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1.
Single sensillum recordings from Cydia pomonella male antennae showed three different types of receptor neurons. The most abundant type was most sensitive to the main pheromone compound (E,E)-8,10-dodecadienol, while its response to the geometric isomers E,Z, Z,E and Z,Z was comparable to a tenfold lower dose of (E,E)-8,10-dodecadienol. This neuron type also responded to the four behaviorally antagonistic isomers of (Δ,Δ)-8,10-dodecadienyl acetate, among which it was most sensitive to the E,E isomer. Cross-adaptation studies showed that these compounds were all detected by the same receptor neuron type. Receptor neurons specifically tuned to (E,Z) or (Z,Z)-8,10-dodecadienol were not found, although these two compounds are behaviorally active. A second type of receptor neuron responded to all isomers of (Δ,Δ)-8,10-dodecadienyl acetate and was most sensitive to the E,E isomer. This neuron type did not respond to any of the isomers of (Δ,Δ)-8,10-dodecadienol. A third receptor neuron type was highly sensitive to the plant compound α-farnesene. The finding that the receptor neuron type tuned to the main pheromone compound responded even to strong behavioral antagonists aids the interpretation of ongoing behavioral studies for the development of the mating disruption technique in codling moth. Accepted: 3 March 2000  相似文献   

2.
The methanol extract of Ehretia dicksonii provided (10E,12Z,15Z)-9-hydroxy-10,12,15-octadecatrienoic acid methyl ester (1) which was isolated as an anti-inflammatory compound. Compound 1 suppressed 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced inflammation on mouse ears at a dose of 500 μg (the inhibitory effect (IE) was 43%). Linolenic acid methyl ester did not inhibit this inflammation at the same dose. However, the related compounds of 1, (9Z,11E)-13-hydroxy-9,11-octadecadienoic acid (5) and (9Z,11E)- 13-oxo-9,11-octadecadienoic acid (6), showed potent activity (IE500 μg of 63% and 79%, respectively). Compounds 1, 4 ((9Z,12Z,14E)-16-hydroxy-9,12,14-octadecatrienoic acid), 5 and 6 also showed inhibitory activity toward soybean lipoxygenase at a concentration of 10 μg/ml.  相似文献   

3.
Several compounds having the basic α-ionylideneacetic acid structure were tested in Cercospora rosicola resuspensions. At 100 μm, all the compounds inhibited abscisic acid (ABA) biosynthesis. Time studies with unlabelled and deuterated (2Z,4E)- and (2E,4E)-α-ionylideneacetic acids showed rapid conversions into both (2Z,4E)- and (2E,4E)-4′-keto-α-ionylideneacetic acids as major products. Incorporation of the label into ABA was specific for the 2Z,4E-isomer. Minor products, identified by GC-MS, were (2Z,4E)- and (2E,4E)-4′-hydroxy-α-ionylideneacetic acids and (2Z,4E)-1′-hydroxy-α-ionylideneacetic acid. The conversion to (2Z,4E)-l′-hydroxy-α-ionylideneacetic acid has not been previously reported and was specific for the 2Z,4E-isomer. A time study for the conversion of methyl esters of [2H3]-(2Z,4E)- and [2H3]-(2E,4E)-4′-keto-α-ionylideneacetates showed a slow introduction of the l′-hydroxyl group and specificity for 2Z,4E-isomer. Conversion of the ethyl esters of (2Z,4E)- and (2E,4E)-l′-hydroxy-α-ionylideneacetates into the ethyl esters of both ABA and (2E,4E)-ABA demonstrated that ABA can be formed by oxidation of the 4′-position after the insertion of the 1′-hydroxy group. The ethyl 1′-hydroxy acids were also isomerized to the corresponding ethyl (2Z,4E)- and ethyl (2E,4E)-3′-hydroxy-β-ionylideneacetates. Ethyl (2Z,4E)-1′-hydroxy acid also gave small amounts of ethyl l′,4′-trans-diol of ABA. These results suggest that ABA may be formed through a (2Z,4E)-1′-hydroxy-α-ionylidene-type intermediate in addition to the previously proposed route through (2Z,4E)-4′-keto-α-ionylideneacetic acid.  相似文献   

4.
Summary α,β-Dehydroamino acids are useful peptide modifiers. However, their stereoelectronic properties still remain insufficiently recognized. Based on FTIR experiments in the range ofv s(N-H), AI, AII andv s(Cα=Cβ) and ab initio calculations with B3LYP/6–31G*, we studied the solution conformational preferences and the amide electron density perturbation of Ac-ΔXaa-NHMe, where ΔXaa=ΔAla, (E)-ΔAbu, (Z)-ΔAbu, (Z)-ΔLeu, (Z)-ΔPhe and ΔVal. Each of these dehydroamides adopts a C5 structure, which in Ac-ΔAla-NHMe is fully extended and accompanied by the strong C5 hydrogen bond. Interaction with bond Cα=Cβ lessens the amidic resonance within the flanking amide groups. TheN-terminal C=O bond is noticeably shorter, both amide bonds are longer than the corresponding bonds in the saturated entities and the N-terminal amide system is distorted. Ac-ΔAla-NHMe constitutes an exception. ItsC-terminal amide bond is shorter than the standard one and both amide systems are ideally planar. Ac-(E)-ΔAbu-NHMe shares stereoelectronic features with both Ac-ΔAla-NHMe and (Z)-dehydroamides.  相似文献   

5.
Exposure of deaerated folic acid solutions containing an electron donor to UV radiation (310–390 nm, I = 0.4 W m−2) induced formation of dihydrofolic acid (DHFA), a photoexcitation which gave tetrahydrofolic acid (THFA). Only DHFA was formed in the presence of EDTA (Eo = +0.40 V), while the presence of stronger reductants—NADH (Eo = −0.32 V) and boron hydride (Eo = −0.48 V)—induced photoreduction to THFA. It was demonstrated that UV radiation had no effect on the THFA formylation, giving the coenzyme 5,10-methenyltetrahydrofolic acid and its transformation into another coenzyme, 5-formyltetrahydrofolic acid.  相似文献   

6.
Triticum aestivum L.) and foxtail millet (Setaria italica Beauv.) were found by GC-MS to contain, in addition to bulk sterols, 4-en-3-one steroids including 24-ethylcholesta-4,24(28)Z- dien-3-one (a new steroid), 24-methylcholest-4-en-3-one, 24-ethylcholesta-4,22E-dien-3-one and 24-ethylcholest-4-en-3-one, as well as 5α-steroidal 3-one compounds including 24-methyl-5α-cholestan-3-one, 24-ethyl-5α-cholestan-3-one and 24-ethyl 5α-cholest-22E-en-3-one (in S. italica only). Analysis of free sterol and steryl ester fractions indicated that campestanol and sitostanol were present at high levels in both seeds. These results suggest that the seeds of T. aestivum and S. italica synthesize campestanol from campesterol via 24-methylcholest-4-en-3-one and 24-methyl-5α-cholestan-3-one as has already been demonstrated in Arabidopsis thaliana L., and also produce sitostanol from sitosterol via 24-ethylcholest-4-en-3-one and 24-ethyl-5α-chotestan-3-one. Biosynthetic relationships of campestanol and sitostanol with C28 and C29 brassinosteroids are discussed. Received 4 September 1998/ Accepted in revised form 26 November 1998  相似文献   

7.
Amides in a CH2Cl2 extract from the fruits of Piper retrofractum were detected by HPLC/APCI-MS. Seven new unsaturated amides, together with six known ones, were isolated, and their structures were determined to be N-isobutyl-2E,4E,12Z-octadecatrienamide (1), N-isobutyl-2E,4E,14Z-eicosatrienamide (2), 1-(octadeca-2E,4E,12Z-trienoyl)piperidine (3), 1-(eicosa-2E,4E,14Z-trienoyl)piperidine (4), 1-(octadeca-2E,4E-dienoyl)piperidine (5), 1-(eicosa-2E,4E-dienoyl)piperidine (6), and 1-(eicosa-2E,14Z-dienoyl)piperidine (7) on the basis of chemical and spectroscopic evidence.  相似文献   

8.
Simultaneous separation of E- and Z-guggulsterone, which is the main ingredient of ‘Guggulip', an ayurvedic drug, was accomplished by HPLC on a C18 column using methanol, acetonitrile, buffer and tetrahydrofuran as a mobile phase. The compounds were monitored at 248 nm on a photodiode array detector. The assay method was used for the simultaneous determination of stereoisomers (E and Z) of guggulsterone in spiked serum and dosed (50 mg/kg, p.o.) rats. The recoveries of E- and Z-isomers from serum samples were always greater than 90%. The calibration graph was linear over the range of 25–2500 ng/ml for Z- and E-isomers. Lowest quantitation limit of Z- and E-guggulsterones was 25 ng/ml.  相似文献   

9.
Linoleic acid was transformed by mutant Candida tropicalis M25 and transformations were studied in batch and fed-batch cultures. Cofermentations with palmitic acid as inducer of the fatty acid degradation pathway were performed. Besides the (Z),(Z)-octadeca-6,9-dienedioic acid, (Z),(Z)-3-hydroxyoctadeca-9,12-dienedioic acid and (Z),(Z)-3-hydroxytetradeca-5,8-dienedioic acid were obtained as the main fermentation products. The maximum concentrations of (Z),(Z)-octadeca-6,9-dienedioic acid and (Z),(Z)-3-hydroxyoctadeca-9,12-dienedioic acid reached values of 6.4 g/l and 6.9 g/l respectively. The structures of the products were characterized by chemical and spectroscopic methods. The configuration of the double bonds was not changed during bioconversion. As only one regioisomer of the hydroxylated fatty acid was detected, the hydroxylation is site-specific. Received: 11 November 1996 / Received revision: 11 February 1997 / Accepted: 24 February 1997  相似文献   

10.
5-Oxo-(7E,9E,11Z,14Z)-eicosatetraenoic acid (5-oxo-ETE) has been identified as a non-enzymatic hydrolysis product of leukotriene A4 (LTA4) in addition to 5,12-dihydroxy-(6E,8E,10E,14Z)-eicosatetraenoic acids (5,12-diHETEs) and 5,6-dihydroxy-(7E,9E,11Z,14Z)-eicosatetraenoic acids (5,6-diHETEs). The amount of 5-oxo-ETE detected in the mixture of the hydrolysis products of LTA4 was found to be pH-dependent. After incubation of LTA4 in aqueous medium, the ratio of 5-oxo-ETE to 5,12-diHETE was 1:6 at pH 7.5, and 1:1 at pH 9.5. 5-Oxo-ETE was isolated from the alkaline hydrolysis products of LTA4 in order to evaluate its effects on human polymorphonuclear (PMN) leukocytes. 5-Oxo-ETE induced a rapid and dose-dependent mobilization of calcium in PMN leukocytes with an EC50 of 250 nM, as compared to values of 3.5 nM for leukotriene B4 (LTB4) and >500 nM for 5(S)-hydroxy-(6E,8Z,11Z,14Z)-eicosatetraenoic acid (5-HETE). Pretreatment of the cells with LTB4 totally abolished the calcium response induced by 5-oxo-ETE. In contrast, the preincubation with 5-oxo-ETE did not affect the calcium mobilization induced by LTB4. The calcium response induced by 5-oxo-ETE was totally inhibited by the specific LTB4 receptor antagonist LY223982. These data demonstrate that 5-oxo-ETE can induce calcium mobilization in PMN leukocyte via the LTB4 receptor in contrast to the closely related analog 5-oxo-(6E,8Z,11Z,14Z)-eicosatetraenoic acid which is known to activate human neutrophils by a mechanism independent of the receptor for LTB4.  相似文献   

11.
Lipoxygenases (LOXs) constitute a family of lipid-peroxidizing enzymes that catalyze the oxidation of unsaturated fatty acid containing a (1Z,4Z)-pentadiene structural unit, leading to formation of conjugated (Z,E)-hydroperoxydienoic acid. LOXs are known to be widely distributed in plants and animals. Recently, several microbial LOXs were reported to be involved in the production of hydroperoxy fatty acids. Among the microorganisms that produce hydroxy fatty acids, Pseudomonas aeruginosa PR3 is known to convert linoleic acid to trihydroxy fatty acid, which suggests the involvement of a LOX enzyme. Based on these reports, we identified a novel thermostable LOX from P. aeruginosa PR3 strain. The protein was purified 34.3-fold with a recovery rate of 5.14%. The Km and Vmax values of the purified enzyme were 3.57 mM and 0.73 μmol/min//mg, respectively. Heat stability of the purified enzyme was unexpectedly high with an LD50 of 90 min at 80°C, although P. aeruginosa PR3 is known as a mesophilic bacterium. Substrate specificity of the purified enzyme was restricted only to unsaturated fatty acids carrying a (1Z,4Z)-pentadiene unit.  相似文献   

12.
Phosphorylation has to have been one of the key events in prebiotic evolution on earth. In this article, the emergence of phosphoryl amino acid 5′-nucleosides having a P–N bond is described as a model of the origin of amino acid homochirality and Genetic Code. It is proposed that the intramolecular interaction between the nucleotide base and the amino acid side-chain influences the stability of particular amino acid 5′-nucleotides, and the interaction also selects for the chirality of amino acids. The differences between l- and d-conformation energies (ΔE conf) are evaluated by DFT methods at the B3LYP/6-31G(d) level. Although, as expected, these ΔE conf values are not large, they do give differences in energy that can distinguish the chirality of amino acids. Based on our calculations, the chiral selection of the earliest amino acids for l-enantiomers seems to be determined by a clear stereochemical/physicochemical relationship. As later amino acids developed from the earliest amino acids, we deduce that the chirality of these late amino acids was inherited from that of the early amino acids. This idea reaches far back into evolution, and we hope that it will guide further experiments in this area.  相似文献   

13.
The yeast Candida bombicola (ATCC 22214) grown on primary carbon source glucose (100 g l−1) and secondary carbon, arachidonic acid (2 g l−1) produced mixture of sophorolipids up to 1.44 g l−1. The crude product was a heterogeneous mixture of sophorolipids, which are glycolipids of sophorose linked to the fatty acid through glycosidic bond between ω and ω−1 carbon of arachidonic acid. The derived sophorolipids were isolated by silica gel chromatography using dialysis tubing. The purified sophorolipids were characterized by ESI-MS and FT-IR. Acid hydrolysis of the resolved sophorolipids were characterized by ESI-MS for the presence of 20-hydroxy-5Z,8Z,11Z,14Z-eicosatetraenoic acid (20-HETE) and 19-hydroxy-5Z,8Z,11Z,14Z-eicosatetraenoic acid (19-HETE), compounds of pronounced pharmaceutical importance.  相似文献   

14.
We examined the biosynthetic pathway of abscisic acid (ABA) after isopentenyl diphosphate in a fungus, Cercospora cruenta. All oxygen atoms at C-1, -1, -1′, and -4′ of ABA produced by this fungus were labeled with 18O from 18O2. The fungus did not produce the 9Z-carotenoid possessing γ-ring that is likely a precursor for the carotenoid pathway, but produced new sesquiterpenoids, 2E,4E-γ-ionylideneethane and 2Z,4E-γ-ionylideneethane, along with 2E,4E,6E-allofarnesene. The fungus converted these sesquiterpenoids labeled with 13C to ABA, and the incorporation ratio of 2Z,4E-γ-ionylideneethane was higher than that of 2E,4E-γ-ionylideneethane. From these results, we concluded that C. cruenta biosynthesized ABA by the direct pathway via oxidation of ionylideneethane with molecular oxygen following cyclization of allofarnesene. This direct pathway via ionylideneethane in the fungus is consistent with that in Botrytis cinerea, except for the positions of double bonds in the rings of biosynthetic intermediates, suggesting that the pathway is common among ABA-producing fungi.  相似文献   

15.
[2–14C]-(2Z,4E)-γ-Ionylideneethanol and [2–14C]-(2Z,4E)-γ-ionylideneacetic acid were converted by Cercospora cruenta to [2–14C]-(2Z,4E)-1′,4′-dihydroxy-γ-ionylideneacetic acid and [2-14C]-(2Z,4E)-4′-hydroxy-γ-ionylideneacetic acid, which are intermediates of ABA biosynthesis in C. cruenta.  相似文献   

16.
Summary.  2H-Pyran-2-ones 1 were transformed with various hydrazines into (E)- or (Z)-α,β-didehydro-α-amino acid (DDAA) derivatives 4 (and 7) containing a highly substituted pyrazolyl moiety attached at the β-position. With heterocyclic hydrazines, the products 4 were accompanied also by decarboxylated enamines E-6. In order to separate (E/Z)-mixtures of acids, they were transformed to the corresponding methyl esters 9 and 10 by the application of diazomethane. Catalytic hydrogenation under high pressures with Pd/C as a catalyst resulted in the formation of racemic alanine derivatives 11. Received January 29, 2002 Accepted May 27, 2002 Published online December 18, 2002 RID="*" ID="*"  Dedicated with deep respect to Professor Waldemar Adam on the occasion of his 65th birthday. Acknowledgements We thank the Ministry of Education, Science and Sport of the Republic of Slovenia for the financial support (P0-0503-103). Dr. B. Kralj and Dr. D. Žigon (Center for Mass Spectroscopy, “Jožef Stefan” Institute, Ljubljana, Slovenia) are gratefully acknowledged for the mass measurements. Authors' address: Prof. Marijan Kočevar, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, SI-1000 Ljubljana, Slovenia, E-mail: marijan.kocevar@uni-lj.si  相似文献   

17.
Addition of the amino acids threonine, serine, proline, and arginine to fermentations of the fungus Glarea lozoyensis influenced both the pneumocandin titer and the spectrum of analogues produced. Addition of threonine or serine altered the levels of the “serine analogues” of pneumocandins B0 and B5 and allowed for their isolation and identification. Proline supplementation resulted in a dose-dependent increase in the levels of pneumocandins B0 and E0, whereas pneumocandins C0 and D0 decreased as a function of proline level. Moreover, proline supplementation resulted in an overall increase in the synthesis of both trans-3- and trans-4-hydroxyproline while maintaining a low trans-4-hydroxyproline to trans-3-hydroxyproline ratio compared to the unsupplemented culture. Pneumocandin production and the synthesis of hydroxyprolines was also affected by addition of the proline-related amino acid arginine but not by the addition of glutamine or ornithine. Zinc, cobalt, copper, and nickel, trace elements that are known to inhibit α-ketoglutarate-dependent dioxygenases, affected the pneumocandin B0 titer and altered the levels of pneumocandins B1, B2, B5, B6, and E0, analogues that possess altered proline, ornithine, and tyrosine hydroxylation patterns. Journal of Industrial Microbiology & Biotechnology (2001) 26, 216–221. Received 05 November 2000/ Accepted in revised form 27 January 2001  相似文献   

18.
Extracts of the female sex pheromone gland of the carpenterworm moth, Holcocerus vicarius (Walker) (Lepidoptera: Cossidae), a pest of Ulmus pumila L. (Ulmaceae), were found to contain Z7‐tetradecenyl acetate (Z7‐14Ac), E3‐tetradecenyl acetate (E3‐14Ac), (Z3,E5)‐tetradecenyl acetate (Z3,E5‐14Ac), and Z7‐tetradecenyl alcohol (Z7‐14OH) by coupled gas chromatographic‐electroantennographic detection (GC‐EAD) and coupled gas chromatography‐mass spectrometry (GC‐MS). Field trapping studies with impregnated rubber septa indicated that Z7‐14Ac was essential for attraction of males of H. vicarius. However, the most attractive blend contained Z7‐14Ac, E3‐14Ac, Z3,E5‐14Ac, and Z7‐14OH in a 50:22:17:10 ratio. Our results demonstrated that a blend of Z7‐14Ac, E3‐14Ac, Z3,E5‐14Ac, and Z7‐14OH represented the sex pheromone of H. vicarius. The optimized four‐component lure blend may be useful for monitoring H. vicarius infestations and mating disruption.  相似文献   

19.
Females of the leaf miner moth Phyllonorycter acerifoliella (Z.) [=Ph. sylvella (Hw.)] and Ph. heegerella (Z.) (Lepidoptera: Gracillariidae: Lithocolletinae) release their sex pheromone at the beginning of photophase. The periodicity of the `calling' behaviour of Ph. acerifoliella females was established. Three compounds from calling virgin Ph. heegerella females were collected by the Solid Phase Micro Extraction (SPME) technique and identified as (Z)-8-tetradecenyl acetate (Z8-14:OAc), tetradecyl acetate (14:OAc) and (Z)-8-tetradecenol (Z8-14:OH) in the ratio (88±3):(2±0.6):(10±5) by capillary gas chromatography and mass spectrometry. Field trapping experiments demonstrated that the first two compounds are important for the attraction of conspecific males. Z8-14:OAc was found to be attractive when tested separately, while 14:OAc acted as synergist. The attractivity of the three component blend was reduced by 10% admixture of either (E)-10-dodecenyl acetate (E10-12:OAc) or (Z)-10-tetradecenyl acetate (Z10-14:OAc).Field tests of Z10-, Z8- and E10-14:OAc, identified from Ph. acerifoliella females, demonstrated that the first two compounds were essential for the attraction of conspecific males; so both are sex pheromone components. The attractivity of the three component blend of Z10- Z8- and E10-14:OAc was reduced by 10% admixture of (E)-10-dodecenol (E10-12:OH). The following four semiochemical compounds, Z8-14:OAc, Z8-14:OH, E10-14:OAc and 14:OAc, identified from phyllonoryctid females, as well as two sex attraction antagonists for Ph. acerifoliella and Ph. heegerella males, E10-12:OAc and Z10-14:OAc, are new for the family Gracillariidae. The results of field trapping experiments revealed mechanisms ensuring the specificity of the chemocommunication systems in Ph. acerifoliella, Ph. heegerella and Ph. ulmifoliella (Hb.) moths.  相似文献   

20.
The cranberry weevil Anthonomus musculus Say is a key pest of highbush blueberries (Vaccinium corymbosum L.) and cranberries (Vaccinium macrocarpon Aiton) in the northeastern United States. Previous studies have reported A. musculus adult attraction to traps baited with the aggregation pheromone of the pepper weevil Anthonomus eugenii Cano, likely because these two weevils share similar pheromone blends that differ only in two components. The A. musculus aggregation pheromone contains (Z)-2-(3,3-dimethylcyclohexylidene) ethanol (Z grandlure II), (Z)-(3,3-dimethylcyclohexylidene) acetaldehyde (grandlure III), (E)-(3,3-dimethylcyclohexylidene) acetaldehyde (grandlure IV) and (E)-3,7-dimethyl-2,6-octadien-1-ol (geraniol); whereas A. eugenii produces a pheromone blend that includes (E)-2-(3,3-dimethylcyclohexylidene) ethanol (E grandlure II) and (E)-3,7-dimethyl-2,6-octadienoic acid (geranic acid) in addition to the four A. musculus pheromone components. Here, we hypothesized that differences in pheromone composition between these two species influence A. musculus adult attraction to its aggregation pheromone. To test this, we studied the response of A. musculus to its pheromone blend with and without E grandlure II and geranic acid, a commercial A. eugenii pheromone lure and a no-lure control in highbush blueberry and cranberry fields in New Jersey and Massachusetts, respectively. Regardless of crop type, A. musculus adults were more attracted to their four-component pheromone blend and the blend plus geranic acid than the commercial A. eugenii pheromone and the no-lure controls. The A. musculus pheromone blend plus E grandlure II and the A. eugenii pheromone blend also captured more A. musculus adults than the no-lure control but not compared to the commercial A. eugenii pheromone. Further analysis showed that A. musculus adults are significantly (~27%) less attracted to their pheromone blend if it contains E grandlure II, although the addition of geranic acid did not affect their response. These findings may help guide future efforts towards the development of behaviour-based tools to monitor and manage A. musculus.  相似文献   

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