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1.
Ferrer E Alegría A Farré R Clemente G Calvo C 《Journal of agricultural and food chemistry》2005,53(12):4911-4917
Free and total fluorescent compounds, browning index, and color formation were measured in milk-based powdered infant formulas (IF) during 2 years of storage at 20 and 37 degrees C. The excitation spectra from 415 nm emission show three peaks (ex lambda1 = 270 nm, lambda2 = 325/315 nm, lambda3 = 350 nm) and from 347 nm excitation two emission peaks (415 and 520 nm), and no wavelength shifts were observed. Temperature and time of storage exert in general no significant effect on the development of fluorescence emission intensity and browning index. However, an important increase in pentodilysine was recorded-probably because of the iron and ascorbic acid contents of the samples-as well as in browning index in adapted IF. In both IF a color increase (deltaE) throughout storage was observed, this increase being greater in samples stored at 37 degrees C than in those stored at 20 degrees C. The increase in color with time fitted a linear regression model. Color appeared to be an indicator of sufficient sensitivity to measure the effect of temperature or storage time. 相似文献
2.
Perales S Barberá R Lagarda MJ Farré R 《Journal of agricultural and food chemistry》2005,53(9):3721-3726
An adequate calcium intake during the first years of life is needed for normal growth and development and to prevent rickets. The bioavailability of calcium from infant foods (milk-based formulas and fruit juices containing milk and cereals, FMC), the dietary sources of calcium in these stages of life, has been estimated on the basis of simulated gastrointestinal digestion and calcium solubility and dialyzability values and on the efficiency of transport and uptake by Caco-2 cells. The ranking of samples according to calcium bioavailability depends on the use of solubility or dialyzability as criterion. On the basis of the former, the highest value corresponded to adapted formulas and the lowest to fruit juices. However, when using percentage dialysis, the highest value corresponded to fruit juices and the lowest to follow-up formulas. The highest percentages of transport efficiency and uptake by Caco-2 cells corresponded to calcium from the analyzed fruit juices, followed by toddler, follow-up, and adapted formulas. 相似文献
3.
García-Llatas G Cercaci L Rodriguez-Estrada MT Lagarda MJ Farré R Lercker G 《Journal of agricultural and food chemistry》2008,56(2):469-475
The effect of storage on sterol oxidation of ready-to-eat infant foods was evaluated. Two different liquid infant foods (honey or fruits flavors), prepared with milk and cereals, were stored for 0, 2, 4, 7 and 9 months at 25 degrees C. Sterol oxidation products (SOP) were isolated by cold saponification, purified by silica solid-phase extraction, and analyzed by gas chromatography (GC) and GC-mass spectrometry. beta-Sitosterol was the most representative sterol, followed by cholesterol and campesterol. No significant differences in the total and single SOP content (0.8-1 mg/kg of product) were observed with respect to storage time and type of sample; the main SOP found was 7-ketositosterol (<0.2 mg/kg of product). The extent of stigmasterol oxidation (2.9%) was higher than that of cholesterol (1.9%) and beta-sitosterol (1.4%). The type and quality of raw materials, as well as the processing conditions, seem to greatly influence SOP formation and accumulation in infant foods. 相似文献
4.
DeBusk BC Slattery M Ki JS Lee JS Aparicio-Fabre R Schlenk D 《Fish physiology and biochemistry》2008,34(4):483-492
Cytochrome P450 (CYP) has been shown to confer resistance in numerous terrestrial insects that consume potentially toxic secondary
metabolites in plants, but fewer studies have examined the role of critical biotransformation enzymes in allowing marine organisms
to consume chemically defended foods. This study examined the expression of CYP1A and CYP2N mRNAs in several butterflyfish
species, which can feed on numerous chemically defended soft and hard corals. In addition, the effect of an extract from a
soft coral (Sinnularia maxima) on expression of hepatic CYP1A and CYP2 mRNAs was also examined. Fish were fed extracts on days 1, 3 and 5, and expression
was examined on day 5. Phylogenetic analyses of the CYP1A cDNA from 12 species of butterflyfish (DNA, amino acid) indicate
well-separated groupings according to their feeding strategies. The non-coralline feeding Chaetodon xanthurus exhibited a 7-fold higher basal expression of CYP2N8 relative to the other species studied. Although induction of CYP2N7
expression was observed in C. punctatofasciatus, CYP1A and CYP2N was largely unaffected or diminished by extract treatment in the other species of butterflyfish. These results
indicated groupings of feeding strategy with CYP1A phylogeny in Chaetodon, but generally unaltered expression of CYP1A and CYP2N following dietary treatment with an extract from a chemically defended
soft coral suggesting an inconclusive role of these isoforms in the detoxification of chemicals in these extracts. 相似文献
5.
Perales S Barberá R Lagarda MJ Farré R 《Journal of agricultural and food chemistry》2006,54(13):4901-4906
Calcium solubility, dialysability, and transport and uptake (retention + transport) by Caco-2 cells as indicators of calcium bioavailability have been estimated in the in vitro gastrointestinal digests of milk and calcium fortified milk. A significant linear correlation (p < 0.05) was obtained between calcium uptake and the amount of soluble calcium added to the cells, and also between percentage calcium uptake and the calcium measured in the analyzed samples. The solubility, dialysis, transport, and uptake values are higher (p < 0.05) for calcium fortified milks than for nonfortified milks; that is, calcium fortification increases not only calcium content but also its bioavailability. An inhibitory effect of calcium from fortified milks upon iron absorption was found. The observed effect of calcium from fortified milks upon zinc bioavailability depends on the in vitro method used, zinc solubility and dialysis decrease in calcium fortified milks, and percentage zinc uptake remains unchanged. 相似文献
6.
Laparra JM Vélez D Barberá R Farré R Montoro R 《Journal of agricultural and food chemistry》2005,53(22):8829-8833
Arsenic is present in rice grain mainly as inorganic arsenic. Little is known about the effect of cooking on inorganic arsenic content in rice and its bioavailability. This study evaluated total arsenic and inorganic arsenic in rice cooked with arsenic-contaminated water, the bioaccessibility of As(III) and As(V) after simulated gastrointestinal digestion, and the extent of arsenic retention and transport by Caco-2 cells used as a model of intestinal epithelia. After cooking, inorganic arsenic contents increase significantly. After simulated gastrointestinal digestion, the bioaccessibility of inorganic arsenic reached 63-99%; As(V) was the main species found. In Caco-2 cells, arsenic retention, transport, and total uptake (retention + transport) varied between 0.6 and 6.4, 3.3 and 11.4, and 3.9 and 17.8%, respectively. These results show that in arsenic endemic areas with subsistence rice diets, the contribution of inorganic arsenic from cooked rice should be considered in assessments of arsenic health risk. 相似文献
7.
Almela C Laparra JM Vélez D Barberá R Farré R Montoro R 《Journal of agricultural and food chemistry》2005,53(18):7344-7351
The aim of this study was to examine arsenic species contents in raw and cooked edible seaweed and the bioaccessibility (maximum soluble concentration in gastrointestinal medium) of arsenosugars (glycerol ribose, phosphate ribose, sulfonate ribose, and sulfate ribose). For the analysis, a new chromatographic separation was developed in anion exchange, coupled with thermooxidation-hydride generation-atomic fluorescence spectrometry. An in vitro digestion (pepsin, pH 2; pancreatin-bile extract, pH 7) was applied to estimate arsenosugar bioaccessibility. Cooking of Undaria pinnatifida and Porphyra sp. did not alter the arsenic species present in the methanol-water extract, but it produced a substantial increase (2 and 5 times) in the As(V) extracted from Hizikia fusiforme. In all of the seaweeds analyzed, arsenosugar bioaccessibility was high (>80%) and did not vary as a result of cooking. Arsenosugar degradation as a result of in vitro digestion was not observed. 相似文献
8.
Victor M Rodriguez Pablo Velasco Rosaura Abilleira Elena Cartea 《Pest management science》2023,79(2):803-810
BACKGROUND
Plants defend themselves from insect feeding by activating specific metabolic pathways. We performed a metabolomic analysis to compare the metabolome reorganization that occurs in the leaves of two genotypes of cabbage (one partially resistant and one susceptible) when attacked by Mamestra brassicae caterpillars.RESULTS
The comparison of the metabolomic reorganization of both genotypes allowed us to identify 43 metabolites that are specifically associated with the insect feeding response in the resistant genotype. Of these, 19% are lipids or lipid-related compounds, most of which are modified fatty acids. These include glycosylated, glycerol-binding and oxidized fatty acids, the majority being associated with the oxylipin pathway. Some of the identified lipids are unlikely to be produced by plants and may be the result of biochemical reactions in the caterpillar oral secretions. A further 16% are phenylpropanoids. Interestingly, some phenylpropanoids were not present in the susceptible genotype, making them possible candidates for specific resistance-related compounds.CONCLUSION
Our results suggest that glucosinolates do not have a clear role in the resistance to M. brassicae feeding on cabbage. Using an untargeted metabolomics approach, we associated the regulation of metabolic pathways related to lipid signalling and phenylpropanoid compounds with the resistance to this pest. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献9.
10.
Alma?Tinoco Alejandro?CasasEmail author Rosaura?Luna Ken?Oyama 《Genetic Resources and Crop Evolution》2005,52(5):525-538
Escontria chiotilla is a columnar cactus that grows in the arid and semiarid lands of Central Mexico and produces edible fruit with economic.
In the wild, this plant species is distributed as part of thorn-scrub and tropical deciduous forests, but in the Tehuacán
Valley also occurs in silvicultural managed in situ populations, in which people practise artificial selection enhancing phenotypes with larger fruits. The population genetics
of wild and managed populations was studied to analyse the effects of management on genetic structure of E. chiotilla. A total of 150 individuals from six populations were studied, analysing 13 loci for eight enzymes by starch gel electrophoresis.
The genetic variation in wild populations was significantly higher than in managed populations (Ho = 0.079, He = 0.134, HT = 0.370, and Ho = 0.052, He = 0.110, HT = 0.298, respectively), indicating that silvicultural management has caused a reduction of the genetic variation in populations.
Most of the genetic variation in both wild and managed populations occurs within populations (DST = 0.027 in the wild and 0.018 in managed populations). The genetic distance coefficients were slightly different for silvicultural
managed populations than in wild ones, illustrating an incipient effect of management on the genetic structure of populations.
However, values of NmGST = 3.845 and NmFST = 3.848 indicate that a high gene flow counteracts the effects of human selection on the differentiation of populations. 相似文献