Volume 18, No. 3 (2017)
Articles
COMPARATIVE STUDY OF CHEMICAL COMPOSITION, PHYSICO-CHEMICAL AND ANTIOXIDANT PROPERTIES OF OILS EXTRACTED BY TRADITIONAL AND HEXANE METHODS FROM TERMINALIA CATAPPA L. KERNELS
Bérenger A. L. Ladele(1), Salomé D. S. Kpoviessi(1*), Fidele Assogba(2)
The comparative study of physico-chemical characteristics of Terminalia catappa L. kernel oils extracted by two methods has been done. The oil yields were 28.13 % and 61.78 % respectively for traditional and hexane methods and the fatty acid profiles showed palmitic acid (40.79 % and 40.03 % respectively) oleic acid (25.55 % and 26.09 % respectively), linoleic acid (26.72 % and 26.64 % respectively) and stearic acid (4.35 % and 4.49 % respectively) as major components. The oils extracted by the two ways showed similar physico-chemical properties, good calorific values and non-toxicity against Artemia salina L. Oil obtained by traditional method exhibited more antioxidant capacity (1.40) than the hexane one (0.15). This traditional method helps to extract 45 % of the total oil. It gives oil free of organic solvent, with good physico-chemical properties that could be useful as edible oil and for industrial applications.
PREPARATION AND PROPERTIES OF THREE NEUTRAL COPPER (I) COMPLEXES BASED ON BIS[2-(DIPHENYLPHOSPHINO)PHENYL]ETHER) PHENYL] ETHER AND SUBSTITUTED IMIDAZOLE-2,9-DIMETHYL-1,10-PHENANTHROLINE
Xin Fang Liu(*), Rong Fang Li, Xun Feng(*)
With deprotonated 2-(4-nitro phenyl)-, 2-(4-methyl phenyl)-, and 2-(4-methoxy phenyl) imidazoled-2,9-dimethyl-1,10-phenanthroline (NPIP, MPIP and MoPIP) as nitrogen ligands, as well as bis[2-(diphenylphosphino) phenyl]ether (DPEphos) as phosphorus ligand, three Cu(I) neutral complex has been synthesized and characterized by infrared spectroscopy (IR), elemental analysis and 1H NMR methods. TG-DTA shows that the complex begins to decompose when the temperature reached about 220 oC, indicating their high thermo-stability. The emission spectrum shows that the complexes exhibit yellow emission with a peak emission wavelength of 576, 585 and 596 nm under excitation of 287 nm in powder state.
EVALUATION OF SURVIVABILITY AND BIOACTIVITY OF SACCHAROMYCES CEREVISIAE IN BREAD DOUGH
Zahra Kasaie(1*), Aziz Homayouni Rad(2), Mina Kargozari(3), Mahsa Jahanbakhsh Oskouie(4)
One of the most significant current discussions in dough fermentation is survivability and bioactivity of Saccharomyces cerevisiae. In this study, four samples of instant dry yeast (all the yeast strains are active dry type) were evaluated by epifluorescence light microscopy using 0.2 % fluorescein diacetate. Microbial tests were carried out in order to count the number of viable cells yeast. Gasograph used to measuring CO2 produced during fermentation. Bread volume and height were assessed. Yeast (A) had the highest number of green cells (178 ± 7) due to its more bioactivity as compared to types B, C and D (P
TRACE MEASUREMENT OF CO, CH4, AND CO2 IN HIGH PURITY GASES BY GC-FID-METHANIZER: METHOD VALIDATION AND UNCERTAINTY ESTIMATION
Harry Budiman, Oman Zuas(*)
In this study, method validation and uncertainty estimation for the measurement of trace amounts gas impurities such as carbon monoxide (CO), methane (CH4), and carbon dioxide (CO2) using gas chromatography flame ionization detector with methanizer (GC-FID-methanizer) are reported. The method validation was performed by investigating the following performance parameters such as selectivity, limit of detection (LOD), limit of quantification (LOQ), precision, linearity, accuracy, and robustness. The measurement uncertainty to indicate the degree of confidence of the analytical results was estimated by using a bottom up approach. The results reveals that the method possess good repeatability (% relative standard deviation RSD < 1 %) and intermediate precision (RSD % < 5 %) properties for the measurement of trace level CO, CH4, and CO2. No bias was found for the validated method. The linearity of the method was found to be remarkable with correlation coefficient (R2) higher than 0.995 for all target analytes. In addition, the measurement uncertainty of the CO, and CO2 in high purity helium (He) gas sample measured using the validated method were found to be 0.08 µmol∙mol-1, and 0.11 µmol∙mol-1, respectively, at 95 % of confidence level. No measurement uncertainty was obtained for CH4 in high purity gas sample due to its concentration was below the GC-FID-methanizer detection level. In conclusion, the GC-FID-methanizer under experimental condition of this study is reliable and fit for the measurement of trace levels of CO, CH4 and CO2 in high purity gas samples.
ANTIOXIDANT CAPACITY, MINERAL CONTENT AND ESSENTIAL OIL COMPOSITION FROM SELECT ALGERIAN MEDICINAL PLANTS
Hadjira Guenane(1*), Abdelaziz Gherib(2), Boulanouar Bakchiche(1), Ángel A. Carbonell-Barrachina(3), Francisca Hernández(4), Marina Cano-Lamadrid(3)
The objective of the present study was to analyze the total antioxidant capacity, minerals contents of four plants (Juniperus oxycedrus, Thymus capitatus, Laurus nobilis and Eruca vesicaria) and chemical composition of the essential oils of the aerial parts of T. capitatus. Their antioxidant activity was assessed by DPPH, ABTS and FRAPS assays. Total phenol and flavonoid contents of the extracts were also determined. The results showed that the L. nobilis extract had the highest total phenolic and flavonoids contents (19.11 ± 0.22 mg GAE·g-1 dw, 4.47 ± 0.12 mg QE·g-1 dw, respectively). The extract of E. vesicaria had the highest value of TEAC for scavenging DPPH, whereas L. nobilis extract was active for ABTS and FRAP. GC/MS analysis revealed that the essential oil from the aerial parts of T. capitatus contained thirty-seven compounds; thymol was the major constituent (82.79 %). Atomic absorption spectroscopy showed high levels of Ca, K, Mg and Fe, and trace amounts of Zn, Cu and Mn in all four extracts.
METHODS OF ANALYSIS AND CLASSIFICATION OF THE COMPONENTS OF GRAIN MIXTURES BASED ON MEASURING THE REFLECTION AND TRANSMISSION SPECTRA
Artem O. Donskikh(*), Dmitry A. Minakov, Alexander A. Sirota, Vladimir A. Shulgin
The paper considers methods of classification of grain mixture components based on spectral analysis in visible and near-infrared wavelength ranges using various measurement approaches - reflection, transmission and combined spectrum methods. It also describes the experimental measuring units used and suggests the prototype of a multispectral grain mixture analyzer. The results of the spectral measurement were processed using neural network based classification algorithms. The probabilities of incorrect recognition for various numbers of spectral parts and combinations of spectral methods were estimated. The paper demonstrates that combined usage of two spectral analysis methods leads to higher classification accuracy and allows for reducing the number of the analyzed spectral parts. A detailed description of the proposed measurement device for high-performance real-time multispectral analysis of the components of grain mixtures is given.
SYNTHESIS OF BIODIESEL ON A HYBRID CATALYTIC-PLASMA REACTOR OVER K2O/CaO-ZnO CATALYST
Luqman Buchori, Istadi Istadi(*), Purwanto Purwanto
This paper aimed to study the synergistic effects of dielectric barrier discharge plasma and 5 % K2O/CaO-ZnO catalyst on biodiesel synthesis. The catalyst was prepared using co-precipitation followed by impregnation method. The catalyst was characterized by XRD, while the catalyst basicity was tested by titration method. The effects of voltage, weight hourly space velocity (WHSV), and catalyst pellet diameter on the yield of fatty acid methyl ester (FAME) and biodiesel were studied. The transesterification process within and without plasma environment was investigated to find synergistic effect between the role of high energetic electrons from the plasma through the catalytic reaction zone and the role of basicity in the catalyst. From the results, an applied voltage of 5 kV, a WHSV of 1.186 min-1, and a catalyst diameter of 5 mm gave the better FAME yield of 77.19 %. The reaction time required was only 1.25 minutes at a discharge power of 530 W. This result proved that the plasma environment has a significant effect on performance of the hybrid catalytic-plasma reactor for biodiesel production.
AN INDEXING APPROACH FOR THE ASSESSMENT OF HEAVY METALS IN DRINKING WATER PRODUCED BY MAURITANIAN WATER TREATMENT PLANT
Brahim Baba Aloueimine(1, 2*), Mohamed Ould Kankou(2), Driss Belghyti(1)
In the present work, the assessment of drinking water quality was carried out through a monitoring of heavy metals in the treated and consumed waters in the city of Nouakchott (Mauritania). Monthly sampling was conducted for a period of 24 months between January 2012 and December 2013. Nine parameters were evaluated: pH, T (°C), Turbidity (NTU), Al, Fe, Cu, Mn, Al2(SO4)3 and CaO. Indexing approaches have been applied by calculating the Heavy Metal Pollution Index (HPI) and Metal Index (MI) for the assessment of influence of heavy metals on the overall quality of water. The obtained results for heavy metals are in good agreement with World Health Organization (WHO) standards. Though the aluminum concentration remains in the limits set by WHO, yet it shows a major contribution in the indices. This has been verified by the statistical analysis which demonstrates fair correlations between aluminum, HPI (r = 0.9) and MI (r = 0.77). Aluminum showed the important influence of seasonal change in the year as well as the doses of reagents injected during the treatment process on the concentration of aluminum is detailed.
STUDIES AND RESEARCH CONCERNING THE USE OF SOME RECYCLABLE ABSORBENT MATERIALS FOR INCREASING ACOUSTIC COMFORT INTO A ROOM DESIGNED FOR SPEAKING
Florin Marian Nedeff(1*), Narcis Bârsan(1), Adriana Luminița Fînaru(2)
The acoustic comfort of a speech hall is characterized by acoustic parameters. These parameters depend by on the hall volume, construction and design materials. On the hall ceiling (the most unused surface), some various acoustic devices can be installed on which the acoustic materials can be applied in order to obtain specific suitable acoustic parameters for that hall. Recycled materials such as wood, granular recycled rubber, shredded recycled plastic and shredded polypropylene, applied on various acoustic devices made from OAS, polystyrene or plasterboard rigips, can increase the acoustics quality of room.
QUANTIFICATION OF OCHRATOXIN A IN MOLDAVIAN WINES
Rodica Sturza(1), Olga Lazacovici(1,2*)
The level of the carcinogenic mycotoxin ochratoxin A (OTA) in wines produced in Moldova, including bottled and raw material wines, was analyzed by enzyme-linked immunosorbent assay (ELISA) and high performance liquid chromatography (HPLC) analysis with fluorescence detection after immunoaffinity column clean-up. The study was conducted on wine samples from vintage 2006 - 2016. Our results confirm previously published reports that the levels of OTA are considerably higher in red wines than those in white ones. It was found that OTA levels of analyzed samples differ significantly depending on the harvest year of the wine. Thus, 48 % of studied wine samples from vintage 2006 were contaminated with OTA, including 10 % samples with concentration of OTA higher than 2 µg‧L-1. In contrast, levels of OTA detected in samples from 2016, haven’t exceed 0.05 µg‧L-1 (quantification limit of HPLC method).