Volume 16, No. 1 (2015)
Articles
COMPARATIVE PERFORMANCE OF SAND AND COCONUT SUBSTRATE IN URBAN WASTEWATER TREATMENT </br> PERFORMANCES COMPAREES DU SABLE ET DU SUBSTRAT DE COCO EN TRAITEMENT D’EAUX RESIDUAIRES URBAINES
MARTINE KONE(1*), GILLES COMTES(2), MADJELIA SOME(1), INOUSSA ZONGO(1), PIERRE JOLY(2)
Urban wastewater has been treated by infiltration-percolation on sand and on coconut substrate, in order to highlight their comparative performance. The pilots were fed to the hydraulic loading rate of 40 L·m-2·d-1 during three days a week and kept at rest the next four days. Parameters are measured on an average sample of 24 hours taken on the output of each pilot at the end of the third day of treatment. The average removal efficiencies of chemical oxygen demand (COD) were respectively, 94.8 and 39.61 % with the sand and the coconut substrate while the average yields of biochemical oxygen demand (BOD5) were 99.01 and 98.12 %. The results showed that the average removal efficiencies of fecal coliform bacteria were respectively, 98.8 and 91 %. Conductivities have increased by an average of 39.88 % with the sand and 4.65 % with coconut substrate.
STUDY OF THE PREPARATION OF SUGAR FROM HIGH-LIGNIN LIGNOCELLULOSE APPLYING SUBCRITICAL WATER AND ENZYMATIC HYDROLYSIS: SYNTHESIS AND CONSUMABLE COST EVALUATION
HANNY F. SANGIAN, DIAN RANGGINA, GALIH M. GINTING, AGENG A. PURBA, SETIYO GUNAWAN, ARIEF WIDJAJA(*)
This study concern sugars hydrolyzed from the high-lignin coconut coir dust using moderate subcritical water (SCW) hydrolysis at pressures 20-40 bar for 1 h and to evaluate the consumable costs driver generated. The SCW method produced two products, sugar liquid and solid (SCW-treated substrate). The solid was proceeded to prepare the sugar via enzymatic hydrolysis using pure cellulase. Yield of sugar hydrolyzed from lignocellulose by SCW technique was 0.25 gram sugar/gram cellulose +hemicellulose, or 0.09-gram sugar/gram lignocellulose at 160 °C and 40 bar. While, the maximum yield of sugar liberated enzymatically from SCW-treated solid was 0.35-gram sugar/gram cellulose+hemicellulose, or 0.13-gram sugar/gram SCW-treated solid. It was found that carbon dioxide gas was the highest cost driving in SCW hydrolysis.
A COMPARATIVE STUDY ON ANTIOXIDANT ACTIVITIES AND PHENOLIC CONTENTS OF FIVE ALGERIAN EGGPLANT CULTIVARS
CHÉRIFA BOUBEKRI, TOUHAMI LANEZ(*), ASSIA DJOUADI
Total phenolic content and antioxidant activity were measured in the whole fruit of dark-purple eggplant cultivars from five different regions of east Algeria using, respectively, the Folin-Ciocalteu method, spectrophotometrical and electrochemical assays. Total phenolic contents were highest in sample from Jijel, followed by Skikda cultivars, finally sample from Guelma with the lowest phenolic contents. Total phenolic content was positively associated with total antioxidant activity in eggplant extracts. These results demonstrate that phenolic compounds have a significant contribution to the total antioxidant activity, which varies considerably depending on the region of the fruit cultivar analyzed. Antioxidant activity was highly correlated with total phenolic contents (R2 = 0.714).
TOXICOLOGICAL DRUG SCREENING BY GC-MS VERSUS HPLC-DAD USING A COMMON EFFICIENT EXTRACTION PROCEDURE </br> SCREENING TOXICOLOGIQUE DES MEDICAMENTS PAR HPLC-DAD ET GC-MS: PROTOCOLE D’EXTRACTION UNIQUE
SELOUA ELMRABEH(1*), MOHAMMED IBRIZ(1), MOHAMMED GHANDI(2), NAIMA AITDAOUD(1, 2), MOUNA BENTAFRIT(2), NARJIS BADRANE(2), ABDELMAJID SOULAYMANI(1), RACHIDA SOULAYMANI BENCHEIKH(2)
This paper presents a common extraction method for toxicological drug screening by gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography with diode-array detection (HPLC-DAD). Liquid-liquid extraction was performed using plasma of 104 samples at the Laboratory of Moroccan Poison Control and Pharmacovigilance Center during a period of 12 months. The results obtained by HPLC-DAD are compared with those determined with GC-MS. 76 cases (73.08 %) were found positive for at least by one of these two techniques. HPLC-DAD identified 59.87 % of all positive results, and 10 molecules were identified only by HPLC-DAD. GC/MS identified 40.13 % of all positives, and 4 molecules were identified only by GC/MS. In order to evaluate the performance of this extraction method, an extraction yield was calculated for three classes of drugs. All the analyzed molecules were obtained in satisfactory yields (higher than 50 %) except for carbamazepine, amitriptyline and nortriptyline. Overall, the results indicate that the extraction method is well adapted for toxicological drug screening. The use of common extraction simultaneously for the two techniques can reduce workload and costs of screening, while increasing the validity and reliability of the results.
C2O4(SnPh3)2 ISOMERS AND SOME OF THEIR ADDUCTS: SYNTHESIS AND SPECTROSCOPIC CHARACTERIZATION
YAYA SOW(1), CHEIKH ABDOUL KHADIR DIOP(1), LIBASSE DIOP(1*), BERNARD MAHIEU(2), LORENZO STIEVANO(3)
The study of the interactions between C2O4(SnPh3)2 and a Lewis base (Ph3PO) or salts such as Ph4PCl, (Bu2NH2)2C2O4.3H2O, (Pr2NH2)2C2O4(Cy2NH2)2C2O4.2H2O have yielded seven new adducts, infrared and Mossbauer studies which have been carried out. The suggested structures are discrete or of infinite chain type. Most of the structures contain C2O4(SnPh3)2 with cis coordinated SnPh3 residues characterized for the first time in this work. In Ph3PO containing adducts the Lewis base coordinates a SnPh3 residue. The oxalate behaves as a mo- or bidentate, a mono- or bichelating, a only hydrogen bonds involved ligand. In the structures of the compounds containing a non symmetrical cation, this one is involved in N-H…O hydrogen bonds.
NEW [SnR2(C2O4)2]2- (R = Ph, Bu) MOIETY CONTAINING ADDUCTS AND COMPLEXES: SYNTHESIS, INFRARED AND MOSSBAUER STUDIES
YAYA SOW, LIBASSE DIOP(*)
New oxalato and hydrogenoxalato organotin (IV) derivatives containing mono- and bichelating oxalates or a monochelating hydrogenoxalate, have been synthesized and characterized by elemental analyses, infrared and Mossbauer spectroscopy. The suggested structures are discrete, the environments around the tin (IV) atoms being trans octahedral, seven coordinated or tetrahedral. The cations when present are involved in NH…O bonds. A 1 D supramolecular architecture is suggested for SnPh2 (HC2O4)2.1/2 C6H6. The C6H6 molecules obtained in situ molecules are lattice. SnPh3OH is involved in hydrogen bonding.
ENHANCING THE EFFICIENCY OF AZO-BASED DYE SENSITIZED SOLAR CELLS BY SURFACE TREATMENTS
JEANINA LUNGU(1), ADRIAN GEORGESCU(1), ANCA DUMBRAVA(2*)
We studied the conductive glass and/or the semiconductor surface treatments with aluminum ions as a technique to enhance the characteristics of dye sensitized solar cells (DSSCs) based on Al-doped ZnO. The aluminum ions were deposited on the surfaces using aluminum isopropoxide as precursor, by an easy and efficient method. We measured the characteristics of the dye sensitized solar cells based on pre- and/or post-treated electrodes. Our study showed a clear enhancement of cells efficiencies for the DSSCs based on Al(III) pre-treated electrodes (i.e. a percentage increase of almost 18 %) and also a smaller improvement in the efficiencies of DSSCs based on Al(III) post-treated photoelectrodes (i.e. a percentage increase of almost 10 %), giving a overall enhance of about 21 % reported to the untreated photoelectrode based DSSC.
EFFECTS OF HORMONES ADDITION FOR IN VITRO PLANT DEVELOPMENT OF CALENDULLA OFFICINALIS
IRINA-CLAUDIA ALEXA(1), PETRONEL PAVĂL(1), DANIELA NICUŢĂ(2), PETRONELA BRAN(2), OANA-IRINA PATRICIU(1), LUMINIŢA GROSU(1), ADRIANA LUMINITA FINARU(1*)
The current study presented in vitro plant development of Calendula officinalis on MS (Murashige and Skoog) medium supplemented with different formula of hormones. The morphogenetic response was evaluated by recording the number of plantlets, the plant height and weight. The results showed that small amounts of hormones can improve the plantlets growth in the case of Calendula officinalis.
SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF A Zn(II) COORDINATION POLYMER BASED ON 4,4’-BIPYRIDINE AND ACETATO
LI-HUA WANG(*)
A novel Zn(II) coordination polymer, [Zn(bpy)(acetato)2]n (bpy = 4,4’-bipyridine), has been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. The Zn(II) coordination polymer is triclinic, space group P-1 with a = 8.046(3) Å, b = 9.161(3) Å, c = 10.663(3) Å, α = 109.769(4)º, β = 99.966(5)º, γ = 101.666(5)º, V= 699.1(4) Å3, Z = 2, Dc = 1.614 mg·m-3, μ = 1.774 mm-1, F(000) = 348, and final R1 = 0.0541, ωR2 = 0.1605. X-ray diffraction analysis reveals that the Zn(II) center is six-coordination with a N2O4 distorted octahedral coordination environment. The Zn(II) complex forms 1D chain structure by the bridge of 4,4’-bipyridine and acetato.
SYNTHESIS AND CRYSTAL STRUCTURE OF A Mg(II) COMPLEX WITH 2,6-PYRIDINEDICARBOXYLIC ACID
XI-SHI TAI(1*), GUANG-LI WANG(2), YUAN-YUAN LIU(1)
A Mg(II) complex, [MgL·(H2O)3]·2H2O (H2L = 2,6-pyridinedicarboxylic acid), has been synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction analysis. The Mg(II) complex belongs to monoclinic, space group P21/n with a = 8.9318(18) Å, b = 10.002(2) Å, c = 13.290(3) Å, β = 96.86(3)º, V= 1178.8(4) Å3, Z = 4, Dc = 1.575 mg·m-3, μ = 0.192 mm-1, F(000) = 584, and final R1 = 0.0349, ωR2 = 0.1212. Structural analysis shows that the Mg(II) center is six-coordination with a NO5 distorted octahedral coordination environment. The Mg(II) complex forms 1D chain structure by the interaction of hydrogen bonds and π-π stacking.
BIOACCUMULATION OF HEAVY METALS BY BACILLUS MEGATERIUM FROM PHOSPHOGYPSUM WASTE
IOANA ADRIANA STEFANESCU(*)
The aim of present study was to characterize the bioaccumulation capacity of heavy metals by Bacillus megaterium from phosphogypsum waste. The Bacillus megaterium strain (BM30) was isolated from soil near the phosphogypsum (PG) dump. For the bioaccumulation quantification produced by BM30 strain were used three experimental treatments respectively with 2, 6 and 10 gL-1 PG. Cellular biomass samples were collected punctually at ages corresponding to the three stages of the development cycle of the microorganism: exponential phase, stationary phase and decline phase and the heavy metals concentrations were measured by atomic absorption spectroscopy. The bioaccumulation yields in cell biomass, relative to the total amount of analyte introduced in the reaction medium were between 20 - 80 %, the lowest value was recorded by Cu and highest by Mn. The study results indicated that the isolated strain near the dump PG, BM30, bioaccumulate heavy metals monitored in cell biomass in the order Cu > Fe > Zn = Mn.