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1.
Summary Mandibular glands of 3 species ofColletes were analyzed by combined gas chromatograph-mass spectrometry. Linalool, neral and geranial in 311 ratio were present and highly attractive to both sexes in field tests. Linalool has not previously been reported in Hymenoptera.Acknowledgment. We thank S. Vincent for assistance with field work and Ms E.F. Saker for permission to study bees nesting on her property.  相似文献   

2.
Summary The amino acid sequence was compared among the three allelic variants (allozymes) ofsn-glycerol-3-phosphate dehydrogenase inD. virilis, which are detected by one-dimensional electrophoresis. The GPDHf variant was different from the GPDHm by only one substitution of 68-lysine for asparagine; GPDHs differed from GPDHm by substitution of 127-glycine for arginine. No electrophoretically silent substitutions were found in a total of 352 amino acid residues.  相似文献   

3.
Zusammenfassung -Hydroxybutyrat wird im Maushirn in-Aminobutyrat und in verschiedene -Aminosäuren umgewandelt.

Supported by the Medical Research Council of Canada.  相似文献   

4.
Besides the known sarmentogenin 3-O--D-allopyranoside (1) and digitoxigenin-3-O-[-D-xylopyranosyl-(14)-2, 3-di-O-acetyl--D-allopyranoside] (4), four new cardiac glycosides (2, 3, 5 and6) have been isolated from the defensive glands of adults ofChrysolina fuliginosa. The structures of the new compounds were determined by1H NMR at 600 MHz and FABMS. Compounds1–6, present in the adults ofC. fuliginosa, have also been identified in the eggs.  相似文献   

5.
We have recently reported the occurrence of 9(R)-hydroxy-, 9(R)-hydroperoxy- and 9-keto-octadeca-10E,12Z,15Z-trienoic acids (9-HOTrE, 9-HPOTrE and 9-KOTrE) inHydra vulgaris, and their biosynthesis from -linolenic acid (-LA) through the action of an enantioselective 10(R)-lipoxygenase (10-LO). Here we describe the finding of these -LA metabolites as esters to the 2-position of phosphatidylcholine, phosphatidylethanolamine and, in trace amounts, phosphatidylinositol. Small amounts of a compound co-eluting with an authentic standard of 9(R)-hydroxy-octadeca-10E,12Z-dienoic acid, a metabolite potentially derived from the action of 10-LO on linoleic acid, were also found esterified with phospholipids. Since direct peroxidation of membrane lipids has been described, experiments were aimed at establishing whether -LA metabolite-containing phospholipids could originate, inH. vulgaris, from either spontaneous or 10-LO-catalyzed oxidation of phospholipid-bound -LA. Incubation of either unlabelled or radiolabelled PUFA-containing phosphoglycerides withH. vulgaris 10-LO did not result in their peroxidation. This suggests that -LA and LA metabolites are incorporated into glycerophospholipids after their formation by 10-LO, and that, as in mamals, membrane phospholipids may serve as a reservoir for these bioactive compounds. This is the first example in an invertebrate species of lipoxygenase products esterified to phosphoglycerides.  相似文献   

6.
Previous studies conducted in cytosolic extracts of the freshwater hydrozoanHydra vulgaris led to the finding of an abundant 11(R)-lipoxygenase catalyzing the peroxidation of polyunsaturated fatty acid (PUFAs) on the tenth carbon atom from the aliphatic end (10 peroxidation). Here we describe experiments aimed at identifying the actual metabolites generated in vivo by such enzymic activity. Homogenates ofH. vulgaris polyps were analyzed by HPLC. This showed the presence of three major components chromatographically identical to three metabolites obtained when incubating the homogenates with exogenous -linolenic acid (-LA). The presence, in extracts of polyps prelabelled with [14C]--linolenic acid, of radioactive metabolites displaying the same chromatographic properties, substantiated the hypothesis that the natural products isolated in vivo are derived from -LA. Gas chromatographic analyses revealed that this was the most abundant PUFA in both free and phosphoglyceride-bound fatty acid pools. [1H]-NMR analysis of the endogenous substances, carried out in comparison with products obtained from exogenously incubated -LA, indicated that their structures were those of 9-hydroxy-, 9-hydroperoxy- and 9-keto-octadeca-10E-12Z-15Z-trienoic acids (9--HOTrE,-HPOTrE and-KOTrE).Hydra homogenates transformed 9--HPOTrE partly into 9--HOTrE and partly into 9--KOTrE. Chiral phase HPLC conducted on 9--HOTrE established that this metabolite was composed mostly of theR anantiomer. These observations, and the finding that the presence of exogenous arachidonic acid in incubated homogenates significantly reduces the production of -LA metabolites, provide strong evidence that these compounds are produced by an enzymic activity identical to the previously-describedH. vulgaris (R)-10-lipoxygenase. Further experiments suggested that -LA, acting as the native substrate for this enzyme, is mainly esterified on the 2 position ofHydra phosphoglycerides, and that the production of the -LA metabolites described here for the first time from natural sources, can be potentially enhanced in vivo by stimuli activating phospholipase A2.  相似文献   

7.
Summary Carbohydrase activity has been demonstrated in homogenates of the alimentary tracts of late instar larvae ofC. maculatus:-D galactosidase, -D glucosidase and N-acetyl-D glucosaminidase activities were comparable and significantly greater than -D galactosidase,-D glucosidase and -D mannosidase. The effects of pH and substrate concentration are reported. The presence and changes in pattern of non-specific esterase activity in larval and adult gut homogenates is also described.  相似文献   

8.
-Spermophilus brunneus . , 13 18 ,S. brunneus S. townsendii mollis (2n=38) , , ; ;S. brunneus . S. brunneus , Spermophilus.

Supported by National Science Foundation Grants No. GB32114X and No. GB 29131X, and the Sprague Foundation. We thankD. Pozin for technical assistance.  相似文献   

9.
Riassunto È stata studiata con metodi istochimici la distribuzione della 5-3-idrossisteroide deidrogenasi ( 5-3-HSDH) e delle 17-idrossisteroide deidrogenasi (17-HSDH), DPN- e TPN-dipendenti, nell'ovario di gallina ovulante. Mentre la 5-3-HSDH è presente in tutti i tessuti a secrezione steroide dell'ovario, la 17-HSDH è localizzata solo nelle cellule della granulosa.  相似文献   

10.
Zusammenfassung Die Bildung von 11-Carboxy-3, 11, 17-trihydroxy-13-C-nor-5-androstan 11a,17-Lakton aus 3, 17-Diacetoxy-11-hydroxy-12-oxo-5-9(11)-androsten wird beschrieben. Der Mechanismus und die Stereochemie dieser Umwandlung (Retro-Aldolkondensation und Benzilsäureumlagerung) wird diskutiert.  相似文献   

11.
Zusammenfassung (1) Es wurde bei den SeeigelartenParacentrotus ,Arbacia undSphaerechinus sowie den drei BastardenPar ×Arb ,Arb ×Par undPar ×Sphaer für eine Reihe von Entwicklungsstadien die Anzahl der Kerne pro Keim bestimmt (Tabelle). Der morphogenetischen Hemmung der Bastarde entsprechen herabgesetzte Kernzahlen und parallel eine Herabsetzung der DNS-Synthese. (2) Es wurde bei den genannten reinen Arten und den Bastarden derUmsatz der RNS bestimmt. Er geht in allen Fällen, bei den reinen Arten wie bei den Bastarden, der DNS- Synthese parallel.

Our work was supported by a grant from the Schweizerischer Nationalfonds zur Förderung der wissenschaftlichen Forschung. We express our sincere thanks to the Nationalfonds and also to the authorities at the Zoological Station at Naples for generous help and supply of materials and facilities. — This paper is thankfully dedicated byF. Baltzer toF. E. Lehmann for his kind hospitality in the Bernese Institute.  相似文献   

12.
Summary On the basis of comparative chemical and spectral data, the structure of the major saponin, luzonicoside, from the starfishEchinaster luzonicus has been elucidated as2. This is a further example of a novel class of steroidal cyclic glycoside from starfish of the genusEchinaster. Its structure includes a 7, 3,6-dioxygenated-23-oxosteroidal moiety, already found in the saponins ofEchinaster sepositus, and a trisaccharide moiety, -D-galactopyranosyl-(12) -L-arabinopyranosyl-(12)--D-glucuronopyranosyl, bridging C-3 and C-6 of the steroid.This contribution is part of the Progetto Finalizzato Oceanografia e Fondi Marini del C.N.R., Roma.Acknowledgments. We wish to thank Mrs M. Pusset, Laboratoire des Plantes Médicinales du C.N.R.S., Nouméa, for the extraction of starfish and the divers of the Centre Q.R.S.T.O.M. de Nouméa for collection.  相似文献   

13.
Summary We describe here a further Japanese family with pyrimidine 5-nucleotidase (P5N) deficiency diagnosed using a nuclear magnetic resonance (NMR) spectrum, in Kumamoto prefecture where two families having the disease have been reported before. The specific spectra in1H-NMR of P5N deficient erythrocytes were due to three methyl protons of CDP-choline at 3.22 ppm and to H-2, H-8 and ribose-1 of pyrimidine nucleotide phosphate(s) in the lower fields (at 5.82 and 8.00 ppm). The other specificities in31P-NMR spectra were due to CDP-choline, CDP-ethanolamine and UDP-glucose. Those spectra were not detected in other types of hemolytic anemia.  相似文献   

14.
Summary A strain ofClaviceps purpurea, labelled 231 F.I., produced in submerged culture 1200 /ml of a mixture of peptidic alkaloids composed for 30% by -ergokryptine. Cultural media, conditions of culture and development features of a typic fermentation are reported.  相似文献   

15.
Summary Electron microscopy demonstrated the presence of glycocalyx on the cell surface ofChattonella antiqua, which was previously believed to be naked. Histochemical analysis of this structure indicates that the glycocalyx consists of at least two different types of acidic complex carbohydrates, sulfated and nonsulfated, together with a neural carbohydrate-protein complex with 1,2-glycol groups and -D-mannosyl and -D-glucosyl residues.  相似文献   

16.
Using bioassay guided isolation, three novel 12 carbon polyoxygenated fatty acids and a novel abietane diterpene have been isolated from the the chloroform extract of aerial parts ofAeollanthus buchnerianus (Lamiaceae). Rigorous spectroscopic methods were used for compound identification. (Z,Z)-8-acetoxy-5-hydroxydodeca-2,6-dienoic acid and (Z,Z)-5,8-dihydroxydodeca-2,6-dienoic acid inhibited the spore germination ofCladosporium cucumerinum (both with Minimum Inhibitory Dose (MID) values of 1 g) andAspergillus niger (MID 5 and 25 g respectively). Further, they also reduced the hyphal growth ofPythium ultimum. (Z)-5-hydroxy-6,7,8-triacetoxydodeca-2-dienoic acid exhibited short term inhibition of the growth ofCladosporium cucumerinum. The novel abietane diterpenoid, (rel)-14-acetoxyabiet-7-en-18-oic acid inhibited the growth of the gram positive bacteriaBacillus subtilis, staphylococcus aureus andStreptomyces scabies (MIC values 80, 20 and 20 g ml–1 respectively).  相似文献   

17.
18.
Zusammenfassung Nach Eingabe vontrans-Stilben bei Ratten wurden die grössten Mengen im Harn als 3,4,4-Trihydroxystilben, 3,4,4-Trihydroxybibenzyl und 3,3, 4,4-Tetrahydroxybibenzyl nachgewiesen. Die Bibenzylderivate werden nachscheinlich nach Ausscheidung in der Galle von Darmbakterien metabolisiert.  相似文献   

19.
20.
Summary 5- and 5-androstane-17-ol-3-one-17-acetate have been prepared from 5-androstane-6, 17-diol-3-one-17-acetate by a synthesis involving directedHuang-Minlon-reduction.Separation of 5-androstane-17-ol-3-one from its 5-isomer could readily be achieved by crystallisation of their 3-ethylenketals from acetone.  相似文献   

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