentation, by cultivating 14 Acetobacter strains (previously isolated and identified), within a medium obtain out of ethanol and acetic acid, in various proportions, and utilizing corn extract (CE) as a nutrient. The purpose of the research was to determine the resistance of the studied Acetobacter strains related to the composition of the cultivation media (acidity and alcohol content of the medium), as well as following the dynamics of the acetic fermentation by calculating the practical yield. The research led to optimal variants which may be industrially exploited in order to obtain vinegar.
PRELIMINARY STUDY REGARDING THE USE OF SOME Yarrowia lipolytica STRAINS FOR SOLID STATE HYDROLYSIS OF CRUDE COCONUT FAT
GEORGIANA PARFENE(*), VICENTIU BOGDAN HORINCAR, GABRIELA BAHRIM
Coconut fat could be an important source of bioactive compounds with a large applicability in industry. In this study it was realized the enzymatic hydrolysis of coconut fat with different yeast strains of Yarrowia lipolytica. The aim of this study was to optimize the hydrolysis conditions and determination of Yarrowia lipolytica specificity on coconut fat as substrate. The hydrolysis was performed by yeast strains cultivated on stationary solid state conditions on spirit blue agar medium supplemented with 3% coconut fat, at 25°C and 4°C, and at values of water activity of 0.98, 0.96 and 0.93. The substrate hydrolysis index was recorded every 24 hours, during of 240 hours of stationary cultivation. The most active lipolytic yeast was strain coded S5 which produce a high level of extracellular lipase with high coconut hydrolyze activity at 25°C and two water activities 0.98 and 0.96, in the shortest time (24 – 72 hours). In the presence of 3% NaCl in media, the strains coded S9, S5 and S4 were the most active from all tested strains at 25°C and 4°C. At low temperatures and in presence of 10.1% NaCl all tested yeasts had no lipolytic activity.
THE USE OF PSEUDO-CEREALS FLOURS IN BAKERY<br/> UTILISATION DE FARINES DES PSEUDO-CEREALES DANS LA BOULANGERIE
ROMULUS MARIAN BURLUC(*), CAMELIA VIZIREANU, RODICA DINICA, FELICIA DIMA
Nowadays, a special attention should be given to the nutritional properties of foods. In the bakery industry there is a tendency to develop innovative range of bakery products by using the therapeutic role of cereals that are not used at their true potential (buckwheat, millet, rice, oats). Among bioactive components present in the pseudocereal flours, flavones group is highlighted, in particular rutine, the most important ramnoglicosid with multiple beneficial effects on health. The aims of this study were the obtention of different bakery products (bread, biscuits) from raw materials with high therapeutic potential (fiber, antioxidant capacity, minerals), the optimization of process parameters and recipes, and the characterization of finished products in terms of sensory and physico-chemical properties. The results confirm that the use of unusual raw materials for the Romanian market led to obtaining high quality finished products with special therapeutic features.
BIOHUMUS PRODUCTION BY WORMS’ COMPOSTING OF SOME FOOD WASTES
DANIELA SUTEU(1*), CARMEN ZAHARIA(2), MARINELA BADEANU(3)
A laboratory set-up scale application of a simple worms’ composting technology is presented together with the waste and biohumus characterization, description of technological process and operational conditions. The laboratory application is not a complicated one, when the optimum conditions necessary for the digestion process are accomplished and is recommended in the farms where the biodegradable wastes are produced and accumulated in moderate quantities. The main product, biohumus, can be used as fertilizer for the soil, in agriculture or flower cropping.
REVIEW OF WASTEWATER FROM THE CITY OF OUAGADOUGOU: SELF-PURIFICATION CAPACITY FOR THE PRODUCTION OF BIOGAS<br/> BILAN DES EAUX USEES DE LA VILLE DE OUAGADOUGOU : CAPACITE AUTO-EPURATOIRE EN VUE DE LA PRODUCTION DE BIOGAZ
INOUSSA ZONGO(1,2*), MARTINE DIALLO-KONÉ(1), KALIFA PALM(1), ABLASSE TIEMTORE(1), OUMAR SANOGO(1), EDOUARD GUIGUEMDE(1), FRANÇOIS LAPICQUE(3), JEAN-PIERRE LECLERC(3)
The two tests realized in this study show that the anaerobic conditions are better than the aerobic ones in order to treat most of the effluents of Ouagadougou in Burkina Faso. This essay allows 95% reduction of greenhouse gases specifically CO2 by anaerobic way. The survey of effluent gives 14456000 m3•yr-1 with 3.716 mg O2•L-1 COD and 790520 m3 yr-1 of industrial wastewater with 2238 mg O2•L-1. The potential of biogas based on the domestic wastewater is evaluated to 30.256 m3 per day.
KINETIC AND THERMODYNAMIC STUDY OF THE ADSORPTION OF MANGANESE (II) ON ACTIVATED CARBON
OUISSAF BENTABET(1), HASSINA BOUGHERARA(1), LAURENCE REINERT(2), LAURENT DUCLAUX(2), BRAHIM KEBABI(1*)
Recent studies revealed the Bay of Algiers was being polluted by manganese. Similar pollution was also reported in Azemmour, Morocco alongside the estuary of Oum Er Rbia, but also in the waters of developed countries (i.e. Canada, especially following the replacement of tetraethylplumbane in gasoline by methylcyclopentadienyl manganese). Treatment of polluted waters by manganese is therefore essential prior to their release, which is within the purpose of the present study. Commercial activated carbon (AC) was used for treating synthetic aqueous solution containing different concentrations of Mn. Adsorption kinetics was studied under agitation at different temperatures between 295 and 318 K. Results show that there are two areas where adsorption occurs according to a first-class model. In the first one, rate constant is k1 = 0.001610 min-1, meanwhile in the second, it is k2 = 0.000488 min-1. Equilibrium is reached in 7 hours. The obtained adsorption isotherm is a V type and follows Freundlich model for low concentrations and Langmuir model for high concentrations. The isotherm part described by Freundlich model lessens with the rise of temperature, increasing adsorption maximum capacity from 3.49 mg Mn/g AC (at 295 K) to 4.78 mg Mn/g AC (at 318 K). Adsorption is endothermic. Standard enthalpy (14.4869 kJ•mol-1) and standard entropy (36.25 J•mol-1•K-1) have been calculated. The free energy was positive in all the studied temperatures range. The values of adsorption heat indicate a physical adsorption.
EUGENOL POLYMER MODIFIED TITANIUM ELECTRODE FOR THE ANALYSIS OF CARBOCYSTEINE
S. EL QOUATLI, R.T. NGONO, R. NAJIH, A. CHTAINI(*)
A eugenol polymer immobilized electrode was developed for the assay of the carbocysteine compound. The electrochemical sensor was made by in situ electropolymerization of eugenol at titanium electrode. Cyclic voltamperometry at prepared electrode permitted to point out a reversible pattern for carbocysteine electrooxidation.
PHYTOCHEMICAL STUDY OF A TINCTORIAL PLANT OF BENIN TRADITIONAL PHARMACOPOEIA: THE RED SORGHUM (Sorghum caudatum) OF BENIN
PASCAL D.C. AGBANGNAN(1,2,3), CHRISTINE TACHON(2), HELENE BONIN(2), ANNA CHROSTOWKA(2), ERIC FOUQUET(3), DOMINIQUE C.K. SOHOUNHLOUE(1*)
The full phytochemical screening of red sorghum from Benin (Sorghum caudatum) achieved in this work reveals the presence of leucoanthocyanins, flavonoides, free quinones, combined anthracene derivatives, sterols and terpenes in higher concentration in the leaf sheath and marrow of stem than in the seed. Catechin tannin content is 11.4% in the leaf sheath (slightly higher than that of red wine), 5.8% in the marrow and 2.8% in the seed. Gallic tannins, saponins and the mucilage present in the leaf sheath and marrow, are virtually absent in the seed. Marrow and leaf sheath extracts (1 g/50 mL) showed a concentration of anthocyanins (147 mg/L and 213.5 mg/L) similar to that of rosy wine and red wine with short maceration. The grain of sorghum is four times, respectively two times less rich in phenolic compounds than the leaf sheath and the marrow of stem.