JSCS Vol 68, No. 12
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Ageing-induced changes of reduced and oxidised
glutathione in fragments of maize seedlings
VESNA D. DRAGICEVIC, SLOBODANKA SREDOJEVIC, MIHAJLO B. SPASIC* and MIROSLAV M.
VRVIC**
Maize Research Institute
“Zemun Polje”, 11185 Belgrade-Zemun, Slobodana Bajica 1,
*Institute for Biological Research “Sinisa Stankovic”, 11000 Belgrade, 29.
Novembra 142 and
**Faculty of Chemistry, University of Belgrade, 11001 Belgrade, Studentski trg
16, P. O. Box 158, Serbia and Montenegro
(Received 15 April 2003)
A trial with four maize inbred lines with the
ability to have different durations of seed germination in the course of the
accelerated ageing (AA) treatment was set up. Changes of the content of total,
reduced and oxidized glutathione (expressed as monomers) were observed in the
seeds and seedlings before and after the treatment. For the first time, changes
of glutathione in whole seedlings, as well as in the rest of the seed, were
analysed. It was noticed that maize inbreds with a smaller decrease of the
total glutathione but with an increase of the oxidized form had the ability of
prolonged germination. In the control seedlings, the AMount of total
glutathione was lower than in the treated ones. Maize seeds which lost
germination faster had greater losses of total glutathione with an increased
content of the oxidized form in seedlings. The ability of prolonged germination
together with the possibility of glutathione synthesis in seedlings are
genotypic traits.
Keywords: ageing, maize seedling, reduced and oxidised gluthatione.
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Transition metal complexes with
thiosemicarbazide-based ligands.
Part 46. Synthesis and physico-chemical characterization of mixed ligand
cobalt(III)-complexes with
salicylaldehyde semi-, thiosemi- and isothiosemicarbazone and pyridine
VUKADIN M. LEOVAC , LJILJANA S. VOJINOVIC, KATALIN MÉSZÁROS SZÉCSÉNYI and
VALERIJA I. CESLJEVIC
Department of Chemistry,
Faculty of Science, University of Novi Sad, Trg Dositeja Obradovi}a 3, 21000
Novi Sad, Serbia and Montenegro
(Received 25 June,
revised 12 September 2003)
Abstract: Mixed ligand octahedral cobalt(III)
complexes with the tridentate salicylaldehyde semi-, thiosemi- and
isothiosemicarbazone and pyridine of general formula [CoIII(L11-3)(py)3]X
(H2L1 = salicylaldehyde semicarbazone, X = [CoIICl3(py)]-,
ClO4- . H2O, I- . 0.5 I2;
H2L2 = salicylaldehyde thiosemicarbazone, X = [CoIICl3(py)]-,
[CoIIBr3(py)]-, ClO4- . H2O,
I3-; H2L3 = salicylaldehyde
S-methylisothiosemicarbazone, X = [ CoIIBr3(py) ]-, ClO4-
. H2O, BF4-) were synthesized. The tridentate
coordination of all the three dianionic forms of the ligands involves the
phenol oxygen, hydrazine nitrogen and the chalcogen (O or S) in case of
salicylaldehyde semi-, thiosemicarbazone and the terminal nitrogen atom in the
case of isothiosemicarbazone. For all the complexes, a meridial octahedral
arrangement is proposed, which is a consequence of the planarity of the chelate
ligand. The compounds were characterized by elemental analysis, molar
conductivity, magnetic susceptibility, IR and electronic absorption spectra. The
thermal decomposition of the complexes was investigated by thermogravimetry,
coupled TG-MS measurements and DSC.
Keywords: mixed Co(III) complexes, salicylaldehyde semi-, thiosemi-,
isothiosemicarbazone, pyridine.
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Transition metal complexes with
thiosemicarbazide-based ligands.
Part 47. Synthesis, physicochemical and voltAMmetric characterization of
iron(III) complexes with
pyridoxal semi-, thiosemi- and S-methylisothiosemicarbazones
VIOLETA S. JEVTOVIC, LJILJANA S. JOVANOVIC, VUKADIN M. LEOVAC and LUKA J.
BJELICA
Faculty of Science,
University of Novi Sad, Trg D. Obradovi}a 3, 21000 Novi Sad, Serbia and
Montenegro
(Received 14 July 2003)
The reaction of warm EtOH solutions of FeX3·nH2O
(X = Cl, NO3) with tridentate ONX (X = O, S, N) pyridoxal semi-, thiosemi- and S-methylisothiosemicabazones
(H2L1, H2L2, H2L3,
respectively) yielded high-spin octahedral mono- and bis(ligand) complexes of
the formula [Fe(H2L1-3)Cl2(H2O)]Cl,
[Fe(HL1,2)2]Cl·nH2O and [Fe(H2L3)(HL3)](NO3)2·H2O.
The compounds were characterized by elemental analysis, conductometric and
magnetochemical measurements, IR and UV-Vis spectra. Besides, a detailed
voltAMmetric study of the complexes was carried out in DMF solution in the
presence of several supporting electrolytes, to characterize the nature of the
electrode processes and solution equilibria.
Keywords: iron(III) complexes, pyridoxal semi-, thiosemi- and
isothiosemicarbazones, physicochemical and voltAMmetric studies.
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N O T E
Note on the Hyper-Wiener Index
IVAN GUTMAN, BORIS FURTULA and JASMINA BELIC
Faculty of Science,
University of Kragujevac, P. O. Box 60, 34000 Kragujevac, Serbia and Montenegro
(Received 7 July 2003)
The hyper-Wiener index WW of a chemical tree T is defined as the
sum of the products n1n2, over all pairs u,
u of vertices of T, where n1 and n2 are the
number of vertices of T, lying on the two sides of the path which
connects u and u. We exAMine a slight
modification WWW of the hyper-Wiener index, defined as the sum of the
products n1n2n3, over all
pairs u, u of vertices of T, where
n3 is the number of vertices of T, lying between u
and u. It is found that WWW correlates
significantly better with various physico-chemical properties of alkanes than WW.
Lower and upper bounds for WWW, and an approximate relation between WWW
and WW are obtained.
Keywords: hyper-Wiener index, Wiener index, chemical trees, alkanes.
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Hyper-Wiener index and Laplacian spectrum
IVAN GUTMAN
Faculty of Science,
University of Kragujevac, P. O. Box 60, 34000 Kragujevac, Serbia and Montenegro
(Received 7 July 2003)
Abstract: The hyper-Wiener index WWW of a
chemical tree T is defined as the sum of the product n1 n2
n3, over all pairs u, u of vertices of T,
where n1 and n2 are the number of vertices
of T, lying on the two sides of the path which connects u and u, and n3 is the number of vertices lying between
u and u. An expression enabling
the calculation of WWW from the Laplacian eigenvalues of T has
been deduced.
Keywords: hyper-Wiener index, Wiener index, Laplacian spectrum, chemical
trees, alkanes.
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Influence of the synthesis conditions on the
photoluminescence of silica gels
IVANA HINIC, GORAN STANICIC and ZORAN POPOVIC
Institute of Physics,
Pregrevica 118, 11000 Belgrade, Serbia and Montenegro
(Received 2 July 2003)
The photoluminescence spectra of silica xerogel
sAMples synthesized with ethanol as solvent and xerogel where the ethanol was
exchanged by water before drying are reported. In addition, the
photoluminescence spectrum of a silica cryogel synthesized with tert-butanol
as solvent was investigated. The sAMples were modified by formAMide. Bands at
2.00, 2.20, 2.32 and 2.46 eV were identified. In the photoluminescence spectra
of all sAMples. The band at 2.00 eV is caused by the presence of silane, and
the band at 2.20 eV is connected with the nonstoichiometric composition of
silica. The photoluminescence band at 2.32 eV was found to originate from the
organic groups of the solvent. The origin of this band are E’ defect centers,
which is a prominenet parAMagnetic defect in conventional a – SiO2.
Keywords: silica gel, luminescence, infrared
spectroscopy.
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Direct photolysis and photocatalytic degradation
of 2-AMino-5-chloropyridine
BILJANA F. ABRAMOVIC, VESNA B. ANDERLUH, ANDJELKA S. TOPALOV and FERENC F. GAÁL
Department of Chemistry,
Faculty of Science, Trg D. Obradovica 3, 21000 Novi Sad, Serbia and Montenegro
(e-mail: abrAMovic@ih.ns.ac.yu)
(Received 23 June 2003)
The direct photolysis
and photocatalytic degradation of a pyridine pesticide analogue,
2-AMino-5-chloropyridine, were investigated employing different analytical
techniques – potentiometry, for monitoring the pH and chloride generation,
spectrophotometry, for studying the degradation of the pyridine moiety, ion
chromatography, for monitoring nitrate formation, and total organic carbon
analysis for investigating the efficiency of the process. The photocatalytic
degradation was studied in aqueous suspensions of titanium dioxide under
illumination by UV light. It was found that chloride evolution was a zero-order
reaction which takes place by direct photolysis, in that way differing from the
degradation of the pyridine moiety, which takes place in the presence of
titanium dioxide. Changes in pH during degradation indicate the formation of
acidic intermediates and nitrate in addition to chloride. The effect of the
initial substrate concentration was also investigated by monitoring the
reaction of chloride generation as well as the degradation reaction of the
pyridine moiety. It was found that degradation of the parent compound (2.5
mmol/dm3) by direct photolysis is completed in about 20 minutes, and
of the pyridine moety by photocatalytic degradation in about nine hours. Based
on the obtained data a possible reaction mechanism is proposed.
Keywords: direct photolysis, photocatalytic degradation, titanium dioxide,
2-AMino-5-chloropyridine, water treatment.
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Normal-phase high performance liquid
chromatography of estradiol derivatives on AMino- and diol- columns
MARIJANA M. ACANSKI
Department of General and Inorganic Chemistry, Faculty of Technology,
University of Novi Sad, Bulevar cara Lazara 1,
21000 Novi Sad, Serbia and Montenegro (e-mail: marijana@tehnol.ns.ac.yu)
(Received 7 April,
revised 13 August 2003)
Abstract: The retention behaviour of estradiol
derivatives was studied by HPLC on chemically bonded polar stationary phases:
commercially available AMino- and diol- columns, as a function of the
heptane-propan-1-ol as the mobile phase, when the volume fraction of
propan-1-ol in the binary mobile phase was low, even less than 5 %. The relationship
between the logarithm of the retention constant (log k) and the
logarithm of the volume fraction of propan-1-ol (–log j) in the eluent was linear for all solutes studied. The results
are discussed in terms of the solute and stationary phase properties and
compared with the results of the sAMe derivatives obtained in earlier
investigations.
Keywords: HPLC, AMino- and diol- columns, non-aqueous eluent, estradiol
derivatives, retention behaviour.
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