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1.
The breakdown of lycopene in the presence of reactive oxygen and reactive nitrogen species has been studied in order to identify key in vitro intermediates. These compounds may in turn be produced as metabolites in the body and may have significant physiological properties, such as increased antioxidant capacity. We have studied the in vitro degradation of lycopene in solvent, in plasma and in low density lipoprotein, when challenged with freshly generated gaseous cigarette smoke or free radicals generated in situ by S-morpholinosydonimine at 37°C. The emphasis has been to establish the major intermediates and to compare the data with previous studies using different reactants. We have found that (13Z)-lycopene is the major intermediate in both cigarette smoke and S-morpholinosydonimine reactions (representing ≥60% of the converted (all-E)-lycopene at ~50% depletion). Additionally, (9Z)-lycopene and various (all-E) and (Z)-lycopene epoxides were predominant. Notably, (5Z)-lycopene appeared to be the most stable form of lycopene under the stated conditions. Previous theoretical studies of isomer thermodynamics and rotational energy barriers for carbon double bonds fully support the pattern of isomer production and stability. In contrast to β-carotene studies, nitro-derivatives of lycopene could not be detected. In conclusion, (Z)-lycopene production and (5Z)-lycopene stability may help explain elevated (Z)-lycopene in plasma over (Z)-lycopene content in lycopene-containing foods in the diet.  相似文献   

2.
Lycopene has a large number of geometric isomers caused by E/Z isomerization at arbitrary sites within the 11 conjugated double bonds, offering varying characteristics related to features such as antioxidant capacity and bioavailability. However, the geometric structures of only a few lycopene Z-isomers have been thoroughly identified from natural sources. In this study, seven multi-Z-isomers of lycopene, (9Z,13′Z)-, (5Z,13Z,9′Z)-, (9Z,9′Z)-, (5Z,13′Z)-, (5Z,9′Z)-, (5Z,9Z,5′Z)-, and (5Z,9Z)-lycopene, were obtained from tomato samples by thermal isomerization, and then isolated by elaborate chromatography, and fully assigned using proton nuclear magnetic resonance. Moreover, the theoretically preferred pathway from (all-E)-lycopene to di-Z-isomers was examined with a computational approach using a Gaussian program. Fine-tuning of the HPLC separation conditions led to the discovery of novel multi-Z-isomers, and whose formation was supported by advanced theoretical calculations.  相似文献   

3.
Nineteen carotenoids were identified in extracts of petals of orange- and yellow-flowered cultivars of calendula (Calendula officinalis L.). Ten carotenoids were unique to orange-flowered cultivars. The UV–vis absorption maxima of these ten carotenoids were at longer wavelengths than that of flavoxanthin, the main carotenoid of calendula petals, and it is clear that these carotenoids are responsible for the orange color of the petals. Six carotenoids had a cis structure at C-5 (C-5′), and it is conceivable that these (5Z)-carotenoids are enzymatically isomerized at C-5 in a pathway that diverges from the main carotenoid biosynthesis pathway. Among them, (5Z,9Z)-lycopene (1), (5Z,9Z,5′Z,9′Z)-lycopene (3), (5′Z)-γ-carotene (4), and (5′Z,9′Z)-rubixanthin (5) has never before been identified. Additionally, (5Z,9Z,5′Z)-lycopene (2) has been reported only as a synthesized compound.  相似文献   

4.
The long-chain aldehydes, (8Z,11Z,14Z)-8,11,14-heptadecatrienal, (7Z,10Z,13Z)-7,10,13-hexadecatrienal, and (8Z,11Z)-8,11-heptadecadienal, were concisely synthesized by using Grignard coupling, catalytic hydrogenation with the Lindlar catalyst, and oxidation with Dess–Martin periodinane as the key steps. Particularly, (8Z,11Z,14Z)-8,11,14-heptadecatrienal and (7Z,10Z,13Z)-7,10,13-hexadecatrienal both possessed a seaweed-like odor.  相似文献   

5.
Ovipositor washings from virgin female Cryptophlebia batrachopa (Meyrick) (Lepidoptera: Tortricidae) were analysed by gas chromatography (GC) linked to electroantennography (EAG) and by high-resolution GC. The major EAG-active component in ovipositor washings was shown to be (Z)-8-dodecenyl acetate with less than 0.5% of the E isomer. GC analysis of ovipositor washings from C. leucotreta confirmed the presence of approximately equal amounts of (Z)- and (E)-8-dodecenyl acetates (Persoons et al., 1977). When pure (Z)-8-dodecenyl acetate and mixtures containing up to 50% of the E isomer were tested in the field in Malawi where both Cryptophlebia species occurred, C. batrachopa male moths were caught only in traps baited with 10% or less of the E isomer and highest catches were recorded for the pure Z isomer. By contrast C. leucotretra males were caught predominantly by traps baited with more than 10% E isomer and no catches were recorded for the pure Z isomer. (Z)-8-dodecenyl acetate containing 1% of the E isomer was found to attract male moths of Opogona spp.
Résumé Les produits recueillis par lavages de l'ovipositeur de Cryptophlebia batrachopa Meyr. (Lep. Tortricidae) ont été analysés par chromatographie gazeuse (GC) associée à l'électroantennographie (EAG) et la GC à haute résolution. Le principal constituant actif en EAG provenant des lavages s'est révélé être le (Z)-8-dodécényl acétate avec moins de 0,5% de l'isomère E. L'analyse GC de ces produits de lavage de C. leucotreta ont confirmé la présence d'à peu près les mêmes quantités de (Z) et (E)-8-dodécényl acétates (Persoons et al., 1977). Quand des essais sur le terrain ont été effectués au Malawi, où existent les deux espèces de Cryptophlebia, avec du (Z)-8-dodécényl acétate et des mélanges comprenant jusqu'à 50% de l'isomère E, des mâles de C. batrachopa ont seuls été capturés dans des pièges contenant 10% ou moins de l'isomère E; les captures les plus élevées ont été obtenues avec l'isomère Z pur. A l'opposé, surtout des mâles de C. leucotreta ont été capturés dans des pièges garnis avec plus de 10% d'isomère E, et aucune capture n'a été obtenue avec l'isomère Z pur. Des mâles d'Opogona spp. ont été attirés par du (Z)-8-dodécényl acétate contenant 1% de l'isomère E.
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6.
The both enantiomers of (Z)-5-(1-decenyl)oxacyclopentan-2-one were synthesized starting from resolved acetylenic intermediates. The (R)-form of this lactone is the pheromone of Popillia japonica. The optical purities of the final products were about 90%.  相似文献   

7.
The female sex pheromone of the oriental corn borer, Ostrinia furnacalis Guenée, was presumed to be composed of (Z)-12-tetradecenyl acetate and its geometrical isomer using electroantennogram technique. From the extracts of female moths, the presence of these compounds in a ratio of ca. 3:2 was confirmed by gas-liquid chromatography and gas-liquid chromatography combined with mass spectrometry in selected ion monitoring mode. Since the male moths were not attracted to mixtures of the two synthetic compounds, the presence of minor component(s) was suggested.  相似文献   

8.
A 1:1 mixture of (Z, Z)-3,13-octadecadien-1-ol and its (E, Z)-isomer was synthesized by a Wittig reaction whose stereoselectivity was adjusted to give the products in the required ratio. The corresponding acetate mixture is useful as the attractant for Synanthedon hector.  相似文献   

9.
The present study was undertaken to examine whether lycopene is able to counteract 7-ketocholesterol (7-KC)-induced oxidative stress and apoptosis in human macrophages. Human THP-1 macrophages were exposed to 7-KC (10–25 μM) alone and in combination with lycopene (0.5–2 μM), and we monitored changes in cell oxidative status [reactive oxygen species (ROS) production, NOX-4, hsp70 and hsp90 expressions, 8-OHdG formation] and in cell proliferation and apoptosis. After 24 h of treatment, lycopene significantly reduced the increase in ROS production and in 8-OHdG formation induced by the oxysterol in a dose-dependent manner. Moreover, the carotenoid strongly prevented the increase of NOX-4, hsp70 and hsp90 expressions as well as the phosphorylation of the redox-sensitive p38, JNK and ERK1/2 induced by the oxysterol. The attenuation of 7-KC-induced oxidative stress by lycopene coincided with a normalization of cell growth in human macrophages. Lycopene prevented the arrest in G0/G1 phase of cell cycle induced by the oxysterol and counteracted the increased expression of p53 and p21. Concomitantly, it inhibited 7-KC-induced apoptosis, by limiting caspase-3 activation and the modulatory effects of 7-KC on AKT, Bcl-2, Bcl-xL and Bax. Comparing the effects of lycopene, β-carotene and (5Z)-lycopene on ROS production, cell growth and apoptosis show that lycopene and its isomer were more effective than β-carotene in counteracting the dangerous effects of 7-KC in human macrophages. Our study suggests that lycopene may act as a potential antiatherogenic agent by preventing 7-KC-induced oxidative stress and apoptosis in human macrophages.  相似文献   

10.
(Z)-3-Hexene-1, 6-diol, a new synthon for the synthesis of (Z)-olefinic pheromones, was prepared from 1, 4-cyclohexadiene. This synthon was used in the synthesis of (Z, Z)-3, 13-octadecadienyl acetate, whose high stereochemical purity at C–3 was essential in attracting male Synanthedon tenuis Butler.  相似文献   

11.
Both C?C‐bond isomers of cyclohexadec‐7‐enone ( 6 , Aurelione®) were selectively synthesized via cyclohexadec‐7‐ynol ( 16 ) by ring‐closing alkyne metathesis of icosa‐2,18‐diyn‐9‐ol ( 15 ), employing an in situ‐formed catalyst from Mo(CO)6 and 4‐(trifluoromethyl)phenol. Pyridinium chlorochromate (PCC) oxidation and subsequent Lindlar hydrogenation afforded the (7Z)‐configured isomer (7Z)‐ 6 , while hydrosilylation of the intermediate cyclohexadec‐7‐ynone ( 17 ), followed by desilylation, provided the (7E)‐configured cyclohexadec‐7‐enone ((7E)‐ 6 ). The substrate for the alkyne metathesis was prepared from cycloheptanone ( 7 ) by cycloaddition of chloromethylcarbene to its trimethylsilyl enol ether 8 , and subsequent ring enlargement of the adduct 9 under rearrangement to 2‐methylcyclooct‐2‐enone ( 10 ), which was subjected to Weitz? Scheffer epoxidation and Eschenmoser? Ohloff fragmentation to non‐7‐ynal ( 12 ). Its reaction with the Grignard reagent of 11‐bromoundec‐2‐yne ( 14 ), prepared from the corresponding alcohol 13 by Appel? Lee bromination, furnished the icosa‐2,18‐diyn‐9‐ol ( 15 ). While both isomers of cyclohexadec‐7‐enone ( 6 ) possess warm and powdery musk odors with tobacco‐type ambery accents, (7Z)‐ 6 is more animalic and waxy, whereas (7E)‐ 6 was found to be more floral, sweet, and hay‐like in tonality. Interestingly, however, with odor detection thresholds of 2.0 ng/l air and 2.3 ng/l air, respectively, both (7Z)‐ 6 and (7E)‐ 6 were found to be almost identical in their odor strength, with the (7Z)‐ 6 being only very slightly more powerful.  相似文献   

12.
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   

13.
14.
Carotenogenesis in mung been seedlings has been shown to beunder phytochrome control. Dark-grown seedlings contain moreindividual carotenoids than light-treated ones, but total carotenoidsare greatly increased by light. As expected, chlorophyll wassynthesized after a lag period on transferring etiolated seedlingsto the light, and there was an increase in total chlorophylland a parallel increase in total carotenoids. CPTA [2-(4-chlorophenylthio)-triethylamine hydrochloride]-treatedseedlings showed a decrease in both total carotenoids and totalchlorophylls. The usual effect of CPTA was also observed withmung bean seedlings, namely that lycopene, normally absent,appeared and increased to 17 per cent of total carotenoids afteran eight-day treatment. A cis-lycopene, possibly poly-cis-lycopene,was observed for the first time in CPTA-treated tissues. Onlyin the presence of CPTA but not on its removal was it possibleto show an inverse relationship between ß-caroteneand lycopene. This suggests that CPTA may not act as a cyclaseinhibitor in green tissues, cyclase being the enzyme/s involvedin the cyclization of carotenes. Phaseolus aureus Roxb., mung bean, carotenes, lycopene, xanthophylls, chlorophyll, 2-(4-chlorophenylthio)-triethylamine hydrochloride  相似文献   

15.
As part of continued efforts for the development of new tyrosinase inhibitors, (Z)-5-(substituted benzylidene)-2-iminothiazolidin-4-one derivatives (1a – 1l) were rationally synthesized and evaluated for their inhibitory potential in vitro. These compounds were designed and synthesized based on the structural attributes of a β-phenyl-α,β-unsaturated carbonyl scaffold template. Among these compounds, (Z)-5-(3-hydroxy-4-methoxybenzylidene)-2-iminothiazolidin-4-one (1e, MHY773) exhibited the greatest tyrosinase inhibition (IC50 = 2.87 μM and 8.06 μM for monophenolase and diphenolase), and outperformed the positive control, kojic acid (IC50 = 15.59 and 31.61 μM). The kinetic and docking studies demonstrated that MHY773 interacted with active site of tyrosinase. Moreover, a melanin quantification assay demonstrated that MHY773 attenuates α-melanocyte-stimulating hormone (α-MSH) and 3-isobutyl-1-methylxanthine (IBMX)-induced melanin contents in B16F10 melanoma cells. Taken together, these data suggest that MHY773 suppressed the melanin production via the inhibition of tyrosinase activity. MHY773 is a promising for the development of effective pharmacological and cosmetic agents for skin-whitening.  相似文献   

16.
Conclusion (3Z,6Z,9Z)-1,3,6,9-nonadecatetraene, the synthetic sex pheromone of the female of O. brumata is highly active in attracting males of this species in the field (Germany and Switzerland). No analogous compounds possessing attractivity to O. brumata males have been found up to now, nor did they show any inhibitory effects to the same species.Therefore (3Z,6Z,9Z)-1,3,6,9-nonadecatetraene (I) can be recommended as a good attractant in the prognosis or monitoring of this lepidopteran pest.  相似文献   

17.
Lycopene is a carotenoid with known antioxidant and anti-inflammatory properties. We aimed to evaluate the in vitro and in vivo effects of lycopene on reducing the redox imbalance and inflammation induced by cigarette smoke (CS). For the in vitro study, J774A.1 (macrophages) cells were incubated in the presence of 0.5, 1.0, 2.0, 4.0, 8.0, 10.0 and 25 μM of lycopene for 3, 6 and 24 h or in the presence of 0.1%, 0.25%, 0.5%, 0.625%, 1.25%, 2.25%, 5% and 10% cigarette smoke extract (CSE) for 3, 6 and 24 h to assess cell viability and measurement of intracellular reactive oxygen species (ROS). For the in vivo study, 40 mice were divided into 5 groups: a control exposed to ambient air (CG), a vehicle-control group that received 200 μl of sunflower oil by orogastric gavage, a group exposed to CS and two groups administered lycopene (diluted in sunflower oil) at doses of either 25 or 50 mg/kg/day prior to exposure to CS (LY25+CS and LY50+CS). The total treatment time lasted 5 days. A cell viability decrease was observed at 10- and 25-μM concentrations of lycopene in 3, 6 and 24 h compared with CG. There was an increase of ROS production in 24 h in CS compared with CG. Lycopene concentrations of 1 μM and 2 μM were able to reduce the production of ROS in 24 h compared with CS. In the bronchoalveolar lavage fluid, the total number of leukocytes increased in the CS group compared with the control groups (CG). Administration with lycopene at the highest dose suppressed this CS-induced increase in leukocytes. Lipid peroxidation and DNA damage increased in the CS group compared with that in the controls, and this increase was suppressed by lycopene at the highest dose. In contrast, superoxide dismutase activity decreased in the CS group compared with that in the controls. Catalase activity also increased in the CS group compared with that in both control groups, and this increase was suppressed in LY25+CS and LY50+CS. There was an increase in the levels of tumor necrosis factor-α, interferon-γ and interleukin-10 after exposure to CS, and these effects were suppressed by both doses of lycopene. These data elucidate the role of lycopene as an antioxidant and anti-inflammatory agent in these two models of short-term exposure to CS.  相似文献   

18.
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   

19.
In search of novel natural product-based bioactive molecules, twenty (ten pairs) novel (Z)-/(E)-anisaldehyde-based oxime ester compounds were designed and synthesized by using anisaldehyde as starting material. Structural characterization of the target compounds was carried out by NMR, FT-IR, ESI-MS, and elemental analysis. Their herbicidal and antifungal activities were preliminarily tested. As a result, at 50 μg/mL, compound (E)- 5b exhibited excellent to good inhibition rates of 92.3 %, 79.2 %, and 73.9 %, against Rhizoctonia solani, Fusarium oxysporum f. sp. cucumerinum, and Bipolaris maydis, respectively, better than or comparable to that of the positive control chlorothalonil. In addition, at 100 μg/mL, compounds (E)- 5b , (E)- 5f , (Z)- 5f and (E)- 5d exhibited excellent to good inhibition rates of 85.8 %, 82.9 %, 78.6 % and 64.2 %, respectively, against the root-growth of rape (B. campestris), much better than that of the positive control flumioxazin. The bioassay result also showed that the synthesized compounds had obvious differences in antifungal and herbicidal activities between (Z)- and (E)-isomers. Preliminary structure–activity relationship was also discussed by theoretical calculation.  相似文献   

20.
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