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101.
Young JF Duthie SJ Milne L Christensen LP Duthie GG Bestwick CS 《Journal of agricultural and food chemistry》2007,55(3):618-623
The polyacetylene falcarinol, isolated from carrots, has been shown to be protective against chemically induced colon cancer development in rats, but the mechanisms are not fully understood. In this study CaCo-2 cells were exposed to falcarinol (0.5-100 microM) and the effects on proliferation, DNA damage, and apoptosis investigated. Low-dose falcarinol exposure (0.5-10 microM) decreased expression of the apoptosis indicator caspase-3 concomitantly with decreased basal DNA strand breakage. Cell proliferation was increased (1-10 microM), whereas cellular attachment was unaffected by <10 microM falcarinol. At concentrations above 20 microM falcarinol, proliferation of CaCo-2 cells decreased and the number of cells expressing active caspase-3 increased simultaneously with increased cell detachment. Furthermore, DNA single-strand breakage was significantly increased at concentrations above 10 microM falcarinol. Thus, the effects of falcarinol on CaCo-2 cells appear to be biphasic, inducing pro-proliferative and apoptotic characteristics at low and high concentrations of falcarinol, respectively. 相似文献
102.
Xu T Shao XL Li QX Keum YS Jing HY Sheng W Li J 《Journal of agricultural and food chemistry》2007,55(10):3764-3770
A competitive enzyme-linked immunosorbent assay (ELISA) for pentachloronitrobenzene (PCNB), a fungicide and chemical intermediate, was developed using a polyclonal antiserum produced against a hapten-protein conjugate of pentachlorophenoxypropionic acid-bovine serum albumin (BSA). An indirect competitive ELISA of PCNB showed an IC50 of 37 ng/mL and a limit of detection (LOD) of 7 ng/mL. The ELISA can tolerate up to 10% (v/v) methanol, 5% (v/v) acetonitrile, or 5% (v/v) acetone without significant fluctuation of Amax and IC50. The assay sensitivity showed little change in a range of pH from 6 to 8 and concentrations of 0.05-0.2 M NaCl in the assay buffer. Very low cross-reactivities were observed for some structurally related compounds except for hexachlorobenzene (12%). The average recoveries of PCNB from fortified well water, river water, and soil samples were in ranges of 88-94, 80-91, and 70-81%, respectively. The correlations between the gas chromatographic and ELISA results were excellent (r 2 >or= 0.97, slopes from 0.86 to 1.10) for those fortified samples. The ELISA is a good alternative tool for monitoring PCNB residues in environmental samples. 相似文献
103.
The acaricidal activity of materials derived from rhizome of Atractylodes ovata (Atractylodes macrocephala) toward adult Dermatophagoides farinae and Dermatophagoides pteronyssinus was examined using fabric-circle residual contact and vapor-phase toxicity bioassays. Results were compared with those of the currently used acaricides: benzyl benzoate, dibutyl phthalate, and N,N-diethyl-m-toluamide (Deet). The active principles of A. ovata rhizome were identified as the sesquiterpenoids, atractylenolide III (1) and atractylon (2), by spectroscopic analysis. In fabric-circle residual contact bioassays with adult D. farinae, atractylenolide III (LD50, 103.3 mg/m2) and atractylon (136.2 mg/m2) were five and four times more toxic than Deet and 1.7- and 1.3-fold more active than dibutyl phthalate, respectively, based on 24 h LD50 values. These compounds were less toxic than benzyl benzoate (LD50, 45.8 mg/m2). Against adult D. pteronyssinus, atractylenolide III (LD50, 73.8 mg/m2) and atractylon (72.1 mg/m2) were eight times more active than Deet and 2.5-fold more toxic than dibutyl phthalate. These compounds were slightly less effective than benzyl benzoate (LD50, 46.0 mg/m2). In vapor-phase toxicity tests with both mite species, atractylenolide III and atractylon were effective in closed but not in open containers. These results indicate that the effect of these sesquiterpenoids was largely a result of action in the vapor phase. Naturally occurring atractylenolide III and atractylon merit further study as potential house dust mite control agents or leads because of their great activity as a fumigant. 相似文献
104.
Oruna-Concha MJ Methven L Blumenthal H Young C Mottram DS 《Journal of agricultural and food chemistry》2007,55(14):5776-5780
A difference in taste characteristics between the outer flesh and the inner pulp of tomatoes has been observed; in particular the pulp, which contains the seeds, had more umami taste. Analysis of the free amino acids and 5'-ribonucleotides in the different parts of 13 varieties of tomatoes showed that in all cases the pulp contained higher levels of glutamic acid, 5'-adenosine monophosphate (AMP), 5'-guanosine monophosphate, 5'-uridine monophosphate, and 5'-cytidine monophosphate. The mean concentration of glutamic acid in the flesh was 1.26 g/kg and that in the pulp 4.56 g/kg but in some varieties the difference between pulp and flesh was more than 6-fold. For AMP, the mean concentration in the flesh was 80 mg/kg and that in the pulp was 295 mg/kg with one variety showing an 11-fold difference between pulp and flesh. These differences in concentration of these compounds, which are known to possess umami characteristics, provide an explanation for the perceived difference in umami taste between the flesh and pulp of tomatoes. 相似文献
105.
Poulsen KA Young JF Theil P Kolko M Oksbjerg N Lambert IH 《Journal of agricultural and food chemistry》2007,55(5):1970-1976
The role of phospholipase A2 in the induction of drip loss from pig muscle has been investigated. In samples from porcine M. longissimus dorsi, total PLA2 activity as well as mRNA and protein levels of the group VIA iPLA2 (iPLA2-VIA) increased during the initial 4 h post-mortem period. Morphological studies of porcine muscle showed that at 4 h post-mortem, gaps had formed between muscle fibers and that the sarcolemma membrane borders appeared blurred. At the same time iPLA2-VIA protein levels were increased inside muscle fibers and at the sarcolemma. iPLA2-VIA mRNA abundance in samples from different breeds of pigs with variations in drip loss revealed no clear correlation between drip loss level and iPLA2-VIA expression. Together, these data indicate that during the post-mortem period, iPLA2-VIA expression and activity is increased at the muscle fiber membranes. PLA2 activity may affect membrane permeability and consequently the progression of drip formation in porcine muscle. 相似文献
106.
Abdel-Aal el-SM Young JC Rabalski I Hucl P Fregeau-Reid J 《Journal of agricultural and food chemistry》2007,55(3):787-794
Selected primitive and modern wheat species were evaluated on the basis of their carotenoid composition and effects of the genotype and environment on lutein using spectrometry and liquid chromatography. Carotenoids in the wheat extracts were identified and confirmed on the basis of their UV/vis and mass spectra compared with those of authentic standards. The protonated molecule (M + 1)+ at m/z 569 was the predominant ion for zeaxanthin compared to the fragment ion at m/z 551 for lutein. A similar carotenoid profile was obtained for the wheat species investigated, but significant differences were observed in the concentration of carotenoids. Einkorn (Triticum monococcum) exhibited the highest level of all-trans-lutein, averaging 7.41 microg/g with small amounts of all-trans-zeaxanthin, cis-lutein isomers, and beta-carotene. Durum, Kamut, and Khorasan (Triticum turgidum) had intermediate levels of lutein (5.41-5.77 microg/g), while common bread or pastry wheat (Triticum aestivum) had the lowest content (2.01-2.11 microg/g). Lutein in einkorn appeared to be influenced significantly by environmental growing conditions. 相似文献
107.
Abdel-Farid IB Kim HK Choi YH Verpoorte R 《Journal of agricultural and food chemistry》2007,55(19):7936-7943
The Brassica has been intensively studied due to the nutritional and beneficial effects. However, many species, varieties, and cultivars of this genus and the resulting large metabolic variation have been obstacles for systematic research of the plant. In order to overcome the problems posed by the biological variation, the metabolomic analysis of various cultivars of Brassica rapa was performed by NMR spectroscopy combined with multivariate data analysis. Discriminating metabolites in different cultivars and development stages were elucidated by diverse 2D-NMR techniques after sorting out different significant signals using (1)H NMR measurements and principal component analysis. Among the elucidated metabolites, several organic and amino acids, carbohydrates, adenine, indole acetic acid (IAA), phenylpropanoids, flavonoids, and glucosinolates were found to be the metabolites contributing to the differentiation between cultivars and age of Brassica rapa. On the basis of these results, the distribution of plant metabolites among different cultivars and development stages of B. rapa is discussed. 相似文献
108.
Kim HY Kang KS Yamabe N Nagai R Yokozawa T 《Journal of agricultural and food chemistry》2007,55(21):8491-8497
We investigated the effects of American ginseng (AG) and heat-processed American ginseng (H-AG) on diabetic renal damage using streptozotocin (STZ)-induced diabetic rats in this study. The diabetic rats showed a loss of body weight gain, and increases in kidney weight, food intake, water intake, and urine volume, whereas the oral administration of H-AG at a dose of 100 mg/kg of body weight per day for 20 days attenuated these diabetes-induced physiological abnormalities. Among the renal function parameters, the elevated urinary protein levels in diabetic control rats were significantly decreased by the AG or H-AG administrations, and the decreased creatinine clearance level was significantly increased in H-AG-administered rats. In addition, the markedly high serum levels of glucose and glycosylated protein in diabetic control rats were significantly decreased by the administration of H-AG, implying that H-AG might prevent the pathogenesis of diabetic complications caused by impaired glucose metabolism and glycosylation of serum proteins. Although no significant ameliorations were shown in overexpressed protein expressions related to diabetic oxidative stress by the AG or H-AG administrations, the accumulation of N (epsilon)-(carboxymethyl)lysine and receptors for advanced glycation endproduct (AGE) expressions were significantly reduced by the administration of H-AG. On the basis of these results, we found that AG and H-AG inhibit AGE accumulation in diabetic rat kidney by their hypoglycemic and renal function ameliorating effects, and this effect was stronger in the H-AG-administered group than in the AG-administered group. These findings indicate that H-AG may have beneficial effect on pathological conditions associated with diabetic nephropathy. 相似文献
109.
Unno T Kim SJ Kanaly RA Ahn JH Kang SI Hur HG 《Journal of agricultural and food chemistry》2007,55(21):8556-8561
Newly isolated soil bacterium strain Jin1 was able to grow on both eugenol and isoeugenol each as sole source of carbon and energy. Based on bacterial 16S rDNA analysis, Jin1 belongs to Pseudomonas nitroreducens with a similarity of 98.92% (14/1297). P. nitroreducens Jin1 was found to biotransform eugenol and isoeugenol to vanillin by different pathways. Eugenol was biotransformed to vanillin through coniferyl alcohol and ferulic acid similarly to the pathway shown previously by Pseudomonassp. HR199 and vanillin produced from eugenol was rapidly metabolized to vanillic acid. Contrastively, Pseudomonas nitroreducens Jin1 did not appear to produce metabolic intermediates during the biotransformation of isoeugenol to vanillin which was finally biotransformed to vanillic acid with much slower rate. These results indicate that there seems to be different metabolic regulation systems for the biotransformation of eugenol and isoeugenol by this bacterium. Herein, we report on Pseudomonas nitroreducens Jin1, a novel bacterium that produces vanillin from eugenol and isoeugenol by two different metabolic pathways. 相似文献
110.
Thomas Rosendal Cate Dewey Robert Friendship Sarah Wootton Beth Young Zvonimir Poljak 《Canadian journal of veterinary research》2014,78(4):250-259
A study of Ontario swine farms positive for Porcine reproductive and respiratory syndrome virus (PRRSV) tested the association between genetic similarity of the virus and similarity of clinical signs reported by the herd owner. Herds were included if a positive result of polymerase chain reaction for PRRSV at the Animal Health Laboratory at the University of Guelph, Guelph, Ontario, was found between September 2004 and August 2007. Nucleotide-sequence similarity and clinical similarity, as determined from a telephone survey, were calculated for all pairs of herds. The Mantel test indicated that clinical similarity and sequence similarity were weakly correlated for most clinical signs. The generalized additive model indicated that virus homology with 2 vaccine viruses affected the association between sequence similarity and clinical similarity. When the data for herds with vaccine-like virus were removed from the dataset there was a significant association between virus similarity and similarity of the reported presence of abortion, stillbirth, preweaning mortality, and sow/boar mortality. Ownership similarity was also found to be associated with virus similarity and with similarity of the reported presence of sows being off-feed, nursery respiratory disease, nursery mortality, finisher respiratory disease, and finisher mortality. These results indicate that clinical signs of PRRS are associated with PRRSV genotype and that herd ownership is associated with both of these. 相似文献