Chemistry Journal of Moldova

2009 Volume 4, no.2

COMPARISON OF SENSITIVITY OF ANALYTICAL METHODS FOR SAMPLES INJECTION IN THE DETECTION OF COMPOUNDS WITH FLAVOURING POTENTIAL OF WINES

Author(s):

Rodica Sturza, Constantin Sîrghi, Mariana Vrîncean, Susanne Böhme


Field: Food chemistry
Type: Research paper
Issue: 2009 Volume 4, no.2
Pages: 50-59
Keywords: GC/MS, Head-space, SPME, Wine and Flavours.
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DOI:
dx.doi.org/10.19261/cjm.2009.04(2).11

Graphical Abstract: 
The study has been focused on the comparative analysis of various analytical techniques for the injection of samples applied to detect the additives with flavouring potential that are used to obtain illicitly the "Muscat" and "Isabela" wines, by implementing the GC/MS method with injection of liquid samples directly into the capillary column, using the "Head-space" method and the solid phase microextraction (SPME).

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THE CONTENT OF OCHRATOXIN A IN MOLDAVIAN WINE PRODUCTS

Author(s):

Boris Găină, Rodica Sturza, Violeta Bejan, Constantin Bodean


Field: Food chemistry
Type: Research paper
Issue: 2009 Volume 4, no.2
Pages: 44-49
Keywords: mycotoxin, OTA, wine, grape juice.
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DOI:
dx.doi.org/10.19261/cjm.2009.04(2).12

Graphical Abstract:
 The basic objective of this work is studying the content of ochratoxin A (OTA) in grapes, grape juice, and wine. This is an analysis of their origin, the conditions of contamination and ways decontamination, toxiconogenes mushrooms, toxicity, world and European regulations. It was estimated the methods of detection of mycotoxins in wine products. It has examined the contents of OTA in the Moldavian juice/wine from different varietals at different stages of winemaking and obtained by different proceeds winemaking.

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PREPARATION OF MICROBIOLOGICAL AGENTS FOR ORGANIC POLLUTANTS REMOVAL IN WASTEWATER

Author(s):

Angela G. Cincilei, Svetlana A. Tolocichina, Inna O. Rastimesina, Ion P. Dragalin, Veronica Dumbraveanu, Nina V. Streapan, Vera C. Mamaliga


Field: Ecological chemistry
Type: Research paper
Issue: 2009 Volume 4, no.2
Pages: 40-43
Keywords: Benzothiazoles, biodegradation, immobilized cells, Rhodococcus sp.
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DOI:
dx.doi.org/10.19261/cjm.2009.04(2).13

Graphical Abstract:
 The authors have investigated the biochemical aspects of degradation processes of persistent organic compound benzothiazole by immobilized Rhodococcus rhodochrous cells, such as entrapped in Ca-alginate beads, or as being immobilized on some solid carries. The mineralization of toxicant was complete and biodestructive capacity of entrapped in alginate bacteria increased with each new experimental cycle.

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EFFECT OF COMPLEX FORMATION ON ELECTROCHEMICAL BEHAVIOUR OF METAL-CONTAINING WASTE WATERS

Author(s):

Olga Covaliova


Field: Ecological chemistry
Type: Research paper
Issue: 2009 Volume 4, no.2
Pages: 34-39
Keywords: electrochemical processes, model plating solutions, ligands, complex salts, polarization curves.
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DOI:
dx.doi.org/10.19261/cjm.2009.04(2).14

Graphical Abstract:
 The problem of preventing the heavy metals and other toxic substances release in environment due to the discharges of untreated plating and rinsing solutions is actual from both ecologic and economic point of view. It is crucial to prevent the environmental pollution and uncontrolled losses of resources (metals and other substances). The treatment technologies used today are not always efficient and cost saving and in some cases they
may even provoke the secondary pollution of environment. Electrochemical treatment of industrial waste waters is one of the most promising technologies as it implies the same principles as the main technological processes and does not require introducing of chemicals into the treated solution. However, until now this method was given insufficient attention, although there are certain publications in this field [1].

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REACTIVE EXTRACTION OF TARTARIC ACID

Author(s):

Natalia Marchitan


Field: Ecological chemistry
Type: Research paper
Issue: 2009 Volume 4, no.2
Pages: 28-33
Keywords: reactive extraction, tartaric acid, Amberlite LA-2.
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DOI:
dx.doi.org/10.19261/cjm.2009.04(2).15

Graphical Abstract:
 The present paper describes the results of reactive extraction of tartaric acid in model systems, which can be used for its separation from secondary wine products. As extractant have been used a normal/isododecyl mixed secondary amine Amberlite LA-2. The following parameters of the separation process have been varied: nature of diluent and modifier; modifier concentration; concentration, temperature and pH of the tartaric acid solution and the stirring time, and the work intervals have been established. It was concluded that in determinated conditions the extent of tartaric acid extraction attains value 85-95%.

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ADSORPTION WAVE OF VANADIUM COMPLEX WITH 2,3–DIHYDROXYBENZALDEHYDE

Author(s):

Ludmila Kiriyak, Natalia Cecoi, Tatiana Cazac, Mihail Revenco


Field: Analytical chemistry
Type: Research paper
Issue: 2009 Volume 4, no.2
Pages: 24-27
Keywords: Voltammetry, 2,3–dihydroxybenzaldehyde, vanadium.
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DOI:
dx.doi.org/10.19261/cjm.2009.04(2).16

Graphical Abstract:
 The polarographic behavior of the complex formed by V(V) and 2,3–dihydroxybenzaldehyde (2,3–DHBA) in the solution containing acetate buffer (pH 5,2) has been investigated. By means of a.c. polarography, chronovoltammetry and other techniques, it has been shown that the electrode process is complicated by the adsorption of 2,3-DHBA and its vanadium complex. The kinetic and adsorption parameters of the electrode process have been determined: adsorption equilibrium constant B= 1,32⋅105 mol-1⋅dm3, the attraction constant γ = 1,2, the maximum surface concentration Гmax = 9,10⋅10-11 mol⋅ cm-2; the share of the electrode surface occupied by one particle of the adsorbed complex S = 1,81 nm2 and the free adsorption energy ΔG = - 39,1 kJ· mol-1.

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(-)-DRIMENOL – A VALUABLE STARTING COMPOUND FOR THE SYNTHESIS OF DRIMANIC SESQUITERPENOIDS

Author(s):

Aculina Aricu


Field: Natural product chemistry and synthesis
Type: Review
Issue: 2009 Volume 4, no.2
Pages: 14-23
Keywords: drimenol, albicanol, drimenyl acetate, polygodial, warburganal, synthesis.
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DOI:
dx.doi.org/10.19261/cjm.2009.04(2).17

Graphical Abstract:
 (-)-Drimenol is a relatively accessible compound, that has been and may be further used as a starting material to prepare sesquiterpenoids. The present review deals with the methods of obtaining of this compound as well as its usage.

Downloads: 35

EPITHERMAL NEUTRON ACTIVATION ANALYSIS FOR BACTERIAL TRANSFORMATIONS OF CHROMIUM

Author(s):

N.Ya. Tsibakhashvili, L. Mosulishvili, E. Kirkesali, T. Kalabegishvili, S. Kerkenjia, M.V. Frontasyeva, Gh. Duca , I. Zinicovscaia


Field: Ecological chemistry
Type: Review
Issue: 2009 Volume 4, no.2
Pages: 8-13
Keywords: neutron activation analysis, electron spin resonance spectrometry, Arthrobacter.
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DOI:
dx.doi.org/10.19261/cjm.2009.04(2).18

Graphical Abstract:
 Most powerful primary analytical technique, neutron activation analysis, was applied to study indigenous bacteria, namely, Arthrobacter genera  which can be successfully used in detoxification and immobilization of toxic substances. In the present study the effect of Cr(VI) on the elemental content of these bacteria has been examined. The concentrations from 12 to 19 elements such as Na, Al, Cl, K, Fe, Co, Zn, As, Br, Rb, Sr, Sb, Ba, Tb, Th, U were determined in the bacterial cells. The high rate of Cr accumulation in the tested bacterial cells was shown. In bacteria treated with  chromate some similarity in the behaviour of the following essential elements − potassium, sodium, chlorine − was observed. Such non-essential elements as Ag, As, Br and U were determined in all bacteria and have to be considered by cells as toxins.

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