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1.
Reaction selectivities were determined in multicompetitive reactions mediated by Rhizomucor miehei (RM) lipase at water activity of 0.19 in hexane. Saturated FA (C4–C18 even chain) and oleic acid (C18∶1) were reacted with
a single alcohol, glycerol, or α-or β-MAG containing C4, C10, C16, or C18∶1 individually as alcohol cosubstrate. Similar patterns
of broad FA selectivity toward C8–C18 FA were generally observed for esterification into specific acylglycerol (AG) pools
with the different α/β-CX-MAG cosubstrates. Exceptions were enrichment of C18 in the MAG pool with α-C16-MAG substrate, and
a general suppression of C4/C6 FA reactivity and a specific discrimination toward >C8 FA incorporation into the TAG pool,
both for reactions with α-C10- and α-C16-MAG. RM lipase selectivity toward MAG was in descending order: β-C18∶1-MAG>α/β-C4-MAG∼β-C10-MAG∼β-C16-MAG>α-C18∶1-MAG
>α-C10-MAG∼α-C16-MAG. Selectivity in channeling CX of the original CX-MAG substrates into higher AG species was in descending
order: α-C10-MAG∼α-C16-MAG>β-C10-MAGβ-C16-MAG>α-C18∶1-MAG>β-C18∶1-MAG∼ α/β-C4-MAG. Aside from their characteristic FA selectivity,
Burkholderia cepacia (PS-30) and RM lipases behaved similarly in terms of MAG selectivity as well as a general conservation of FA selectivity
throughout the sequential steps of TAG assembly from FA and glycerol for processes designed to yield specifically structured
TAG. 相似文献
2.
Kirsten A. Leiss Young H. Choi Ibrahim B. Abdel-Farid Robert Verpoorte Peter G. L. Klinkhamer 《Journal of chemical ecology》2009,35(2):219-229
Western flower thrips (Frankliniella occidentalis) has become a key insect pest of agricultural and horticultural crops worldwide. Little is known about host plant resistance
to thrips. In this study, we investigated thrips resistance in F
2 hybrids of Senecio jacobaea and Senecio aquaticus. We identified thrips-resistant hybrids applying three different bioassays. Subsequently, we compared the metabolomic profiles
of these hybrids applying nuclear magnetic resonance spectroscopy (NMR). The new developments of NMR facilitate a wide range
coverage of the metabolome. This makes NMR especially suitable if there is no a priori knowledge of the compounds related
to herbivore resistance and allows a holistic approach analyzing different chemical compounds simultaneously. We show that
the metabolomes of thrips-resistant and -susceptible hybrids differed considerably. Thrips-resistant hybrids contained higher
amounts of the pyrrolizidine alkaloids (PA), jacobine, and jaconine, especially in younger leaves. Also, a flavanoid, kaempferol
glucoside, accumulated in the resistant plants. Both PAs and kaempferol are known for their inhibitory effect on herbivores.
In resistant and susceptible F
2 hybrids, young leaves showed less thrips damage than old leaves. Consistent with the optimal plant defense theory, young
leaves contained increased levels of primary metabolites such as sucrose, raffinose, and stachyose, but also accumulated jacaranone
as a secondary plant defense compound. Our results prove NMR as a promising tool to identify different metabolites involved
in herbivore resistance. It constitutes a significant advance in the study of plant–insect relationships, providing key information
on the implementation of herbivore resistance breeding strategies in plants.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
3.
Abdalbasit Adam Mariod Kawthar Mahmoud Aseel Ali Abdalgadir Mustafa Siddig Ibrahim Abdel-Wahab 《Journal of the American Oil Chemists' Society》2009,86(8):749-755
The oil and meal from Monechma ciliatum (black mahlab) and Prunus mahaleb (white mahlab) seeds were characterized for their physicochemical properties. The oil content was found to be 30.95 and 13.15%
in white and black mahlab seeds, respectively. The refractive indices of white mahlab oil (WMO) and black mahlab oil (BMO)
were 1.475 and 1.470, and specific gravities were 0.8511 and 0.8167 g/cm3, respectively. Saponification values were 184.23 and 180.3 mg KOH/g, peroxide values were 2.54 and 4.43 meq/kg, and unsaponifiable
matter was 0.92 and 0.66%, respectively. The major fatty acids were palmitic 4.5%, stearic 16.0%, oleic 47.3%, and linoleic
31.4% in BMO, while in WMO they were palmitic 5.7%, oleic 45.0%, and linoleic acid 47.0%. A moderate amount of tocopherols
were found at 45.2 and 28.5 mg/100 g in BMO and WMO, respectively. Protein content was found to be 21% in black and 28% in
white mahlab seeds. The total amount of amino acids in black and white mahlab seeds was found to be 783.3 and 1,223.2 mg/g N,
respectively. The concentration (on ppm dry-weight basis) of major elements (Ca, K, and Mg) and of minor elements (Al, Pb
Ni, Mn, Cu, Cr, Co, and Fe) was also determined in the meals. 相似文献
4.
Dhanapalan Karthikeyan Nachiappan Lingappan Bommasamudram Sivasankar 《Korean Journal of Chemical Engineering》2008,25(5):987-997
Bifunctional catalysts containing (0.1–0.5 wt%) Nickel and 0.1 wt% of Pd supported on H-β zeolite were synthesized by incipient wetness impregnation method and characterized by XRD, TEM, XPS, TPD and TPR techniques.
The catalytic activity of Ni containing and Ni free Pd/H-β Catalysts was studied, and it was found that Ni up to a threshold value (0.3 wt% on β) produced increased the n-decane conversion and isomerization selectivity. When Ni content exceeds the threshold value, the
conversion increases but isomerized products decrease. Moreover, Ni containing Pd/H-β showed increased sustainability and favored the protonated cyclopropane (PCP) intermediate mechanism in n-decane isomerization.
The catalyst containing 0.3 wt% Ni 0.1 wt% Pd is adjudged as one performing better than other catalysts studied because of
the isomerized mixture from it shows better octane number. 相似文献
5.
We tested differences in female pheromone production and male response in three species of the genus Adoxophyes in Korea. Females of all three species produced mixtures of (Z)-9-tetradecenyl acetate (Z9–14:OAc) and (Z)-11-tetradecenyl acetate (Z11–14:OAc) as major components but in quite different ratios. The ratio of Z9–14:OAc and Z11–14:OAc in pheromone gland extracts was estimated to be ca. 100:200 for Adoxophyes honmai, 100:25 for Adoxophyes orana, and 100:4,000 for Adoxophyes sp. Field tests showed that males of each species were preferentially attracted to the two-component blends of Z9–14:OAc and Z11–14:OAc mimicking the blends found in pheromone gland extracts of conspecific females. The effects of minor components identified
in gland extracts on trap catches varied with species. Addition of 10-methyldodecyl acetate (10me-12:OAc) or (E)-11-tetradecenyl acetate (E11–14:OAc) to the binary blend of Z9–14:OAc and Z11–14:OAc significantly increased captures of A. honmai males, whereas E11–14:OAc exhibited a strongly antagonistic effect on catches of Adoxophyes sp. males. Moreover, (Z)-9-tetradecen-1-ol (Z9–14:OH) or (Z)-11-tetradecen-1-ol (Z11–14:OH) added to the binary blends increased attraction of male A. orana but not A. honmai and Adoxophyes sp. males, suggesting that these minor components, in addition to the relative ratios of the two major components, play an
important role in reproductive isolation between Adoxophyes species in the southern and midwestern Korea where these species occur sympatrically. 相似文献
6.
Hong-Wei Wang In Hae Kim Chang-Su Park Jae-Hwa Lee 《Korean Journal of Chemical Engineering》2008,25(4):801-803
α-amylase from Bacillus licheniformis was successfully immobilized on developed support, which was prepared by coating a chitosan-casein film on silica, at 20
°C, pH 6.0 for 5 hr with microbial transglutaminase (MTG) as the cross-linking factor. The optimal support was obtained when
1% chitosan and 1% casein were used in the coating mixture. The optimal condition for immobilization catalyzed by MTG was
confined to be at MTG concentration of 15 U/mL, pH 6.0, reacting for 6 hr at 20 °C. The highest specific activity of immobilized
α-amylase was achieved as 236 U/g. After immobilization, the obtained enzyme showed broader pH profile and maintained more
than 70% of the original activity after 20 reuses. 相似文献
7.
Maleeha Manzoor Farooq Anwar Tahira Iqbal M. I. Bhanger 《Journal of the American Oil Chemists' Society》2007,84(5):413-419
The present work reports the characterization and comparison of Moringa concanensis seed oil from Tharparkar (a drought hit area), Pakistan. The hexane-extracted oil content of M. concanensis seeds ranged from 37.56 to 40.06% (average 38.82%). Protein, fiber, moisture and ash contents were found to be 30.07, 6.00,
5.88 and 9.00%, respectively. The extracted oil exhibited an iodine value of 67.00; a refractive index (40 °C) of 1.4648;
its density (24 °C) was 0.8660 mg mL−1; the saponification value (mg of KOH g−1 of oil) was 179.00; unsaponifiable matter 0.78%; color (1 in. cell) 1.90R + 19.00Y; and acidity (% as oleic acid) 0.34%.
Tocopherols (α, γ, and δ) in the oil accounted for 72.11, 9.26 and 33.87 mg kg−1, respectively. Specific extinctions at 232 and 270 nm were 3.17 and 0.65, respectively. The peroxide and p-anisidine values of the oil were found to be 1.75 and 1.84 meq kg−1, respectively. The induction periods (Rancimat, 20 L h−1, 120 °C) of the crude oil was 10.81 h and reduced to 8.90 h after degumming. The M.
concanensis oil was found to contain high levels of oleic acid (up to 68.00%) followed by palmitic, stearic, behenic, and arachidic acids
up to levels of 11.04, 3.58, 3.44 and 7.09%, respectively. The results of the present analytical study, compared with those
for other Moringa species and different vegetable oils, showed M. concanensis to be a potentially valuable non-conventional seed crop for high quality oil. 相似文献
8.
The effects of key parameters on the preparation and regeneration of protoplast from the β-carotene-producing fungus Blakeslea trispora were discussed in this paper, including the combination of various enzymes, mycelial age, digesting time and temperature,
pH value, osmotic stabilizers, pretreatment, culture medium and culture method. Under the condition of mixed enzymes in osmotic
stabilizer (0.6 M NaCl) combined with 2% lysozyme, 3% cellulase and 3% snailase, the highest protoplast yield, as high as
7.48×106 protoplasts/mL, was obtained when mycelial age was 60 h at pH 5.0–6.0 with digesting for 14–16 h at 28 °C. After
purification of the obtained protoplasts, they were regenerated in PDA regenerative medium using bilayer plate culture method.
To validate the usability of the protoplasts, a novel plasmid with green fluorescent protein (GFP) was used in transformation
for easy visual observation. The results showed that the protoplasts prepared by the optimized method were active and applicable
in further gene manipulation experiments.
This work was presented at 13
th
YABEC symposium held at Seoul, Korea, October 20–22, 2007. 相似文献
9.
The trans fatty acid (TFA) patterns in the fats of ruminant meat and dairy products differ from those found in other (processed) fats.
We have evaluated different TFA isomers in human breast milk as an indicator of dietary intake of ruminant and dairy fats
of different origins. Breast milk samples were collected 1 month postpartum from 310 mothers participating in the KOALA Birth
Cohort Study (The Netherlands). The study participants had different lifestyles and consumed different amounts of dairy products.
Fatty acid methyl esters were determined by GC-FID and the data were evaluated by principal component analysis (PCA), ANOVA/Post
Hoc test and linear regression analysis. The two major principal components were (1) 18:1 trans-isomers and (2) markers of dairy fat including 15:0, 17:0, 11(trans)18:1 and 9(cis),11(trans)18:2 (CLA). Despite similar total TFA values, the 9(trans)18:1/11(trans)18:1-ratio and the 10(trans)18:1/11(trans)18:1-ratio were significantly lower in milk from mothers with high dairy fat intake (40–76 g/day: 0.91 ± 0.48, P < 0.05) compared to low dairy fat intake (0–10 g/day: 1.59 ± 0.48), and lower with strict organic meat and dairy use (>90%
organic: 0.92 ± 0.46, P < 0.05) compared to conventional origin of meat and dairy (1.40 ± 0.61). Similar results were obtained for the 10(trans)18:1/11(trans)18:1-ratio. We conclude that both ratios are indicators of different intake of TFA from ruminant and dairy origin relative
to other (including industrial) sources. 相似文献
10.
Aliou Faye Saidou Sall Jean-Luc Chotte Didier Lesueur 《Nutrient Cycling in Agroecosystems》2007,79(1):35-44
Acacia nilotica var. tomentosa trees from the Diarra protected forest located in the Senegal River valley were identified for the assessment of both biological
nitrogen fixation, using the natural abundance method, and soil bio-functioning parameters (nodulation, root biomass, total
microbial biomass, and potential N mineralization). The presence and the genetic diversity of indigenous rhizobia nodulating
A. nilotica var. tomentosa was also investigated, taking into account distance from the trunk (0, 1, 2, and 3 m) and depth (0–25, 25–50, and 50–75 cm).
Surprisingly, no nodules on the trees root systems were found, whereas under laboratory conditions the presence of indigenous
rhizobia nodulating A. nilotica var. tomentosa was demonstrated in the analyzed soils (90% of the nodules harvested on the trapped plants were occupied by the same Inter-Genic
Spacer (IGS) group, IGS1). There was no significant influence of trees and/or depth on total microbial biomass and potentials
of nitrogen mineralization. Some assumptions were formulated on the possible combined effect of flooding, which usually occurs
annually during 4–7 months, and the clayey soils in the Diara forests. Although a deeply natural nodulation of A. nilotica var. tomentosa trees by indigenous rhizobia is not excluded, but it still remains to be demonstrated. 相似文献
11.
Francisco López-Carrasquero Giuseppe Giammanco Angélica Díaz Johanna Dávila Carlos Torres Estrella Laredo 《Polymer Bulletin》2009,63(1):69-78
A series of comb like poly(p-n-alkylstyrene)s with linear alkyl groups, containing even numbers of carbon atoms from 12 up to 22 were synthesized by radical
polymerization and characterized by FTIR, 1H NMR, TGA, TVA DSC, and WAXS. All polymers were obtained in good yields and were soluble in organic solvents as chloroform,
dichloromethane or tetrahydrofuran and insoluble in methanol; they are stable up to temperatures near 300 °C. On the other
hand, the alkylic side chains of all series are able to crystallize in a paraffinic phase in which the melting temperature
and enthalpy increase with the methylene number of the n-alkyl chain. 相似文献
12.
W. M. N. Ratnayake C. Gagnon L. Dumais W. Lillycrop L. Wong M. Meleta P. Calway 《Journal of the American Oil Chemists' Society》2007,84(9):817-825
Dietary trans fatty acids (TFA) are of major concern because of their adverse effects on blood lipid levels and coronary heart disease.
In Canada, margarines were significant sources of TFA during the 1980s and 1990s. However, this is expected to change with
increased public awareness over their adverse health effects and the introduction of new legislature to include TFA content
on the Nutritional Facts table of food labels. In this study, the TFA content of the top-selling 29 Canadian margarines, which
represented 96.3% of the market share, was determined by capillary gas-liquid chromatography in order to assess the influence
of regulatory development during the 3-year transition period between the announcement of new food labelling regulations in
Canada that require mandatory declaration of the trans fat content in most pre-packaged foods in January 2003 and its enforcement on 12 December 2005. The 29 margarines included
15 tub margarines made from non-hydrogenated vegetable oils (NHVO-tub margarines), 11 tub margarines made from partially hydrogenated
vegetable oils (PHVO-tub margarines) and three print margarines, which were also made from partially hydrogenated vegetable
oils (PHVO-print margarines). The 15 NHVO tub-margarines accounted for 71% of the total margarine market share and generally
contained less than 2% TFA (mean value 0.9 ± 0.3% of total fatty acids). The mean total TFA contents of PHVO-tub margarines
and PHVO-print margarines, were 20.0 ± 4.5% and 39.6 ± 3.5%, and their market shares were 19.3 and 6.0%, respectively. Although
during the last 10 years, increasing number of soft tub margarines that contained very little trans fats have been made available in Canada, the PHVO-tub- and -print margarines still contain high levels of trans fats similar to those margarines that were sold in the 1990s. The market share data suggest that the margarines prepared
using NHVO and containing almost no TFA were preferred by Canadians over those margarines prepared using PHVO, even before
the mandatory declaration of TFA content came into effect on 12 December 2005. 相似文献
13.
TPD studies of n-hexane and n-heptane from NaX, Y and ZSM-5 (Na+ or H+ exchanged) in the experimental system with a TCD detector were performed, using pure He or He/n-alkane mixture as a carrier gas. The TPD profiles with one desorption peak for Y and two peaks for ZSM-5, measured using
He/hydrocarbon mixture, were similar to the previously reported equilibrated thermodesorption results. TPD profiles were accurately
fitted with a model based on the equilibrium control of the desorption and the adsorption functions derived from the Langmuir
or dual site Langmuir isotherms. 相似文献
14.
Vasilica Lates Delia Gligor Mircea Darabantu Liana M. Muresan 《Journal of Applied Electrochemistry》2007,37(5):631-636
The electrochemical behavior of a new G-2-s-triazine-based dendrimer, 2,4,6-tris-{4-{4,6-bis-{4-{4,6-bis-[(1S,2S)-1,3-dihydroxy-1-(4-nitrophenyl)-prop-2-ylamino]-s-triazin-2-yl}-piperazin-1-yl}-s-triazin-2-yl}-piperazin-1-yl}-s-triazine, (I), was studied in dimethylsulfoxide solution by cyclic voltammetry, on platinum and graphite electrodes. The electrochemical
properties of I were compared with that of one of its precursor, N-{4,6-bis{4-{4,6-bis[(1S,2S)-1,3-dihydroxy-1-(4-nitrophenyl)-prop-2-ylamino]-s-triazin-2-yl}-piperazin-1-yl}-triazin-2-yl}-piperazine), (II), together with that of the starting material, (1S,2S)-2-amino-1-(4-nitrophenyl)-propane-1,3-diol (“p-nitrophenylserinol”), (III). 相似文献
15.
Tsung Min Kuo Terry A. Isbell Alejandro Rooney William E. Levinson Hans Frykman 《Journal of the American Oil Chemists' Society》2007,84(7):639-643
The objective of this study was to explore the extent of microbial conversion of lesquerolic acid (14-hydroxy-cis-11-eicosenoic acid; LQA) by whole cell catalysis and to identify the newly converted products. Among compost isolates including
NRRL strains B-23212 (Sphingobacterium multivorum), B-23213 (Acinetobacter sp.), B-23257 (Enterobacter cloacae B), B-23259 (Escherichia sp.) and B-23260 (Pseudomonas aeruginosa) the S.
multivorum strain was the only microorganism that converted LQA to produce a new product identified as 14-oxo-cis-11-eicosenoic acid by GC-MS and NMR analyses. The conversion yield was 47.4% in 48 h at 200 rpm and 28°C in small shake flask
experiments. In comparison, both Acinetobacter and Pseudomonas strains failed to convert LQA to major new products but used LQA apparently as an energy source during fermentation. For
structural analysis, 6.88 g of 14-oxo-cis-11-eicosenoic acid was produced from converting 11 g LQA (a 62% yield) in 72 h at 200 rpm and 28 °C in Fernbach flasks using
18-h-old NRRL B-23212 cultures and an improved medium that also contained EDTA and glycerol in lieu of glucose as carbon source.
NRRL B-23212 was further identified by 16S rRNA gene sequence analysis as a unique strain of S. multivorum. Therefore, S. multivorum NRRL B-23212 possesses an enzymatic activity presumably a secondary alcohol dehydrogenase for converting LQA to produce 14-oxo-cis-11-eicosenoic acid, a first report that demonstrates the functional modification of LQA by whole cell catalysis. 相似文献
16.
Coccinellid beetles contain a variety of defensive alkaloids that render them unpalatable to predators. Epilachna paenulata (Coleoptera: Coccinellidae) is a South American ladybird beetle that feeds on plants of the Cucurbitaceae family. The defensive
chemistry of E. paenulata has been characterized as a mixture of systemic piperidine, homotropane, and pyrrolidine alkaloids. Whole body extracts of
adult beetles contain four major alkaloids: 2-(2′-oxopropyl)-6-methylpiperidine (1); 1-(6-methyl-2,3,4,5-tetrahydro-pyridin-2-yl)-propan-2-one (2); 1-methyl-9-azabicyclo[3.3.1]nonan-3-one (3); and 1-(2″-hydroxyethyl)-2-(12′-aminotridecyl)-pyrrolidine (4). Comparative studies of the defensive chemistry of eggs, larvae, pupae, and adults showed differences in alkaloid composition
and concentration among life stages. While adults contained mainly the homotropane 1-methyl-9-azabicyclo[3.3.1]nonan-3-one
(3), eggs showed the highest concentration of the piperidine 2-(2′-oxopropyl)-6-methylpiperidine (1). We studied the origin of this alkaloid in the eggs by feeding newly emerged, virgin adult beetles with [2-13C]-labeled acetate, and by performing crosses between 13C-fed and unlabeled males and females. GC-MS analysis of alkaloids from 13C-fed males and females showed high incorporation of 13C into the alkaloids, as evidenced from a 20–30% increase of isotopic peaks in diagnostic fragment ions, confirming the expected
endogenous origin of these alkaloids. In addition, analyses of eggs from different crosses showed that labeled alkaloids from
both parents are incorporated into eggs, indicating that E. paenulata males transfer alkaloids to the females at mating. Biparental endowment of chemical defenses into eggs has been shown previously
in insects that acquire defensive compounds from dietary sources. To our knowledge, this is the first report of biparental
egg endowment of endogenous defenses.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
17.
Gökhan Demirel 《Journal of Polymer Research》2007,14(1):23-30
In the present study, a series of ionic poly(N-t-butylacrylamide-co-acrylamide) [P(NTBA-co-AAm)] hydrogels were synthesized by free-radical crosslinking copolymerization
of N-t-butylacrylamide (NTBA) and acrylamide (AAm) monomers in fixed amount, but changing amount of maleic acid (MA) comonomer in
methanol using N,N-methylene-bis-acrylamide (BAAm) as the crosslinker, ammonium persulfate (APS) as the initiator, and N,N,N′,N′-tetramethylethylenediamine (TEMED) as the activator. The swelling behavior of these hydrogels was analyzed in buffer solutions
at various pHs. The prepared hydrogels also were investigated swelling-deswelling transition in water depending on the temperature.
For the bovine serum albumin (BSA) adsorption, the effect of pH, temperature, initial protein concentration and adsorption
rate were investigated. Maximum BSA adsorption was observed at pH 5.0 which is close to the isoelectric pH of BSA (pH 4.8).
The highest adsorption rate was achieved in about 12 h. and also, maximum BSA adsorption was found at +5°C. 相似文献
18.
Chakra Wijesundera Claudio Ceccato Peter Fagan Zhiping Shen Wayne Burton Phil Salisbury 《Journal of the American Oil Chemists' Society》2008,85(8):693-699
Canola-quality Indian mustard (Brassica juncea) is being developed as a complimentary oilseed crop to canola (Brassica napus) for cultivation in hot and low-rainfall areas, where canola does not perform well. In Australia, several B. juncea breeding lines have been developed for commercial cultivation and for eventual processing as canola oil. However, there still
are significant species-based differences in the fatty acid composition with B. juncea containing lower levels of linoleic acid and higher levels of oleic and linolenic acids compared with B. napus. This has raised concern about possible oxidative stability differences between the oils. Oils (unrefined) extracted from
different breeding lines of each species were subjected to accelerated autoxidation, and development of oxidative rancidity
was assessed by four separate techniques: depletion of polyunsaturated fatty acids, depletion of tocopherol, development of
primary oxidation products, and development of secondary oxidation products (propanal and hexanal). All the tests showed that
the newly developed B. juncea oils are more stable to autoxidation than conventional canola (B. napus) oil, despite containing marginally higher linolenic levels. Oxidative stability does not appear to be a barrier to using
oils from these emerging lines of B. juncea for partial or full replacement of conventional canola oil. 相似文献
19.
Jeyasankar Alagarmalai David Nestel Daniela Dragushich Ester Nemny-Lavy Leonid Anshelevich Anat Zada Victoria Soroker 《Journal of chemical ecology》2009,35(5):542-551
The Ethiopian fruit fly, Dacus ciliatus, is an oligophagous pest of cucurbit crops, particularly melons, cucumbers, and marrows (summer squash). The present study
aimed to identify host attractants for D. ciliatus and was guided by a behavioral bioassay and an electrophysiological assay. We tested volatile compounds from the fruits of
a host plant, ripe and unripe Galia melon, Cucumis melo var. reticulates. Both sexes were attracted to melon volatiles. Those of ripe melon were preferred. Gas chromatography-electroantennographic
detection analysis of the behaviorally active ripe melon volatiles consistently showed that 14 compounds elicited similar
antennal responses from both sexes. Twelve compounds were identified by gas chromatography-mass spectrometry (GC-MS) using
GC-MS libraries, retention indices (RI), and authentic standards. The electrophysiological activities of the compounds that
were present at sufficient levels for identification, benzyl acetate, hexanyl acetate, (Z)-3-hexenyl acetate, (Z)-3-octenyl acetate, octanyl acetate, (Z)-3-decenyl acetate, and (E)-β-farnesene, were evaluated at six different dosage levels by using electroantennography (EAG). Benzyl and hexanyl acetates
elicited dose responses only in males, while other tested compounds elicited dose responses in both sexes. The strongest responses
were observed for doses between 100 ng and 10 μg. The dose response, in terms of attractiveness to synthetic compounds within
the active range (as determined by EAG), also was evaluated in the behavioral bioassay. Synthetic acetates were attractive
to both sexes when tested individually. Significant attraction was observed when individual compounds were applied in the
bioassay arena at doses of 0.5–1 μg/dispenser. Blends of compounds in equal proportions also were attractive to the insects.
The most attractive blend was a mixture of four or five identified acetates. The addition of an equal proportion of (E)-β-farnesene to this mixture had a deterrent effect. 相似文献
20.
Flavio H. Oliveira Marly E. Osugi Fabiana M. M. Paschoal Demetrius Profeti Paulo Olivi Maria Valnice Boldrin Zanoni 《Journal of Applied Electrochemistry》2007,37(5):583-592
The generation of active chlorine on Ti/Sn(1−x)Ir
x
O2 anodes, with different compositions of Ir (x = 0.01, 0.05, 0.10 and 0.30 ), was investigated by controlled current density electrolysis. Using a low concentration of
chloride ions (0.05 mol L−1) and a low current density (5 mA cm−2) it was possible to produce up to 60 mg L−1 of active chlorine on a Ti/Sn0.99Ir0.01O2 anode. The feasibility of the discoloration of a textile acid azo dye, acid red 29 dye (C.I. 16570), was also investigated
with in situ electrogenerated active chlorine on Ti/Sn(1−x)Ir
x
O2 anodes. The best conditions for 100% discoloration and maximum degradation (70% TOC reduction) were found to be: NaCl pH 4,
25 mA cm−2 and 6 h of electrolysis. It is suggested that active chlorine generation and/or powerful oxidants such as chlorine radicals
and hydroxyl radicals are responsible for promoting faster dye degradation. Rate constants calculated from color decay versus
time reveal a zero order reaction at dye concentrations up to 1.0 × 10−4 mol L−1. Effects of other electrolytes, dye concentration and applied density currents also have been investigated and are discussed. 相似文献