bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Counterions on the Interaction of Pyridinium Salts with Model Membranes
Authors: Sarapuk Janusz , Kleszczyńska Halina , Pernak Juliusz , Kalewska Joanna , Różycka-Roszak Bożenna
Published: February 2015

The interaction of pyridinium salts (PS) with red blood cells and planar lipid membranes was studied. The aim of the work was to find whether certain cationic surfactant counterion influence its possible biological activity. The counterions studied were Cl- , Br-, I-, ClO4
-, BF4- and NO3
-. The model membranes used were erythrocyte and planar lipid membranes (BLM). At high concentration the salts caused 100% erythrocyte hemolysis (C 100) or broke BLMs (CC). Both parameters describe mechanical properties of model membranes. It was found that the efficiency of the surfactant to destabilize model membranes depended to some degree on its counterion. In both, erythrocyte and BLM experiments, the highest efficiency was observed for Br-, the lowest for NO3
-. The influence of all other anions on surfactant efficiency changed between these two extremities; that of chloride and perchlorate ions was similar. Some differences were found in the case o f BF4
- ion. Its influence on hemolytic possibilities of PS was significant while BLM destruction required relatively high concentration of this anion. Apparently, the influence of various anions on the destructive action of PS on the model membrane used may be attributed to different mobilities and radii of hydrated ions and hence, to different possibilities of particular anions to modify the surface potential of model membranes. This can lead to a differentiated interaction of PS with modi­fied bilayers. Moreover, the effect of anions on the water structure must be taken into ac­count. It is important whether the anions can be classified as water ordering kosmotropes that hold the first hydration shell tightly or water disordering chaotropes that hold water molecules in that shell loosely.
Molecular Characterization and Taxonomic Affinities of Species of the White Rot Fungus Ganoderma
Authors: Sokoł Slawomir , Kaldorf Michael , Bothe Hermann
Published: February 2015

The systematic affinities of Ganoderma have largely been resolved in the extensive publications of Moncalvo and coworkers (Moncalvo et al., 1995a, b; Hseu et al., 1996). The present communication adds further sequences of the ITS1 region of Ganoderma isolates from Po­ land and corrects some of the classifications of Ganoderma species. The sequence data indicate that G. australe and G. adspersum are different species. Both morphological and molecular data are in accord with an interspecific separation of G. pfeifferi and G. resinaceum. The ITS1 region is particularly suited for the taxonomic segregation of Ganoderma by molecular methods.
Salt and Drought Stress Differentially Affect the Accumulation of Extracellular Proteins in Barley
Authors: Ramanjulu Sunkar , Kaiser Werner , Dietz Karl-Josef
Published: February 2015

Barley (Hordeum vulgare) was grown for eight days in the presence of a range of salt concentrations or subjected to repeated cycles of wilting and rehydration. Changes in apoplastic protein content, protein pattern, enzymic activities and ion composition were in­ vestigated under salinity and drought. The protein content of intercellular washing fluid (IWF) increased 2.5-to 3.0-fold when the NaCl concentration in the growth medium was increased from 0 to 100 mᴍ. The elevated protein content was the result of a general increase in most polypeptides and a pronounced increase in the abundance of specific polypeptides of apparent molecular masses of 15, 21, 22, 26, 36, 40 and 62 kDa. Conversely, the IWF protein content decreased during wilting similar as after application of colchicin, cytochalasin B or cycloheximide suggesting that inihibition of protein synthesis or vesicle transport may be the cause for the decrease in apoplastic protein content and enzyme activities in dehydrating plant tissue. The changes in apoplastic protein content were accompanied by stress-specific alterations in activities of apoplastic enzymes. The greater apoplastic protein content was the consequence of stimulated protein synthesis in the presence of NaCl, as evidenced by increased incorporation of [35S]-methionine into IWF protein. The results demonstrate that the leaf apoplast is a compartment which sensitively and differentially responds to drought and salinity with consequences for plant growth.
In Vivo and in Vitro Studies on the Regulatory Link between 3-Hydroxy-3- methylglutaryl Coenzyme A Reductase and Cholesterol 7α-Hydroxylase in Rat Liver
Authors: Boll Meinrad , Weber Lutz W. D. , Plana Juliana , Stampfl Andreas
Published: February 2015

The activities of 3-hydroxy-3-methylglutaryl CoA reductase (HMGCoA reductase; EC 1.1.1.34), rate-limiting enzyme of cholesterol biosynthesis, and cholesterol 7α-hydroxylase (EC 1.14.13.17), key enzyme of the neutral bile acid synthesis pathway, were measured in the microsomal fraction of rat liver and in rat liver cells to investigate the coordinate regulation of the two pathways.

Both enzyme activities exhibited the same diurnal rhythm and responded in a coordinate fashion to fasting or bile acid-feeding (decrease) and to cholestyramine-feeding (increase). Cholesterol-feeding decreased the activity of HMGCoA reductase, increased that of cholesterol 7α-hydroxylase, and concomitantly increased free cholesterol in microsomes.

In an ex vivo setting using primary hepatocytes from animals fed a high cholesterol diet the activity of HMGCoA reductase was initially low and that of cholesterol 7α-hydroxylase was elevated. Release of cholesterol into the medium with ongoing incubation caused HMGCoA reductase activity to increase, and that of cholesterol 7α-hydroxylase to decline. Incubation of hepatocytes with a cholesterol-containing lipoprotein fraction stimulated the activity of cholesterol 7α-hydroxylase, but left HMGCoA reductase activity unaffected.

The results confirm the idea of a joint regulation of the two key enzymes of cholesterol metabolism in response to the levels of substrate and metabolites, and support the notion that with respect to bile acid and cholesterol levels, respectively, regulation of HMGCoA reductase activity may be secondary to that of cholesterol 7α-hydroxylase. The in vitro studies supply evidence that the effects of cholesterol and bile acid excess or deficiency are direct and do not involve accessory changes of hormone levels or mediators.
Phytochemical Evidence for the Plant Origin of Brazilian Propolis from São Paulo State
Authors: Bankova Vassya , Boudourova-Krasteva Gergana , Sforcin Jose M. , Frete Xavier , Kujumgiev Atanas , Maimoni-Rodella Rita , Popov Simeon
Published: February 2015

Propolis and plant secretions from three species, most frequently mentioned as botanical sources of the bee glue in Brazil (Baccharis dracunculifolia, Araucaria angustifolia and Eucalyptus citriodora) have been investigated using GC-MS. Based on chemical evidence, B. dracunculifolia was shown to be the main propolis source in São Paulo state. The antibacterial and antifungal activities of all four materials were also tested, the most active being propolis and Baccharis leaf exudate.
Protective Effect of Quaternary Piperidinium Salts on Lipid Oxidation in the Erythrocyte Membrane
Authors: Kleszczyńska Halina , Oświęcimska Małgorzata , Sarapuk Janusz , Przestalski Stanisław , Witek Stanisław
Published: February 2015

A new series of amphiphilic compounds with incorporated antioxidant functional group has been investigated. Piperidinium bromides, differing in the alkyl chain length (8, 10, 12, 14 and 16 carbon atoms in the chain) were synthesised to protect biological and/or model membranes against peroxidation and following negative consequences. Their antioxidant activity was studied with erythrocytes subjected to UV radiation. The salts used inhibited lipid oxidation in the erythrocyte membrane. The degree of this inhibition depended on the alkyl chain length of the bromide used and increased with increasing alkyl chain length. A comparison of the results obtained for piperidinium bromides with those obtained for the widely used antioxidant 3,5-di-t-butyl-4-hydroxytoluene (BHT) revealed that only two shortest alkyl chain salts were less efficient than BHT in protecting erythrocyte membranes. A similar comparison with antioxidant efficiency of flavonoids extracted from Rosa rugosa showed that they protected the membranes studied more weakly than the least effective eight-carbon alkyl chain piperidinium bromide. The three compounds of longest alkyl chains were the most active antioxidants. Their activities did not differ significantly.
Pro-and Antioxidative Properties of Cortical Tissue Preparations from Human Brain Exhibiting NMDA-Receptor Characteristics
Authors: Elstner Matthias , Denke Andrea , Gsell Wieland , Elstner Erich F. , Riederer Peter , Gerlach Manfred
Published: February 2015

The effects of cortical tissue preparations (CTP) from human brain on the production of reactive oxygen species (ROS) has been investigated with several biochemical model reactions. As indicators for ROS, fragmentation of the methionine derivatives, α-keto-γ-methyl-thiobutyric acid (KMB) or 1-amino-cyclopropane-1-carboxylic acid (ACC), yielding ethene have been used. With these systems we have shown that production of OH-radical-type oxidants by the xanthine oxidase (XOD)-system is strongly stimulated by CTP. This activity is due to intrinsic iron ions since ethene formation from KMB is stimulated by EDTA , inhibited by desferrioxamine (DesferalR) and also visible with heat-denatured CTP. CTP by themselves have no XOD activity.

3-Hydroxykynurenine (3HK) is another possible substrate for XOD but produces H2O2 without XOD-catalysis, whereas allopurinol is not inhibiting. CTP contain measurable NAD(P)H oxidoreductase activity, producing OH-radical-type oxidants at the expense of NADPH and (to a lesser extent) NADH as electron donors , shown as redox-cycling of 2-methyl-5-hydroxy-1.4-naphthoquinone, plumbagin. Ethene formation from KMB is also driven by both morpholinosydnonimine (SIN) or ONOOH. The reaction driven by SIN is stimulated by CTP and inhibited by catalase, SOD and hemoglobin. Since ethene release from KMB driven by ONOOH is inhibited by CTP the mechanisms driving KMB fragmentation are different for SIN and ONOOH.

Furthermore CTP contain approx. 4 U catalase activity per mg protein and very weak peroxidase (POD) activity shown as ACC fragmentation yielding ethene in the presence of both H2O2 and KBr or NaCl. Since ACC binds to CTP and both compounds, ACC and KMB are natural products, present in food (ACC) or synthesized from methionine in vivo (KMB), these compounds may represent protecting agents in systems where reactive oxygen species are formed. One might even speculate that the production of ethene at these membrane receptor sites may have biological functions, since ethene is known to possess anaesthetic activities.
Kinetics of Thyroid Hormone Induced Changes in Liver and Skeletal Muscle Enzymes of Clarias batrachus
Authors: Tripathi G.
Published: February 2015

Kinetics of triiodothyronine (T3) induced changes were studied in cytoplasmic malate dehydrogenase (cMDH), mitochondrial malate dehydrogenase (mMDH) and lactate dehydrogenase (LDH) of the liver and skeletal muscle of a catfish, Clarias batrachus. The rates of gradual inductions in the activities of all the three metabolic enzymes were faster in skeletal muscle than those of the liver. These time-dependent and tissue-specific inductions may be due to the possible differences in the rates of different enzymic syntheses. The maximum inductions in the activities of cMDH, mMDH and LDH were recorded around 19 hr after T3 treatment. Thereafter, the activities of all the enzymes gradually declined to their half levels within the next 12 hr which reflected the physiological half-life of these metabolic enzymes in the freshwater catfish.
6,9-Dihydroxy-3(15)-caryophyllen-4,8-dione -a New Antibiotic from a Marasmius Species
Authors: Fabian Kerstin , Anke Timm , Sterner Olov
Published: February 2015

6,9-Dihydroxy-3(15)-caryophyllen-4,8-dione (1), a new cytotoxic caryophyllane sesquiterpene, was isolated from fermentations of a tropical Marasmius species. The structure was established by spectroscopic methods. 1 exhibits strong cytotoxic effects on different cell lines, but only weak antimicrobial activities. 1 weakly inhibits the incorporation of leucine and thymidine into proteins and DNA of mammalian cells and interferes with the aggregation of hum an and bovine platelets
Hypoxysordarin, a New Sordarin Derivative from Hypoxylon croceum
Authors: Daferner Michael , Mensch Sarah , Anke Timm , Sterner Olov
Published: February 2015

Hypoxysordarin (1), a new sordarin derivative, was isolated from the fermentation broth of the facultative marine Hypoxylon croceum together with a new y-lactone, hypoxylactone (2) and sordarin (3). The structures were determined by spectroscopic m ethods. Sordarin (3) has previously been isolated from the terrestrial Sordaria araneosa (Sordariaceae). Like the parent com pound hypoxysordarin exhibits high antifungal activities due to a specific inhibition of protein biosynthesis
Di-and Triterpenoids from the Liverwort Blepharidophyllum densifolium
Authors: Flegel Michael , Becker Hans
Published: February 2015

22 ent-kaurane and ent-pimarane type diterpenoids, ten of which are new, ent- 19-acetoxykaur- 16-en-15-one, ent-19-oxo-kaur-16-en-15-one, ent-11α-acetoxy-20-oxo-kaur-16-en-15-one, enf-11α-acetoxy-15-oxo-kaur-16-en-20-acid,-11α-acetoxy-7β-hydroxy-kaur-16-en-15-one, ent-11α-acetoxy-19-hydroxy-kaur-16-en- 15-one, ent-19-acetoxy-11α-hydroxy-kaur-16-en-15- one, ent-11α-acetoxy-6β, 19-dihydroxy-kaur-16-en-15-one, ent-11α-acetoxy-19-hydroxykauran- 15-one and em -19-acetoxy-11α-hydroxy-kauran-15-one were isolated from the liverwort Blepharidophyllum densifolium. Furthermore three known triterpenoids cabraleadiol, cabraleadiolacetate and shoreic acid have been found. Their structures were established by NMR spectroscopy
The Peroxidase of Dioscorea esculenta: Partial Purification and Characterisation
Authors: Okpuzor J. , Omidiji O.
Published: February 2015

Dioscorea esculenta. Peroxidase. Ion Exchange Chrom atography. Gel Filtration We isolated two types of peroxidase from the fresh tuber of Dioscorea esculenta using a combination of ion exchange and gel filtration chrom atography. The results showed one type to be neutral and the other to be strongly ionic. The strongly ionic type constitutes 70% of total peroxidase activity in the tissue. The apparent molecular weight of the neutral type is 38 kD a while the anionic type has an apparent molecular weight of 57 kD a. It was possible with the use of gel filtration on Sephadex G-200 followed by FPLC on phenyl superose to purify the lower size POD by a factor of 15, while the larger ionic peroxidase was purified 68 fold com pared to the crude with protein yields of 0.90% and 1.30% respectively. The ionic POD is m ore therm o-stable, has a higher optimum temperature for activity and has a higher ap parent activation energy com pared to the neutral POD from this source.
Photosynthesis and Heat Response of the Green Alga Micrasterias denticulata (Desmidiaceae)
Authors: Weiss Dagmar , Ltitz Cornelius , Lütz-Meindl Ursula
Published: February 2015

Cells of the green alga Micrasterias denticulata cultivated at 15 °C, 20 °C or 25 °C were exposed to heat shocks at different temperatures (30 -40 °C) for varying duration ( 5 - 90 m in). Cell pattern formation, division rate as well as photosynthesis and respiration by measuring oxygen production and consumption have been studied. The degree of cell shape malformations was found dependent on the preceding cultivation temperature along with the mode of the heat shock. Cells cultivated at 15 °C and 20 °C could counteract a 90 min heat shock at 35 °C much better than those cultivated at 25 °C, which was seen by a less reduced young semicell. Cells cultivated at 15 °C and 25 °C reveal a reduced division activity compared to those grown at 20 °C even with a marked retardation when affected by a preceding heat shock.

Photosynthesis and the level of plastid pigments (carotenoids, chlorophylls, β-carotene, lutein) of controls determined by HPLC analysis reached a plateau after about 26 days when starting with 22-day old cultures. Photosynthesis and respiration were determined in a range between 15 °C and 40 °C in defined Micrasterias cell cultures of about this age (cultivation temperature 15 °C, 20 °C or 25 °C). Both processes rose steadily with increasing temperature starting with 15 °C and reached peaks between 30 °C and 32 °C, followed by a considerable drop when increasing the incubation temperature up to 40 °C. The experiments reveal that primary processes of energy formation and consumption are much less affected by temperature influences than cell shape formation and division rate
Non-Enzymatic RNA Hydrolysis Promoted by the Combined Catalytic Activity of Buffers and Magnesium Ions
Authors: AbouHaidar Mounir G. , Ivanov Ivan G.
Published: February 2015

Although Mg2+ is an important cofactor for the specific degradation of RNA by ribozymes, it is not considered as a typical chemical nuclease. In this study we show that in combination with common buffers such as tris(hydroxymethyl)aminomethane and sodium borate. Mg2+ is a powerful catalyst for the degradation of RNA. pH and temperature are found to be the principal factors for the efficient degradation of RNA. Whereas in Tris-HCl/Mg2+ the effi­cient cleavage starts at pH values higher than 7.5 and temperatures higher than 37 °C, in sodium borate RNA degradation begins at pH 7.0 and at 37 °C. RNA hydrolysis promoted under the combined catalytic activity of buffer/Mg2+ results in partially degraded RNA and negligible amounts of acid-soluble material. Reaction is insensitive to the concentration of monovalent cations but is completely prevented by chelating agents (EDTA and citrate) at concentrations exceeding that of Mg2+. Borate-magnesium reaction is inhibited also by some polyvalent alcohols (glycerol) and sugars.
The Thermoluminescence 'Afterglow' Band as a Sensitive Indicator of Abiotic Stresses in Plants
Authors: Janda Tibor , Szalai Gabriella , Giauffret Catherine , Páldi Emil , Ducruet Jean-Marc
Published: February 2015

Single turn-over xenon flashes induce a thermoluminescence (TL) B-band centred near 35 °C. The far-red illumination of leaves at non-freezing temperatures induces a band peaking at around 45 °C (afterglow or AG-band), together with a downshifted B-band peaking between 15 °C and 28 °C. In control, unfrozen wheat plants, the Tmax of the B-band induced after 30 s far-red light at 0 °C was approx. 15-18 °C. In maize plants grown under the same conditions, this far-red-induced downshift was not so strong, since the B-band peaked at 28 - 30 °C. Both a decline in the AG-band and a reversal of the downshift of the B-band were observed after short-term freezing in several plant species. There was usually a sudden drop in the AG-band below a critical freezing temperature. However, while in wheat plants a weak TL emission could be seen between 40-50 °C in frozen samples, in cold-sensitive maize plants this was completely suppressed and only the B-band could be detected. In cold-hardened wheat plants the temperature at which the AG-band was suppressed was lower than in non-hardened plants. Drought and short-term heat stress also affect the AG-band. As the AG-band was found to be more sensitive to several types of stresses than the B-band, it can be used as a sensitive stress indicator. However, the behaviour of the AG-band depends on several factors (for example the age of the leaf, etc.), which must be controlled if different species or varieties are to be compared
Short-Term Responses of Photosystem II to Heat Stress in Cold-Acclimated Atrazine-Resistant and Susceptible Biotypes of Erigeron canadensis (L.)
Authors: Dulai Sándor , Molnár István , Péli Evelin , Lehoczki Endre
Published: February 2015

When leaves of atrazine-resistant (AR) and atrazine-sensitive (S) Erigeron canadensis (L.) plants grown at 5 °C were exposed to an elevated temperature (35 °C) for 30 min, the critical (Tc) and peak temperatures (Tp) of the F0 vs. T curves were considerably higher for the leaves of the S biotype, but not for those of the AR biotype. The temperature dependences of Fv/Fm and ΔF/Fm′ were not greatly different for the heat-treated cold-acclimated AR biotype, in contrast with the situation for the S plants. This short-term heat treatment resulted in a more significant shift in the optimal thermal interval of CO2 fixation for the S than for the AR biotypes
Comparative Study on Gas Exchange, Water Relations and Leaf Anatomy of Two Olive Cultivars Grown under Well-Irrigated and Drought Conditions
Authors: Chartzoulakis Konstantinos , Patakas Angelos , Bosabalidis Artemis
Published: February 2015

The effect of water stress on gas exchange, water relations and leaf anatomical characteristics have been studied in two olive cultivars (Olea europea, L. cv. ‘Koroneiki’ and cv. ‚Mastoidis’). Photosynthetic rate as well as stomatal conductance were decreased in stressed plants. Osmotic potential (π) declined rapidly in stressed plants indicating their ability for osmoregulation. Bulk modulus of elasticity (ε) was significantly higher in stressed compared to well irrigated plants. The volume fraction of intercellular spaces of the upper palisade parenchyma, the spongy parenchyma as well as the lower palisade parenchyma were significantly lower in stressed compared to well irrigated plants. On the other hand, the density of mesophyll cells in the upper palisade parenchyma, spongy parenchyma and lower palisade parenchyma increased significantly in stressed plants
Gas Exchange of Irrigated and Non-Irrigated Pinus canariensis Seedlings Growing Outdoors in La Laguna, Canary Islands, Spain
Authors: Morales Domingo , Peters Juliane , Jiménez M. Soledad , Tausz Michael , Wonisch Astrid , Grill Dieter
Published: February 2015

Chlorophyll fluorescence, gas exchange, water potential and relative water content were measured in the needles of five year old seedlings of Pinus canariensis in order to know their response to mild water stress. Two trial plots of ten plants per plot, of similar age and characteristics were irrigated daily until the experiment was undertaken, then one of the plots was left without watering while the other one was irrigated as before. After a week of treatment, the water potential at midday did not change in any of the irrigated or non-irrigated plants maintaining around -0 .4 MPa, and the relative water content changed from 93% in irrigated to 84% in non-irrigated seedlings. The stomatal conductance decreased 60% in non irrigated plants and as a result CO2 assimilation decreased by 50% and transpiration was reduced at a higher proportion (70% ), indicating a good control against water loss, before any change in water status in the needles could be observed suggesting an isohydric water economy in this plant
Effect of Dehydration on the Photosynthetic Apparatus of Sun and Shade Leaves of Laurel Forest Trees
Authors: Jiménez M. Soledad , González-Rodríguez Agueda , Morales Domingo
Published: February 2015

In this work we study the effect of reduction in relative water content (RW C) on the chlorophyll fluorescence induction kinetics as well as on the membrane integrity, measured as electrolyte leakage, in sun and shade leaves of three Canarian laurel forest trees. No differences were found among the species and type of leaves, when the slow fluorescence kinetic parameters and electrolyte leakage were analyzed, values deviated from the normal ones at 70% and 40% RWC respectively. On the contrary, the photochemical efficiency of PSII was affected at higher values of RWC in sun leaves (90% and 52% RWC depending on the species) than in shade ones (40% RWC). These results indicate that the susceptibility of PSII to water deficit is different depending on species and environmental conditions where the leaves develop
Cadmium against Higher Plant Photosynthesis -a Variety of Effects and Where Do They Possibly Come From?
Authors: Krupa Zbigniew
Published: February 2015

The complexity of in vivo toxic effects of Cd on higher plants makes almost impossible an accurate distinction between direct and indirect mechanisms of its action on the photosynthetic apparatus. We, therefore, postulate that multiple Cd effects on plant physiological and metabolic processes may finally be focused on photosynthesis. This would also explain the phenomenon that only a small fraction of Cd entering chloroplasts may cause such disastrous changes in their structure and function. In return, the inhibition of photosynthesis affects numerous metabolic pathways dependent on the primary carbon metabolism
Effects of Heavy Metals on the Fast Chlorophyll Fluorescence Induction Kinetics of Photosystem II: a Comparative Study
Authors: Ciscato M. , Vangronsveld J. , Valcke R.
Published: February 2015

The effects of toxic concentrations of Cu, Zn and Cd on the fast induction kinetics of fluorescence from photosystem(PS)II were investigated in a comparative way. The fast fluorescence transient from primary leaves of metal-treated bean plants was studied. During several days after metal application, the time course of the changes induced by the different metals was monitored. The results evidenced not only a different time course of the changes in fluorescence related parameters for the three metals, but also different effects on the fluorescence induction kinetics, which could possibly be linked to different mechanisms of action of the metals
Relationship between Changes in Ion Content of Leaves and Chlorophyll-Protein Composition in Cucumber under Cd and Pb Stress
Authors: Sárvári Éva , Fodor Ferenc , Cseh Edit , Varga Anita , Záray Gyula , Zolla Lello
Published: February 2015

Hydroponically cultured cucumber plants supplied with 4 μᴍ Fe chelated either with EDTA or citrate and treated with Cd (10 μᴍ) and Pb (10, 50 μᴍ) from their one- or fourleaf stage were grown up to five-week-old age. The decrease in the chlorophyll content was the most pronounced in plants treated with Cd from a younger age, and in the case of Fecitrate. The chlorophyll a/b ratio of Cd stressed plants was also significantly lowered. In later treated plants the accumulation of chlorophyll was inhibited and the chlorophyll a/b ratio decreased only in the vigorously growing young leaves. Pb treatment had only a slight effect on both parameters. The changes in the chlorophyll-protein pattern of thylakoids were strongly related to their chlorophyll content but the response of each complex was different. Cd reduced the amount of chlorophyll containing complexes in the order of photosystem I > light-harvesting complex II > photosystem Il-core, while light-harvesting complex II appeared somewhat more sensitive than photosystem I in Pb treated plants. In accordance, a decline or blue shift of the long wavelength fluorescence emission band of chloroplasts was observed referring to disturbances also in photosystem I antenna assembly. The accumulation of chlorophyll and chlorophyll-proteins did not show close relationship to the heavy metal content of leaves which was the highest in the first of the intensively expanding leaves in the time of the treatment. The extraordinary sensitivity of photosystem I, and the relative stability of photosystem II under Cd treatment were similar to the case found in iron deficient plants. However, the pattern of chlorophyll content of leaf storeys of Cd treated plants rather followed the changes in their Mn content
A Relationship between Carbonic Anhydrase and Rubisco in Response to Moderate Cadmium Stress during Light Activation of Photosynthesis
Authors: Siedlecka Anna , Gardeström Per , Samuelsson Göran , Kleczkowski Leszek A. , Krupa Zbigniew
Published: February 2015

In our previous research, we showed that low Cd concentration increases the effectiveness of the processes leading to activation of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). This stimulation was dependent on carbonic anhydrase (CA) activity and resulted in protecting Rubisco activity against Cd toxicity. The aim of the present paper was to test whether this mechanism has any influence on light activation of photosynthesis during the first 2 h of illumination. Both the “activation mechanism” of plant response to Cd-stress conditions and its full efficiency at low Cd concentration were confirmed. The CA-dependent light activation of Rubisco at low Cd level was correlated with accelerated attaining of the maximum Rubisco activity by these plants. The amount of Rubisco was also Cd- and timedependent and varied from continuous accumulation in control plants till reaching the maximum level within 30 minutes for the high Cd concentration. An increase in CA activity that was found to be parallel to the decrease of the amount of CA suggested activation of the enzyme by low Cd concentration
Oxidative Stress in Cucumber (Cucumis sativus L.) Seedlings Treated with Acifluorfen
Authors: Gupta Illora , Tripathy Baishnab Charan
Published: February 2015

Illumination of acifluorfen-sprayed and 14 h-dark-incubated cucumber seedlings with coolwhite fluorescent light caused overaccumulation of protoporphyrin IX and severe oxidative stress which resulted in seedling death within 72 h. The ratio of variable fluorescence (Fv)/ maximum fluorescence (Fm), a measure of the functional status of PSII, declined by 30% , 58% and 85% after 24 h, 48 h and 72 h respectively. When 24 h-light-treated plants were transferred to dark for 24 h the Fv/Fm ratio was restored to near control levels suggesting a dark recovery from photodynamic damage. The intracellular distribution of protoporphyrin IX that accumulated in the cotyledons of acifluorfen-treated and 1 h-light-exposed plants was 22% within and 78% outside chloroplasts suggesting migration of protoporphyrin IX within one hour of exposure of plants to light. When thylakoid membranes, treated with exogenous protoporphyrin IX, were illuminated there was a reduction in photosystem II activity. Addition of L-histidine, scavenger of singlet oxygen, to illuminated thylakoid+protoporphyrin IX mixture resulted in substantial protection of photosystem II activity suggesting the involvement of singlet oxygen in protoporphyrin IX-mediated photodynamic damage. In illuminated thylakoid+protoporphyrin IX mixture no indication was found for production of superoxide radicals via type I reaction. In cucumber seedlings acifluorfen-induced synthesis of protoporphyrin IX caused severe photodynamic damage mediated by singlet oxygen generated due to type II photosensitization reaction
Ontogenesis-and Biotic Stress-Dependent Variability of Carbohydrate Content in Snap Bean (Phaseolus vulgaris L.)
Authors: Sárdi Éva , Velich István , Hevesi Mária , Klement Zoltán
Published: February 2015

Physiological examination of resistant and susceptible bean genotypes has shown that the concentration and quantitative ratios of carbohydrates measurable in leaf tissues depend on the age of leaves. During the phases of ontogenesis, the glucose and sucrose levels are the lowest in the primary leaves and highest in the youngest upper leaf. There is a continuous increase in the concentration of both carbohydrates from the oldest to the youngest leaves. The glucose/sucrose quantitative ratio decreases with ageing of the leaves until blooming. Our results indicate that the glucose concentration decreases considerably in the susceptible bean leaves after infection with the bean pathogen Pseudomonas savastanoi pv. phaseolicola. It has been proved that the glucose plays an important role in the formation of the bacterial extracellular polysaccharide (EPS) coat. Because there is a positive correlation between the age-dependent bacterial-resistance and the low sugar (especially glucose) content in older leaves of the originally susceptible bean plant, we think that in the old leaves there is not enough glucose for production of the EPS coat. Lacking EPS coat the bacterial and plant cell walls come in direct contact which permits the induction of hypersensitivity response characteristic of resistance
Nitrogen Shortage in a Tomato Crop; Scaling up from Effects on Electron-Transport Rate to Plant Productivity
Authors: Schapendonk Ad H. C. M. , Oijen  , Pot Sander C. , den Boogaard Riki Van , Harbinson Jeremy
Published: February 2015

Optimization of nitrogen supply in a tomato plant is stepwise assessed, from chloroplast characteristics to whole crop performance. Experiments are reported in which important key processes are quantified in relation to the nitrogen content of leaves. Interactions of N effects with leaf aging and canopy light distribution are analyzed.

A simulation model that integrates this knowledge is constructed. The results of three nitrogen partitioning scenarios for Rubisco suggest that optimization of the distribution of Rubisco between leaf layers is less important for plant productivity than within-leaf optimization of the photosynthetic apparatus
The New Bishomoflavone Ononin and Its Glucoside from Ononis vaginalis
Authors: Bernhardt Mirko , Shaker Kamel H. , Elgamal M. Hani A. , Seifert Karlheinz
Published: February 2015

The new bishomoflavone ononin and its glucoside have been isolated from Ononis vaginalis. The structures were determined primarily by NMR spectroscopy. The assignment of NMR signals was performed by means of 1H - 1H COSY, HMQC and HMBC experiments.
Carbohydrates Protect Mitochondrial F0F1-ATPase Complex against Thermal Inactivation
Authors: Saad-Nehme Jorge , Silva Jerson L. , Meyer-Fernandes Jose Roberto
Published: February 2015

Organisms and cellular systems are required to adapt to stress conditions like high temperature, often responding by accumulating organic solutes, such as sugars. This accumulation is associated with the effectiveness of these osmolytes in minimizing protein denaturation and membrane damage under stress conditions. In this work, we have studied the effect of sugars on the protection against thermal inactivation of mitochondrial F0F1-ATPase complex, in preparations of submitochondrial particles containing or depleted of inhibitor protein. We observed that after 15 min of pre-incubation at 70 °C of latent MgATP-submitochondrial particles (with inhibitor protein) in the presence of 1.5 м of sucrose or trehalose, or 3.0 ᴍ of glucose or fructose, about 80% of enzyme activity remained active. In the same conditions, but in the absence of sugars, the activity of the particles was completely abolished. Submitochondrial particles depleted of the inhibitor protein (AS-particles) were almost completely inactivated after 3 min of pre-incubation at 70 °C in the absence of sugars and more than 60% of the enzyme activity remained active when these particles were pre-incubated in the presence of sugars. In such condition, the enzyme acquires a more compact and heat-stable conformation. Sugars, as well as the inhibitor protein, inhibit reversibly F0F1-ATPase complex activity and protect this enzyme against inactivation by high temperature. Interestingly, the protection, promoted by sugars, of particles containing inhibitor protein is higher than of particles depleted of inhibitor protein, suggesting a synergism between sugar and inhibitor protein.
Preparative Isolation of Anthraquinones from the Fungus Dermocybe sanguined Using Enzymatic Hydrolysis by the Endogenous β-Glucosidase
Authors: Hynninen Paavo H. , Räisänen Riikka , Elovaara Pia , Nokelainen Eila
Published: February 2015

A new and simple enzymatic method was developed for preparative isolation of anthraquinone pigments from Dermocybe sanguined. The endogenous β-glucosidase of the fungus was used to catalyze the hydrolysis of the O-glycosyl linkage in emodin- and dermocybin-1-β-ᴅ-glucopyranosides. The developed enzymatic method was found to be effective for the pigment isolation, as the hydrolysis occurred virtually completely, thus leading to a high pigment yield. Two fractions were obtained by the method: Fraction 1 (94% of the total pigment amount), containing almost exclusively the main pigments emodin and dermocybin, and Fraction 2 (6% ), containing the anthraquinone carboxylic acids. A 10.5 kg amount of fresh fungi yielded 56 g of Fraction 1 and 3.3 g of Fraction 2 anthraquinones. The anthraquinones in each fraction were separated by thin-layer chromatography using toluene-ethyl acetateethanol- formic acid (10:8:1:2, v/v/v/v) as eluent. The components on the chromatograms were detected and characterized by measurements on a densitometer-spectrophotometer. Combined gas chromatography-mass spectrometry was applied to determine the anthraquinone derivatives of Fraction 1 after methylation and acetylation.
Purification, Characterization and Thermostability of Ribulose 1,5-Bisphosphate Carboxylase-Oxygenase from Barley Leaves
Authors: Dolashka-Angelova Pavlina , Ali Syed Abid , Demirevska-Kepova Klimentina , Stoeva Stanka , Voelter Wolfgang
Published: February 2015

The enzyme ribulose-1,5-bisphosphate carboxylase-oxygenase (rubisco) and its functional subunits from barley (Hordeum vulgare L.) leaves were purified to homogeneity by activitydirected sequencial steps of chromatography. Based on the molecular mass estimation by SDS-PAGE, the large subunit (LS) had an apparent molecular weight of ca. 55 kDa, whereas the small subunit (SS) was ca. a 14 kDa polypeptide chain. The N-terminal sequences, established by automated Edman degradation analysis of the purified subunits, showed very close sequence homologies (52-92%) with the subunits of other rubisco enzymes reported from several photosynthetic species. In order to establish the chemical heterogeneity in the rubisco from barley, the amino acid composition of purified native enzyme was analyzed and the results systematically compared with other known type-I rubisco enzymes from spinach, maize, tobacco and pea. Major differences have been observed in the amino acid composition of barley rubisco, the concentration of cysteine, serine, threonine, isoleucine, leucine, arginine and tryptophan residues were found quite variable as compared to other higher plants. The thermostability of the native rubisco was also investigated using circular dichroism and fluorescence spectroscopy. The critical ( Tc) and melting ( Tm) temperatures were determined to be 60 °C and 57 °C, respectively, and at this temperature the enzyme not only retains its structural integrity but also its enzymatic activity. Results of these studies were discussed in the light of structural and functional adaptation of this bifunctional enzvme in C3 and C4 plants to their environments.
Effects of Static Magnetic Field on the Ultradian Lateral Leaflet Movement Rhythm in Desmodium gyrans
Authors: Sharma Vijay Kumar , Engelmann Wolfgang , Johnsson Anders
Published: February 2015

The rhythmic leaflet movements of the plant Desmodium gyrans (L.f.) DC slow down in the presence of a static magnetic field. The leaflet positions were digitally retrieved from sequential CCD camera images of the moving leaflets. The experiments were performed under constant light (ca. 500 lux) and temperature (about 20 °C) conditions. The period of the leaflet was then around 5 min. Leaflets moving up and down in a magnetic field of approximately 50 mT flux density increased the period by about 10% due to a slower motion in the “up” position. Since during this position a rapid change of the extracellular potentials of the pulvinus occurs, it is proposed that the effects are mediated via the electric processes in the pulvinus tissue.
Fatty Acid Profiles of Main Lipid Classes in Adult Chrysomela vigintipunctata (Scopoli) (Coleopterai:Chrysomelidae)
Authors: Nikolova Nelly , Rezanka Tomas , Nikolova-Damyanova Boryana
Published: February 2015

The fatty acid composition of the willow leaf beetle Chrysomela vigintipunctata (Scopoli) (Coleoptera: Chrysomelidae) is presented in this paper. Fatty acids in the total lipid extract, triacylglycerols, free fatty acids and polar lipids were compared. One hundred and fifteen fatty acids were identified in the total lipids. The mixture comprised compounds with normal and branched-chains of 12-30 carbon atoms and zero to six double bonds in different positions in the carbon chain. Substantial amounts of unsaturated eicosanoic fatty acids known as important precursor of eicosanoids in insects were detected in the lipids as were biologically significant positionally isomeric dienes, trienes and tetraenes of the series (n-3) and (n-6) of C16, C18, and C22 fatty acids. Also present was a mixture of hydroxy-FA. Triacylglycerols contained mostly saturated and monounsaturated fatty acids. Polyunsaturated fatty acids were found mostly in free fatty acids and especially in polar lipids.
New Spirorotenoids from Tephrosia candida
Authors: Andrei Cesar C. , Vieira Paulo C. , Fernandes João B. , Silva M. Fátima das G. F. da , Fo. Edson Rodrigues
Published: February 2015

The ethyl acetate extract of roots of Tephrosia candida afforded three new spirorotenoids belonging to a new class of spirocompounds, named tephrospirolactone, tephrospiroketone I, and tephrospiroketone II. The structures of these compounds were determined mainly based on spectral analysis. The only known spirorotenoid described in the literature is amorphispironone, isolated from Amorpha fruticosa.
Extracellular Polysaccharides of Penicillium vermiculatum
Authors: Kogan Grigorij , Matulová Mária , Michalková Eva
Published: February 2015

Extracellular polysaccharide mixture that forms a viscous mucilate in the fermentation medium during industrial cultivation of Penicillium vermiculatum was isolated by ethanol precipitation and its structural characteristics were investigated by a combination of physicochemical methods. The mixture contained two structurally different polysaccharides similar to those previously described for some fungal species. This is the first report of the fully structurally characterized extracellular polysaccharides of Penicillium vermiculatum.
Trichosetin, a Novel Tetramic Acid Antibiotic Produced in Dual Culture of Trichoderma harzianum and Catharanthus roseus Callus
Authors: Marfori Eufrocinio C. , Kajiyama Shin’ichiro , Fukusaki Ei-ichiro , Kobayashi Akio
Published: February 2015

The dual culture of Trichoderma harzianum and Catharanthus roseus callus produced an antimicrobial compound with a remarkable activity against the Gram-positive bacteria Staphylococcus aureus and Bacillus subtilis. Structural elucidation revealed that this compound, which we have named trichosetin, is a novel tetramic acid (2,4-pyrrolidinedione) antibiotic and a homolog of the fungal metabolite equisetin. This compound however, was not produced in the individual culture of T. harzianum or C. roseus callus.
Antifungal Activity of the Essential Oils from Some Species of the Genus Pinus
Authors: Krauze-Baranowska Mirosława , Mardarowicz Marek , Wiwart Marian , Pobłocka Loretta , Dynowska Maria
Published: February 2015

The chemical composition of the essential oils from the needles of Pinus ponderosa (north american pine), P. resinosa (red pine) and P. strobus (eastern white pine) has been determined by GC/MS (FID). The essential oils from P. resinosa and P. ponderosa in comparison to P. strobus have been characterized by the higher content of β-pinene (42.4%, 45.7% and 7.9% respectively). On the other hand, α-pinene (17.7%) and germacrene D (12.2%) were dominant compounds of P. strobus. Moreover the essential oil from P. resinosa was more rich in myrcene-15.9%. Estragole and Δ-3-carene, each one in amount ca 8% were identified only in P. ponderosa. The content of essential oils in the needles slightly varied - 0.65% - P. resinosa, 0.4% - P. strobus, 0.3% - P. ponderosa. The antifungal activity has been investigated towards Fusarium culmorum, F. solani and F. poae. The strongest activity was observed for the essential oil from P. ponderosa, which fully inhibited the growth of fungi at the following concentrations - F. culmorum, F. solani at 2% and F. poae at 5%.
Microbial Transformation of a Mixture of Argentatin A and Incanilin
Authors: Maatooq Galal T. , Hoffmann Joseph J.
Published: February 2015

The biotransformation of a mixture of argentatin A (20%) 1 and incanilin (80%) 2 by Gibberella suabinetti ATCC 20193 and Septomyxa affinis ATCC 6737 demonstrated the conversion of incanilin to 16β-hydroxylanosta-2, 8, 23-triene, while argentatin A did not react. The acetate of this triterpenoid mixture was biotransformed by Septomyxa affinis ATCC 6737 to give five metabolites. Argentatin A acetate was transformed to 3β, 16β,30-trihydroxycycloart- 20, 24-diene, 20R, 24R-epoxy-16β, 25-dihydroxy-3, 4-seco-cycloart-4(28)-en-3-oic acid acetate and 20R, 24R-epoxy-16β, 25-dihydroxy-3, 4-seco-cycloart-4(28)-en-3-oic acid. Incanilin acetate was converted to 16β-hydroxylanosta-2, 8, 23-triene and 20R, 24R-epoxy-16β, 25-dihydroxy-3, 4-seco-lanost-1, 4(28), 8-trien-3-oic acid acetate. The structural elucidations of these metabolites were achieved by different spectroscopic methods.
Photo-Induced Decomposition of 2-Chloroaniline in Aqueous Solution
Authors: Winarno Ermin Katrin , Getoff Nikola
Published: February 2015

A study was performed on the oxidizing degradation of 2-chloroaniline (used as a model pollutant in water) by photolysis (λ = 254 nm). The change of spectrum and substrate concentration of treated solutions was measured spectrophotometrically as well as by HPLC. The yields of the degradation products (chloride ions, ammonium ions, formaldehyde, etc.) were studied as a function of UV-dose. Their initial quantumyields (Qi) were determined by specific analysis. It was shown that the substrate photolysis in the presence of N2O is most efficient, followed by degradation in media saturated with pure oxygen and air. A probable reaction mechanism for the photo-induced degradation of 2-ClA is presented.
Composition of Lipophylic Extracts from Two Tunicates, Styela sp. and Phallusia sp. from the Eastern Mediterranean
Authors: Slantchev Krasimir , Yalçın Funda , Ersöz Tayfun , Nechev Jordan , Çalış İhsan , Stefanov Kamen , Popov Simeon
Published: February 2015

Sterols, volatiles and lipids were isolated and identified from lipophylic extracts from two tunicates, Styela sp. and Phallusia sp., occurring in the Eastern Mediterranean. Seventeen sterols were identified. The sterol composition of the two organisms appeared to be similar except for the concentrations of 5α-stanols. Both tunicates were characterized by the presence of sterols with a (22Z)-double bond. In the volatiles significant amounts of chlorinated compounds were found (phenols in Styela sp. and hydrocarbons in Phallusia sp.). The fatty acid composition of triacylglycerols and phospholipids of the two tunicates showed significant differences.
Draculone, a New Anthraquinone Pigment from the Tropical Lichen Melanotheca cruenta
Authors: Mathey Annick , Spiteller Peter , Steglich Wolfgang
Published: February 2015

A new red anthraquinone, draculone, has been isolated from the corticolous tropical lichen Melanotheca cruenta (= Trypethelium cruentum = Pyrenula cruenta) together with minor quantities of the known anthraquinone pigment haematommone. The structure of draculone was determined as 2-acetyl-1,3,4,6,8-pentahydroxyanthraquinone by spectroscopic methods.
Sesquiterpene Lactones from Achillea collina Becker
Authors: Mustakerova Elena , Todorova Milka , Tsankova Elena
Published: February 2015

Aerial parts of Achillea collina afforded, in addition to five known sesquiterpene lactones two new germacranolides and one new eudesmanolide, the structures of which were elucidated by spectroscopic methods.
Oleanane Triterpenoids from Cedrela montana (Meliaceae)
Authors: Castellano Leonardo , de Correa Rosabel S. , Martínez Eduardo , Calderon Jose´ S.
Published: February 2015

Two new oleanane-type triterpenes, characterized as 3-oxo-11α,12α-epoxy-oleanan-28,13β- olide and 3-oxo-olean-11-en-28,13β-olide , were isolated from the fruits and seeds of Cedrela montana (Meliaceae). In addition, the known compounds oleanonic acid , a mixture of β-sitosterol and stigmasterol, and the limonoid photogedunin were also isolated. The structures of the new compounds were established by spectroscopic methods, including 2D NMR.