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1.
A novel and versatile synthetic approach to the preparation of (E)‐non‐6‐en‐1‐ol, a sex pheromone of the Mediterranean fruit fly, Ceratitis capitata, is presented. This pheromone can be viewed as potential active component for lures designed to control and eradication of Mediterranean fruit fly. The described protocol is a six‐step reaction sequence producing the desired compound with 28% overall yield from commercially available and inexpensive starting material and total E stereoselectivity of the double bond present in final structure. The key to the success of the presented strategy is application of lithiated α‐allylphosphoramido carbanions and their reaction with halogenated acetals. © 2010 Wiley Periodicals, Inc. 21:139–147, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20588  相似文献   

2.
Ag (I) nanoclusters doped in mordenite zeolite were prepared and spectroscopically analyzed. Strong luminescence emission that is dependent on the excitation wavelength was observed. These variations in the emission modes are due to the site selective luminescence where various luminophores might be excited upon selecting the proper excitation wavelength. The selected material was found to have strong affinity to remove the quinalphos pesticide, which is widely used for the protection of several vegetable and fruit crops, from water bodies. HPLC and GC–MS techniques were used to follow the kinetic data and to identify the photodecomposition products, respectively. The photodecomposition of quinalphos in the presence of the silver doped mordenite catalyst gives different products compared to the irradiation of quinalphos without catalyst. The presence of the Ag-mordenite catalyst not only adsorbs the quinalphos from the solution but it also reduces its toxic effect as tested on the fruit fly (Drosophila melanogaster).  相似文献   

3.
The calorimetric data of binders containing pure Portland cement, 20% fly ash, 20% slag and 10% silica fume respectively are determined at different initial casting temperatures using an adiabatic calorimeter to measure the adiabatic temperature rising of concrete. The calorimetric data of binders with different dosages of fly ash at two water binder ratios (w/b) are determined, too. Elevation of initial casting temperature decreases the heat evolution of binder, enhances the heat evolution rate of binder and increases the heat evolution rate of binder at early age. The dosage of fly ash in concrete has different effects on the heat evolution of binder with different w/b. At high w/b ratio the heat evolution of binder decreases when dosage of fly ash increases. At low w/b ratio the heat evolution of binders increases when dosage of fly ash increases from 0 to 40% of total binder quantity. The heat evolution of binder decreases after the dosage of fly ash over 40%. An appropriate dosage of fly ash in binder benefits the performance of concrete at low w/b ratio.  相似文献   

4.
Melon fly (Bactrocera cucurbitae) is the most common pest of cucurbits, and it directly causes damage to cucurbit fruits in the early developmental stage. The infection of fruit tissues induces oxidative damage through increased generation of cellular reactive oxygen species. The effects of melon fly infestation on the production of defensive enzymes and antioxidant capabilities in five cucurbit species, namely, bottle gourd, chayote, cucumber, snake gourd, and bitter gourd, were investigated in this study. The total phenolic and flavonoid content was considerably higher in melon fly infestation tissues compared to healthy and apparently healthy tissues. The chayote and bottle gourd tissues expressed almost 1.5- to 2-fold higher phenolic and flavonoid contents compared to the tissues of bitter gourd, snake gourd, and cucumber upon infestation. Defensive enzymes, such as peroxidase (POD), superoxide dismutase (SOD), polyphenol oxidase (PPO), and catalase (CAT), were high in healthy and infected tissues of chayote and bottle gourd compared to bitter gourd, snake gourd, and cucumber. The activity of POD (60–80%), SOD (30–35%), PPO (70–75%), and CAT (40–50%) were high in infected chayote and bottle gourd tissue, representing resistance against infestation, while bitter gourd, snake gourd, and cucumber exhibited comparatively lower activity suggesting susceptibility to melon fly infection. The antioxidant properties were also high in the resistant cucurbits compared to the susceptible cucurbits. The current research has enlightened the importance of redox-regulatory pathways involving ROS neutralization through infection-induced antioxidative enzymes in host cucurbit resistance. The melon fly infestation depicts the possible induction of pathways that upregulate the production of defensive enzymes and antioxidants as a defensive strategy against melon fly infestation in resistant cucurbits.  相似文献   

5.
Coal bioprocessing research at the institute of gas technology   总被引:1,自引:0,他引:1  
Coal bioprocessing research at the Institute of Gas Technology (IGT) has included solubilization, gasification, desulfurization, denitrogenation, production of specialty chemicals, and the remediation of organic and inorganic wastes associated with coal utilization. Currently, research is focused on desulfurization and remediation. Desulfurization research concerns the development of processes to remove organic sulfur or to convert a portion of pyritic sulfur to sulfuric acid rapidly, thereby serving as a pretreatment to aid the thermochemical conversion of coal to coke and liquid products. The removal of as much as 91% organic sulfur from coal has been achieved, and biodesulfurization of coal has been confirmed by seven analytical techniques performed in six different laboratories. Recent studies have involved the use of molecular genetics to develop strains of bacteria with higher levels of desulfurization activity, and the development of methods for the preparation, storage, and utilization of biodesulfurization catalysts. Remediation studies include the development ofin situ and on-site technologies to treat soil contaminated with coal tar, the leaching of metals from fly ash, and the treatment of waste water resulting from fly ash leaching or from acidic mine drainage (AMD). IGT currently has two projects in EPA’s SITE program concerned with the remediation of coal tar-contaminated soil, and other related technologies are being developed. Efficient laboratory-scale processes for the removal of metals from fly ash and from soil so that the solids pass EPA’s TCLP test, and the subsequent treatment of the leachates or AMD to meet all regulatory requirements have been developed. Data obtained in these projects are presented in particular, and a general discussion of the application of biotechnology to coal is offered.  相似文献   

6.
This paper presents the development of wavelet neural network (WNN) with an improved fruit fly optimization algorithm (IFOA) for the melt index prediction in the industrial propylene polymerization process. The structure, calculation, and prediction process of WNN are proposed, and the improved details of IFOA are introduced, which can enhance the searching efficiency and improve the searching quality over the traditional fruit fly optimization algorithm. Finally, the WNN–IFOA model can obtain the least predicting errors compared with other existing models and shows better generality for the online melt index prediction from the experimental results. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

7.
The olive fruit fly pheromone avidin-biotin ELISA immunoassay, based on the use of polyclonal G antibodies derived from rabbits (reported previously) and a newer assay, based on the use of polyclonal Y antibodies isolated from the eggs of laying hens (reported in this paper), were applied successfully for the analysis of natural pheromone in virgin adult female olive fruit flies. According to the results obtained, the pheromone content in the glands of adult female olive fruit flies increases from the third to the ninth day of their age. During the calling period, the female olive fruit flies seem to emit approximately 1.1microg pheromone/insect/day at least. The immunoassay, based on the Y antibodies, is slightly more sensitive (detection limit 40ng/mL) than the assay based on polyclonal anti-pheromone rabbit antiserum (detection limit 80ng/mL). As revealed by thorough cross-reactivity studies, including 14 structurally similar to the olive fruit fly pheromone molecules, the newer immunoassay is less selective than the previous one and seems to cross react with few molecules bearing the spiroketal moiety.  相似文献   

8.
Bactrocera oleae, the olive fruit fly, is one of the most important pests affecting the olive fruit, causing serious quantitative and qualitative damage to olive oil production. In this study, the changes induced by B. oleae infestation in the biosynthesis of volatile and phenolic compounds in olive (cvs. Picual, Manzanilla, and Hojiblanca) have been analyzed. Despite cultivar differences, the oils obtained from infested fruits showed a significant increase in the content of certain volatile compounds such as (E)-hex-2-enal, ethanol, ethyl acetate, and β-ocimene and a drastic decrease of the phenolic contents. The impact of those changes on the inferred quality of the oils has been studied. In parallel, the changes induced by the attack of the olive fly on the expression of some key genes in the biosynthesis of volatile and phenolic compounds, such as lipoxygenase, β-glucosidase, and polyphenol oxidase, have been analyzed. The strong induction of a new olive polyphenol oxidase gene (OePPO2) explains the reduction of phenolic content in the oils obtained from infested fruits and suggest the existence of a PPO-mediated oxidative defense system in olives.  相似文献   

9.
[reaction: see text] A biosynthetic scheme rationalizing the formation of (+/-)-1,7-dioxaspiro[5.5]undecane (5) in the fruit fly species Bactrocera cacuminata and Bactrocera oleae (olive fruit fly) is presented. Incorporation studies with deuterium-labeled keto aldehyde (10), 1,5-nonanediol (11), and 1,5,9-nonanetriol (12), and our previous finding that both oxygen atoms of 5 originate from dioxygen, are strongly evidentiary. The racemic condition of the natural spiroacetal 5 is accounted for, and inter alia, it is demonstrated that dihydropyran (18) is not an important intermediate en route to 5.  相似文献   

10.
Acanthopanax senticosus (Rupr. et Maxim.) Harms, a traditional Chinese medicine, has been widely used to improve the function of skeleton, heart, spleen and kidney. This fruit is rich in nutrients, but the chemical constituents of Acanthopanax senticosus fruit are still unclear. A rapid method based on ultra high performance liquid chromatography with time‐of‐flight mass spectrometry was developed for the compound analysis of Acanthopanax senticosus fruit in vitro and in vivo. In this study, the Acanthopanax senticosus fruit could significantly increase the weight of immune organs, promote the proliferation of lymphatic T cells, regulate the lymphatic B cell function, and decrease the ability of natural killer cells. A total of 104 compounds of Acanthopanax senticosus fruit including lignans, flavones, triterpenoidsaponins, phenolic acids, and other constituents were identified. Among them, seven chemical compounds were reported for the first time in the Acanthopanax senticosus fruit. Compared with the serum sample of blank and dosed samples, 24 prototype compositions were characterized. The results of our experiment could be helpful to understand the complex compounds of Acanthopanax senticosus fruit in vitro and in vivo for further pharmacological activity studies.  相似文献   

11.
We have recently proposed the use of porphyrin sensitizers as photoinsecticidal agents. Our present findings show that the phototoxic efficiency of porphyrins toward the Mediterranean fruit fly Ceratitis capitata is strongly dependent on their chemical structure. Thus, two highly hydrophilic porphyrins, such as a tetraanionic and a te-tracationic meso-substituted derivative, show a very low photoactivity even upon prolonged irradiation with full-spectrum visible light. The phototoxicity increases upon increasing the hydrophobicity of the porphyrin molecule; out of the compounds examined by us, the highest pho-tocidal activity is exhibited by a dicationic amphophilic porphyrin, namely cis-(JV-methyl-piridyl), c/s-diphenyl-porphine, which causes 100% mortality upon 1 h irradiation with a fluence rate of 1220 μ.E s-lm-2even at a concentration as low as 0.85 mM. The differences in photoactivity are not related to differences in the photo-physical and photobiological properties or to differences in the rate of porphyrin uptake and clearance by the flies.  相似文献   

12.
Solanum americanum Mill. is a plant that belongs to the Solanaceae family, its respective ripe fruit is dark purple. Ripe S. americanum Mill. fruits were submitted to physicochemical characterisation, and their trans-resveratrol contents were quantified by high-performance liquid chromatography. Such determination was executed with fruits at different stages of ripeness and freeze-stored fruits as well. In natura ripe fruit pulp and peel presented average trans-resveratrol amounts of 1.07 and 0.7960 μg per gram of sample, respectively. These amounts are significantly higher when compared to freeze-stored fruit (0.1353 μg of trans-resveratrol per gram of sample) and to other berries. All ripe fruits showed significant amounts of total anthocyanins and total antioxidants. Thus, for the first time, trans-resveratrol has been identified and quantified in S. americanum Mill. fruit samples.  相似文献   

13.
Summary A semi-preparative high-performance liquid chromatographic procedure on 5-m silica was developed for the isolation of gram quantities of ethyltrans-5-iodo-trans-2-methylcyclohexane-1-carboxylate (B1) and ethyltrans-4-iodo-trans-2-methylcyclohexane-1-carboxylate (B2) for comparative evaluation as male Mediterranean fruit fly,Ceratitis capitata, attractants and for NMR studies. This procedure can also be used analytically to determine the content of B1 (the attractive isomer) in ceralure, the ethyl 4- and 5-iodo-trans-2-methylcyclohexane-1-carboxylate mixture. 1,1-Dimethylethylcis-5-iodo-trans-2-methylcyclohexane-1-carboxylate (A) and 1,1-dimethylethylcis-4-iodo-trans-2-methylcyclohexane-1-carboxylate (C) were isolated and converted to their ethyl esters, thus supplying the fourtrans-isomers of ceralure.  相似文献   

14.
The present study analyzed the chemical composition of Juniperus foetidissima Willd. essential oils (EOs) and evaluated their attractancy and toxicity to two agriculturally important tephritid fruit flies. The composition of hydrodistilled EOs obtained from leaves (JFLEO) and fruits (JFFEO) of J. foetidissima was analyzed by GC–FID and GC–MS. The main compounds were α-pinene (45%) and cedrol (18%) in the JFLEO and α-pinene (42%), α-thujone (12%), and β-thujone (25%) in the JFFEO. In behavioral bioassays of the male Mediterranean fruit fly, Ceratitis capitata (Wiedemann), both JFLEO and JFFEO showed strong attraction comparable to that observed with two positive controls, Melaleuca alternifolia and Tetradenia riparia EOs. In topical bioassays of the female Caribbean fruit fly, Anastrepha suspensa (Loew), the toxicity of JFFEO was two-fold higher than that of JFLEO, with the LD50 values being 10.46 and 22.07 µg/µL, respectively. This could be due to differences in chemical components between JFLEO and JFFEO. The JFFEO was dominated by 48% monoterpene hydrocarbons (MH) and 46% oxygenated monoterpenes (OM), while JFLEO consisted of 57% MH, 18% OM, and 20% oxygenated sesquiterpenes (OS). This is the first study to evaluate the attractancy and toxicity of J. foetidissima EOs to tephritid fruit flies. Our results indicate that JFFEO has the potential for application to the management of pest tephritid species, and further investigation is warranted.  相似文献   

15.
The k 0-method of standardisation for instrumental neutron activation analysis (INAA) has been used at the OPAL research reactor to determine the elemental composition of three certified reference materials: coal fly ash (SRM 1633b), brick clay (SRM 679) and Montana soil (SRM 2711). Of the 41 certified elements in the three materials, 88 percent were within five percent of the certified values and all determinations were within 15 percent of the certified values. The average difference between the measured and certified values was 0.1 percent, with a standard deviation of 4.1 percent. Since these reference materials are widely used as standards in the analysis of archaeological ceramics by INAA, it has been concluded that the INAA facility in Australia is particularly well-suited for nuclear archaeometry.  相似文献   

16.
This study was designed to determine the adaptation capability of bitter melon (Momordica charantia L.), which is widely grown in tropical and subtropical climates, in northern parts of Turkey. In this study, plant height, number of fruits, fruit length, fruit width, number of seeds and fruit weight of bitter melon grown in field conditions were determined. The antimicrobial effect of the ethanol extract of fruit and seeds against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Salmonella typhi, Aspergillus niger and Candida albicans microorganisms was tested in vitro by the disc diffusion method. In conclusion, plant height (260 cm), number of fruits (16 per plant), number of seeds (30.2 per fruit), fruit width (3.8 cm), fruit length (10.6 cm) and fruit weight (117.28 g fruit? 1) were determined; fruits were found to have antimicrobial activity against A. niger; oil and seeds were found to have antimicrobial activity against A. niger and E. coli.  相似文献   

17.
A concentrate of the volatile flavor of yellow passion fruit (Passiflora edulis f. flavicarpa) has been prepared. Investigation by gas liquid chromatography and mass spectrometry led to the identification of 165 compounds, 161 of which were not previously found in passion fruit. Some of these substances are new naturally occurring flavor compounds.  相似文献   

18.
The Ti-catalyzed intermolecular cross-cyclomagnesiation reaction of aliphatic and oxygenated 1,2-dienes with Grignard reagents was used as the key step to develop facile stereoselective methods for preparation of the major components of citrus leafminer moth (Phyllocnistis citrella) pheromones as well as cotton pink bollworm (Pectinophora gossypiella) and fruit fly (Drosophila melanogaster) attractants.  相似文献   

19.

The viability of ground coal bottom ash as a potential Portland cement constituent to be used in building materials is assessed. Currently, coal fly ash is used to produce Portland cements and concretes. However, coal bottom ash is mainly landfilled. Gamma spectrometry analysis, compressive strength, physical and chemical testing were performed. The ground coal bottom ash activity concentration index (I = 1.03) was compared to that of the coal fly ash (I = 1.11) provided from the same thermo-electrical power plant. Ground coal bottom ash could be used in building materials in the same way as coal fly ash as a Portland cement constituent.

  相似文献   

20.
Abstract— The chromophore of the visual pigment of the fruit fly Drosophila melanogaster was studied by high-pressure liquid chromatography (HPLC). Oxime derivatives of the chromophore were successfully analyzed with a more polar solvent than has been used for retinaloximes. A preceding monochromatic irradiation resulted in reversible interchanges in the amount among geometric isomers of the oximes that reflected the photointerconversion of rhodopsin and metarhodopsin of the peripheral photoreceptors (Rl-R6). Authentic all- trans -3-h-ydroxyretinal was used to identify the chromophore from metarhodopsin. Results demonstrated that the chromophore of the visual pigment in Drosophila is 3-h-ydroxyretinal as was proposed in larger flies.  相似文献   

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