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1.
Felix Feistel Christian Paetz Riya C. Menezes Daniel Veit Bernd Schneider 《Journal of chemical ecology》2018,44(5):497-509
Salicortin is a phenolic glucoside produced in Salicaceae as a chemical defense against herbivory. The specialist lepidopteran herbivorous larvae of Cerura vinula are able to overcome this defense. We examined the main frass constituents of C. vinula fed on Populus nigra leaves, and identified 11 quinic acid derivatives with benzoate and/or salicylate substitution. We asked whether the compounds are a result of salicortin breakdown and sought answers by carrying out feeding experiments with highly 13C-enriched salicortin. Using HRMS and NMR analyses, we were able to confirm that salicortin metabolism in C. vinula proceeds through deglucosylation and ester hydrolysis, after which saligenin is oxidatively transformed into salicylic acid and, eventually, conjugated to quinic acid. To the best of our knowledge, this is the first report of a detoxification pathway based on conjugation with quinic acid. 相似文献
2.
A. A. Dmitrienko 《Coke and Chemistry》2018,61(5):165-170
The possibility of express determination of the characteristics V IR daf , Ro, IR, yIR, ΣLCIR, and A IR d used in the ranking of coal on the basis of IR spectroscopy is assessed for a specific example: Kuznetsk coals of different maceral composition and metamorphic development. The IR characteristics are compared with values obtained by standard methods (Vdaf, Ro, r, y, ΣLC, and Ad). 相似文献
3.
High Arachidonic Acid Levels in the Tissues of Herbivorous Fish Species (<Emphasis Type="Italic">Siganus fuscescens,Calotomus japonicus</Emphasis> and <Emphasis Type="Italic">Kyphosus bigibbus</Emphasis>)
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Asada Jiarpinijnun Soottawat Benjakul Akasith Pornphatdetaudom Junichiro Shibata Emiko Okazaki Kazufumi Osako 《Lipids》2017,52(4):363-373
The lipid and fatty acid compositions in the various organs (muscle, liver, other viscera) and stomach contents of three common herbivorous fish species in Japan, Siganus fuscescens, Calotomus japonicus and Kyphosus bigibbus, were examined to explore the stable 20:4n-6 (arachidonic acid, ARA) sources. Triacylglycerol (TAG), phosphatidylethanolamine (PtdEtn), and phosphatidylcholine (PtdCho) were the dominant lipid classes, while the major FA contents were 16:0, 18:1n-9, 16:1n-7, 14:0, 18:0, 18:1n-7, and some PUFA, including ARA, 20:5n-3 (eicosapentaenoic acid, EPA), 22:5n-3 (docosapentaenoic acid, DPA), and 22:6n-3 (docosahexaenoic acid, DHA). The amounts of these fatty acids were varied among species and their lipid classes. Phospholipids contained higher levels of PUFA than TAG. However, ARA in both phospholipids and TAG was markedly present in the muscle and viscera of all specimens, particularly in C. japonicus and K. bigibbus. Moreover, their ARA levels were higher than the levels of DHA and EPA. The observed high ARA level is unusual in marine fish and might be characteristic of herbivorous fish. Furthermore, ARA was the dominant PUFA in the stomach contents of the three species, suggesting that the high ARA level originated from their food sources. The above indicates that these three herbivorous fishes are ARA-rich marine foods and have potential utilization as stable ARA resources. 相似文献
4.
Identification of Crepenynic Acid in the Seed Oil of <Emphasis Type="Italic">Atractylodes lancea</Emphasis> and <Emphasis Type="Italic">A. macrocephala</Emphasis>
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Atractylodes rhizome is widely used in traditional Chinese herbal medicine. Although the chemical composition of the root has been studied in detail, the oil content and fatty acid composition of the seeds of Atractylodes species have not been reported. Fatty acyl composition of seeds from Atractylodes lancea and A. macrocephala was determined by gas chromatography and mass spectrometry of fatty acid methyl esters and 3-pyridylcarbinol esters. The predominant fatty acid in the seeds of both species was linolenic acid, but the unusual acetylenic fatty acid, crepenynic acid (cis-9-octadecen-12-ynoic acid), was also observed at levels of 18% in A. lancea and 13–15% in A. macrocephala. Fatty acid content was 24% for the samples of A. lancea and 16–17% for samples from A. macrocephala. sn-1,3 regioselective lipase digestion of seed lipids revealed that crepenynic acid was absent from the sn-2 position of the seed triacylglycerol. Crepenynic acid was also found in the seed oil of Jurinea mollis at 24% and was not present in the sn-2 position of the TAG. A contrasting distribution of crepenynic acid was found in the oil of Crepis rubra, suggesting differences in crepenynic acid synthesis or TAG assembly between these species. 相似文献
5.
Geneviève Chiapusio Vincent E. J. Jassey Floriant Bellvert Gilles Comte Leslie A. Weston Frederic Delarue Alexandre Buttler Marie Laure Toussaint Philippe Binet 《Journal of chemical ecology》2018,44(12):1146-1157
Sphagnum mosses mediate long-term carbon accumulation in peatlands. Given their functional role as keystone species, it is important to consider their responses to ecological gradients and environmental changes through the production of phenolics. We compared the extent to which Sphagnum phenolic production was dependent on species, microhabitats and season, and how surrounding dwarf shrubs responded to Sphagnum phenolics. We evaluated the phenolic profiles of aqueous extracts of Sphagnum fallax and Sphagnum magellanicum over a 6-month period in two microhabitats (wet lawns versus dry hummocks) in a French peatland. Phenolic profiles of water-soluble extracts were measured by UHPLC-QTOF-MS. Andromeda polifolia mycorrhizal colonization was quantified by assessing the intensity of global root cortex colonization. Phenolic profiles of both Sphagnum mosses were species-, season- and microhabitat- dependant. Sphagnum-derived acids were the phenolics mostly recovered; relative quantities were 2.5-fold higher in S. fallax than in S. magellanicum. Microtopography and vascular plant cover strongly influenced phenolic profiles, especially for minor metabolites present in low abundance. Higher mycorrhizal colonization of A. polifolia was found in lawns as compared to hummocks. Mycorrhizal abundance, in contrast to environmental parameters, was correlated with production of minor phenolics in S. fallax. Our results highlight the close interaction between mycorrhizae such as those colonizing A. polifolia and the release of Sphagnum phenolic metabolites and suggest that Sphagnum-derived acids and minor phenolics play different roles in this interaction. This work provides new insight into the ecological role of Sphagnum phenolics by proposing a strong association with mycorrhizal colonization of shrubs. 相似文献
6.
The density d at a temperature of 25°C is measured by the hydrostatic weighing method, the Vickers microhardness H V is determined, and the fluctuation free volume fraction f g is calculated for glasses in the SrO-B2O3-SiO2 system with a constant strontium oxide content in the range from 35 to 45 mol %. It is demonstrated that the quantities H V and f g decrease and the density d increases with an increase in the SrO content. 相似文献
7.
In moths, sexual behavior combines female sex pheromone production and calling behavior. The normal functioning of these periodic events requires an intact nervous system. Neurotoxic insecticide residues in the agroecosystem could impact the normal functioning of pheromone communication through alteration of the nervous system. In this study we assess whether sublethal concentrations of the neonicotinoid insecticide thiacloprid, that competitively modulates nicotinic acetylcholine receptors at the dendrite, affect pheromone production and calling behavior in adults of three economically important tortricid moth pests; Cydia pomonella (L.), Grapholita molesta (Busck), and Lobesia botrana (Denis & Schiffermüller). Thiacloprid significantly reduced the amount of calling in C. pomonella females at LC0.001 (a lethal concentration that kills only 1 in 105 individuals), and altered its calling period at LC1, and in both cases the effect was dose-dependent. In the other two species the effect was similar but started at higher LCs, and the effect was relatively small in L. botrana. Pheromone production was altered only in C. pomonella, with a reduction of the major compound, codlemone, and one minor component, starting at LC10. Since sex pheromones and neonicotinoids are used together in the management of these three species, our results could have implications regarding the interaction between these two pest control methods. 相似文献
8.
A. L. Amrutha Kala 《Journal of the American Oil Chemists' Society》2012,89(10):1813-1821
The fatty acid composition of 27 samples of commercial hydrogenated vegetable oils and 23 samples of refined oils such as sunflower oil, rice bran oil, soybean oil and RBD palmolein marketed in India were analyzed. Total cis, trans unsaturated fatty acids (TFA) and saturated fatty acids (SFA) were determined. Out of the 27 hydrogenated fats, 11 % had TFA about 1 % where as 11 % had more than 5 % TFA with an average value of about 13.1 %. The 18:1 trans isomers, elaidic acid was the major trans contributor found to have an average value of about 10.8 % among the fats. The unsaturated fatty acids like cis-oleic acid, linoleic acid and α-linolenic acid were in the range of 21.8–40.2, 1.9–12.2, 0.0–0.7 % respectively. Out of the samples, eight fats had fatty acid profiles of low TFA (less than 10 %) and high polyunsaturated fatty acids (PUFA) such as linoleic and α-linolenic acid. They had a maximum TFA content of 7.3 % and PUFA of 11.7 %. Among the samples of refined oils, rice bran oil (5.8 %) and sunflower oil (4.4 %) had the maximum TFA content. RBD palmolein and rice bran oils had maximum saturated fatty acids content of 45.1 and 24.4 % respectively. RBD palmolein had a high monounsaturated fatty acids (MUFA) content of about 43.4 %, sunflower oil had a high linoleic acid content of about 56.1 % and soybean oil had a high α-linolenic acid content of about 5.3 %. 相似文献
9.
The influence of the chemical nature of the local environment of Eu3+ ions on the parameters of luminescence of these centers in glasses of the (BaGeO3)1 ? x ? y (Al2O3) x (0.45CaF2 · 0.55MgF2) y (x = 0.25, y = 0; x = 0.17, y = 0.17; x = 0.15, y = 0.22; x = 0.07, y = 37.00; x = 0, y = 0.45) system is investigated. The oxidation state of europium atoms and the degree of homogeneity of their local environment in the glasses are determined using 151Eu Mössbauer spectroscopy. 相似文献
10.
Ismat Bibi Aneela Sultan Shagufta Kamal Shazia Nouren Yusra Safa Kashif Jalani Misbah Sultan Sadia Atta Fariha Rehman 《Korean Journal of Chemical Engineering》2017,34(2):392-399
The current research project has been devoted to isolating new low cost and eco-friendly phenolic compounds from fruit seeds, peels and vegetables to reduce the atmospheric pollution. Natural phenolic compounds were extracted from different fruit seeds and agriculture waste: P. armeniaca, P. persica, P. domestica and Triticum aesativum. The total phenolic content was quantified, and the maximum value (1 mL extract having 1,933 μg) was found in P. armeniaca seed extract. Phytochemical screening showed that P. armeniaca seeds contain higher amount of alkaloid, tannins, saponins and flavonoid. P. armeniaca seeds enhanced the biotransformation of reactive yellow dye up to 69.89% with maximum laccase (322.45 IU/mL) production. Biodegradation of reactive yellow was only 23.34% without natural redox mediator at sixth day of incubation. Use of P. armeniaca seed stimulators resulted in maximum laccase activity (894.4 IU/mL) with 99.5% rate of removal. UV-Vis, HPLC & FTIR analysis confirmed the transformation of parent dye into various new products. Phytotoxicity study indicated 0% germination index of Avena sativa seeds with reactive yellow, whereas 83% germination index having 100% seed germination while 83% root elongation with treated sample. Thus, the study revealed that the natural phenolic compounds could serve as high potential redox mediators for enhanced laccase-mediated decolorization of reactive yellow dye. 相似文献
11.
It is difficult to research on the surface structure of amorphous phase in fly ash during leaching reaction due to crystalline phase and complex structure. In the present work, in order to reveal the effects of leaching reaction on the surface structure of amorphous phase in fly ash, the modelling CaO-Fe2O3-Al2O3-SiO2 glass was prepared by the traditional melting methods. The leaching reaction of CaO-Fe2O3-Al2O3-SiO2 glass with 7.5 M KOH was investigated by spectroscopy, spectrophotometer and wet chemical method. The results show that the content of Q 1, Q 2, Q 3 and Q 4 of glass without corrosion was 4.21, 9.51, 23.03 and 52.55%, respectively, which shows that the network polymerization of glass is compact. The leaching reaction of glass can be described by the following equation: dS/dt = k/(r + S 0). Leaching in KOH for various times induces the content of Q 4 and Q 1 to be decreased, and Q 2 and Q 3 increased, resulted in the depolymerization of network and the surface glass dissolved in alkaline solution to form a gel phase. In stage one of leaching reaction, the rate of iron ion leached from glass surface was slow, which resulted in the small slope of straight-line relationship of leaching curve. In the following stage, the leaching rate of iron ion increased with the prolongation of time. 相似文献
12.
Ghoshna Jyoti Amit Keshav Jayapal Anandkumar 《Korean Journal of Chemical Engineering》2017,34(6):1661-1668
Esterification of acrylic acid with ethanol was carried out using an in-situ reactor with an integrated pervaporation assembly (IPAE) made of polyvinyl alcohol (PVA) membrane and was compared with a non-integrated (NIE) system. Effect of reaction temperature (T r ), catalyst loading (C C ), molar ratios of reactants (MR) and ratio of effective membrane area to unit volume of reaction mixture (S/V o ) on kinetics of esterification reaction were studied. Conversions achieved in IPAE were found to be distinctly higher than the NIE. The highest conversion of acrylic acid was obtained as 83.3% at T r =60 °C, M R =3 : 1, C C =2% and S/V o =14.1 m?1. Equilibrium conversion of acrylic acid in NIE was obtained as 55.1% at 60 °C, 1 : 1 in 7 h, while using IPAE conversion enhances to 67.6%. Esterification of acrylic acid and ethanol with presently studied operating parameters provides a new approach to existing literature reported esterification-pervaporation system. 相似文献
13.
Derivatives of 2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropanecarboxylic acid (chrysanthemic acid) are classic natural pyrethroids discovered in pyrethrum plants and show insecticidal activity. Chrysanthemic acid, with two asymmetric carbons, has four possible stereoisomers, and most natural pyrethroids have the (1R,3R)-trans configuration. Interestingly, chrysanthemic acid–related structures are also found in insect sex pheromones; carboxylic esters of (1R,3R)-trans-(2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropyl)methanol (chrysanthemyl alcohol) have been reported from two mealybug species. In the present study, another ester of chrysanthemyl alcohol was discovered from the striped mealybug, Ferrisia virgata (Cockerell), as its pheromone. By means of gas chromatography–mass spectrometry, nuclear magnetic resonance spectrometry, and high-performance liquid chromatography analyses using a chiral stationary phase column and authentic standards, the pheromone was identified as (1S,3R)-(?)-cis-chrysanthemyl tiglate. The (1S,3R)-enantiomer strongly attracted adult males in a greenhouse trapping bioassay, whereas the other enantiomers showed only weak activity. The cis configuration of the chrysanthemic acid–related structure appears to be relatively scarce in nature, and this is the first example reported from arthropods. 相似文献
14.
R. S. Bubnova J. E. Anderson M. G. Krzhizhanovskaya S. K. Filatov 《Glass Physics and Chemistry》2010,36(3):369-375
Anhydrous ammonium pentaborate NH4B5O8 has been synthesized by thermal dehydration of larderellite NH4[B5O7(OH)2] · H2O at a temperature of 290°C for 7 h. The crystal structure has been determined from the X-ray powder diffraction data: a = 7.58667(5) Å, b = 12.00354(8) Å, c = 14.71199(8) Å, R p = 6.23, R wp = 7.98, R B = 12.7, R F = 8.95, and β-KB5O8 structure type. The double interpenetrating framework is formed by pentaborate groups, each consisting of a boron-oxygen tetrahedron and four triangles, in which all oxygen atoms are bridging. The thermal behavior of the NH4B5O8 compound has been investigated using thermal X-ray diffraction. As for other pentaborates of this type, the thermal expansion of the NH4B5O8 compound is anisotropic and reaches a maximum along the a axis. The thermal expansion coefficients are as follows: α a = 39 × 10?6, α b = 6 × 10?6, α c = 20 × 10?6, and α V = 65 × 10?6 °C?1. 相似文献
15.
The crystal structure of a low-temperature modification of the Li12Zn4(P2O7)5 compound has been determined by full-profile analysis from the X-ray powder diffraction data. The compound crystallizes in the monoclinic crystal system (a = 5.130(1) Å, b = 13.454(1) Å, c = 8.205(1) Å, β = 90.36(1)°, space group P21/n, Z = 4) and has a framework structure in which the zinc and lithium atoms statistically occupy equivalent positions. 相似文献
16.
E. P. Naiden V. A. Zhuravlev V. I. Itin R. V. Minin V. I. Suslyaev O. A. Dotsenko 《International Journal of Self-Propagating High-Temperature Synthesis》2016,25(4):203-209
Static and dynamic magnetic properties of SHS-produced BaFe12–2x (Co х Ti х )O19 (х = 1.0, 1.1, 1.2) and SrFe12–2y (Co y Ti y )O19 (0 ≤ y ≤ 1.0) hexaferrites were characterized by magnetization and FMR measurements. Dynamic properties of SrFe12–2y (Co y Ti y )O19 hexaferrites were rationalized in terms of not only magnetic anisotropy but also the anisotropy of magnetomechanical ratio. SHS-produced ferrites can be recommended for designing radar-absorbent coatings and other SHF devices operating in the range 20–50 GHz. 相似文献
17.
Ikkei Shikano Qinjian Pan Kelli Hoover Gary W. Felton 《Journal of chemical ecology》2018,44(10):947-956
Plants can influence the effectiveness of microbial insecticides through numerous mechanisms. One of these mechanisms is the oxidation of plant phenolics by plant enzymes, such as polyphenol oxidases (PPO) and peroxidases (POD). These reactions generate a variety of products and intermediates that play important roles in resistance against herbivores. Oxidation of the catecholic phenolic compound chlorogenic acid by PPO enhances the lethality of the insect-killing bacterial pathogen, Bacillus thuringiensis var. kurstaki (Bt) to the polyphagous caterpillar, Helicoverpa zea. Since herbivore feeding damage often triggers the induction of higher activities of oxidative enzymes in plant tissues, here we hypothesized that the induction of plant defenses would enhance the lethality of Bt on those plants. We found that the lethality of a commercial formulation of Bt (Dipel® PRO DF) on tomato plants was higher if it was applied to plants that were induced by H. zea feeding or induced by the phytohormone jasmonic acid. Higher proportions of H. zea larvae killed by Bt were strongly correlated with higher levels of PPO activity in the leaflet tissue. Higher POD activity was only weakly associated with higher levels of Bt-induced mortality. While plant-mediated variation in entomopathogen lethality is well known, our findings demonstrate that plants can induce defensive responses that work in concert with a microbial insecticide/entomopathogen to protect against insect herbivores. 相似文献
18.
A cathode material for lithium-ion batteries–LiNi1/3Co1/3Mn1/3O2–was prepared by solution combustion synthesis and characterized by XRD, SEM, and galvanostatic charge/discharge cycling. The sample calcined at 950°C for 10 h showed best charge/discharge performance. An initial discharge capacity (C) of 150.5 mA h g–1 retained 95.7% of its value after 75 charge/discharge cycles at Ic = 14 mA g–1 (0.2C rate), Id = 70 mA g–1 (0.5C rate). 相似文献
19.
Karen J. Marsh Wufeng Zhou Hannah J. Wigley William J. Foley 《Journal of chemical ecology》2017,43(4):411-421
Insect folivores can cause extensive damage to plants. However, different plant species, and even individuals within species, can differ in their susceptibility to insect attack. Polyphenols that readily oxidize have recently gained attention as potential defenses against insect folivores. We tested the hypothesis that variation in oxidizable phenolic concentrations in Eucalyptus foliage influences feeding and survival of Paropsis atomaria (Eucalyptus leaf beetle) larvae. First we demonstrated that oxidizable phenolic concentrations vary both within and between Eucalyptus species, ranging from 0 to 61 mg.g?1 DM (0 to 81% of total phenolics), in 175 samples representing 13 Eucalyptus species. Foliage from six individuals from each of ten species of Eucalyptus were then offered to batches of newly hatched P. atomaria larvae, and feeding, instar progression and mortality of the first and second instar larvae were recorded. Although feeding and survival parameters differed dramatically between individual plants, they were not influenced by the oxidizable phenolic concentration of leaves, suggesting that P. atomaria larvae may have effective mechanisms to deal with oxidizable phenolics. Larvae feeding on plants with higher nitrogen (N) concentrations had higher survival rates and reached third instar earlier, but N concentrations did not explain most of the variation in feeding and survival. The cause of variation in eucalypt herbivory by P. atomaria larvae is therefore still unknown, although oxidizable phenolics could potentially defend eucalypt foliage against other insect herbivores. 相似文献
20.
David L. Compton Fred J. Eller Joseph A. Laszlo Kervin O. Evans 《Journal of the American Oil Chemists' Society》2012,89(8):1529-1536
The fatty acid moiety of 2-monoacyl-sn-glycerol (2-MAG) undergoes spontaneous acyl migration to the sn-1(3) position, resulting in a thermodynamic equilibrium of approximately 1:9 of 2-MAG to 1(3)-monoacyl-sn-glycerol (1-MAG). Spontaneous acyl migration is an impediment to synthesizing and isolating specific 2-MAG for use as intermediates in the synthesis of structured triacylglycerols. 2-Monooleoyl-sn-glycerol was synthesized by the enzymatic ethanolysis of triolein and isolated by liquid CO2 extraction. The resultant MAG, diacylglycerol, and fatty acid ethyl esters were quantified by 1H NMR and supercritical fluid chromatography. The low polarity of the CO2 and mild extraction temperature (25 °C) resulted in very low spontaneous acyl migration rates, allowing the MAG to be isolated in 80% yield and in a very high 2-MAG:1-MAG ratios of ≥93 mol%. 相似文献