Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| selective and sensitive determination of lipoyllysine (protein-bound alpha-lipoic acid) in biological specimens by high-performance liquid chromatography with fluorescence detection. | the direct determination of lipoyllysine (llys) in proteins was carried out by reversed-phase high-performance liquid chromatography with fluorescence (fl) detection. the proteins containing alpha-lipoic acid (la) were first hydrolyzed with several enzymes such as pronase e and subtilisin a. the disulfide bond (-s-s-) in llys liberated from the enzyme digestion was reduced with tris(2-carboxyethyl)phosphine to the thiol form (-sh). the reduced llys was then labeled with ammonium 4-fluoro-2,1,3-b ... | 2008 | 18513542 |
| crystallization of the c14-rotor of the chloroplast atp synthase reveals that it contains pigments. | the atp synthase is one of the most important enzymes on earth as it couples the transmembrane electrochemical potential of protons to the synthesis of atp from adp and inorganic phosphate, providing the main atp source of almost all higher life on earth. during atp synthesis, stepwise protonation of a conserved carboxylate on each protein subunit of an oligomeric ring of 10-15 c-subunits is commonly thought to drive rotation of the rotor moiety (c(10-14)gammaepsilon) relative to stator moiety ( ... | 2008 | 18515064 |
| nonthermal inactivation of escherichia coli k-12 on spinach leaves, using dense phase carbon dioxide. | while the use of some chemical sanitizers is approved for inactivation of microbes on the surfaces of fruits and vegetables, these compounds often degrade product quality with limited improvement in product safety. the application of dense phase carbon dioxide (dpcd, or high-pressure co2) is a nonthermal process for inactivation of foodborne pathogens inoculated into various juices and model solutions. in this work, dpcd was evaluated for its potential to inactivate escherichia coli k-12 inocula ... | 2008 | 18522038 |
| secondary metabolites from nonhost plants affect the motility and viability of phytopathogenic aphanomyces cochlioides zoospores. | the motile zoospores of the damping-off pathogen aphanomyces cochlioides aggregate on host plants (e.g., sugar beet, spinach) guided by the host-specific plant signal cochliophilin a before infection. to assess the potential role of secondary metabolites in nonhost resistance, acetone extracts of 200 nonhost traditional medicinal plants from chinese and bangladeshi origins were tested for the motility behaviour of a. cochlioides zoospores using a particle bioassay method. nearly one third of the ... | 2008 | 18533468 |
| the use of bacterial alkaline phosphatase assay for rapid monitoring of bacterial counts on spinach. | this study was undertaken to evaluate the applicability of bacterial alkaline phosphatase (alp) activity for rapid monitoring of total mesophilic bacteria counts in spinach. a set of fresh and decayed spinach mixtures were tested to rapidly (10 min) monitor spinach bacterial counts. to assay alp activity, lumigen aps-5 was used as a substrate. bovine alp was reduced after heat treatment at 75 degrees c for 1 min; in contrast, bacterial alp activity increased. to differentiate bacterial alp from ... | 2008 | 18577006 |
| dietary flavonoid sources in australian adults. | evidence from laboratory-based in vitro studies provides compelling evidence supporting the involvement of dietary flavonoid intake in human cancer risk. associations between intakes of individual flavonoids and disease outcomes at the population level are emerging from recent epidemiological studies. as an important step in the development of methods to assess flavonoid intakes across populations, the major sources of dietary flavonoids in the adult australian population were identified. data f ... | 2008 | 18584477 |
| anti-tumor effect of orally administered spinach glycolipid fraction on implanted cancer cells, colon-26, in mice. | we succeeded in purifying a major glycolipid fraction from a green vegetable, spinach. this fraction consists mainly of three glycolipids: monogalactosyl diacylglycerol (mgdg), digalactosyl diacylglycerol (dgdg), and sulfoquinovosyl diacylglycerol (sqdg). in a previous study, we found that the glycolipid fraction inhibited dna polymerase activity, cancer cell growth and tumor growth with subcutaneous injection. we aimed to clarify oral administration of the glycolipid fraction, suppressing colon ... | 2008 | 18594894 |
| use of episcopic differential interference contrast microscopy to identify bacterial biofilms on salad leaves and track colonization by salmonella thompson. | zoonotic pathogens such as salmonella can cause gastrointestinal illness if they are ingested with food. foods such as salads pose a greater risk because they are consumed raw and have been the source of major outbreaks of disease from fresh produce. the novel light microscopy methods used in this study allow detailed, high resolution imaging of the leaf surface environment (the phyllosphere) and allow pathogen tracking. episcopic differential interference contrast microscopy coupled with epiflu ... | 2008 | 18177375 |
| polynucleotide phosphorylase and the archaeal exosome as poly(a)-polymerases. | the addition of poly(a)-tails to rna is a phenomenon common to almost all organisms. not only homopolymeric poly(a)-tails, comprised exclusively of adenosines, but also heteropolymeric poly(a)-rich extensions, which include the other three nucleotides as well, have been observed in bacteria, archaea, chloroplasts, and human cells. polynucleotide phosphorylase (pnpase) and the archaeal exosome, which bear strong similarities to one another, both functionally and structurally, were found to polyme ... | 2008 | 18177749 |
| met-arg-trp derived from rubisco lowers blood pressure via prostaglandin d(2)-dependent vasorelaxation in spontaneously hypertensive rats. | met-arg-trp (mrw) has been isolated as an inhibitor for angiotensin i-converting enzyme (ace) from a pepsin-pancreatin digest of spinach ribulose bisphosphate carboxylase/oxygenase (rubisco) (ic(50)=0.6 microm). it has been reported that hypotensive activity of ace-inhibitory peptides derived from food proteins are weakened in spontaneously hypertensive rats older than 25 weeks (old shr). however, mrw reduced blood pressure after oral administration at a dose of 5 mg/kg in old shr as well as in ... | 2008 | 18180074 |
| antioxidant stress is promoted by nano-anatase in spinach chloroplasts under uv-b radiation. | a proven photocatalyst, titanium dioxide in the form of nano-anatase, is capable of undergoing electron transfer reactions under light. in previous studies, we had proven that nano-anatase could absorb ultraviolet light (uv-b) and convert light energy to stable chemistry energy finally via electron transport in spinach chloroplasts. the mechanisms by which nano-anatase promotes antioxidant stress in spinach chloroplasts under uv-b radiation are still not clearly understood. in the present paper, ... | 2008 | 18186002 |
| low bioavailability of dietary epoxyxanthophylls in humans. | epoxyxanthophylls (epoxide-containing xanthophylls), a group of carotenoids, are ubiquitously distributed in edible plants. among them, neoxanthin in green leafy vegetables and fucoxanthin in brown algae have been reported to exhibit an antiproliferative effect on several human cancer cells in vitro. however, there is little information about the intestinal absorption and metabolic fate of dietary epoxyxanthophylls in humans. to estimate the intestinal absorption of neoxanthin and fucoxanthin in ... | 2008 | 18186952 |
| bacteriophage-amplified bioluminescent sensing of escherichia coli o157:h7. | escherichia coli o157:h7 remains a continuous public health threat, appearing in meats, water, fruit juices, milk, cheese, and vegetables, where its ingestion at concentrations of perhaps as low as 10 to 100 organisms can result in potent toxin exposure and severe damage to the lining of the intestine. abdominal pain and diarrhea develop, which in the very young or elderly can progress towards hemolytic uremic syndrome and kidney failure. to assist in the detection of e. coli o157:h7, a recombin ... | 2008 | 18188543 |
| active site and loop 4 movements within human glycolate oxidase: implications for substrate specificity and drug design. | human glycolate oxidase (go) catalyzes the fmn-dependent oxidation of glycolate to glyoxylate and glyoxylate to oxalate, a key metabolite in kidney stone formation. we report herein the structures of recombinant go complexed with sulfate, glyoxylate, and an inhibitor, 4-carboxy-5-dodecylsulfanyl-1,2,3-triazole (cdst), determined by x-ray crystallography. in contrast to most alpha-hydroxy acid oxidases including spinach glycolate oxidase, a loop region, known as loop 4, is completely visible when ... | 2008 | 18215067 |
| microbiological quality of fresh, minimally-processed fruit and vegetables, and sprouts from retail establishments. | a survey of fresh and minimally-processed fruit and vegetables, and sprouts was conducted in several retail establishments in the lleida area (catalonia, spain) during 2005-2006 to determine whether microbial contamination, and in particular potentially pathogenic bacteria, was present under these commodities. a total of 300 samples--including 21 ready-to-eat fruits, 28 whole fresh vegetables, 15 sprout samples and 237 ready-to-eat salads containing from one to six vegetables--were purchased fro ... | 2008 | 18237811 |
| rubimetide (met-arg-trp) derived from rubisco exhibits anxiolytic-like activity via the dp1 receptor in male ddy mice. | in this study, we found that met-arg-trp (rubimetide), which had been isolated as a hypotensive peptide from a pepsin-pancreatin digest of spinach ribulose bisphosphate carboxylase/oxygenase (rubisco), has anxiolytic-like activity in the elevated plus-maze test at a dose of 0.1mg/kg (i.p.) or 1.0mg/kg (p.o.) in mice with p<0.01 and p<0.05, respectively. the anxiolytic-like activity of rubimetide (0.1mg/kg, i.p.) was blocked by bw a868c (60microg/kg, i.p.), an antagonist for the dp1 receptor, sug ... | 2008 | 18243414 |
| optimization and validation of enzyme-linked immunosorbent assay for the determination of endosulfan residues in food samples. | in this study, an enzyme-linked immunosorbent assay (elisa) was optimized and applied to the determination of endosulfan residues in 20 different kinds of food commodities including vegetables, dry fruits, tea and meat. the limit of detection (ic(15)) was 0.8 microg kg(-1) and the sensitivity (ic(50)) was 5.3 microg kg(-1). three simple extraction methods were developed, including shaking on the rotary shaker at 250 r min(-1) overnight, shaking on the rotary shaker for 1 h and thoroughly mixing ... | 2008 | 18246504 |
| flow injection preconcentration system using a new functionalized resin for determination of cadmium and nickel in tobacco samples. | a solid-phase extraction method combined with flow injection (fi) on-line flame atomic absorption spectrometry (faas) for the determination of cadmium and nickel in tobacco samples is presented. the 2-aminothiophenol functionalized amberlite xad-4 (at-xad) resin was synthesized by covalent coupling of the ligand with the copolymer through a methylene group. a minicolumn packed with at-xad was connected into the automated on-line preconcentration system. elution of metal ions from minicolumn can ... | 2008 | 18155353 |
| altered utilization of n-acetyl-d-galactosamine by escherichia coli o157:h7 from the 2006 spinach outbreak. | in silico analyses of previously sequenced strains of escherichia coli o157:h7, edl933 and sakai, localized the gene cluster for the utilization of n-acetyl-d-galactosamine (aga) and d-galactosamine (gam). this gene cluster encodes the aga phosphoenolpyruvate:carbohydrate phosphotransferase system (pts) and other catabolic enzymes responsible for transport and catabolism of aga. as the complete coding sequences for enzyme iia (eiia)(aga/gam), eiib(aga), eiic(aga), and eiid(aga) of the aga pts ar ... | 2008 | 18156259 |
| microbiological quality of bagged cut spinach and lettuce mixes. | analysis of 100 bagged lettuce and spinach samples showed mean total bacterial counts of 7.0 log(10) cfu/g and a broad range of < 4 to 8.3 log10 cfu/g. most probable numbers (mpn) of > or = 11,000/g coliforms were found in 55 samples, and generic escherichia coli bacteria were detected in 16 samples, but no e. coli count exceeded 10 mpn/g. | 2008 | 18156327 |
| effect of x-radiation on lipid peroxidation and antioxidant systems in rats treated with saponin-containing compounds. | the aim of this study was to investigate the effect of three saponin-containing plant species extracts (aesculuc hippocastanum l. seed extract [ahe], medicago sativa l. extract [mse] and spinacia oleracea l. extract [soe]) on lipid peroxidation and on antioxidant systems in rats exposed to x-rays (xr). the rats were divided into three categories. the first category served as controls and received only a standard diet. the second category served as the radiation group and received 5 and 10 gy xr ... | 2008 | 18173726 |
| characterization of shiga toxin-producing escherichia coli isolates associated with two multistate food-borne outbreaks that occurred in 2006. | shiga toxin-producing escherichia coli isolates from two 2006 outbreaks were compared to other o157:h7 isolates for virulence genotype, biofilm formation, and stress responses. spinach- and lettuce-related-outbreak strains had similar pulsed-field gel electrophoresis patterns, and all carried both stx2 and stx2c variant genes. cooperative biofilm formation involving an e. coli o157:h7 strain and a non-o157:h7 strain was also demonstrated. | 2008 | 18083883 |
| ribulose-1,5-bisphosphate carboxylase/oxygenase from thermophilic cyanobacterium thermosynechococcus elongatus. | ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) can be divided into two branches: the "red-like type" of marine algae and the "green-like type" of cyanobacteria, green algae, and higher plants. we found that the "green-like type" rubisco from the thermophilic cyanobacterium thermosynechococcus elongatus has an almost 2-fold higher specificity factor compared with rubiscos of mesophilic cyanobacteria, reaching the values of higher plants, and simultaneously revealing an improvement in e ... | 2008 | 17922215 |
| microbial contamination of fruit and vegetables and the behaviour of enteropathogens in the phyllosphere: a review. | consumption of fruit and vegetable products is commonly viewed as a potential risk factor for infection with enteropathogens such as salmonella and escherichia coli o157, with recent outbreaks linked to lettuce, spinach and tomatoes. routes of contamination are varied and include application of organic wastes to agricultural land as fertilizer, contamination of waters used for irrigation with faecal material, direct contamination by livestock, wild animals and birds and postharvest issues such a ... | 2008 | 17927745 |
| differences in allergenic potential of food extracts following oral exposure in mice reflect differences in digestibility: potential approaches to safety assessment. | an animal model for food allergy is needed to assess genetically modified food crops for potential allergenicity. the ideal model must produce allergic antibody (ige) to proteins differentially according to known allergenicity before being used to accurately identify potential allergens among novel proteins. the oral route is the most relevant for exposure to food antigens, and a protein's stability to digestion is a current risk assessment tool based on this natural route. however, normal labor ... | 2008 | 18033772 |
| remediation of arsenic contaminated soils by iron-oxide application, evaluated in terms of plant productivity, arsenic and phytotoxic metal uptake. | four iron-bearing additives, selected for known or potential ability to adsorb anions, were evaluated for their effectiveness in attenuation of arsenic (as) in three soils with different sources of contamination (canal dredgings, coal fly ash deposits, and low-level alkali waste). amendments used were lime, goethite (alpha-feooh) (crystallised iron oxide) and three iron-bearing additives, iron grit and iron (ii) and (iii) sulphates plus lime, which result in 'de novo' iron oxide formation in soi ... | 2008 | 17964636 |
| genetic engineering of the biosynthesis of glycinebetaine leads to increased tolerance of photosynthesis to salt stress in transgenic tobacco plants. | genetically engineered tobacco (nicotiana tabacum l.) with the ability to synthesis glycinebetaine (gb) in chloroplasts was established by introducing the badh gene for betaine aldehyde dehydrogenase from spinach (spinacia oleracea l.). the genetic engineering resulted in enhanced tolerance of growth of young seedlings to salt stress. this increased tolerance was not due to improved water status, since there were no significant differences in accumulation of sodium and chloride, leaf water poten ... | 2008 | 17975734 |
| reduction of bacteria on spinach, lettuce, and surfaces in food service areas using neutral electrolyzed oxidizing water. | food safety issues and increases in food borne illnesses have promulgated the development of new sanitation methods to eliminate pathogenic organisms on foods and surfaces in food service areas. electrolyzed oxidizing water (eo water) shows promise as an environmentally friendly broad spectrum microbial decontamination agent. eo water is generated by the passage of a dilute salt solution ( approximately 1% nacl) through an electrochemical cell. this electrolytic process converts chloride ions an ... | 2008 | 17993375 |
| assessing risk of heavy metals from consuming food grown on sewage irrigated soils and food chain transfer. | heavy metal pollution of soils resulting from sewage and wastewater irrigation is causing major concern due to the potential risk involved. in the present study musi river and its environs were assessed for heavy metal contamination. the study area was assessed for zn, cr, cu, ni, co and pb in soils, forage grass, milk from cattle, leafy and non-leafy vegetables. partitioning pattern of soil revealed high levels of zn, cr, and cu associated with labile fractions, making them more mobile and plan ... | 2008 | 17555815 |
| element contents and food safety of water spinach (ipomoea aquatica forssk.) cultivated with wastewater in hanoi, vietnam. | extensive aquatic or semi-aquatic production of water spinach (ipomoea aquatica forssk.) for human consumption takes place in southeast asia. the aim of this study was to assess the concentrations of 38 elements in soil and water spinach cultivated under different degrees of wastewater exposure in hanoi, vietnam. the results showed no effect of wastewater use on the overall element concentrations in soil and water spinach. mean soil concentrations for selected potentially toxic elements at the s ... | 2008 | 17593534 |
| use of the physiologically-based extraction test to assess the oral bioaccessibility of metals in vegetable plants grown in contaminated soil. | the oral bioaccessibility of metals in vegetable plants grown on contaminated soil was assessed. this was done using the physiologically-based extraction test (pbet) to simulate the human digestion of plant material. a range of vegetable plants, i.e. carrot, lettuce, radish and spinach, were grown on metal contaminated soil. after reaching maturity the plants were harvested and analysed for their total metal content (i.e. cr, cd, cu, fe, mn, mo, ni, pb and zn) by inductively coupled plasma-mass ... | 2008 | 17601641 |
| differential expression of ribosome-inactivating protein genes during somatic embryogenesis in spinach (spinacia oleracea). | root segments from spinach (spinacia oleracea l. cv. jiromaru) seedlings form embryogenic callus (ec) that responded to exogenous ga(3) by accumulating a 31-kda glycoprotein [bp31 or s. oleracea ribosome-inactivating protein (ec 3.2.2.22) (sorip1)] in association with the expression of embryogenic potential. microsequencing of this protein revealed significant similarity with type 1 rips. we identified cdnas for sorip1 and s. oleracea rip2 (sorip2), a novel rip having a consensus shiga/ricin tox ... | 2008 | 18494862 |
| comparative chloroplast genomics and phylogenetics of fagopyrum esculentum ssp. ancestrale -a wild ancestor of cultivated buckwheat. | chloroplast genome sequences are extremely informative about species-interrelationships owing to its non-meiotic and often uniparental inheritance over generations. the subject of our study, fagopyrum esculentum, is a member of the family polygonaceae belonging to the order caryophyllales. an uncertainty remains regarding the affinity of caryophyllales and the asterids that could be due to undersampling of the taxa. with that background, having access to the complete chloroplast genome sequence ... | 2008 | 18492277 |
| total and individual carotenoids and phenolic acids content in fresh, refrigerated and processed spinach (spinacia oleracea l.). | the carotenoid and phenolic acid contents in fresh, stored and processed (blanched, frozen and boiled) spinach were comparatively determined by spectrophotometric and hplc analyses. the major carotenoids identified after hplc analysis in saponified samples were lutein (37-53μg/kg), β-carotene (18-31μg/kg), violaxanthin (9-23μg/kg) and neoxanthin (10-22μg/kg). these carotenoids were all affected by storage and/or heating. the content of carotenoids was best preserved after storage for one day at ... | 2008 | 26059144 |
| fluoride accumulation in soil and vegetation in the vicinity of brick fields. | fluoride in the soil and vegetation in the vicinity of brick field in the suburb of lucknow, india was estimated. the water soluble fluoride (1:1) in the surface soil ranged from 0.59 ppm to 2.74 ppm where as cacl(2) extractable fluoride ranged from 0.69 ppm to 3.18 ppm. the mean total fluoride concentration in surface soil varied from 322 microg g(-1) to 456 microg g(-1). the local vegetations grown in the area found to accumulate air borne fluoride from the brick field. the fluoride accumulati ... | 2008 | 18345473 |
| investigating biological activity spectrum for novel quinoline analogues 2: hydroxyquinolinecarboxamides with photosynthesis-inhibiting activity. | two series of amides based on quinoline scaffold were designed and synthesized in search of photosynthesis inhibitors. the compounds were tested for their photosynthesis-inhibiting activity against spinacia oleracea l. and chlorella vulgaris beij. the compounds lipophilicity was determined by the rp-hplc method. several compounds showed biological activity similar or even higher than that of the standard (dcmu). the structure-activity relationships are discussed. | 2008 | 18342517 |
| phosphorylation-dependent regulation of excitation energy distribution between the two photosystems in higher plants. | phosphorylation-dependent movement of the light-harvesting complex ii (lhcii) between photosystem ii (psii) and photosystem i (psi) takes place in order to balance the function of the two photosystems. traditionally, the phosphorylatable fraction of lhcii has been considered as the functional unit of this dynamic regulation. here, a mechanical fractionation of the thylakoid membrane of spinacia oleracea was performed from leaves both in the phosphorylated state (low light, ll) and in the dephosp ... | 2008 | 18331820 |
| protein diffusion and macromolecular crowding in thylakoid membranes. | the photosynthetic light reactions of green plants are mediated by chlorophyll-binding protein complexes located in the thylakoid membranes within the chloroplasts. thylakoid membranes have a complex structure, with lateral segregation of protein complexes into distinct membrane regions known as the grana and the stroma lamellae. it has long been clear that some protein complexes can diffuse between the grana and the stroma lamellae, and that this movement is important for processes including me ... | 2008 | 18287489 |
| differences in the metabolite profiles of spinach (spinacia oleracea l.) leaf in different concentrations of nitrate in the culture solution. | the nitrogen (n) status of a plant determines the composition of its major components (amino acids, proteins, carbohydrates and organic acids) and, directly or indirectly, affects the quality of agricultural products in terms of their calorific value and taste. although these effects are guided by changes in metabolic pathways, no overall metabolic analysis has previously been conducted to demonstrate such effects. here, metabolite profiling using gas chromatography-mass spectrometry (gc-ms) was ... | 2008 | 18089581 |
| laurdan fluorescence spectroscopy in the thylakoid bilayer: the effect of violaxanthin to zeaxanthin conversion on the galactolipid dominated lipid environment. | laurdan (6-lauroyl-2-dimethylaminonaphthalene) fluorescence spectroscopy has been applied to probe the physical status of the thylakoid membrane upon conversion of violaxanthin to zeaxanthin. so far, only phospholipid-dominated membranes have been studied by this method and hereby we report the first use of laurdan in mono- and digalactosyldiacylglycerol-dominated membrane systems. the generalised polarisation (gp) of laurdan was used as a measure of the structural effect of xanthophyll cycle pi ... | 2008 | 17980143 |
| comparative metabolism and pharmacokinetics of seven neonicotinoid insecticides in spinach. | the metabolism of seven commercial neonicotinoid insecticides was compared in spinach seedlings (spinacia oleracea) using hplc-dad and lc-msd to analyze the large number and great variety of metabolites. the parent neonicotinoid levels in the foliage following hydroponic treatment varied from differences in uptake and persistence. the metabolic reactions included nitro reduction, cyano hydrolysis, demethylation, sulfoxidation, imidazolidine and thiazolidine hydroxylation and olefin formation, ox ... | 2008 | 18922014 |
| ecdysteroids in spinach (spinacia oleracea l.): biosynthesis, transport and regulation of levels. | many plant species produce phytoecdysteroids (pes: i.e. analogues of insect steroid hormones). there is increasing evidence that pes are used as a chemical defence by plants against non-adapted insects and nematodes. pes are good candidates for the development of an environmentally safe approach to crop protection. most crop species do not accumulate pes. however, many arguments support the idea that most, if not all, plant species have the genetic ability to produce pes, but the biosynthetic pa ... | 2008 | 18653353 |
| response of spinach (spinacea oleracea) to the added fluoride in an alkaline soil. | the influence of soil contamination by inorganic fluoride (naf) on the uptake and accumulation of fluoride in the shoot and root of spinach (spinacea oleracea) was investigated in pot experiment under controlled conditions. the soluble fluoride in soil varied between 2.57 mgkg(-1) soil and 16.44 mgkg(-1) soil in the treatment range of 0-800 mgnaf kg(-1) soil. it was found that the concentration of the total fluoride in shoot and root varied between 23.5 mgkg(-1) dry wt. (control) and 219.8 mgkg( ... | 2008 | 18639373 |
| involvement of extracellular cu/zn superoxide dismutase in cotton fiber primary and secondary cell wall biosynthesis. | extracellular cu/zn superoxide dismutases (csds) that catalyze the conversion of superoxide to hydrogen peroxide have been suggested to be involved in lignification of secondary walls in spinach, pine and aspen. in cotton fibers, hydrogen peroxide was proposed to be involved in the induction of secondary cell wall biosynthesis. recently, we identified extracellular csds from developing cotton fibers using both immunological and epitope tagging techniques. since cotton fibers are not lignified, w ... | 2008 | 19704453 |
| metabolic fate of [14c] chlorophenols in radish (raphanus sativus), lettuce (lactuca sativa), and spinach (spinacia oleracea). | chlorophenols are potentially harmful pollutants that are found in numerous natural and agricultural systems. plants are a sink for xenobiotics, which occur either intentionally or not, as they are unable to eliminate them although they generally metabolize them into less toxic compounds. the metabolic fate of [ (14)c] 4-chlorophenol (4-cp), [ (14)c] 2,4-dichlorophenol (2,4-dcp), and [ (14)c] 2,4,5-trichlorophenol (2,4,5-tcp) was investigated in lettuce, spinach, and radish to locate putative to ... | 2008 | 18763782 |
| nitrogen nutrition and antioxidant metabolism in ammonium-tolerant and -sensitive plants. | ammonium nutrition is of interest as an alternative to that of using nitrate. however, the former has been reported as stressful to many plant species especially to some important crops, as most abiotic stresses may trigger oxidative imbalances in plants. in this work, we investigate the response of oxidative metabolism of two plant species, spinach (spinacia oleracea l. cv. gigante de invierno) and pea (pisum sativum l. cv. rondo), which have distinct tolerance to ammonium. plants were grown in ... | 2008 | 18275467 |
| conventional crops and organic amendments for pb, cd and zn treatment at a severely contaminated site. | the ability of selected plants and amendments to treat pb, cd and zn accumulations from a metalliferous waste disposal site was studied both in the greenhouse and field. spinach (spinacea oleracea), cabbage (brassica oleracea), and a grass-legume mix (red fescue, festuca rubra; ryegrass, lolium perenne); and bean (vicia faba) were grown in the greenhouse on blast furnace slag or baghouse dust amended with composted peat (cp). all plant species accumulated pb, cd and zn to varying degrees. total ... | 2008 | 17475483 |
| composition of the phyllospheric microbial populations on vegetable plants with different glucosinolate and carotenoid compositions. | the plant phyllosphere is intensely colonized by a complex and highly diverse microbial population and shows pronounced plant-species-specific differences. the mechanisms and influencing factors determining whether and in which density microorganisms colonize plant phyllosphere tissues are not yet fully understood. one of the key influencing factors is thought to be phytochemical concentration and composition. therefore, correlations between various concentrations of individual glucosinolates an ... | 2008 | 18183453 |
| the biochemistry of rubisco in flaveria. | c(4) plants have been reported to have rubiscos with higher maximum carboxylation rates (kcat(co(2))) and michaelis-menten constants (k(m)) for co(2) (k(c)) than the enzyme from c(3) species, but variation in other kinetic parameters between the two photosynthetic pathways has not been extensively examined. the co(2)/o(2) specificity (s(c/o)), kcat(co(2)), k(c), and the k(m) for o(2) (k(o)) and rubp (k(m-rubp)), were measured at 25 degrees c, in rubisco purified from 16 species of flaveria (aste ... | 2008 | 18227079 |
| heterogeneous photocatalytic disinfection of wash waters from the fresh-cut vegetable industry. | the effectiveness of photocatalytic disinfection for control of natural and potentially pathogenic microflora in wash waters used for fresh-cut vegetables was evaluated. wash waters for lettuce, escarole, chicory, carrot, onion, and spinach from a fresh-cut vegetable processing plant were treated with a titanium dioxide (tio2) photocatalytic system. the vegetable wash waters were impelled out with a pump at a flow rate of 1,000 liters/h and conducted through a stainless steel circuit to the filt ... | 2008 | 18326177 |
| nutritional quality of some wild leafy vegetables in south africa. | wild vegetables play an important role in the diet of inhabitants of different parts of the world. among the wild vegetables of south africa are chenopodium album, sonchus asper, solanumnigrum and urtica urens. the leaves of these plants were analysed for their nutritive value, anti-nutritive components and polyphenolic contents. the protein contents of their leaves ranged between 13.25% and 26.44%, while the fibre and mineral (ash) contents were 16.08-23.08% and 13.0-27.75%, respectively. u. ur ... | 2009 | 19037794 |
| dry deposition of gaseous radioiodine and particulate radiocaesium onto leafy vegetables. | radionuclides released to the atmosphere during dry weather (e.g. after a nuclear accident) may contaminate vegetable foods and cause exposure to humans via the food chain. to obtain experimental data for an appropriate assessment of this exposure path, dry deposition of radionuclides to leafy vegetables was studied under homogeneous and controlled greenhouse conditions. gaseous (131)i-tracer in predominant elemental form and particulate (134)cs-tracer at about 1 mum diameter were used to identi ... | 2009 | 19640563 |
| defining the far-red limit of photosystem ii in spinach. | the far-red limit of photosystem ii (psii) photochemistry was studied in psii-enriched membranes and psii core preparations from spinach (spinacia oleracea) after application of laser flashes between 730 and 820 nm. light up to 800 nm was found to drive psii activity in both acceptor side reduction and oxidation of the water-oxidizing camn(4) cluster. far-red illumination induced enhancement of, and slowed down decay kinetics of, variable fluorescence. both effects reflect reduction of the accep ... | 2009 | 19700631 |
| bioaccumulation of heavy metals and two organochlorine pesticides (ddt and bhc) in crops irrigated with secondary treated waste water. | four crop plants oryza sativa (rice), solanum melongena (brinjal), spinacea oleracea (spinach) and raphanus sativus (radish) were grown to study the impact of secondary treated municipal waste water irrigation. these plants were grown in three plots each of 0.5 ha, and irrigated with secondary treated waste water from a sewage treatment plant. sludge from the same sewage treatment plant was applied as manure. cultivated plants were analyzed for accumulation of heavy metals and pesticides. result ... | 2009 | 18654831 |
| phytoecdysteroid c2-hydroxylase is microsomal in spinach, spinacia oleracea l. | an enzyme involved in the biosynthesis of phytoecdysteroids, the c2-hydroxylase, has been investigated in spinach, spinacia oleracea. this enzyme is microsomal and its k(m) has been determined using 2-deoxy-20-hydroxyecdysone as substrate (k(m)=3.72 microm). it is much more efficient with 2-deoxy-20-hydroxyecdysone than with 2-deoxyecdysone and, conversely, the c20-hydroxylase is more active on 2-deoxyecdysone than on ecdysone. these data support the conclusion that c20-hydroxylation precedes c2 ... | 2009 | 19750551 |
| investigating the foliar uptake and within-leaf migration of phenanthrene by moss (hypnum cupressiforme) using two-photon excitation microscopy with autofluorescence. | mosses have the potential to play a significant role in the global cycling and fate of semivolatile organic compounds (svocs), due to their extensive distribution at high latitudes and the long-range atmospheric transport of svocs. unlike vascular plants mosses lack a substantial cuticle, vascular system, or root structure, taking up water, nutrients and svocs primarily from the atmosphere. mosses have thus been effectively used as passive air samplers for many svocs in urban and rural locations ... | 2009 | 19731673 |
| evaluation of the toxicity of stress-related aldehydes to photosynthesis in chloroplasts. | aldehydes produced under various environmental stresses can cause cellular injury in plants, but their toxicology in photosynthesis has been scarcely investigated. we here evaluated their effects on photosynthetic reactions in chloroplasts isolated from spinacia oleracea l. leaves. aldehydes that are known to stem from lipid peroxides inactivated the co(2) photoreduction to various extents, while their corresponding alcohols and carboxylic acids did not affect photosynthesis. alpha,beta-unsatura ... | 2009 | 19578873 |
| increase of ascorbic acid content and nutritional quality in spinach leaves during physiological acclimation to low temperature. | the effect of acclimation to 10 degrees c on the leaf content of ascorbic and oxalic acids, was investigated in spinach (spinacia oleracea l.). at 10 degrees c the content of ascorbic acid in leaves increased and after 7 days it was about 41% higher than in plants remaining under a 25 degrees c/20 degrees c day/night temperature regime. in contrast, the content of oxalate, remained unchanged. transfer to 10 degrees c increased the ascorbic but not the oxalic acid content of the leaf intercellula ... | 2009 | 19376730 |
| ring-substituted 4-hydroxy-1h-quinolin-2-ones: preparation and biological activity. | in the study, a series of twelve ring-substituted 4-hydroxy-1h-quinolin-2-one derivatives were prepared. the procedures for synthesis of the compounds are presented. the compounds were analyzed using rp-hplc to determine lipophilicity and tested for their photosynthesis-inhibiting activity using spinach (spinacia oleracea l.) chloroplasts. all the synthesized compounds were also evaluated for antifungal activity using in vitro screening with eight fungal strains. for all the compounds, the relat ... | 2009 | 19305366 |
| does the different proteomic profile found in apical and basal leaves of spinach reveal a strategy of this plant toward cadmium pollution response? | chlorosis develops in spinacia oleracea l. plants exposed to cd and is prevalently localized in the basal leaves. a proteomic comparison of basal and apical leaves from cd-treated plants showed modified profiles that are different and complementary in the two locations. total chlorophyll increased in apical leaves as did photosynthetic complexes and enzymes involved in co2 fixation and carbohydrate metabolism. thus, apical leaves seem to supply the plant's energy requirements and, consistent wit ... | 2009 | 19290619 |
| kunitz-type trypsin inhibitor with high stability from spinacia oleracea l. seeds. | the trypsin inhibitor soti was isolated from spinacia oleracea l. seeds through ammonium sulfate precipitation, sepharose 4b-trypsin affinity chromatography, and sephadex g-75 chromatography. this typical kunitz inhibitor showed remarkable stability to heat, ph, and denaturant. it retained 80% of its activity against trypsin after boiling for 20 min, and more than 90% activity when treated with 6 m guanidine hydrochloride. the formation of stable soti-trypsin complex (k(i) = 2.3x10(-6) m) is con ... | 2009 | 19232057 |
| transcriptional control of two ribosome-inactivating protein genes expressed in spinach (spinacia oleracea) embryos. | sorip1 and sorip2 are ribosome-inactivating protein (rip: ec 3.2.2.22) genes identified in spinach (spinacia oleracea). they are differentially expressed in a development-dependent manner during spinach somatic embryogenesis. here, we isolated genomic clones of sorip1 and sorip2. these two rip genes have different genomic organization. phylogenetic analysis of predicted amino acid sequences of rips in caryophyllales plants revealed that they are divided into two major subfamilies, corresponding ... | 2009 | 19195903 |
| proteomic analysis of multiprotein complexes in the thylakoid membrane upon cadmium treatment. | the time course of the thylakoid membranes proteomic profile changes upon cadmium (cd) addition to hydroponic spinacia oleracea l. plants has been investigated. two different proteomic approaches have been used: blue native gel electrophoresis followed by sds-page (2d bn-sds-page) and sucrose density gradient ultracentrifugation followed by rp-hplc. chlorophyll (chl) and xanthophylls concentrations, together with esr and real time pcr measurements, were also performed to get a complete overview ... | 2009 | 19035790 |
| accumulation of 2-c-methyl-d-erythritol 2,4-cyclodiphosphate in illuminated plant leaves at supraoptimal temperatures reveals a bottleneck of the prokaryotic methylerythritol 4-phosphate pathway of isoprenoid biosynthesis. | metabolic profiling using phosphorus nuclear magnetic resonance ((31)p-nmr) revealed that the leaves of different herbs and trees accumulate 2-c-methyl-d-erythritol 2,4-cyclodiphosphate (mecdp), an intermediate of the methylerythritol 4-phosphate (mep) pathway, during bright and hot days. in spinach (spinacia oleracea l.) leaves, its accumulation closely depended on irradiance and temperature. mecdp was the only (31)p-nmr-detected mep pathway intermediate. it remained in chloroplasts and was a s ... | 2009 | 19021881 |
| duplication of ap1 within the spinacia oleracea l. ap1/ful clade is followed by rapid amino acid and regulatory evolution. | the ap1/ful clade of mads box genes have undergone multiple duplication events among angiosperm species. while initially identified as having floral meristem identity and floral organ identity function in arabidopsis, the role of ap1 homologs does not appear to be universally conserved even among eudicots. in comparison, the role of fruitfull has not been extensively explored in non-model species. we report on the isolation of three ap1/ful genes from cultivated spinach, spinacia oleracea l. two ... | 2009 | 19005675 |
| air-borne heavy metal contamination to dietary vegetables: a case study from india. | contamination of edible parts of three dietary vegetables, spinach (spinacia oleracea l.), radish (raphanus sativus l.), and tomato (lycopersicon esculentum mill.) by air-borne cadmium (cd), chromium (cr), copper (cu), nickel (ni), and lead (pb) was determined using pot culture experiments at three sites in the city of varanasi, india. the data revealed that although cr and cu in vegetables remained below their safe limits, about 68% of the total samples contained cd, ni, and pb above their resp ... | 2009 | 19771380 |
| kinetic thermal degradation of vitamin c during microwave drying of okra and spinach. | in this present study, the effect of microwave output power and sample amount on vitamin c loss in okra (hibiscus esculenta l.) and spinach (spinacia oleracea l.) were investigated using the microwave drying technique. the procedure is based on the reaction between l-ascorbic acid (vitamin c) and 2,6-dichloroindophenol. the proposed method was applied successfully to both okra and spinach for the determination of ascorbic acid (vitamin c) content. it was observed that as the microwave output pow ... | 2009 | 17886082 |
| escherichia coli o157:h7 stress and virulence gene expression on romaine lettuce using comparative real-time pcr. | foodborne outbreaks attributed to the contamination of fresh produce with escherichia coli o157:h7 are a growing concern. in particular, leafy-green vegetables, including lettuce and spinach, are susceptible to contamination by irrigation water, manure, and food processing and storage practices. the survival of e. coli o157:h7 and natural microflora on romaine lettuce stored at 4 degrees c and 15 degrees c over a 9-day period was evaluated by plate counts. a two-step reverse-transcription compar ... | 2009 | 19248811 |
| multistate outbreak of escherichia coli o157:h7 infection associated with consumption of packaged spinach, august-september 2006: the wisconsin investigation. | escherichia coli o157:h7 infection often causes hemorrhagic colitis and hemolytic uremic syndrome. | 2009 | 19265476 |
| biofunctionalized magnetic nanoparticle integrated mid-infrared pathogen sensor for food matrixes. | magnetic nanoparticles functionalized with anti-escherichia coli o157:h7 or anti-salmonella typhimurium antibodies that can specifically bind to their target organisms were used to isolate e. coli o157:h7 and s. typhimurium separately from a cocktail of bacteria and from food matrixes. the pathogens were then detected using label-free ir fingerprinting. the binding and detection protocol was first validated using a benchtop ft-ir spectrometer and then applied to a portable mid-ir spectrometer to ... | 2009 | 19281189 |
| thylakoids promote release of the satiety hormone cholecystokinin while reducing insulin in healthy humans. | the effects of a promising new appetite suppressor named "thylakoids" (membrane proteins derived from spinach leaves) were examined in a single meal in man. thylakoids inhibit the lipase/colipase hydrolysis of triacylglycerols in vitro and suppress food intake, decrease body-weight gain and raise the satiety hormone cholecystokinin (cck) in rats, but their effects in man remain unclear. the aim of this study was to investigate whether thylakoids, when added to a test meal, affect appetite regula ... | 2009 | 19308799 |
| [estimation of the daily intake of nitrate based on analysis of total diet samples]. | the concentrations of nitrates in total diet samples prepared at 11 places were determined according to the market basket method, and the daily intake of nitrates was estimated based on the analysis results. the mean estimated daily intake of nitrates was 200 mg/man/day (4.0 mg/kg/day) and exceeded the adi (3.7 mg/kg/day) set by the jecfa by 8%. the principal sources of the nitrates were colored vegetables (7th food group) and other vegetables, seaweeds and mushrooms (8th food group), and the in ... | 2009 | 19325223 |
| gene expression induced in escherichia coli o157:h7 upon exposure to model apple juice. | escherichia coli o157:h7 has caused serious outbreaks of food-borne illness via transmission in a variety of food vehicles, including unpasteurized apple juice, dried salami, and spinach. to understand how this pathogen responds to the multiple stresses of the food environment, we compared global transcription patterns before and after exposure to model apple juice. transcriptomes of mid-exponential- and stationary-phase cells were evaluated after 10 min in model apple juice (ph 3.5) using micro ... | 2009 | 19346340 |
| evaluation of treatments for elimination of foodborne pathogens on the surface of leaves and roots of lettuce (lactuca sativa l.). | several outbreaks of salmonella and escherichia coli o157:h7 infections have been associated with consumption of leafy greens. questions remain concerning the ability of these pathogens to become internalized within lettuce and spinach tissues. an effective validated surface disinfection method for lettuce is needed before factors affecting internalization of pathogens can be studied. the objective of this study was to develop a surface disinfection method for lettuce leaves and roots. iceberg l ... | 2009 | 19350966 |
| a microbiological survey of selected alberta-grown fresh produce from farmers' markets in alberta, canada. | previously there was no available information on the levels of indicator bacteria and the prevalence of pathogens in fresh produce grown in alberta, canada. baseline information on the occurrence and levels of escherichia coli and the prevalence of foodborne pathogens in selected produce items available to consumers from farmers' and public markets in two large urban centers and surrounding areas in alberta was obtained. a total of 10 large markets with between 1 and 12 produce vendors and 26 sm ... | 2009 | 19350990 |
| conformational changes in a plant ketol-acid reductoisomerase upon mg(2+) and nadph binding as revealed by two crystal structures. | ketol-acid reductoisomerase (kari; ec 1.1.1.86) is an enzyme in the branched-chain amino acid biosynthesis pathway where it catalyzes the conversion of 2-acetolactate into (2r)-2,3-dihydroxy-3-isovalerate or the conversion of 2-aceto-2-hydroxybutyrate into (2r,3r)-2,3-dihydroxy-3-methylvalerate. kari catalyzes two reactions-alkyl migration and reduction-and requires mg(2+) and nadph for activity. to date, the only reported structures for a plant kari are those of the spinach enzyme-mn(2+)-(phosp ... | 2009 | 19362563 |
| detection of live salmonella sp. cells in produce by a taqman-based quantitative reverse transcriptase real-time pcr targeting inva mrna. | salmonella enterica contamination in foods is a significant concern for public health. when dna detection methods are used for analysis of foods, one of the major concerns is false-positive results from the detection of dead cells. to circumvent this crucial issue, a taqman quantitative real-time rt-pcr (qrt-pcr) assay with an rna internal control was developed. inva rna standards were used to determine the detection limit of this assay as well as to determine inva mrna levels in mid-exponential ... | 2009 | 19376910 |
| is the cry1ab protein from bacillus thuringiensis (bt) taken up by plants from soils previously planted with bt corn and by carrot from hydroponic culture? | the uptake of the insecticidal cry1ab protein from bacillus thuringiensis (bt) by various crops from soils on which bt corn had previously grown was determined. in 2005, the cry1ab protein was detected by western blot in tissues (leaves plus stems) of basil, carrot, kale, lettuce, okra, parsnip, radish, snap bean, and soybean but not in tissues of beet and spinach and was estimated by enzyme-linked immunosorbent assay (elisa) to be 0.05 +/- 0.003 ng g(-1) of fresh plant tissue in basil, 0.02 +/- ... | 2009 | 19444360 |
| production of biofilm and quorum sensing by escherichia coli o157:h7 and its transfer from contact surfaces to meat, poultry, ready-to-eat deli, and produce products. | multistate outbreaks of escherichia coli o157:h7 infections through consumption of contaminated foods including produce products have brought a great safety concern. the objectives of this study were to determine the effect of biofilm and quorum sensing production on the attachment of e. coli o157:h7 on food contact surfaces and to evaluate the transfer of the pathogen from the food contact to various food products. e. coli o157:h7 produced maximum levels of ai-2 signals in 12 h of incubation in ... | 2009 | 19465248 |
| evaluating the effect of environmental factors on pathogen regrowth in compost extract. | pathogenic microorganisms may survive the composting process in low numbers and subsequently regrow to high levels under favorable conditions. the objective of this study was to investigate the regrowth potential of salmonella spp., escherichia coli o157:h7, and listeria monocytogenes in dairy-based composts under different environmental conditions. water extract of commercially available dairy compost was used as a model system. cocktails of five rifampin-resistant strains of each pathogen prev ... | 2009 | 19468701 |
| the effect of pre-treatment and sonication of centrifugal ultrafiltration devices on virus recovery. | enteric viruses such as norovirus (nv) and hepatitis a (hav) are responsible for a large proportion of food and water-borne illnesses. most human pathogenic enteric viruses cannot be cultured so they must be detected by molecular techniques. male specific (f(+)) rna coliphages, a potential surrogate for human enteric viruses, can be detected by culture and molecular assays. numbers of viruses and f-rna coliphages in contaminated food or water may be too low for direct detection. ultrafiltration ... | 2009 | 19555721 |
| in silico genomic analyses reveal three distinct lineages of escherichia coli o157:h7, one of which is associated with hyper-virulence. | many approaches have been used to study the evolution, population structure and genetic diversity of escherichia coli o157:h7; however, observations made with different genotyping systems are not easily relatable to each other. three genetic lineages of e. coli o157:h7 designated i, ii and i/ii have been identified using octamer-based genome scanning and microarray comparative genomic hybridization (mcgh). each lineage contains significant phenotypic differences, with lineage i strains being the ... | 2009 | 19563677 |
| analysis of the genome of the escherichia coli o157:h7 2006 spinach-associated outbreak isolate indicates candidate genes that may enhance virulence. | in addition to causing diarrhea, escherichia coli o157:h7 infection can lead to hemolytic-uremic syndrome (hus), a severe disease characterized by hemolysis and renal failure. differences in hus frequency among e. coli o157:h7 outbreaks have been noted, but our understanding of bacterial factors that promote hus is incomplete. in 2006, in an outbreak of e. coli o157:h7 caused by consumption of contaminated spinach, there was a notably high frequency of hus. we sequenced the genome of the strain ... | 2009 | 19564389 |
| fluorescence measurement by a streak camera in a single-photon-counting mode. | we describe here a recently developed fluorescence measurement system that uses a streak camera to detect fluorescence decay in a single photon-counting mode. this system allows for easy measurements of various samples and provides 2d images of fluorescence in the wavelength and time domains. the great advantage of the system is that the data can be handled with ease; furthermore, the data are amenable to detailed analysis. we describe the picosecond kinetics of fluorescence in spinach photosyst ... | 2009 | 19568951 |
| the endogenous level of ga(1) is upregulated by high temperature during stem elongation in lettuce through lsga3ox1 expression. | bolting of lettuce is promoted by high temperatures. gibberellins (gas) play an important role in the bolting of several plant species, and it has been reported that exogenous gas induce bolting and early flowering in lettuce. to clarify the role of gas in this process, we examined the expression of genes involved in ga metabolism (lsga20ox-1 and -2, lsga3ox-1 and -2, and lsga2ox-1 and -2) and endogenous gas in lettuce stems. quantitative reverse-transcription pcr indicated that the expression o ... | 2009 | 19576660 |
| iron bioavailability of rats fed liver, lentil, spinach and their mixtures. | to study the effects of dietary iron source (basal diet-feso4 x 7h2o, liver, lentil, spinach, liver + lentil, liver+spinach and lentil+spinach) on iron bioavailability, fifty-six albino sprague dawley derived male 21 days old rats were fed on iron-deficient diet (7.8 mg fe kg(-1) diet) and the mentioned seven iron containing diets (40 mg fe kg(-1) diet) for 10 days. rats fed liver diet showed higher iron apparent absorption (52.1%), hemoglobin (hb) gain (0.94 g/100 ml), hb-iron gain (1.2 mg), hb ... | 2009 | 19579971 |
| recent advances in the microbial safety of fresh fruits and vegetables. | foodborne illness outbreaks linked to fresh produce are becoming more frequent and widespread. high impact outbreaks, such as that associated with spinach contaminated with escherichia coli o157:h7, resulted in almost 200 cases of foodborne illness across north america and >$300 m market losses. over the last decade there has been intensive research into gaining an understanding on the interactions of human pathogens with plants and how microbiological safety of fresh produce can be improved. th ... | 2009 | 19595387 |
| prevalence of salmonella in vegetables from mexico. | the present study is an overview of the role of vegetables as a transmission vehicle of salmonella in mexico. one hundred samples of each of 17 different vegetables were analyzed during a period of 18 months. salmonella was isolated from 98 samples. salmonella enterica serovar typhimurium was isolated from the highest percentage of samples with typeable salmonella isolates (23.9%), followed by s. enterica subsp. arizonae and salmonella choleraesuis each from 16.9%, salmonella gallinarum from 11. ... | 2009 | 19610340 |
| government as biosecurity communicator: the 2006 spinach advisory. | in 2006, after the united states food and drug administration (fda) traced escherichia coli o157:h7 cases to spinach, the fda went beyond communicating with consumers and enlisted the cooperation of the food industry to prevent further spinach consumption. understanding the factors that increased or frustrated industry participation provides lessons for communicating about accidental contamination and intentional attacks on the american food supply. this qualitative research about fda's risk com ... | 2009 | 19634999 |
| a comparative study of the extractability of arsenic species from silverbeet and amaranth vegetables. | there is still no reliable standard extraction method for the speciation of arsenic (as) in plant tissue, and hence there is great interest in developing one for plants that are used as human food. speciation and bioavailability are critical for accurate human health risk assessment, as as species vary in both their toxicity and bioavailability. recent incidences of as poisoning in many countries have led to significant research into the fate and dynamics of as in the soil and water environment, ... | 2009 | 19125339 |
| studies of interaction of homo-dimeric ferredoxin-nad(p)+ oxidoreductases of bacillus subtilis and rhodopseudomonas palustris, that are closely related to thioredoxin reductases in amino acid sequence, with ferredoxins and pyridine nucleotide coenzymes. | ferredoxin-nadp(+) oxidoreductases (fnrs) of bacillus subtilis (yumc) and rhodopseudomonas palustris cga009 (rpa3954) belong to a novel homo-dimeric type of fnr with high amino acid sequence homology to nadph-thioredoxin reductases. these fnrs were purified from expression constructs in escherichia coli cells, and their steady-state reactions with [2fe-2s] type ferredoxins (fds) from spinach and r. palustris, [4fe-4s] type fd from b. subtilis, nad(p)(+)/nad(p)h and ferricyanide were studied. fro ... | 2009 | 19162251 |
| replacement of chlorophyll with di-vinyl chlorophyll in the antenna and reaction center complexes of the cyanobacterium synechocystis sp. pcc 6803: characterization of spectral and photochemical properties. | chlorophyll (chl) a in a cyanobacterium synechocystis sp. pcc 6803 was replaced with di-vinyl (dv)-chl a by knock-out of the specific gene (slr1923), responsible for the reduction of a 8-vinyl group, and optical and photochemical properties of purified photosystem (ps) ii complexes (dv-ps ii) were investigated. we observed differences in the peak wavelengths of absorption and fluorescence spectra; however, replacement of chl a with dv-chl a had limited effects. on the contrary, photochemical rea ... | 2009 | 19168027 |
| disulphide proteomes and interactions with thioredoxin on the track towards understanding redox regulation in chloroplasts and cyanobacteria. | light-dependent disulphide/dithiol exchange catalysed by thioredoxin is a classical example of redox regulation of chloroplast enzymes. recent proteome studies have mapped thioredoxin target proteins in all chloroplast compartments ranging from the envelope to the thylakoid lumen. progress in the methodologies has made it possible to identify which cysteine residues interact with thioredoxin and to tackle membrane-bound thioredoxin targets. to date, more than hundred targets of thioredoxin and g ... | 2009 | 19185068 |
| crystallization and preliminary crystallographic characterization of the extrinsic psbp protein of photosystem ii from spinacia oleracea. | preliminary x-ray diffraction analysis of the extrinsic psbp protein of photosystem ii from spinach (spinacia oleracea) was performed using n-terminally his-tagged recombinant psbp protein overexpressed in escherichia coli. recombinant psbp protein (thrombin-digested recombinant his-tagged psbp) stored in bis-tris buffer ph 6.00 was crystallized using the sitting-drop vapour-diffusion technique with peg 550 mme as a precipitant and zinc sulfate as an additive. sds-page analysis of a dissolved cr ... | 2009 | 19193998 |
| osmoregulated periplasmic glucans are needed for competitive growth and biofilm formation by salmonella enterica serovar typhimurium in leafy-green vegetable wash waters and colonization in mice. | osmoregulated periplasmic glucans (opgs) are major periplasmic constituents of gram-negative bacteria. the role of opgs has been postulated in symbiotic as well as pathogenic host-microorganism interactions. here, we report the role of opgs from salmonella enterica serovar typhimurium during growth and biofilm formation in leafy-green vegetable wash water. the opggh mutant strain, which was defective in opg biosynthesis, initiated the growth at a slower rate in wash waters obtained from spinach, ... | 2009 | 19222578 |
| new insights into the catalytic cycle of plant nitrite reductase. electron transfer kinetics and charge storage. | nitrite reductase, which reduces nitrite to ammonium in a six-electron reaction, was characterized through kinetic analysis of an electron transfer cascade involving photoexcited photosystem i and ferredoxin. this cascade was studied at physiological ph by flash-absorption spectroscopy. two different forms of the enzyme were studied: one isolated from spinach leaf and one histidine-tagged recombinant form. when the enzyme is oxidized in the absence of nitrite, single-enzyme reduction leads mostl ... | 2009 | 19226104 |
| a statistical analysis to assess the maturity and stability of six composts. | despite the long-time application of organic waste derived composts to crops, there is still no universally accepted index to assess compost maturity and stability. the research presented in this article investigated the suitability of seven types of seeds for use in germination bioassays to assess the maturity and phytotoxicity of six composts. the composts used in the study were derived from cow manure, sea weeds, olive pulp, poultry manure and municipal solid waste. the seeds used in the germ ... | 2009 | 19117746 |
| identifying efficacious approaches to chemoprevention with chlorophyllin, purified chlorophylls and freeze-dried spinach in a mouse model of transplacental carcinogenesis. | the carcinogenic potential of dibenzo[a,l]pyrene (dbp) has been well characterized in numerous animal models. we have previously documented that a single dose of 15 mg/kg dbp to pregnant mice late in gestation (gd 17) produces an aggressive t-cell lymphoma as well as lung and liver cancer in offspring. the current study examines the chemopreventative properties of chlorophyllin (chl) and chlorophyll (chl) in this transplacental carcinogenesis model. pregnant b6129sf1 females, bred to 129s1/svim ... | 2009 | 19073876 |
| utility of rodent models for evaluating protein allergenicity. | animal models are needed to assess novel proteins produced through biotechnology for potential dietary allergenicity. the exact characteristics that give certain foods allergenic potential are unclear, but must include both the potential to sensitize (induce ige) as well as the capacity to avoid induction of oral tolerance (specific inhibition of ige production). epa has developed two complementary mouse models; one which distinguishes allergenic from non-allergenic food extracts using oral sens ... | 2009 | 18957311 |
| interaction of salmonella enterica with basil and other salad leaves. | contaminated salad leaves have emerged as important vehicles for the transmission of enteric pathogens to humans. a recent outbreak of salmonella enterica serovar senftenberg (s. senftenberg) in the united kingdom has been traced to the consumption of contaminated basil. using the outbreak strain of s. senftenberg, we found that it binds to basil, lettuce, rocket and spinach leaves showing a pattern of diffuse adhesion. flagella were seen linking s. senftenberg to the leaf epidermis, and the del ... | 2009 | 18830276 |