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1.
Elimination and metabolic profiles of the O-glucuronide conjugated products of pyrilamine and their nonconjugated O-dealkylated and N-desmethyl pyrilamine products were determined after the oral administration of (14C)-pyrilamine maleate to Fischer 344 rats, B6C3F1 mice and female rhesus monkeys by stomach tube or i.v. The total cumulative urinary and fecal pyrilamine products were determined. The conjugated pyrilamine metabolites, isolated and identified were the glucuronide products of O-dealkylated pyrilamine and ring-hydroxylated pyrilamine, and the nonconjugated metabolites were predominately the N-desmethylpyrilamine and O-dealkylated pyrilamine and their ring-hydroxylated products. Statistically significant differences were observed in the percentages of the conjugated and nonconjugated metabolites of pyrilamine excreted by the three species studied.  相似文献   

2.
O-Nitratedchitosan (d.s. 1.5–1.8 for NO2 was N-acylated with carboxylic anhydride to afford products (d.s. 1.4–1.8 for NO2 in 78–100% yield, and N-acylchitosan (d.s. 1.0 for N-acyl was nitrated with fuming nitric acid-acetic anhydride to afford products (d.s. 1.7–2.0 for NO2 in 90–100% yield. N-Benzoylchitosan was nitrated with fuming nitric acid-acetic anhydride to afford a product of d.s. 3.0 for NO2. All the products were soluble in methanesulphonic acid. The nitrated products containing N-fatty acyl groups (> C2) were soluble in N, N-dimethylformamide and dimethyl sulphoxide, but the nitrated products containing N-fatty acyl groups (> C6) were insoluble or swelled. O-Nitrated chitosan (d.s. 1.5–1.8 for NO2) had ignition points 150–1562C, but the nitrated products containing N-acyl groups had no ignition point, and decomposed at over 2402C.  相似文献   

3.
Venturia canescens (Gravenhorst) is an ichneumonid generalist parasitoid that successfully attacks the larvae of different lepidopteran pests that infest stored products. These pest species include Plodia interpunctella and Ephestia kuehniella. In this study, we aimed to evaluate the influence of the rearing host on the parasitoid’s ability to detect and respond to a new host different from the rearing species. For this reason, the trials tested the preference of parasitoids reared on P. interpunctella or E. kuehniella for products that were or were not infested with larvae of these hosts. The trials were conducted in a Y-tube olfactometer. Regardless of the rearing host species, the parasitoids showed no preference for uninfested products. The parasitoids were attracted to products infested with larvae of their rearing host in preference to uninfested products. They also showed preferential attraction to products infested with the new host over uninfested products. E. kuehniella was the preferred host, irrespectively of the parasitoid host rearing species. The results are discussed to develop a better understanding of the ecology of V. canescens for its application in biological control.  相似文献   

4.
Alicyclobacillus are spoilage microbes of many juice products, but contamination of kiwi products by Alicyclobacillus is seldom reported. This study aims to investigate the whole production line of kiwi products in China to assess the potential risk of their contamination. A total of 401 samples from 18 commercial products, 1 processing plant and 16 raw material orchards were tested, and 76 samples were positive, from which 76 strains of microbes were isolated and identified as 4 species of Alicyclobacillus, including Alicyclobacillus acidoterrestris, Alicyclobacillus contaminans, Alicyclobacillus herbarius and Alicyclobacillus cycloheptanicus, and another 9 strains as 3 species of Bacillus by sequencing of their 16S rDNA. Through phylogenetic tree construction and RAPD-PCR amplification, it was found that there exist genotypic diversities to some extent among these isolates. Four test strains (each from one species of the 4 Alicyclobacillus species isolated in this study) could spoil pH adjusted kiwi fruit juice and some commercial kiwi fruit products with producing guaiacol (11–34 ppb).  相似文献   

5.
In vitro translation products of polyadenylated RNA from untreated and auxin-treated basal sections of soybean (Glycine max var. Wayne) hypocotyl were analyzed by two-dimensional polyacrylamide gel electrophoresis. Within one hour of 2,4-dichlorophenoxyacetic acid treatment, the translatable messenger RNAs for at least twelve in vitro translation products are modulated upward. In vitro translation products of polyadenylated RNA from untreated, auxin-treated and Ethephon-treated intact soybean hypocotyl were also analyzed. Within two hours of treatment with either 2,4-dichlorophenoxyacetic acid or Ethephon, the translatable messenger RNAs for a group of high molecular weight in vitro translation products are modulated upward. There is a particular set of translatable messenger RNA, encoding in vitro translation products in the 24,000 to 32,000 molecular weight range, that is specifically modulated upward by auxin treatment in intact soybean hypocotyl and in hypocotyl sections.  相似文献   

6.
A novel method of rapid and specific detection of polymerase chain reaction (PCR) products from bacterial genomes using Zn finger proteins was developed. Zn finger proteins are DNA-binding proteins that can sequence specifically recognize PCR products. Since Zn finger proteins can directly detect PCR products without undergoing dehybridization, unlike probe DNA, and can double check the specific PCR amplification and sequence specificity of the PCR products, this novel method would be quick and highly accurate. In this study, we tried to detect Legionella pneumophila using Sp1. It was found that a 49 bp L. pneumophila-specific region containing the Sp1 recognition site is located on the flhA gene of the L. pneumophila genome. We succeeded in specifically detecting PCR products amplified from L. pneumophila in the presence of other bacterial genomes by ELISA, and demonstrated that Sp1 enables the discrimination of L. pneumophila-specific PCR products from others. By fluorescence depolarization measurement, these specific PCR products could be detected within 1 min. These results indicate that the rapid and simple detection of PCR products specific to L. pneumophila using a Zn finger protein was achieved. This methodology can be applied to the detection of other bacteria using various Zn finger proteins that have already been reported.  相似文献   

7.
In vitro translation products of polyadenylated RNA from untreated and auxin-treated elongating sections of soybean (Glycine max var. Wayne) hypocotyl were analyzed by two-dimensional polyacrylamide gel electrophoresis. The levels of translatable messenger RNA for at least ten in vitro translation products are increased by auxin treatment. The induction by auxin occurs rapidly (within 15 minutes), and the amounts of the induced in vitro translation products increase with time of auxin treatment. Indoleacetic acid has the same effect on the population of translatable messenger RNA as 2,4-dichlorophenoxyacetic acid. The auxin-induced in vitro translation products disappear rapidly when Actinomycin D is present during the last two hours of a three-hour auxin treatment.  相似文献   

8.
The glnL product is not necessary for the control of expression of glnA and other nitrogen-regulated genes, but it presumably communicates reduntant information on the availability of ammonia from an ammonia-sensitive system consisting of the products of glnB and glnD to the regulatory products of glnF and glnG.  相似文献   

9.
The products of hydrolytic action of 18 enzyme preparations at pH 3·5 and 5·5 on pectate were analyzed by gel-filtration chromatography early in the course of reaction (8–15% hydrolysis), and at a time 10 times that required for 10% hydrolysis. The degree of hydrolysis at the latter time varied from 25 to 74%. Three patterns of oligosaccharide production could be distinguished: endo-hydrolysis, exo-hydrolysis, and that due to S-polygalacturonase. The initial products of endo-hydrolysis were mixed oligosaccharides 5–30 units long; monomer and dimer appeared early but represented less than 2% of the products until late in the reaction. exo-Polygalacturonase (not entirely free of endo-) showed predominant production of the monomer and was clearly evident when mixed with four parts of endo-polygalacturonase. The time course of reducing group production by highly purified S-polygalacturonase could be reproduced by the above mixture of exo- and endo-polygalacturonases, but the pattern of products and the pH relations could not. The initial products of S-polygalacturonase were monomer, dimer and pentamer with lesser amounts of trimer and tetramer. After the hydolysis of the polymer and large oligomers, the pentamer was attacked by S-polygalacturonase, in the same way that the accumulated hexamer, etc. were finally hydrolysed by the endo-polygalacturonase.  相似文献   

10.
In vitro synthesis of bacteriophage f1 proteins   总被引:42,自引:0,他引:42  
  相似文献   

11.
A membrane-bound enzyme, which catalyses the cleavage of fatty acid hydroperoxides to carbonyl fragments, has been partially purified from cucumber fruit. The isomeric 9- and 13-hydroperoxydienes (but not the hydroxydienes) derived from both linoleic and linolenic acids are cleaved by the enzyme but a mixture of 9- and 10-hydroperoxymonoenoic derivatives of oleic acid was not attacked. No evidence was obtained for free intermediates between fatty acid hydroperoxides and the cleavage products. Major volatile products were: cis-3-nonenal and hexanal (from 9- and 13-hydroperoxides of linoleic acid respectively) or cis-3,cis-6-nonadienal and cis-3-hexenal (from 9- and 13-hydroperoxides of linolenic acid). The increase in the ratio of cis-3- to trans-2-enal products with enzyme purification indicated that cis-3-enals are the immediate cleavage products and that the trans-2- forms are produced by subsequent isomerization.  相似文献   

12.
Intra-species fusion products of Saccharomyces cerevisiae, Saccharomyces unisporus and Torulopsis glabrata have been isolated following polyethylene glycol-induced fusion of protoplasts and selection for prototrophic colonies. Staining with lomofungin showed that all fusion products were uninucleate. Measurement of DNA content mostly gave values between haploid and diploid levels indicating that the majority of fusion products were aneuploid. Nevertheless fusion products of S. cerevisiae and S. unisporus were, as expected, more resistant to X-irradiation than their haploid parents. By contrast, the X-ray doze—response curve of all T. glabrata fusion products was indistinguishable from their progenitors despite the fact that mitotic segregants could be recovered amongst the survivors to X-rays. A possible explanation for the behaviour towards X-rays of T. glabrata fusion products is that this species lacks a DNA repair pathway involving recombination between homologous chromosomes. We conclude from this study that the shape of the X-ray dose—response curve should not be taken to indicate the ploidy of new yeast isolates without supporting data.  相似文献   

13.
The following products have been isolated from methyl-labelled N-methyl-N-nitrosourea (MNUA) and DNA after reaction at pH 8: 1-, 3-, 7-methyladenines, 3-methyldeoxycytidine, 3-, 7- and O6-methylguanines, 3- and O4-methylthymidines. Comparison of C3H3 and 14CH3 labelling showed that the ratio 3H14C in the products was the same and equal to that in the original reagents, in accord with the concept that the methyl group is transferred intact, and not via diazomethane. In some cases, most notably with O6-methyldeoxyguanosine, the 3H-labelled products were found to elute from Dowex 50 (NH4+ form) slightly ahead of 14C-labelled or unlabelled products.  相似文献   

14.
2,6-Anhydro-1-deoxy-1-diazo-D-glycero-L-manno-heptitol (2) decomposes in 0.01M methanolic sodium methoxide with a half-life of approx. 18 min. Decomposition in aqueous solution is too rapid for spectrophotometric measurement. Seven products could be identified in methanolic and aqueous reaction mixtures. 2,6-Anhydro-1-deoxy-D-galacto-hept-1-enitol (6), 2,7-anhydro-1-deoxy-β-D-galacto-heptulopyranose (10), and 4-O-vinyl-D-lyxose (12) are products of rapid intramolecular reactions. The major portion consists of the direct solvolysis products 2,6-anhydro-1-O-methyl-D-glycero-L-manno-heptitol (3) and 2,6-anhydro-D-glycero-L-manno-heptitol (5).  相似文献   

15.
The utilization of native trichogrammatids for biocontrol of Helicoverpa armigera (Hbn.) and their potential integration with pesticide use are currently receiving attention. In this study the interaction of adults of Trichogramma sp. nr. mwanzai and Trichogrammatoidea sp. nr. lutea with commonly used pesticide products was investigated. The toxicity of eight pest control products commonly used in vegetable crops in Kenya, were evaluated by exposing the adults of the two species to detached potted tomato leaves at different intervals after spraying. Two biologically derived products, Achook? (neem-based) and Dipel? (Bt ssp. kurstaki)—were found to be harmless and had no persistent toxicity on both the trichogrammatid species. Two organophosphate products tested, dimethoate (Rogor?) and malathion (Malathion?) were found to be ‘slightly harmful’ and ‘moderately persistent’ respectively. Three other synthetic insecticides, lambdacyhalothrin (Karate?), bifenthrin (Brigade?) and alpha-cypermentrin (Fastac?) were found to be ‘moderately harmful’ and ‘persistent’ respectively. Polytrin? (mixture of cypermethrin and profenofos) was also found to be persistent but only ‘slightly harmful’. On the basis of five concentrations tested (0.032, 0.016, 0.008, 0.004 and 0.002 of the recommended field rates) the LC50 values for adult T. sp. nr. mwanzai were estimated as 285, 411, 435 and 1,916 (μg active ingredient (a.i) ml?1) for dimethoate; malathion; lambdacyhalothrin as well as cypermethrin?+?profenofos respectively. The corresponding values for T. sp. nr. lutea were 247, 251, 278 and 697 respectively. Further, Karate? appeared to be the least toxic among the four products, across all the respective concentrations. The study was an attempt to adopt the methodologies of the IOBC (International Organization for Biological Control) on non-target risk assessment for pest control products to cater for the local needs of integrating the use of the trichogrammatids along with other pest control products.  相似文献   

16.
Glucosinolates are a diverse class of S- and N-containing secondary metabolites that play a variety of roles in plant defense. In this study, we used Arabidopsis thaliana mutants that contain different amounts of glucosinolates and glucosinolate-breakdown products to study the effects of these phytochemicals on phytopathogenic fungi. We compared the fungus Botrytis cinerea, which infects a variety of hosts, with the Brassicaceae-specific fungus Alternaria brassicicola. B. cinerea isolates showed variable composition-dependent sensitivity to glucosinolates and their hydrolysis products, while A. brassicicola was more strongly affected by aliphatic glucosinolates and isothiocyanates as decomposition products. We also found that B. cinerea stimulates the accumulation of glucosinolates to a greater extent than A. brassicicola. In our work with A. brassicicola, we found that the type of glucosinolate-breakdown product is more important than the type of glucosinolate from which that product was derived, as demonstrated by the sensitivity of the Ler background and the sensitivity gained in Col-0 plants expressing epithiospecifier protein both of which accumulate simple nitrile and epithionitriles, but not isothiocyanates. Furthermore, in vivo, hydrolysis products of indole glucosinolates were found to be involved in defense against B. cinerea, but not in the host response to A. brassicicola. We suggest that the Brassicaceae-specialist A. brassicicola has adapted to the presence of indolic glucosinolates and can cope with their hydrolysis products. In contrast, some isolates of the generalist B. cinerea are more sensitive to these phytochemicals.  相似文献   

17.
The occurrence of the hemolysin genes, tdh and trh, in Vibrio parahaemolyticus strains isolated from environmental samples collected from various exported seafood products comprising of fishes and shellfish (Mytilus edulis and Crassostrea gigas) or seawater, was studied. Eight strains were confirmed as V. parahaemolyticus by toxR -based polymerase chain reaction and only one strain out of these 8 strains was positive for tdh and trh genes. Toxigenic V. parahaemolyticus isolates are present in Tunisian coastal areas and they may also be present in Tunisian exported seafood products.  相似文献   

18.
cis-Urocanic acid (cis-UCA), formed from trans-urocanic acid (trans-UCA) by photoisomerization, has been shown to mimic suppressive effects of UV on the immune system. It is our hypothesis that UCA oxidation products in the skin play a role in the process of immunosuppression. Recently, both UCA isomers were found to be good hydroxyl radical scavengers and in this context we investigated the formation of products resulting from the interaction of hydroxyl radicals with UCA. Hydroxyl radicals were generated by (1) UV/H2O2 (photooxidation), (2) ferrous ions/H2O2 (Fenton oxidation) and (3) cupric ions/ascorbic acid. Oxidation products were identified by spectrometric methods and assessed by reversed-phase HPLC analysis. The photooxidation of UCA was induced by UV-B and UV-C, but not by UV-A radiation. Photooxidation and Fenton oxidation of trans-UCA, as well as of cis-UCA yielded comparable chromatographic patterns of UCA oxidation products. Several of the formed products were identified. The formation of three identified imidazoles was shown in UV-B exposed corneal layer samples, derived from human skin.  相似文献   

19.
Different seafood products based on Peruvian anchoveta (Engraulis ringens) fisheries and freshwater aquaculture of trout (Oncorhynchus mykiss), tilapia (Oreochromis spp.) and black pacu (Colossoma macropomum), contribute at different scales to the socio-economic development, environmental degradation and nutrition of the Peruvian population. Various indicators have been used in the literature to assess the performance of these industries regarding different aspects of sustainability, notably their socio-economic performance. In this study, a novel set of indicators is proposed to evaluate the sustainability performance of these industries in Peru, based on life cycle assessment (LCA) and nutritional profiling, as well as on energy and socio-economic assessment approaches. The emphasis is put on the potential of different products to contribute to improving the nutrition of the Peruvian population in an energy-efficient, environmentally friendly and socio-economically sound way. The set of indicators includes biotic resource use (BRU), cumulative energy demand (CED), energy return on investment (EROI), production costs, gross profit generation, added value, and nutritional profile in terms of vitamins, minerals and essential fatty acids; as well as a number of life cycle impact assessment indicators commonly used in seafood studies, and some recently proposed indicators of resource status (measuring the impacts of fish biomass removal at the species and ecosystem levels). Results suggest that more energy-intensive/highly processed products (cured and canned anchoveta products) represent a higher burden, in terms of environmental impact, than less energy-intensive products (salted and frozen anchoveta products, semi-intensive aquaculture products). This result is confirmed when comparing all products regarding their industrial-to-nutritional energy ratio. Regarding the other attributes analysed, the scoring shows that salted and frozen anchoveta products generate fewer jobs and lower gross profit than canned and cured, while aquaculture products maximise them. Overall, it was concluded that less energy-intensive industries (anchoveta freezing and salting) are the least environmentally impacting but also the least economically interesting products, yet delivering higher nutritional value. Aquaculture products maximise gross profit and job creation, with lower energy efficiency and nutritional values. The proposed set of sustainability indicators fulfilled its goal in providing a multi-criteria assessment of anchoveta direct human consumption and freshwater aquaculture products. As often the case, there is no ideal product and the best trade-off must be sought when making decision regarding fisheries and seafood policy. No threshold for performance of the different indicators is offered, because the goal of the comparison is to contrast the relative performance among products, not of products against reference values.  相似文献   

20.
《Process Biochemistry》2007,42(9):1279-1284
The study focuses on the Reactive Orange 16 (RO16) degradation products obtained by fungal treatment of the dye. Eighty percent of dye decolorization was achieved within 24 h by Irpex lacteus cultures immobilized on polyurethane foam (PUF). Dye degradation products were investigated using LC–MS analysis. Three compounds were identified as the dye intermediates: 6-acetamido-3,4-dioxo-3,4-dihydronaphthalene-2-sulfonate (m/z 294), (E)-2-(4-acetamidophenyl)-1-carboxyethenesulfonate (m/z 284), and 4-(2-hydroxyethylsulfonyl)phenolate (m/z 201). Despite significant laccase activities detected in the fungal cultures, no backward polymerization of the reaction products resulting in recurrent colorization was observed after fungal treatment of the dye solution.  相似文献   

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