bluuebunny/crossref_metadata_2025 huggingface dataset:
Polybrominated Non-Terpenoid C15 Compounds from Laurencia paniculata and Laurencia obtusa
Authors: Imre Sedat , Aydoğmuş Zeynep , Güner Hüseyin , Lotter Hermann , Wagner Hildebert
Published: August 2018

Two polybrominated C15-acetogenins (1,2) isolated from a Mediterranean sponge previously and a new polybrominated bicyclic ether with a bromoallenic side chain (3) were isolated from Laurencia paniculata and Laurencia obtusa respectively. The structures of these compounds were elucidated by spectroscopic methods.
Chromanones from Lentinus crinitus (Basidiomycetes)
Authors: Abrahanr Wolf-Rainer , Abate Dawit
Published: August 2018

The fungus Lentinus crinitus DR-5 (Basidiomycotina) produces in submerse culture the new natural products 2,2-dimethyl-6-methoxy-4-chromanone 1, its alcohol 3 and (S)-2,2-di-methyl-3-hydroxy-6-methoxy-4-chromanone 2. Beside these merohemiterpenes the antibioti-cally active hirsutane sesquiterpenes 5 -8 were isolated. The formation of these metabolites displayed strong dependence from the carbon source in the medium. While lactose favoured the formation of the antibiotic sesquiterpene ketones 5 and 6, they were suppressed with mannose where the hemiterpenes 1 and 4 and the hirsutane-diol 8 were the dominating metabolites.
Purification and Partial Characterization of the Streptomyces viridochromogenes TÜ494 Phosphinothricin-N-acetyltransferase Mediating Resistance to the Herbicide Phosphinothricin in Transgenic Plants
Authors: Vinnemeier Josef , Dröge-Laser Wolfgang , Pistorius Elfriede K , Broer Inge
Published: August 2018

A purification scheme for the enzyme phosphinothricin-N-acetyltransferase (PAT) originating from Streptomyces viridochromogenes {pat-gene product from Streptomyces virido­chromogenes) and mediating herbicide resistance to transgenic plants was developed. The enzyme was isolated from a transformed and overproducing Escherichia coli strain. With a combination of ammonium sulfate fractionation, chromatography on DEAE-Sephadex A50-, Phenylsepharose-, Hydroxylapatite-and FPLC-Superose 12-columns it was possible to obtain PAT which was at least 90 % homogeneous on the basis of SDS-PAGE. The properties of the isolated PAT were compared with the properties of PAT from S. hygroscopicus (bar-gene product from S. hygroscopicus) previously isolated and characterisized by Botterman, J., Gossele, V., Thoen, C., Lauwereys, M. (1991), Gene 102, 33-37. Differences were observed in the molecular masses of the two native enzymes (PAT from S. viridochrogenes being a dimer of 40 kD and PAT from S. hygroscopicus being a monomer of 21 kD), and in the temperature sensitivity of the two enzymes (the PAT from S. viridochromogenes being slightly more temperature stable than PAT from S. hygroscopicus). However, since the pat and the bar-gene are to 85 % homologous, substantial similarities exist between the two enzymes especially in the kinetic values and the substrate specificity. The isolated S. virido­chromogenes PAT did not acetylate putative substrates present in the plant cell. Antibodies were raised against the isolated protein. This antiserum was able to detect PAT in transgenic plants and therefore is suitable to analyse the fate of the protein in such plants under various stress conditions.
Fungal Melanin Biosynthesis Inhibitors: Introduction of a Test System Based on the Production of Dihydroxynaphthalene (DHN) Melanin in Agar Cultures
Authors: Thines Eckhard , Daußmann Thomas , Sterner Olov , Semar Martin , Anke Heidrun
Published: August 2018

In a screening for inhibitors of fungal melanin biosynthesis a novel test system was success­ fully employed. With this test system, based on the production of dihydroxynaphthalene melanin (DHN melanin) by a Lachnellula species in agar cultures, extracts of cultures of basidiomycetes, ascomycetes and deuteromycetes were tested. From fermentations of Col-lybia dryophila, 6-methylpurine (1) and 6-methyl-9-β-ᴅ-ribofuranosylpurine (2) were isolated as the active principles and 3,5-dichloro-4-methoxybenzoic acid (3) was obtained from cultures of Stropharia squamosa. The corresponding alcohol (4) and aldehyde (5) previously isolated from several basidiomycetes, were also active in this test system. In a screening of fungal metabolites, 1-methoxy-8-hydroxynaphthalene and 1,8-dimethoxynaphthalene inhibited biosynthesis of DHN melanin.

Among the inhibitors identified, compounds 3 -5 were the most selective ones. They were the only metabolites without cytotoxic activities.
Glycerol Inhibits or Uncouples the Plasma Membrane (Ca2++Mg2+)ATPase of Kidney Proximal Tubules Depending on the Ca2+ Concentration
Authors: Sola-Penna Mauro , dos Passos Lemos Adriana , Vieyra Adalberto
Published: August 2018

In this report it is shown that glycerol (0.5-10% v/v) stimulate the C12-E9-solubilized renal (Ca2++Mg2+)ATPase in the presence of low concentrations of free Ca2+ (< 10-6ᴍ). At 4% (v/v), the polyol decreases the K0.5 for Ca2+ from 1.15 to 0.22 μᴍ

at the high-affinity site, and a very-high-affinity Ca2+ component appears. This component has a K0.5 ≤10-9 ᴍ and its maximal velocity is about one-third that of the fully activated enzyme (at 10-20 μᴍ Ca2+), which is not affected by glycerol (21.1 and 20.2 nmol·mg-1 ·min-1 in the absence and presence of the polyol, respectively). The low-affinity, inhibitory component of the Ca2+ curve (50-1000 μᴍ ) is also unaffected by glycerol. With 0.07 μᴍ free Ca2+ and soluble enzyme, the stimulatory effect of glycerol saturates at ≈10% (v/v). In contrast, with 17 μᴍ free Ca2+, glycerol has little effect up to 10% (v/v), and then progressively inhibits ATPase activity. These data indicate that the effect of the polyol is modulated by the occupancy of the high-affinity Ca2+ sites. In native vesicles, the stimulation promoted by low concentrations of glycerol at low concentrations of Ca2+ is accompanied by inhibition of active Ca2+ transport, indicating that, in these conditions, the polyol uncouples ATPase activity and ATP-driven Ca2+ influx.
Collybial, a New Antibiotic Sesquiterpenoid from Collybia confluens (Basidiomycetes)
Authors: Simon Brigitte , Anke Timm , Andersb U. , Neuhausb M. , Hansske F.
Published: August 2018

A new antibiotic was isolated from fermentations of an american strain of Collybia confluens. Its structure was elucidated by spectroscopic methods as 2,10,10-trimethal-4-oxo-tricyclo[7.2.0.02.5]undec-6-en-carbaldehyde (with the relative stereo chemistry IS, 2R, 5R, 9R) (1). The inhibitor, which was named collybial, is structurally related to koraiol, a sesquiterpenoid isolated from Pinus koraiensis (Khan V. A. (1979), Khim. Prir. Soedin 5, 652-658).

Collybial inhibited the growth of Gram-positive bacteria at concentrations starting from 21.5 μm . The propagation of vesicular stomatitis virus (VSV) in baby hamster kidney (BHK-21) cells was inhibited by 21.5 μm collybial. Cytotoxic effects on BHK cells were observed at 5 fold higher concentrations.
Effects of Pharmacological Agents on Ecdysteroid Synthesis in vitro in Ovaries and Abdominal Integument from Female Adult Crickets, Gryllus bimaculatus de Geer (Ensifera, Gryllidae)
Authors: Lorenz Judith , Lenz Margit , Hoffmann Klaus H.
Published: August 2018

In female adults of Gryllus bimaculatus, ovaries as well as the abdominal integument produce free and conjugated ecdysteroids in vitro (Hoffmann et al., 1992). The aim of the current study was to determine the influence of various potential ecdysteroid biosynthesis effectors (RH 5849, KK 42, diflubenzuron, ketoconazole, azadirachtin, acetylenic and allenic cholesteryl derivatives B1, B6, AL2), and also of the protein synthesis inhibitor cycloheximide, on net release of moulting hormones in vitro by the adult ecdysteroid sources. All the compounds examined can be divided into four groups due to their different effectiveness on both the ecdysiosynthetic tissues. The non-steroidal ecdysteroid agonist RH 5849 (group 1) enhanced ecdysteroid synthesis in ovaries, but inhibited hormone production in the abdominal integument. Treatment in vitro with diflubenzuron (dimilin) and cycloheximide (group 2) strongly reduced ovarian ecdysteroid synthesis whereas they were hardly effective on integumental hormone production. The group 3 compounds (ketoconazole, B1, B6, AL2, azadirachtin A) demonstrated a stronger inhibitory effect on the abdominal integument than on the ovary. The imidazole compound KK 42 (group 4) was a very potent effector of ecdysteroid biosynthesis in both hormone sources.
The Biflavonoid Pattern of the Moss Bartramia ithyphylla (Bartramiaceae, Musci)
Authors: López-Sáez José Antonio , Pérez-Alonso María José , Velasco-Negueruela Arturo
Published: August 2018

From Bartramia ithyphylla the following five biflavonoids were isolated: philonotisflavone, 2,3-dihydrophilonotisflavone, dicranolomin, 5′,3′′′-dihydroxyamentoflavone and 5′-hydroxyamentoflavone.
Flavonoids from Some Frullania Species (Hepaticae)
Authors: Kraut L. , Scherer B. , Mues R. , Sim-Sim M.
Published: August 2018

From Frullania teneriffae 5 known flavone aglycones and 6 flavone glycosides were isolated, among them the new 6-OH-luteolin-6-O-β-ᴅ-glucoside-7-O-β-ᴅ-glucoside-6′′′-(3-hydroxy-3-methylglutaroylester). F. cesatiana contains 2 flavone-di-C-glucosides and the new 6-OH-luteolin-7-O-β-ᴅ-glucoside-6′′-(3-hydroxy-3-methylglutaroylester)-3′-O-glucuronide.

The phenolic pattern of F. eboracensis was compared to that of F. muscicola. The known 6-OH-luteolin-7-O-β-ᴅ-glucoside-6′′-(3-hydroxy-3-methylglutaroylester) was identified from F. gibbosa and F. arecae.
Partially N-Deacetylated Chitin Oligomers (Pentamer to Heptamer) are Potential Elicitors for (+)-Pisatin Induction in Pea Epicotyls
Authors: Akiyama Kohki , Kawazu Kazuyoshi , Kobayashi Akio
Published: August 2018

Oligomers (dimer to heptamer) of chitosan and their partially/completely N-acetylated derivatives were examined for (+)-pisatin-inducing activities in pea epicotyl elicitor assay at concentrations ranging from 6.25 to 100 μg/ml. The structures of the oligomers were analyzed by 1H NMR and MALDI TOF MS spectrometers. The chitosan oligomers from dimer to tetramer were inactive, while the pentamer exhibited a moderate activity at 100 μg/ml. The hexamer showed a pronounced activity at 100 μg/ml, whereas the oligomer had no activity at the higher concentrations. Although the chitosan heptamer induced a moderate amount of (+)-pisatin (ca. 60 μg/g fr. wt.) at 50 μg/ml, the oligomer did not elicit pisatin formation at 100 μg/ml. The dimer to tetramer of both partially N-deacetylated chitin (DAC) and chitin were totally inactive. The DAC pentamers (d.a. 31%, 52%), DAC hexamers (d.a. 26%, 41%), and DAC heptamers (d.a. 26%, 36%) exhibited significant elicitor activities at lower concentrations (6.25-25 μg/ml) than the native chitosan oligomers. The chitin pentamer to heptamer had weak or no activity. Both glucosamine and N-acetylglucosamine were inactive in the assay. These facts suggest that the DAC pentamer to heptamer may act as elicitors for pisatin induction in pea-fungus interactions.
1H NMR and Calorimetric Measurements on Rabbit Eye Lenses
Authors: Gutsze Aleksander , Bodurka Jerzy , Olechnowicz Robert , Buntkowsky Gerd , Limbach Hans-Heinrich
Published: August 2018

The dynamic properties of water molecules in the rabbit lens were studied by proton nuclear magnetic resonance line shape analysis, measurements of relaxation times as a function of temperature and calorimetric measurements. The experiments prove, as already suggested by other authors, that there are two types of water in the lens of rabbit eyes, namely bound unfreezable hydration water and bulk freezable water. Line shape analysis and relaxometry showed, that this two types of water exist in two different environments, which may be identified as the nucleus and the cortex of the lens. The line shape analysis showed furthermore that water molecules in the rabbit lens has a common spin lattice relaxation time (T1), but two different transverse relaxation times (T2A and T2B). The tentative model of fast water exchange on the T1 time scale and slow water exchange on the T2 time scale, was used to explain experimental proton relaxation data of the rabbit lens. An estimation for this exchange rate Kex by comparing it to the relaxation times is given (T-1
1 ≪ kex ≪ T-1
1). It has also been shown by a calorimetric measurements, that the lenses can be easily undercooled to temperatures well below the freezing point of water. The achievable maximum undercooling temperature of the lens is a function of the cooling rate KC , therefore it has to be considered as an experimentally adjustable parameter which is not characteristic for the investigated sample. Thus it must be noted that any previous discussions about the specific value of the temperature of water crystallisation in biological systems need to be carefully reconsidered.
Kinetics of Metabolism in Human Kidney Transplants Measured by Dynamic 31P NMR Spectroscopy
Authors: Möller Harald E. , Gaupp Andreas , Vestring Thomas , Dietl Karl-Heinz , Vermathen Peter , Buchholz Bernhard , Peters Peter E.
Published: August 2018

The technique of ex vivo 31P NMR spectroscopy has been used for the investigation of metabolic turnover in 15 cadaveric human kidneys obtained from brain-dead donors for transplantation. Measurements were carried out at 1.5 T time-dependently during regular hypothermic storage in histidine-tryptophan-α-ketoglutarate solution. The minimum delay between explantation and spectroscopy was 2 h 41 min. In one case of a discarded organ the measurements could be extended over a period of 161 h 35 min. A detailed kinetic model describing monoexponential ischemic phosphate turnover, which accounts for various interrelations of the NMR visible metabolites, has been derived. Averaged velocity constants of the decays of nucleotides and phosphomono- and -diesters ranged from 0.0047 to 0.294 h-1 at approximately 4° C. Intracellular pH decreased monoexponentially with an averaged velocity constant of 0.31 h-1.
Semiochemicals of the Scarabaeinae, V*: Characterization of the Defensive Secretion of the Dung Beetle Oniticellus egregius
Authors: Burger B. V. , Petersen W. G. B. , Tribe G. D.
Published: August 2018

Using techniques that were developed for the concentration and analysis of airborne or­ganic volatiles, methyl salicylate and 1,4-benzoquinone were found to be the only two com ­ pounds present in detectable quantities in the effluvium of Oniticellus egregius. These two compounds, previously identified in the defensive secretions of other arthropods, are pre­sumed to be produced as a defense mechanism against predators, such as birds. Methyl salicylate and 1,4-benzoquinone have thus far not been found to occur in other Scarabaeinae.
The Response of Rat Serum Lipids to Diets of Varying Composition or Contaminated with Organochlorine Pesticides
Authors: Boll Meinrad , Weber Lutz W. D. , Stampfl Andreas
Published: August 2018

The effects of different diets (high carbohydrate, high protein, high fat) and diets contaminated with polychlorinated biphenyls (PCBs) and/or γ-hexachlorocyclohexane (lindane) on the levels of serum triglycerides, cholesterol and phospholipids were investigated in Wistar rats. Serum triglyceride levels differed significantly among the diets, while those of cholesterol and phospholipids were much less affected by the diet composition. A change in diet composition resulted in a gradual adaptation to the lipid levels characteristic of the new diet with major variations including oscillations. There was, however, no specific component of a diet that could be associated with any specific change in serum lipids. While feed deprivation decreased the serum lipids (40-65% in 3 days), refeeding the starved animals caused pronounced increases of the lipids that were different among the diets. The response of the triglyceride levels was the strongest (up to 10 times the starvation levels) followed by those of the phospholipids (4-fold) and cholesterol (2.5-fold). Response of the triglyceride levels peaked within 1 or 2 days of refeeding, whereas those of cholesterol and phospholipids took 4 days to reach the maximum. Feeding PCB-contaminated diets increased the serum lipids in a dose-dependent manner (15-250 ppm). Higher PCB concentrations were increasingly inhibitory (350 ppm) or overtly toxic (> 400 ppm). Elevated lipids returned to the starting levels immediately after peaking (triglycerides) or only after several days (cholesterol, phospholipids) but with an earlier onset at lower PCB concentrations. Refeeding starved animals with PCB- contaminated diets also increased the serum lipids dose-dependently. Feeding lindane-containing diets (50-150 ppm) as well as refeeding animals with lindane diets resulted in a considerable increase of the triglyceride levels, while cholesterol and phospohlipids increased much less. Higher lindane concentrations ( 250 ppm) were inhibitory. The outcome on serum lipid levels on feeding diets contaminated with both PCBs and lindane was basically additive.
Enzymatischer Abbau der Embryonalhüllen des Lanzettfischchens, Branchiostoma lanceolatum, während des Schlüpfens / Hatching through Enzymatic Breakdown of the Embryonic Coats in the Lancelet, Branchiostoma lanceolatum (Cephalochordata)
Authors: Denucé J. Manuel
Published: August 2018

A study was made of the hatching process of the lancelet, Branchiostoma lanceolatum (Amphioxus), under laboratory conditions. Embryos in the early neurula stage (5 to 6 pairs of somites) escape through a hole made in the fertilization envelope, following intensive rotatory movements and partial digestion of the envelope. Using the chromogenic substrate Hide Powder Azure (HPA) at pH 8.0, proteolytic activity was detected in the hatching medium. The effect of various protease inhibitors was investigated. Whereas the activity was only slightly affected by inhibitors of trypsin, chymotrypsin or thiol proteases, chelating agents such as EDTA and 1,10-phenanthroline prevented the degradation of HPA, as well as the breakdown of the vitelline membrane of alcohol fixed oocytes by the protease from hatching fluid. These data suggest the presence of a metalloprotease in the hatching medium. How far this enzyme can be compared with hatching enzymes found in echinoderms and fishes (where they have been identified as matrix degrading metalloproteases), awaits further study of the lancelet enzyme, including its isolation and purification.
A Survey of Quinolizidine Alkaloids and Phenylethylamine Tyramine in Cytisus scoparius (Leguminosae) from Different Origins
Authors: Gresser Gabriele , Witte Ludger , Dedkov Victor P , Czygan Franz-Christian
Published: August 2018

Distribution and content of the quinolizidine alkaloids and phenylethylamine tyramine in various organs of Cytisus scoparius taken from different localities in Germany, Russia, Italy and France were analyzed by capillary GLC. Sparteine and sparteine-derivatives like 11,12- dehydrosparteine are predominant in shoots and flowers whereas lupanine-type alkaloids are mainly accumulated in seeds, pods and roots. During the year no changes within the alkaloid pattern of the young developing shoots could be observed, but the total alkaloid amount increases remarkably at the end of the vegetation period. With respect to the date of harvest only a limited variation of the alkaloid profile and content could be found in shoots, flowers and roots taken from different geographical origins. In comparison the alkaloid pattern of seeds and pods varied considerably which seemed to be correlated with the different states of maturity and not with the geographical origin. Phenylethylamine tyramine is accumulated in flowers, green pods and young developing shoots. In young developing shoots the tyramine content declined drastically during the vegetation period.
Localization of Benzoxazinones that Occur Constitutively in Wheat Seedlings
Authors: Iwamura Hajime , Nakagawa Eri , Hirai Nobuhiro
Published: August 2018

Occurrence and localization of novel antimicrobial and antifeeding compounds in wheat, 2,4-dihydroxy-1,4-benzoxazin-3-one (DIBOA ) and 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA), and their glucosides, were examined by staining wheat plants ( Triticum aestivum L.) in the juvenile stage of growth by ferric chloride. The methanol extracts of the stained plant tissues gave a characteristic blue color, which was shown by spectroscopic and chromatographic analyses to be exclusively due to benzoxazinones. When ferric chloride was applied to the root in the seedlings, the blue color immediately developed, the staining being strongest at the tip region and becoming lighter towards the basal part. The staining pattern of the radicle in the pre-emerging seed was similar to that in the root, but the coleorhiza was not stained. Little staining was observed in the epidermal layer of the leaf sheath in the shoot but the underlying tissue was stained strongly. The foliage leaf folded in the sheath was also stained, but less intense than the sheath tissue. It is suggested that the DIBOA and DIMBOA are produced within the stained region of the leaf and root. Together with previous findings that the benzoxazinones appear constitutively in wheat during the juvenile stage of growth, their localized occurrence in the tissues exposed to microbial and insect attacks suggests that they act as defense compounds during this vulnerable plant stage.
The Chemical Relationship between Fungus and Beetles on Ponderosa Pine
Authors: Hayashi N , Honda K , Hara S , Idzumihara H , Mikata K , Komae H
Published: August 2018

Volatile components of Cryptoporus volvatus attracting three pine beetles (Ischnodactylus loripes, Alphitophagus plagiatus, Bolitophagus felix, family Tenebrionidae) were isolated and found to be a mixture of two monoterpenes and an aliphatic hydrocarbon by means of GC-MS. The attractivity of the fungus for the beetles can be induced by synergistic action of (+)-isopinocamphone, (+)-trans-pinocarveol, and 1,3E , 5Z -undecatriene.
Nutritional Regulation of the Activities of Lipogenic Enzymes of Rat Liver and Brown Adipose Tissue
Authors: Boll Meinrad , Weber Lutz W. D , Stampfl Andreas
Published: August 2018

Nutrition-induced effects on the activity of enzymes of lipogenesis, fatty acid synthase (FAS; EC 2.3.1.85). ATP citrate lyase (ACL; EC 4.1.3.8), malic enzyme (ME; EC 1.1.1.40), glucose-6-phosphate dehydrogenase (G6PDH; EC 1.1.1.49) and 6-phosphogluconate dehy­ drogenase (PGDH; EC 1.1.1.44) were investigated in liver and interscapular brown adipose tissue (BAT) of rats. The lipogenic enzymes could be grouped into two categories according to their response to dietary manipulations; FAS and ACL. both key enzymes of lipogenesis, responded fast and strongly to dietary manipulations. ME, G6PDH and PDGH, enzymes which also contribute to metabolic pathways other than lipogenesis, responded in a more sustained and less pronounced fashion. Feed deprivation caused the specific activities of lipogenic enzymes to decline several-fold. Refeeding of previously fasted (up to 3 days) animals increased the activities dramatically (10-to 25-fold) to far above pre-fasting levels (“overshoot”). Repetition of the fasting/refeeding regimen increasingly impaired the ability of both tissues to synthesize overshooting enzyme activities in the subsequent refeeding period. The fasting-induced decline of the activities was prevented when sugars were provided to the animals via drinking water. The sugars displayed different effectivities; sucrose= glucose> fructose> maltose » lactose. Sugars as the sole nutrient after fasting were also able to induce overshooting enzyme activities. Again, activities of FAS and ACL responded in a more pronounced fashion than the other three enzymes. Transition from feeding one diet to feeding a new diet of different composition led to adaptation of the lipogenic enzyme activities to levels characteristic for the new diet. Replacing a low-carbohydrate with a high-carbohydrate diet proceeded with major alterations of enzyme activities. This process of attaining a new level took up to 20 days and involved pronounced oscillations of the specific activities. In contrast, when a high-carbohydrate diet was replaced with another diet, particular one high in fat, transition to new enzyme activities was completed within 2 -3 days and proceeded without oscillations. All dietary manipulations caused more pronounced responses in young (35d-old) than in adult (180d-old) animals.
Oxidation of D-(-)-Ribose with H2O2 and Lipid Hydroperoxides
Authors: Jahn Michael , Spiteller Gerhard
Published: August 2018

ᴅ-(-)-ribose was subjected to oxidation with equimolar amounts of H2O2/Fe2+ and 13-hydro-peroxy-9-cis-11-trans-octadecadienoic acid/Fe2+. Smaller carbohydrates, carbonyl compounds, hydroxy acids and polyols were produced. Identification of carbonyl compounds was achieved by trapping with pentafluorobenzylhydroxylamine hydrochloride (PFBHA-HCl). All products were identified by GC/MS after derivatization with N-methyl-N-trimethylsilyl-trifluoroacetamide (MSTFA). The reactions were repeated with ᴅ-[13C1]-ribose in order to reveal the mechanism of oxidation. A possible reaction pathway is outlined starting by removal of hydrogens from C-H bonds.
Accumulation of Protoporphyrinogen IX Induced by Acifluorfen Methyl
Authors: Sumida Motoo , Niwata Shinjiro , Tanaka Takaharu , Furuno Tadahide , Nakanishi Mamoru , Wakabayashi Ko , Böger Peter
Published: August 2018

Confocal fluorescence microscopic images were used to investigate the accumulation site of protoporphyrin IX (PPIX) within liverwort cells (Marchantia polymorpha L.) treated with peroxidizing herbicides as acifluorfen methyl (AFM). A high level of PPIX accumulation was observed in the cells during 12 h to 24 h after the addition of AFM . The results obtained from confocal fluorescence microscopic images gave clear evidence that the accumulation of PPIX occurred only in the chloroplasts, but was not observed in the cytosol or at the plasma membrane. The presence of PPIX in the chloroplasts strongly suggests that protoporphyrino­ gen (Protogen) accumulates by inhibition of protoporphyrinogen oxidase (Protox) which is the target enzyme for peroxidizing herbicides. The plastidic occurrence of PPIX provides evidence of either the presence of an additional herbicide-resistant Protox or of a non-enzy-matic Protogen-oxidation system in the Marchantia chloroplast.
Copper Ion Inhibition of Electron Transport Activity in Sodium Chloride Washed Photosystem II Particle Is Partially Prevented by Calcium Ion
Authors: Sabat Surendra Chandra
Published: August 2018

The inhibitory effects of copper ion (Cu2+) on the photosynthetic electron transport func­tion was investigated both in NaCl washed (depleted in 17 and 23 kDa polypeptides) and native (unwashed) photosystem II membrane preparations from spinach (Beta vulgaris) chlo-roplasts. Copper in the range of 2.0 to 15 μᴍ strongly inhibited the electron flow from water to 2,6-dichlorobenzoquinone in NaCl washed particles in a concentration dependent manner. Com plete inhibition was noticed at 15 μᴍ Cu2+. Oppositely in native membranes, 15 μᴍ C u2+ inhibited only 10-12% of control activity. It was found that calcium ion (Ca2+) significantly reduced the Cu2+ inhibition of electron transport activity. The Ca2+ supported prevention of Cu2+ toxicity was specific to Ca2+. Further analysis indicated that both Cu2+ and Ca2+ act competitively. Since Ca2+ is known to have stimulating/stabilizing effect at the donor side of photosystem II, it is therefore suggested that Cu2+ in NaCl washed particles exerts its inhibi­tory effect(s) at the oxidizing side of photosystem stimulates/stabilizes the oxygen evolution.
The Catalytic Mechanism of Tyrosine Phenol-Lyase from Erwinia herbicola: The Effect of Substrate Structure on pH-Dependence of Kinetic Parameters in the Reactions with Ring-Substituted Tyrosines
Authors: Faleev N. G. , Spirina S.N. , Ivoilov V. S. , Demidkina T. V. , Phillips R. S.
Published: August 2018

Apparently homogeneous tyrosine phenol-lyase (TPL) from Erwinia herbicola has been prepared by a new method. The pH-dependencies of the main kinetic parameters for the reactions of Erwinia TPL with tyrosine, 2-fluorotyrosine, 3-fluorotyrosine, 2-chlorotyrosine, and 3.4-dihydroxyphenylalanine (DOPA ) have been studied. The pattern of pH-dependence of Vmax depends on the nature of the substituent in the aromatic ring. For the substrates bearing small substituents (H, 2-F, 3-F) Kmax values were found to be pH-independent. For 2-chlorotyrosine and DOPA Vmax decreased at lower pH, the effect being described by equation with one pKa. Generally two bases are reflected in the pH dependence of Vmax/Km. The first base, probably is responsible for the abstraction of a-proton, while the second one, interacts with the phenolic hydroxyl at the stage of binding. The reaction of TPL with DOPA differs from the reactions with other tyrosines by the requirement of an additional base which is reflected in the pH-profiles of both and Vmax/Km. For the reaction of TPL from Citrobacter intermedins with DOPA only Vmax/Km values could be determined. The activity of Citrobacter enzyme towards DOPA is considerably less than that of E. herbicola enzyme, and its maximal value is attained at higher pH.
(+)-10α-Hydroxy-4-muurolen-3-one, a New Inhibitor of Leukotriene Biosynthesis from a Favolaschia Species. Comparison with Other Sesquiterpenes
Authors: Zapf Sylvia , Wunder Annette , Anke Timm , Klostermeyer Dörte , Steglich Wolfgang , Shan Rudong , Sterner Olov , Scheuer Werner
Published: August 2018

A new inhibitor of leukotriene biosynthesis, (+)-10α-hydroxy-4-muurolen-3-one (1), was isolated from fermentations of Favolaschia sp. 87129. Its structure was established by spectroscopic methods. The compound exhibited no antifungal or antibacterial activities.

The effects of 1 on leukotriene biosynthesis were compared with (+)-T-cadinol, (-)-3-oxo-T-cadinol, and (+)-3a-hydroxy-T-cadinol, three related sesquiterpenes.
Lactarane Type Sesquiterpenoids as Inhibitors of Leukotriene Biosynthesis and Other, New Metabolites from Submerged Cultures of Lentinellus cochleatus (Pers. ex Fr.) Karst
Authors: Wunder Annette , Anke Timm , Klostermeyer Dörte , Steglich Wolfgang
Published: August 2018

Three known sesquiterpenoids of the lactarane and secolactarane type, deoxylactarorufin A (1), blennin A (2) and blennin C (3), have been obtained from cultures of Lentinellus cochleatus (Basidiomycetes) together with the new metabolites (Z)-2-chloro-3-(4-me-thoxyphenyl)-2-propen-l-ol (4) and lentinellone (5), a protoilludane derivative. The structures were determined by spectroscopic investigations. 1, 2 and 3 are potent inhibitors of leukotriene biosynthesis in rat basophilic leukemia (RBL-1) cells and human peripheral blood leukocytes (PBL).
Antiviral Activity of Some Hydroxycoumarin Derivatives
Authors: Galabov Angel S. , Iosifova Tanya , Vassileva Elka , Kostova Ivanka
Published: August 2018

Esculetin (6,7-dihydroxycoumarin) and its diacetate exhibited a marked inhibitory effect on Newcastle disease virus replication in cell cultures at concentrations of 36 jam and 62 jam, respectively. These compounds were selected from ten hydroxycoumarin derivatives through an in vitro antiviral screen involving viruses of the picorna-, orthomyxo-, paramyxo-, and herpes virus families.
Binding and Location of Dipyridamole Derivatives in Micelles: the Role of Drug Molecular Structure and Charge
Authors: Borissevitch Iouri E. , Borges Christiane P.F. , Borissevitch Galina P. , Yushmanov Victor E. , Louroh Sonia R.W. , Tabak Marcel
Published: August 2018

Abstract Binding and localization of the vasodilator and antitumor drug coactivator dipyridamole (DIP) and of its three derivatives, RA14. RA47 and RA25 (DIPD), to cationic (cetyltrimethylammonium chloride), anionic (sodium dodecylsulfate), zwitterionic (N-hexadecyl-N,N-di-methyl-3-ammonio-1-propanesulfonate), and neutral (t-octylphenoxypolyethoxyethanol) micelles was studied using fluorescence, optical absorption and 1H NMR spectroscopy. The analysis of NMR, optical absorption and fluorescence data indicates that the depth of localization of the drugs in the micelles from the surface decreased in the order DIP > RA14 > RA47 > RA25. The binding constants for the neutral drug forms change in the same order in the range of 1400-3100 м-1 for DIP to 80-300 м-1 for RA25. This order is identical with the reported biological activity of DIPD. For the protonated drugs in zwitterionic or neutral micelles the binding constants are reduced by a factor of 20-75.
Occurrence of a Pupal Melanization Reducing Factor in Different Insects
Authors: Starnecker Gerhard
Published: August 2018

A pupal melanization reducing factor (PMRF) controls incorporation of pigments into the cuticle of pupae of the nymphalid butterfly, Inachis io, to adapt their coloration to the background colors of their pupation sites. In the present paper, we report on the presence of PMRF in the central nervous system (CNS) of further butterfly species which exhibit a pupal morphological color adaptation. Interestingly, two butterfly species which do not show such an adaptation, and even two moth species which pupate in cocoons also contained PMRF in their CNS. The ganglionic extracts of non-lepidopteran species did not show a PMRF activity. The occurrence of PMRF (or PMRF-like molecules), therefore, may be restricted to the lepidopteran order
The Oxygen-Dependent Modification of Triacylglycerols and Phospholipids, the Different Way of Initiating Lipid Body Mobilization
Authors: Kindi Helmut
Published: August 2018

For plant seedlings dependent on the breakdown of lipid reserves for gluconeogenesis the onset of lipid mobilization is a critically important process. Until recently, knowledge about the chemical mechanism of the initial breakdown steps has been limited, because the lipolytic activities, characterized by the intracellular localization and the type of substrate, have not always been found. As seedlings that depend on the reserves in lipid bodies may differ in morphology and biochemistry, it is likely that more than one pathway exists. Recent studies with cucumber (Cucumis sativus) cotyledons have shown that a lipid body-associated lipoxygenase, and an O2-dependent reaction, initiate both the destabilization of the phospholipid monolayer and the breakdown of triglycerides. Both types of reactions rely on the particular properties of a lipoxygenase isoform exclusively present in lipid bodies.
Is Isoprene Emitted by Plants Synthesized via the Novel Isopentenyl Pyrophosphate Pathway?
Authors: Zeidler Johannes G. , Lichtenthaler Hartmut K. , May H. Ulrich , Lichtenthaler Frieder W.
Published: August 2018

The incorporation of deuterium labeled 1-deoxy-ᴅ-xylulose into isoprene, emitted by three higher plants upon illumination, was analysed by headspace GC-MS. A high extent of incorporation into isoprene was found, indicating that isoprene is synthesized in higher plants via the novel isopentenyl pyrophosphate pathway, of which 1-deoxy-ᴅ-xylulose-5-phosphate is an intermediate. A new chemical synthesis of methyl [ 1-2H1]-1-deoxy-α/β-ᴅ-xyluloside from ᴅ-xylulose is presented.
On the Requirement of Bound Bicarbonate for Photosystem II Activity
Authors: Govindjee  , Xu C. , van Rensen J. J. S.
Published: August 2018

In photosystem II of plants and cyanobacteria, but not in reaction centers of anoxygenic photosynthetic bacteria, formate is known to inhibit electron flow which is reversed fully upon bicarbonate addition. At issue has been an old controversy whether this effect is on the acceptor or the donor side of photosystem II (PS II). We present here data on chloroplast thylakoids for donor side effects, that is accompanied by acceptor side effects, from measurements on chlorophyll a fluorescence yield changes after light flashes 1-6. Further, sensitive differential infrared gas analyser measurements show that bicarbonate is indeed bound in both maize and pea thylakoid suspensions depleted of CO2 without any inhibitor; here, high rates of electron flow are associated with the presence of a maximum of 0.8 to 1.25 (corrected for residual activity) CO2 per photosystem II reaction center. It is suggested that bicarbonate bound to the acceptor side is required for photosystem II activity , both on the acceptor and the donor sides in the same experiment and in the same sample.
Plural Origins of Molecular Homochirality in Our Biota Part II. The Relative Stabilities of Homochiral and Mixed Oligoribotides and Peptides
Authors: Soares Thereza Amélia , Lins Roberto Dias , Longo Ricardo , Garratt Richard , Ferreira Ricardo
Published: August 2018

By computer simulations -molecular mechanics and molecular dynamics with the amber force field (Weiner et al., (1986), J. Comp. Chem. 7, 2 30-252) -we have determined the stabilities of oligoribotide strands built with ᴅ -and ʟ-riboses, and of peptide chains with ᴅ -and ʟ-amino acid residues. In particular, complementary double-chains of oligoribotides were studied, since they are an important feature of the growing mechanism of modern nucleic acids. Peptide chains on the other hand, grow without need of a template. We found that mixed oligoribotides are less stable than homochiral ones, and that this chiral effect is less noticeable in peptide chains. The results support the interpretation that ʟ-riboses act as terminators to the template-assisted growth of oligo-r-Gᴅ (enantiomeric cross-inhibition; Joyce et al., (1987), Proc. Natl. Acad. Sci. USA 84, 4398-4402). Based on this effect, a chemical pathway is proposed which could, under assumed prebiotic conditions, bypass the hindrance of homochiral growth.
Quinolizidine Alkaloids of Platycelphium vöense (Engl.) Wild (Leguminosae)
Authors: Asres Kaleab , Tei Andreas , Wink Michael
Published: August 2018

13 Alkaloids were identified in leaves and twigs of Platycelphium vöense (a monotypic genus in the tribe Sophoreae) by capillary GLC and GLC-MS. Cytisine, N-methylcytisine, anagyrine and 5,6-dehydrolupanine figured as major and N-formylcytisine, N-acetylcytisine, baptifoline, thermopsine, isolupanine, and rhombifoline as minor alkaloids in both leaves and twigs. Lupanine occurred in considerable amount in the leaves and as a minor component in the twigs. The rare alkaloid, 6β-hydroxylupanine, was detected only in the leaves while N-ethylcytisine was shown to be a minor constituent of the twigs only.
Purification and Characterization of Cytochrome c6 from the Unicellular Green Alga Scenedesmus obliquus
Authors: Wünschiers Röbbe , Zinn Thomas , Linder Dietmar , Schulz Rüdiger
Published: August 2018

Purification of a soluble cytochrome c6 from the unicellular green alga Scenedesmus obliquus by a simple and rapid method is described. The purification procedure includes ammonium sulfate precipitation and non-denaturating PAGE. The N-terminal sequence of the first 20 amino acids was determined and shows 85% similarity and 75% identity to the sequence of cytochrome c6 from the green alga Monoraphidium braunii. The ferrocyto-chrome shows typical UV/VIS absorption peaks at 552.9, 521.9 and 415.7 nm. The apparent molecular mass was estimated to be 12 kD a by SDS-PAGE. EPR-spectroscopy at 20K shows resonances indicative for two distinct low-spin heme forms.
How Tree Roots Gather Oxygen from Soil for Energy Supply by Respiration
Authors: Frick Hans-Joachim , Woermann Dietrich , Grosse Wolfgang
Published: August 2018

The gas exchange between the root system of the European alder (Alnus glutinosa (L.) Gaertn.) and the surrounding soil is studied using four-year-old trees. For the experiments the root system connected to its stump is exposed to gases of different molar mass. The stump is cut above the soil surface and in contact with the external atmosphere. A net convective volume flow of gas from the soil into the roots and out of the stump is observed if the mean molar mass of the gas present in the soil is lower than that present in the intercellular space of the roots. The direction of the convective gas flow can be reversed by increasing the molar mass of the gas present in the soil. These phenomena are governed by Graham 's law of diffusion. They demonstrate the importance of gas convection for the gas exchange in tree roots.
Fluorescence of Chromatin DNA Induced by Antitumoral Naphthalimides
Authors: Stockert J. C. , Cañete M. , Villanueva A. , Juarranz A. , Trigoso C. I. , Braña M. F.
Published: August 2018

Treatment of chicken blood smears and semithin sec­tions from Epon-embedded mouse tissues with aqueous solutions of the 3-aminonaphthalimides FA-142, FA-2043, and FA-2143 induced a strong green-yellow fluorescence of chromatin under violet or violet-blue excitation. Chromatin emission was abolished by previous DNase or hot TCA treatment. The use of 3-methoxy (FA-655) and 3-nitro derivatives (M-4212 and M-12210) resulted in very weak fluorescence of chromatin. Ab­sorption maxima at 346 and 408 nm and an emission peak at 570 nm were observed for the free compound FA-142. Fluorescence properties open new and interesting applications for some of these antitumoral and DNA-intercalating naphthalimides.
Intra-and Interspecific Allelochemical Effects in Three Kalanchoe-Species (Crassulaceae)
Authors: Bär W. , Pfeifer P. , Dettner K.
Published: August 2018

The intra-and interspecific acting allelochemicals of Kalanchoe daigremontiana, K. tubiflora and K. pinnata (Crassulaceae) were isolated and could be identified as p-hydroxybenzoic-, protocatechuic-, gallic-, p-coumaric-and coffeic acid. By measuring length of stems and primary roots of Kalanchoe-daughter plants the intra-and interspecific inhibitory activities of authentic compounds could be demonstrated.
Rare Flavonoids from Odixia and Ozothamnus spp. (Asteraceae, Gnaphalieae)
Authors: Wollenweber Eckhard , Dörr Marion , Beyer Matthias , Roitman James N. , Puttoek Christopher F.
Published: August 2018

Representatives of the genera Odixia and Ozothamnus, Australian Asteraceae belonging to the tribe Gnaphalieae, have been analyzed for the presence of flavonoid aglycones accumulated on leaf and stem surfaces. Fiftytwo more or less lipophilic flavonoids have been identified. Methyl ethers of apigenin, luteolin, kaempferol and quercetin are abundant, while rare methyl ethers of isoscutellarein, 8-hydroxy galangin, herbacetin and gossypetin appear to be characteristic. The distribution of rare flavonoids is discussed
New Insight into Reaction of Iron(III)-peroxide Adduct with Alkanes: an Alternative Model for Cytochrome P-450 and Methane Monooxygenase
Authors: Nishida Yuzo , Ito Sayo , Okuno Takashi , Ohba Shigeru
Published: August 2018

A new mechanism for alkane functionalization by iron(III)-peroxide adducts was proposed, and the importance of electrophilic nature of the metal-peroxide adduct with η1- coordination mode was emphasized. This idea suggests that formation of high-valent ironoxo species occurs most likely when the metal-peroxide intermediate is activated through electronic interaction with both the peripheral organic group and substrate; the latter two act as an electron donor to the peroxide adduct
Calcium/Calmodulin Regulated Cell Wall Regeneration in Zea mays Mesophyll Protoplasts
Authors: Abdel-Basset R.
Published: August 2018

The composition of newly synthesized cell walls starting from enzymatically isolated Zea mays mesophyll protoplasts was studied. The contents of pectin, cellulose and hemicellulose in addition to the wall-associated proteins were followed in the presence of increasing con­centrations of calcium ions with or without the calcium channel blockers like lanthanum, lithium ions, verapamil, nifedipine and the calmodulin antagonist trifluperazine. Pectin accu­mulation was inhibited by all antagonists except lanthanum. Cellulose formation, however, was increased by organic antagonists trifluperazine, verapamil and maximally by nifedipine while it was not affected by the inorganic ions lanthanum or lithium. Hemicellulose accumu­ lated with nifedipine present but significantly decreased by all other antagonists. Added Ca2+ (5 -10 mᴍ) reversed most of the blockers-induced inhibition on pectin and hemicellulose. In the case of cellulose, however, calcium concentration which reversed the inhibitory action of these antagonists was dependent on the antagonist. Starch exhibited little alterations indicat­ ing its minor role in deposition of wall components. Cell wall-associated proteins were negatively affected by lanthanum and verapamil and positively by lithium and nifedipine. Gen­erally, this fraction was found in a negative correlation with pectin levels. Chlorophyll contents were lowered after growth for 48 h; this might be due to repeated cell division. These results are discussed in relation to the mechanism of antagonists and effects of calcium.
Ribosomal RNA Gene Restriction Fragment Diversity amongst Penner Serotypes of Campylobacter jejuni and Campylobacter coli
Authors: Smith S. I. , Olukoya D. K. , Fox A. J. , Coker A. O.
Published: August 2018

Diversity based on ribosomal RNA gene-restriction endonuclease digest patterns was detected amongst forty-seven strains of Campylobacter made up of 38 strains of Campylobacter jejuni and 9 strains of Campylobacter coli. Restriction digests of chromosomal DNA prepared by treating with Hae III were probed with an oligonucleotide specific for Campylobacter 16S ribosomal RNA genes. Seventeen distinct hybridization patterns, each indicating the presence of 2 - 4 copies of the 16S rRNA gene are encoded in Campylobacter DNA. Differences in fragment patterns were observed not only between members of two species, but also between individual strains of the same species. Ribopattern fragments of 8.71, 7.56, 2.81 and 1.0 kb were characteristic of the majority of C. jejuni, whereas 7.59 and 4.68 kb fragments were commonly present in C. coli.

In conclusion, Hae III ribotyping was even more discriminatory than the Penner serotyping of C. jejuni and C. coli, as strains of the same serotype were distinguished.
2,5-DialkyItetrahydrofurans, Common Components of the Cuticular Lipids of Lepidoptera
Authors: Schulz Stefan , Beccaloni George , Nishida Ritsuo , Roisin Yves , Vane-Wright R. I. , McNeil Jeremy N.
Published: August 2018

In more than 50 lepidopteran species 2,5-dialkyltetrahydrofurans were identified as com­ponents of the cuticular lipids. The chain length of these compounds varies between C25 and C37 and both cis-and trans-compounds are present. In addition, previously unknown 2-alkyl-5-(1-hydroxyalkyl)tetrahydrofurans were found in some species. The identification procedure and synthesis of representative compounds are reported.
External Accumulation of Biflavonoids on Gymnosperm Leaves
Authors: Wollenweber Eckhard , Kraut Ludwig , Mues Rüdiger
Published: August 2018

Biflavonoids are well known to occur in many Gymnospermae. Here we report on their occurrence in epicuticular material of a number of species. Several compounds are charac­terized by detailed NMR studies and FAB-MS. They are identified as amentoflavone, bilobe-tin, podocarpus-flavone A, sciadopitysin, dihydrosciadopitysin and cupressuflavone.
Preliminary Report on the Effects of Propolis on Wound Healing in the Dental Pulp
Authors: Bretz Walter A. , Chiego D. J. , Marcucci M. C. , Cunha I. , Custódio A. , Schneider L. G.
Published: August 2018

The purpose of this investigation was to determine the antimicrobial and healing potential of propolis on direct dental pulp exposures. This study used 25 adult male rats. Pulp expo­sures were performed and animals were allocated to propolis and calcium hydroxide (Ca(OH)2 groups. Animals were killed on days 5, 7, 10, and 14. The teeth were routinely processed for histological evaluation. Non-parametric tests were employed to analyze the data. No significant differences were found between study groups on the wound healing of the dental pulp. Both substances were com parable in exhibiting normal reorganization of the pulp and no increased vascularity, and were equally efficacious in maintaining a low inflammatory and microbial cell population as well as in stimulating the formation of reparative dentin.