Band 38, Heft 3-4

The essential oil of Matricaria chamomilla roots has been investigated. Besides the known compounds for this plant organ trans-β-farnesene,trans-α-famesene, chamomillaester I and II, we found the two spiroether only described for the aeriel parts. β-caryophyllene, cis-caryo hyllene and caryophyllenepoxid are found for the first time in Matricaria chamomilla. One of the main constituents is a hitherto unknown sesquiterpene-alkohol with muurolene-structure. With the aid of spectroscopical data ( 1 H-NMR, 13 C-NMR, MS) we determined its structure. We propose the name chamomillol for the new compound. Besides the known resin ducts longitudinally orientated we found resin ducts transversally orientated and oil cells

From Metzgeria furcata (L.) Dum. and M. furcata var. ulvula Nees. 12 different flavone Cglycosides were isolated and identified; 4 of them are common to both varieties. The detected compounds are three tricetin 6,8-di-C-glycosides, one of them 6-C-β-D-glucopyranosyl-8-C-a-Larabinopyranosyltricetin being a new compound, three luteolin C-glycosides and 6 apigenin Cglycosides. The occurrence o f these flavone C-glycosides in M. furcata is discussed in relation to earlier work on flavonoids in Metzgericeae

From the stem bark of Rhamnus catharticus L. (purging buckthorn) the three main anthraquinone glycosides have been isolated by the new method of droplet-countercurrent-chromatography. Their structures were spectroscopically identified as em odin-8-O-β-gentiobioside, -glucoside and -primveroside. From these the primveroside is a new substance, the gentiobioside has been found for the second time in plant material. The structures were confirmed by 13 C NMR spectroscopy for the first time in O-glycosides of emodin type. Especially the differences in 13 C chemical shifts of the free resp. acetylated aglycones and glycosides are useful parameters for determining the position of O-glycosylation in the 1,8-dihydroxy-anthraquinone derivatives

Rhizomes of Iris pallida and Iris florentina contain - increasing on storage - violet-like smelling C 14 -ketones (irones 1 a-c) which develop by oxidative degradation of C 31 -triterpenoids. The structure of these precursors is reported as well as the structure of respective C 30 -homologues. The unusual C 31 -structures may derive biogenetically from the respective C 30 compounds by a methylation which initiates the formation of the ring-closed irone-moiety

2 H-NMR analysis of the 6a-hydroxypterocarpan phytoalexin pisatin derived in CuCl 2 -treated pea (Pisum sativum) pods from [6,11a- 2 H 2 ]maackiain has demonstrated the retention of all 2 H labels. This establishes that no pterocarp-6a-ene or pterocarp-6-ene intermediate is involved, and thus confirms a direct 6a-hydroxylation mechanism for the biosynthesis of 6a-hydroxypterocarpans from pterocarpans

The investigation of Molopospermum peloponnesiacum (L.) Koch from different locations afforded two different types of essential oils: the first one is characterized by a relatively high content of trim ethylbenzaldehydes, whereas the other type contains relatively high amounts of dillapiole and nothapiole

The constitutive isoflavones genistein, 2'-hydroxygenistein, wighteone and luteone have been isolated in varying amounts from methanolic leaf washings of eight species belonging to the legume genus Lupinus. These four compounds likewise occur in the flower buds, stems, roots and immature pods of L. albus, and in stems and roots of L. angustifolius and L. mutabilis. A minor isoflavone present in L. albus and L. luteus leaf washings has been identified by chemical and spectroscopic procedures as 5,7,4'-trihydroxy-3-methoxy-6-(3,3-dimethylallyl)isoflavone (lupisoflavone). Apart from genistein, 2'-hydroxygenistein, wighteone and luteone, the roots of L. albus also contain alpinumisoflavone, licoisoflavone B and 6,3'-di-(3,3-dimethylallyl)genistein (lupalbigenin)

Improved methods of extracting vincaleucoblastin from leaves and tissue cultures of Catharanthus roseus and of the quantitative determination of this dimeric indole-alkaloid by reflectance densitometry of TLC-plates have been established. Approximately 0.05% VLB were found in the leaves and, using high-performance-thin-layer-chromatography, 0.00013% VLB in callus cultures (not in suspension cultures!) derived from this plant

The fungus Botrytis cinerea, which belongs to the class of ascomycetes, has been analysed for its sterol composition. It is able to produce ergosterol, cerevisterol, lanosterol/dihydrolanosterol and cholesterol besides β-sitosterol. The identification of the sterols is carried out with different analytical methods including mass spectrometry. In the extracts of the mycelium also squalene has been identified

1) In kinetic studies, mevinolin proved to be a highly specific inhibitor of partially purified yeast HMG-CoA reductase (K i = 3.5 nᴍ towards HMG-CoA) and of microsomal HMG-CoA reductase from etiolated radish seedlings (Ki = 2.2 nᴍ). At low concentrations of NADPH, the inhibitor counteracts the sigmoidal response of plant HMG-CoA reductase activity towards the cosubstrate. At higher concentrations of NADPH, the inhibition pattern is of non-competitive type. 2) Our results are extensively compared with that obtained by the use of animal tissue and yeast as an enzyme source in order to discuss model systems probably valid to evaluate properties and regulation of plant as well as yeast HMG-CoA reductase

By ODMR in zero-field the porphyrins of the BChl-biosynthesis in whole cells of Rhodopseudomonas sphaeroides R-26 are investigated. In the optical emission spectrum 11 pigments could be identified using ODM R in combination with emission and excitation spectroscopy. The properties of these pigments were analyzed in respect to their interactions with the surrounding molecules. An energy transfer from the triplet state of Zn-protoporphyrin to the antenna pigm ent singlet system was proved by DE-ODMR. The wavelength dependence of the zfs param eters within the individual emission band is explained by a model of selective spin-orbit-coupling. In the case of the precursors chlorophyllide a and pheophorbide a, for example, we could show that the pigments are bound to proteins via a hydrogen bond to the ketocarbonylgroup of ring V and that porphyrins with a central Mg-atom have an additional bond via a Fifth ligand of the Mg

C-Phycocyanin from the cyanobacterium Spirulina m axim a was digested with pepsin to yield chromopeptides and colorless peptides. This mixture was applied to columns of histidyl-Sepharoseunder a variety of conditions (pH-value, ionic strength of buffer). We found a good separation of several chromopeptides from each other and from colorless peptides due to differential interaction of phycocyanobilin chromophore with the histidyl residue of the gel. The separation is suppressed by the use of imidazole buffer. Control experiments were perform ed with purified chromopeptides and with octyl-Sepharose and DEAE-Sepharose. The nature of interaction which probably involves charge transfer interaction besides hydrophobic and ionic forces is discussed with regard to the significance for phytochrome

Light-induced hydrogen evolution by the blue-green alga Nostoc muscorum is stimulated by sulfide with a rate of about 20 (μmol H 2 per mg chlorophyll and hour stable for about one day at low light intensities (7 W/m 2 ). Oxygen evolution does not impair sulfide-stimulated hydrogen formation. Increased hydrogen evolution is catalyzed by nitrogenase, its activity is not influenced by sulfide. Apparently, sulfide inhibits the hydrogen-uptake pathway(s), thereby increasing net hydrogen evolution. - Furthermore, photosynthetic electron flow is inhibited by sulfide, essentially at the oxidizing side of photosystem II, as was dem onstrated by fluorescence-signal changes. This leads to decreased electron supply of nitrogenase. Hydrogen production apparently is at optim um when both the effect o f sulfide on photosynthesis is moderate and when uptake-hydrogenase activity is abolished

The investigation was directed towards the effects of reaction conditions, substrates and pH on the carboxylation reaction of ribulose-1 ,5-bisphosphate carboxylase-oxygenase in the crude enzyme extracts from several plants. Optimal substrate concentrations (HCO 3 - and RubP) were determined. The highest carboxylase activity was attained with Tris/HCl buffer. The pH activity profile was quite sharp with an optimum at pH 7.8. Purified and crystallized carboxylase yielded a broad optimum curve under the same reaction conditions

The numerical analysis of the oxygen flash yield Y n sequences, alone, does not allow to choose between two models: equal S state misses with non negligible double hits or unequal misses with nearly no double hits. Nevertheless, the comparison of the sequences in different conditions shows that the equal miss model is unrealistic: in very different experimental conditions (non saturating flash, different batch of Chlorella or chloroplasts), a parallel variation of the homogeneous miss and double hit factors is observed. This correlation seems strange within the equal miss model: misses come from incomplete reaction (i.e. for exemple insufficient light) and double hits i.e. double advancement come, in principle, from excessive light or too long flash; for these reasons, opposite variation of misses and double hits as a function of light intensity are expected. Within the equal miss model the inverse is exactly observed: at low flash light intensity (11%) which increases the misses, 16% of double hits are needed, which is quite unrealistic. In contrast, the unequal miss model explains such result quite naturally by a m athem atical property: any theoretical sequence with only a unique S state miss and no double hit can be fitted with homogeneous misses and double hits, which increase in parallel as a function of the damping. Evidence for unequal misses in oxygen flash yield sequence is provided by the heterogeneous properties of the light saturation curves (M. J. Delrieu, Biochim. Biophys. Acta 592, 478-494 (1980)). At high flash intensity, all, excepted the transition S' 2 → S 3 , are saturated; the transition S' 2 -→S 3 is far from saturation and its very large saturating light intensity is actually not known. A comparative study, in the same chloroplast batch, of the oxygen yield patterns with attenuated flashes and of the experimental saturation curves of S states shows that only photochemical misses (due to non saturation) exist. At high intensity, there is only a unique miss for the transition S 2 →S 3 i.e. the probability for this transition is low. A model involving a second acceptor could explain the slow increase of transition probability of S' 2 →S 3 at high flash intensity

The combination of a 3-liter fermentor with a flow-through calorim eter is described. Minimum time-lags are less than 10 s corresponding to maximum therm al peak disturbances of ~ 4 μW. The set up shows an excellent long time stability. Aerobic growth of Escherichia coli K12 in batch cultures was used to test the equipment. Precision is ± 2.1% with regard to the total heat release of 4.94 kJ • I -1 and ± 2.5% with respect to the maximum heat flow of 609 mW • l -1 . The accuracy is comparable with calorimeters using commercial flow mixing cells

When the concentration dependence of an enzymic reaction or a transport process can be described by the sum of two Michaelis-Menten terms, reliable data that relate reaction rate and substrate concentration can be obtained even when as much as 70 per cent of substrate was consumed during the assay. Each data pair consists of the average reaction rate during an assay and the concentration where the instantaneous reaction rate was equal to the average rate. Although that concentration cannot be computed exactly (as it depends on the four kinetic parameters), it may be computed in a good approximation as if the reaction followed the simple Michaelis-Menten relationship. The relative error in the approximated concentration for 1 ≦ K 2 /K 1 ≦ 10 5 and 10 -2 ≦ V 2 /V 1 ≦ 10 2 did not exceed 5 per cent up to 50 per cent of substrate consumption, and did not exceed 10 per cent up to 70 per cent of substrate consumption

ʟ-usnic acid inactivates urease through a process which implicates the blockade of - SH groups in parallel to the formation of inactive polymers. Both ʟ-alanine and ʟ-proline partially reverses the inactivation and effectively diminishes the amount of highly polymerized protein. The amino acids also prevent the linkage of ʟ-usnic acid on the sites of low affinity for the ligand, being then related to the sites of polymerization

Addition of cyclic AMP to normal rabbit reticulocyte lysate brings about substantial increase in protein synthesis programmed by both nuclear and polysomal eukaryotic RNAs. The increase in synthesis is largely nonspecific and the in-vitro translation system is rendered viable for longer periods of time than in the absence of cyclic AMP. This stimulation of translation could be due to the inhibition of protein kinases that are initially activated by secondary structure of RNAs. However, the ability of cyclic AMP to further stimulate methyl mercury or heat denatured RNA indicates that additional mechanisms may be involved in the enhancement of translation

1. Based on a detailed reaction scheme of the phosphorylation process of the sarcoplasmic transport ATPase the inhibition mechanisms of benzoctamine, DIO 9, AMP-PNP and of Ca 2+ -ions at relatively high concentrations (1 ~ 100 μᴍ) were determined. 2. The inhibition mechanisms were analyzed by measuring the γ-phosphate exchange between ATP and ADP and evaluated by applying conventional and an extended Dixon plot procedures. 3. The kinetic patterns of the inhibition were shown to be compatible with the assumed reaction scheme. 4. Each inhibitor combines with definite intermediates: Benzoctamine with the interm ediate species ~ P; DIO 9 with E and MgE and Ca 2+ at relatively hign concentrations with E. 5. The central interm ediate blocked by benzoctamine can partially exist as -benzoctamine which is detected as phosphoprotein after acid denaturation

Furazolidone, on complexing with DNA, led to its thermal stabilization. The increase in transition temperature of DNA (ΔT m ) increased linearly with % A - T content. Increasing concentration of Cu(II) ions progressively lowered the transition tem perature of DNA, but Cu(II) ions were not equally effective in lowering the transition temperature of furazolidone-DNA complex. When equimolar amounts of Cu(II) ions and furazolidone were used, the stabilisation effects of furazolidone prevailed over the destabilisation effect of Cu(II) ions

Phage T4 is known to have a linear duplex chromosome that is circularly perm uted and terminally repeated. We found, by denaturation and self-reannealing experiments, that circular permutation in T4 native DNA is not random. Their multimodal distribution of permutation is compatible with the “headful packaging” model with the additional specifications that the encapsulation of DNA starts at several sites and these are not random distributed

The amount of precipitating antibodies in monospecific lipid- and protein antisera was determined by quantitative precipitation reactions according to the methods of Heidelberger and Kendall. Antisera were obtained by immunization of rabbits. Fragments of the thylakoid membrane from Antirrhinum chloroplasts were used as antigens for the binding of antibodies. These fragments had a diameter of 100 Å. They were composed of 51% proteins and 39% lipids. It was found that antisera to the lipids mono-, tri- and digalactosyl diglyceride, sulfoquinovosyl diglyceride and phosphatidyl glycerol contained 20 to 92 μg precipitating antibodies per ml serum. In antisera to the coupling factor of photophosphorylation, cytochrome f, a polypeptide with the apparent MW 24000 and a serum to the total protein of the lam ellar system 23 to 99 (ig were found. In chloroplast antisera the amount of all precipitating lipid- and protein antibodies amounted to 765 μg per ml. The described antisera originated from blood that had been withdrawn from the test animals 4 to 10 week after antigen injection

On treatment with sodium cholate, the phase transition temperature (T c ) of multilamellar liposomes derived from dipalmitoyl phosphatidylcholine (DPPC) progressively decreased with increasing cholate: lipid-P molar ratio. A molar ratio of 4.5 caused a one degree depression in T c . The unilamellar cholate vesicles of DPPC exhibited the same T c as that of the multilamellar ones. The formation of unilamellar vesicles from the multilam ellar ones by cholate treatm ent was investigated by electron microscopy

The addition of a threshold amount of ClO 4 -ions induces a precipitation of dipalmitoylphos- phatidylcholine vesicles predominantly in the crystalline state. Other anions show a similar but less pronounced behaviour. The effect follows the chaotropic order of the regarded anions. The influence of alkaline cations is described but difficult to characterize. Measurements on the mechanism of this precipitation reveal that the vesicles stay intact and that vesicle-vesicle fusion can almost be excluded in the time-domain studied (seconds to minutes). The flocculation of vesicles induced by the addition of chaotropic ions is assumed to be the origin for the observed precipitations.

Utilizing centrifugal elutriation, early and late S-phase cells were separated from 4, 8 and 12 h anaerobically cultured Ehrlich Ascites tumor cells strain Karzel. The cytokinetic properties of these fractions after reaeration were studied by flow cytometry and the BrdU-H 33258-technique of flow cytometry. After a 4 h period of anaerobiosis, growth of early S-phase cells is not changed, 8 h deprivation of oxygen causes a delay of cell cycle progression, while the main fraction of 12 h anaerobically treated early S-populations did not divide after reaeration within 24 h. In comparison to early S-phase cells the cell cycle progression of the main fraction of late S-period is accelerated after a 4 h exclusion of oxygen. A fraction of 8 h anaerobically pretreated late S-cells continues to cycle, but a considerable number reinitiates DNA synthesis without preceeding division. Cells with DNA content up to 8 c are detected by flow cytometry. 12 h anaerobically cultured late S-cells do not divide after reaeration, a large number of these cells starts again to synthesize DNA. A considerable part of tetraploid cells retain viability, divide and enter a new cell cycle, another part of the cells disintegrates

Within the rove beetle subtribe Philonthina (Staphylinidae) there are found paired abdominal defensive glands which show a bipartition and are characterized by an unique, evaginable evaporation tissue which is described for the first time. The gland chemistry is found to be characterized by at least 27 compounds. The main component is represented by the alkaloid actinidine, minor components are iridodial, three possible monoterpenoid iridodial precursors, an octadecenole and two series o f hydrocarbons and acetates which are partly branched and unsaturated. It could be shown, that the separated gland of the evaporation tissue, whose evagination was studied, has no different synthetic abilities as compared with the main gland system. Chemotaxonomic results according to Hennig’s principle reveal an isolated position of the rove beetle tribe Quediini within the subfamilies X antholininae and Staphylininae. The morphologically unique defensive gland of the Xantholininae may be homologized with other abdominal glands of the Staphylinina and Philonthina, based on the common presence of iridoid defensive components

Thin layer chromatography of retina extracts from Calliphora yielded, instead of retinal (or retinaloximes after NH 2 OH treatm ent) a considerably more polar aldehyde or its corresponding oximes. That these compounds originate from the chrom ophoric group of the visual pigment was shown by the occurrence of different stereoisomers in the extracts depending on the colour with which the intact visual pigment complex was previously illuminated. The absorbance maximum of the oxime found after blue illumination is the same as that of all-trans-retinal-oxime (356 nm). This spectral accordance means that previous spectral evidence for retinal as the chromophoric group of fly visual pigment is not conclusive. Flies raised on a carotenoid deficient diet enriched with the hydroxy-xanthophyll lutein possess a high visual pigment content. This points to a hydroxy- xanthophyll as a possible precursor of the chromophoric group

Lathyrus sativus was investigated for the nature of its phytoalexin response with the result that leaflets, immature pods, and seeds were induced to produce 6a-hydroxy- 3-methoxy-8,9-methylenedioxypterocarpan (pisatin). Evidence is presented for the metabolism of pisatin, by the wound pathogen Botrytis cinerea, to a phenolic congener, 3,6a-hydroxy-8,9-methylenedioxypterocarpan

Cannabis resin (Cl) produced a dose-related increase in rat brain serotonin concentrations, whereas restraint stress produced maximal rise of the neurotransmitter concentrations at 1 h, followed by a tendency to normalise by 4 h. The prostaglandin (PG) synthesis inhibitors, diclofenac and paracetamol, antagonized Cl and restraint stress induced rise in serotonin concentrations. The findings lend credence to earlier reports that PG synthesis inhibitors antagonize serotonin-mediated neuropharmacological actions of Cl and restraint stress in rats