bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biosynthesis of Porphyrinogens in Etiolated Euglena gracilis Z. I. Isolation and Purification of an Endogenous Factor Stimulating the Formation of Porphyrinogens
Authors: Juknat A. A. , Dörnemann D. , Senger H. 
Published: August 2018

A low molecular weight, heat-stable factor has been purified from Euglena gracilis supernatant fraction by employing gel filtration, cation and anion exchange and paper chromatography.
This endogenous compound stimulates porphobilinogenase (PBG-ase) (EC 4.3.1.8) activity, an enzyme of the porphyrin biosynthetic pathway.
10-7 ᴍ folic acid and 10-4 ᴍ 6-biopterin produced a significant activation, equivalent to 2-4 units of the purified factor.
Elution patterns from the columns and fluorescence and UV absorption peaks suggest that this compound is a pteridine. This conclusion is further supported by the fact that both, folic acid and 6-biopterin can replace the action of the isolated factor on PBG-ase. The mechanism of stimulation is discussed.
Synthesis of Flavonoid Sulfates. II. The Use of Aryl Sulfatase in the Synthesis of Flavonol-3-sulfates
Authors: Barron Denis , Ibrahim Ragai K. 
Published: August 2018

Abstract
The rates of aryl sulfatase hydrolysis of several 7-, 4′- and 3-sulfated flavonoids were compared and found to follow the order 7 or 4′ >>> 3. The complete resistance of the 3-sulfate ester to enzyme hydrolysis provided a unique and convenient method for the synthesis of a number of naturally occurring flavonol-3-sulfates from the corresponding higher sulfated analogs in quantitative yield.
Mammalian Pheromone Studies, VII*. Identification of Thiazole Derivatives in the Preorbital Gland Secretions of the Grey Duiker, Sylvicapra grimmia, and the Red Duiker, Cephalophus natalensis
Authors: Burger B. V. , Pretorius P. J. , Stander Jonine , Grierson G. R. 
Published: August 2018

Abstract
2-Isobutyl-1 ,3-thiazole and its 4,5-dihydro derivative were identified in the preorbital gland secretions of the grey duiker, Sylvicapra grimmia, and the red duiker, Cephalophus natalensis, but are absent from the preorbital secretion of the blue duiker, C. monticola. These two compounds which are present in high, but varying concentrations in the secretions of male grey duikers, are present in low concentrations in the secretions of females. This seems to be the only consistent significant difference between the secretions of male and female grey duikers and together with the fact that only males mark out their territories, was construed as evidence in favour of these two compounds playing a significant role in the territorial behaviour of male grey duikers.
Effect of Preparative Procedures on Ghostcells from Bovine Erythrocytes
Authors: Pitterich Horst , Lawaczeck Rüdiger 
Published: August 2018

Abstract
Several methods for the preparation of “white ghosts” or “resealed ghosts” were described in the recent literature. This article compares three methods to prepare white, resealed ghosts from bovine erythrocytes based on the principle of hypotonic lysis. The methods described differ by the removal of hemoglobin from the empty cells. The main difference between the standard centrifugation, the gelfiltration and the hollow-fibre diafiltration is the mechanical stress on the leaky membranes after swelling in hypotonic media. Mean cellular volumes, rates of potassium-efflux and the access of impermeable dyes to cytoplasmatic proteins are criteria to differentiate between ghostcell-populations.
Sex Pheromone of Brinjal Shoot and Pod Borer Leucinodis orbonalis Guenèe (Lepidoptera: Pyralidae: Pyraustinae)
Authors: Attygalle Athula B. , Schwarz Jürgen , Gunawardena Neelakanthi E. 
Published: August 2018

Abstract
(E)-11-Hexadecenyl acetate is the major volatile component of the sex pheromone gland of female Leucinodis orbonalis collected from Sri Lanka. (E)-11-hexadecen-1-ol was also found in trace quantities.
Evidence of an Intracellular Dissipative Structure
Authors: Medina Miguel Angel , Núñez de Castro Ignacio 
Published: August 2018

Abstract
Data are presented showing the result of the functioning of the mitochondrial respiratory chain in Ehrlich ascites tumour cells incubated with glucose and glutamine.
The very different results obtained depending on the order of substrate addition suggest that the functioning of the respiratory chain in Ehrlich cells far-from-equilibrium maintains an intracellular dissipative structure.
Biosynthesis of Cytochalasans. XI. New Results on the Incorporation of Phenylalanine into Cytochalasin D by Zygosporium masonii [1]
Authors: Hädener Alfons , Roth Patricia , Tamm Christoph 
Published: August 2018

Abstract
Incorporation of L-[2-2H]phenyl-[2-2H]alanine and L-phenyl-[2-13C, 15N]alanine into cytochalasin D by Zygosporium masonii involved the complete loss of both the α-2H- and the α-15N-atom. Incorporation of a mixture of L-phenyl-[15N]alanine and L-[U-14C]phenylalanine into cytochalasin D and protein amino acids (phenylalanine, leucine, isoleucine) was accompanied by a substantial loss of 15N with respect to 14C. These effects are attributed to rapid exchange reactions taking place while L-phenylalanine is part of the intracellular pool of amino acids. In addition, the medium- and concentration-dependent incorporation of the carbon skeleton of exogeneous D-phenylalanine into cytochalasin D is reported. In a peptone-based complex medium, D-phenylalanine is poorly incorporated. Throughout the whole concentration range (0-250 mg/l), the incorporation rates are less than 10% of those of L-phenylalanine. In a minimal medium containing NH4NO3 as nitrogen source however, D-phenylalanine is preferred over the natural enantiomer by a factor of 1.28 up to 6.78, depending on the concentrations of exogeneous D - and L-phenylalanine. These effects are attributed to the medium-dependent activities of different amino acid transport systems responsible for the uptake of D - and L-phenylalanine in Z. masonii.
Inhibitors Influencing Plant Enzymes of the Polyamine Biosynthetic Pathway
Authors: Christ Marbeth , Felix Hansruedi , Harr Jost 
Published: August 2018

Absract
Several enzymes involved in polyamine biosynthesis namely ornithine, arginine and S-adenosylmethionine decarboxylase as well as spermidine synthase, were analyzed in partially purified wheat extracts. For all enzymes effective inhibitors were found. Among them the most interesting was l-aminooxy-3-aminopropane, which inhibited all three decarboxylases. Classical polyamine biosynthesis inhibitors like difluoromethylornithine, difluoromethylarginine. methyl glyoxal bis- (guanylhydrazone) and cyclohexylamine were also inhibitory on plant enzymes.
A remarkable difference in the amount of arginine and ornithine decarboxylase existed in wheat. Arginine decarboxylase seems to be more important at least during the early stage of development. Influence of polyamine synthesis inhibitors on polyamine levels is more likely to come from arginine decarboxylase inhibitors.
As inhibitors of all essential enzymes involved in plant polyamine biosynthesis were found, the study of the importance of polyamines in plant physiology will be considerably facilitated.
Product Specificity in an Entire Series of (ω-6 Z, ω-9 Z)-C13~C20-Dienoic Acids and -Dienols for Soybean Lipoxygenase
Authors: Hatanaka Akikazu , Kajiwara Tadahiko , Matsui Kenji , Yamaguchi Masanori 
Published: August 2018

Abstract
Substrate specificity of soybean lipoxygenase-1 (EC 1.13.11.12) was studied using as synthetic substrate analogs an entire series of (ω-6 Z,ω-9 Z)-C13 ~ C20 (rdienoic acids and (ω-6 Z,ω-9 Z)- C12 ~ C20 (i-dienols. The relative activity of lipoxygenase-1 against linoleic acid (C18:2COOH) was the highest among the dienoic acids and that of (6Z.9Z)-pentadecadienol (C15:2OH) was the highest among the dienols. Soybean lipoxygenase-1 oxygenated almost at to- 6 position of the dienoic acids independently of the chain length. With the dienols as substrate, the position of oxygenation was much influenced by the chain length. Above all, C15:2OH was selectively oxygenated at ω-10 rather than at ω-6 . Kinetic analyses revealed that longer and more hydrophobic dienols had higher affinity but lower velocity of oxygenation reaction. But higher velocity was obtained when smaller Km value was observed for the dienoic acids.
To clucidate stereospecificity of the oxygenation to C15:2OH, optically active authentic samples were prepared via biological asymmetric reduction with baker’s yeast. The ω- 6 oxygenation to C15:2OH was found to be (S)-specific (R/S = 26/74) as is that to C18:2COOH. whereas the ω-10 oxygenation showed low enantioselectivity (R/S - 60/40).
Trace Elements in Propolis and in its Ethanolic Extract (EEP) as Determined by Neutron Activation Analysis
Authors: Scheller S. , Czauderna M. , Krol W. , Konecki J. , Czuba Z. , Gabrys J. , Glowacka M. , Shani J. 
Published: August 2018

Abstract
Propolis is a natural composite balsam, manufactured by honey bees, and active biochemically. Some of its biological effects are attributed to its ability to stimulate enzymatic systems, which in many instances involve trace elements. In the present study we assayed propolis and its ethanolic extract (EEP) for trace elements, and quantified them with the aid of neutron activation analysis. Four elements that have been detected in propolis and EEP for the first time are Na. Cr, Co (ppm) and Ag (ppb). The wide concentration range of the inorganic components in various batches of propolis and EEP is due to the difference in their extraction capacities, and to the variability in the environmental pollutants and the flora at the beehive sites.
Kaurane-Type Diterpenes from Fern Frond Exudates
Authors: Rüedi Peter , Wollenweber Eckhard , Marx Dieter , Scheele Cornelia 
Published: August 2018

Abstract
The viscid exudate found on fronds of the fern, Cheilanthes kaulfussii, consists of terpenoids in which flavonoid aglycones are dissolved. One of the terpenes is shown to be em-kaur-16-en-19-oic acid. The farinose frond exudate of Notholaena pallens contains this acid as the major constituent and its 3 R-hydroxy derivative, together with flavonoid aglycones as minor components. In N.incana, two of the diterpenes that form the farinose exudate along with flavonoid aglycones have been identified as 16R-ent-kauran-17-oic acid and 16R,17-dihydroxy-3-oxo-ent-kaurane (abbeo-kutone).
Isoflavonoids from the Root Bark of Piscidia erythrina and a Note on the Structure of Piscidone
Authors: Ingham John L. , Tahara Satoshi , Shibaki Seiji , Mizutani Junya 
Published: August 2018

Abstract
A methanolic extract of Piscidia erythrina root bark has been found to contain various isofla-vonoids including rotenone (rotenoid), lisetin (coum aronochrom one) and six known isoflavones (ichthynone, piscidone, piscerythrone, 2′-deoxypiscerythrone, 6′-prenylpiscerythrone and 3′,5′-diprenylgenistein). The extract additionally yielded three new 5-hydroxyisoflavones (piscery-thrinetin, 2′-hydroxypiscerythrinetin and isow ighteone) and a previously unreported coum arono­ chrom one (8-prenyl-lisetin). All four com pounds were identified using a com bination of spectro­ scopic (UV , MS, 1H NMR) and chemical methods. Although several other 5-hydroxyisoflavones were also isolated from the root bark extract, the quantities of each were sufficient only to permit their partial characterization. Structure 2 for piscidone has been confirmed by 1H NMR spectros­ copy.
The Occurrence of β-Carotene-5,6-epoxide in the Photosynthetic Apparatus of Higher Plants
Authors: Young Andrew , Barry Paul , Britton George 
Published: August 2018

Abstract
The occurrence of β-carotene-5,6-epoxide in higher plant photosynthetic tissue is described. The compound is found in isolated chloroplasts, thylakoids and other subchloroplast particles but can only be detected in intact leaves or cotyledons of higher plants when these are exposed to very high light intensities or to inhibitors such as monuron or paraquat. The distribution of the epoxide within the individual pigment-protein complexes is given. It is particularly associated with the PS I reaction centres (C P I and CP la) and less so with the PS II reaction centre (CPa).
Circular dichroism shows that the β-carotene-5,6-epoxide isolated from photosynthetic tissue is optically inactive. It is therefore not produced enzymically but is a product of photooxidative events in the photosynthetic apparatus. Its presence in photosynthetic tissue is a reliable indicator of photooxidative damage to the thylakoid membrane involving oxidation of β-carotene.
Growth Inhibition of Kirkman-Robbins Hepatoma by l-(l,3-Dihydroxy-2-propoxymethyl)-5,6-tetramethyIeneuraciI and Possible Mechanism of its Biological Activity
Authors: Greger Janusz , Dramiriski Marcin 
Published: August 2018

Abstract
Hepatoma, Acyclonucleoside Metabolism , dN and dTMP Kinases. dNTP Pool l-(l,3-D ihydroxy-2-propoxym ethyl)-5,6-tetram ethylene-uracil (DHPTU) is a newly synthe­ sized acyclonucleoside which shows cytostatic properties. It was tested in Syrian hamster 6 days after heterotransplantation of Kirkm an-Robbins hepatoma. A reduction of tumour weight by 61% was found 48 h after its intraperitoneal (i.p .) administration in doses of 20 mg per kg of body weight. Inhibition of tumour growth is accompanied by a reduction of dThd, dGuo and dTMP kinase activities in tumourcytosol (by 91% and 74% and 55% , respectively) and decrease in contents of dTTP, dGTP and dA TP (by 92% , 77% and 67% , respectively) in dNTP pool. DHPTU is not phosphorylated by any tumour dN kinases, but undergoes cleavage with TU release in reaction catalyzed by the tumour cell enzyme, com petitively inhibited by FA . After [14C]DHPTU or [14C]TU had been given i.p. to the animals with the tumour, 90% of the subcellu­lar fraction labelling fell into the nuclear fraction. How ever, if [l4C ]DHPTU was administered with FA and DCF, 27% of radioisotope was found in the nuclear fractions and 68% in cytosol. Since D C F which prevented FA deamination to FB (which is not an inhibitor of the mentioned enzyme) reduces DHPTU-induced changes in activity of dN kinases and dTMP kinase in hepato­ ma cells, the cytostatic activity of DHPTU seems to be connected to an enzyme which releases TU from DHPTU .
The Compositions of the Essential Root Oils from Pimpinella saxifraga s.l. and Chemotaxonomic Implications
Authors: Kubeczka K.-H. , Bohn I. , Schultze W. 
Published: August 2018

Abstract
The essential root oils of the Pim pinella saxifraga subspecies eusaxifraga, alpestris and nigra were investigated by means of capillary GC and spectroscopic m ethods. A total of 48 com ponents was identified.
Characteristic constituents of all oils are pseudoisoeugenol derivatives, sesquiterpenoids and trinor-sesquiterpene hydrocarbons, but the qualitative and quantitative patterns of the individual oils exhibit significant differences.
The results obtained were discussed in regard to a chemotaxonomic reliable delimitation of the 3 described subspecies of Pimpinella saxifraga L.
Low Concentrations of Phytoalexins Correlate with Resistance in Regenerated Plants from Meristem Cultures of Vicia faba L
Authors: Thynn M. , Wolff A. , Gorge E. , Werner D. 
Published: August 2018

Abstract
In tissue cultures from shoot apex meristems with leaf primordias of Vicia faba cv. TP667, addition of low concentration of auxins (0.01 mg ・1-1) induced regeneration of whole plants at high frequency (100%). The combination of NAA and kinetin or GA , also induced a high yield of plant regeneration. Regenerated plants from various cultivars on a medium with 2 ,4 D (0.01 mg ・1-1) were infected with Botrytis cinerea, Phytophthora megasperma and R hizoctonia solani. Accumulation of phytoalexins, ethylene production and the resistance to fungal diseases were studied. In general, production of phytoalexins occurred at a high level in all cultivars infected with B. cinerea. Ethylene production varied more in the seven cultivars studied than phytoalexin accumulation. No cultivar was resistant to B. cinerea. The highest resistance and the low est concentration of phytoalexin was found after infection by R. solani, and phytoalexin accumulation and resistance were interm ediate in plants infected by P. megasperma. The data suggest that only low to medium concentrations of phytoalexin in faba beans are correlated with resistance of regenerated plants.
Fluorescence Reaction of Chromatin by Curcumin
Authors: Stockert J. C. , Castillo P. Del , Gómez A. , Llorente A. R. 
Published: August 2018

Abstract
Treatment of cell smears, paraffin, and Epon tissue sec­tions with aqueous solutions of curcumin results in a green fluorescence reaction in chromatin under violet-blue exci­tation which is abolished after extraction procedures with DNase and TCA. The selective fluorescence characteris­ tics of curcumin support the possibility of employing this dye as a new fluorochrome.
Lipid Composition and Structural Studies on Lipids from the Land Snail Eobania vermiculata
Authors: Stavrakakis Helen J. , Mastronicolis Sofia K. 
Published: August 2018

The total lipids of the commercial land snail Eobania vermiculata (Gastropoda, Pulm onata, Stylom m atophora) are found to constitute a small percentage (0.8% ) of the wet tissue, which is comparable to that reported for other gastropods. Polar lipid components comprise 61.4% of the total lipids. The individual lipid classes obtained by column chromatographic fractionation were purified by preparative TLC or by column chromatography and their structure was confirmed by a combination of chromatographic and analytical determinations before and after mild alkaline hydrolysis and/or (dry) acid methanolysis and by IR analysis. Neutral lipids represent 36.4% of total lipids, containing cholesterol, cholesterol esters and triglycerides as their major components (26.2% , 29.1% and 25.5% respectively). They contain also a significant amount (14%) of free glyceryl ethers, which are found in a mollusc for the first time. The overall composition of the polar lipids (mol/100 mol lipid-P) was found as follows: Cardiolipin, 2.9; phosphatidylethanolamine, 24.9 (of which 19.8% plasmalogen analog); phosphatidylcholine, 49.2 (of which 45.6% glycerylether analog); ceramide aminoethylphosphonate, 7.5 plus 0.01 (another three minor species); diglyceride-am noethylphosphonate, 6.3; Sphingoethanolamine 1.65 (for the first time found and structurally studied in a land gastropod); and phosphatidic acid 1.1. Unsaturated fatty acyl groups represent about 72.6 and 44.1 respectively in phosphatidylethanolamine and phosphatidylcholine. A significant amount (70.5% ) of unsaturated fatty acids is concentrated in neutral lipids.
The C16:0 alk-1-enyl chain was found to predominate (55.6% ) in the side chains of ethanolamine plasmalogen. Batyl alcohol was found as the main glycerylether bound to choline phosphate (97.5% ).
Saturated fatty acyl groups with 16 carbon atoms were main components (54%) of the major ceramide aminoethylphosphonate species.
Hormonal Modulation of the Rat Mammary Gland γ-Glutamyltranspeptidase
Authors: Ríos M. , Puente J. 
Published: August 2018

1. The in vivo effect of estradiol and domperidone (a hypophysis stimulator of prolactin secretion) in immature ovariectomized-adrenalectomized and hypophysectomized rat mammary gland was studied.
2. γ-Glutamyltranspeptidase activity was used to evaluate the role of estradiol in the specific response of the gland to prolactin.
3. Our results suggest that the activity of γ-glutamyltranspeptidase, like casein and lactose synthetase, is part of the specific response of the gland to prolactin.
Temperature-Dependent ESR Studies of Radical Pairs in Single Crystals of Barbituric Acid
Authors: Schupfner Robert , Müller Adolf 
Published: August 2018

Abstract
After irradiation of single crystals of barbituric acid with X-rays at 77 K different types of radical pairs are found, which are com posed of only one type of monoradical. The properties of radical pairs of the unpaired electrons are studied using frequency-variable ESR methods at various temperatures. In addition to the radical pairs AD and BC two further pairs A′D′ and XY were identified. Measurements of the fine structure parameter D showed a linear temperature dependence in some regions between 77 K and 290 K. At 240 K the radical pairs AD and A′D′ changed reversibly into A*D* and this pair remained stable up to 290 K.
A level anticrossing effect was observed with the pair AD. The exchange energy J between the singlet state and the triplet state was determined as -(15.1 ± 0.6) GHz at 77 K and its temperature coefficient as -(3.8 ± 0.8) × 10-3K-1.
Synergistic Activity of the Herbicide Safener Dichlormid with Herbicides Affecting Photosynthesis
Authors: Fedtke Carl , Strang Robert H. 
Published: August 2018

Abstract
Dichlormid, a safener for thiolcarbamate herbicides, was tank-mixed with several herbicidal inhibitors of photosystem II, or with the herbicide acifluorfen, and applied postemergence to Ipomoea hederacea plants. Dichlormid had no visible effects on the plants when applied alone, but interacted synergistically with the herbicides in the combination treatments. Dichlormid strongly decreased the ascorbic acid levels in the Ipomoea hederacea cotyledons. Ascorbate is known to protect plant tissue from photooxidative damage. The herbicides which interacted synergistically with dichlormid are believed to generate their phytotoxic action via the production of excess singlet oxygen. It is suggested that the decreased ascorbate levels in the Ipomoea hederacea cotyledons after dichlormid treatment result in an impaired singlet oxygen scavenging system and consequently lead to increased plant damage in the presence of singlet oxygen generating herbicides.
Morphology and Chemical Contents of Dufour Glands of Pseudomyrmex Ants (Hymenoptera: Formicidae)
Authors: Attygalle A. B. , Billen J. P. J. , Jackson B. D. , Morgan E. D. 
Published: August 2018

Abstract
The morphology and ultrastructure of the Dufour gland of a pseudomyrmecine ant is described. The gland has an unusually large volume but possesses a very thin epithelial lining. Its morphology does not constitute a specific subfamily character as in some ant subfamilies. Analysis by gas chromatography-mass spectrometry of the glands of three species showed them all to be rich in saturated linear hydrocarbons (C17:0 and C15:0 dominant) and isopropyl esters of the common fatty acids. Each species produces its own characteristic mixture of these substances. The most abundant ester in Pseudomyrmex ferruginea is isopropyl oleate and in P. sp. A it is isopropyl palmitate, in P.flavicornis there is only a trace of isopropyl palmitate. An alate female of P. ferruginea contained a very similar mixture to that of the workers.
Anzeichen sexueller Fortpflanzung bei dem plasmodialen Protisten Chlorarachnion reptans Geitler / Indications of Sexual Reproduction in the Plasmodial Protist Chlorarachnion reptans Geitler
Authors: Grell Karl G. 
Published: August 2018

Abstract
The algal protists Reticulosphaera socialis Grell and Chlorarachnion reptans Geitler are “meroplasmodia”: They consist of separate cell bodies and a comm on reticulopodial network by means of which they capture and digest food organisms, for instance diatoms. When food becomes exhausted, the meroplasmodium disintegrates sooner or later into single cells.
In Chlorarachnion reptans shortage of food may lead directly to globular resting cells with a distinct cell wall. In other cases disintegration is delayed. The plasmodial cells, still connected by reticulopodial strands, move about and join with single resting cells to form pairs. After pair formation they lose the reticulopodial connections, round off and form a cell wall of their own. The cells which rested from the beginning on start growing, whereas the cells which searched for them do not. It is probable that the nuclei of the latter are transferred into the growing cells so that synkarya are formed. If this the case, pair formation is a fertilization process and the growing cells are zygotes. A single zygote, isolated and transferred on a “lawn” of diatoms, gives rise to a plasmodium whose cells display both sexual types again.