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Preharvest contamination of field crops may have many sources, including feces, soil, and irrigation water. In March 2000, a sewage spill released unchlorinated tertiary-treated effluent into a creek used to irrigate commercial produce. A field of young cabbage transplants was irrigated with creek water as the contaminated water flowed past this land. Cabbage samples were taken from plots within this field, and Escherichia coli was isolated from the roots of these plants but not from the edible portion of the cabbage. No E. coli was isolated from water samples or from control samples taken from a nearby cabbage field watered with chlorinated municipal water. The cabbage field under study had not been fertilized with manure for at least 2 years prior to the contamination incident. Six different E. coli serotypes were identified, although none of them proved to be pathogenic. These serotypes were separated into five groups by a RiboPrinter; the resulting groups correlated well with the serotypes and the locations in the field from which these strains were isolated. We previously found that certain nonpathogenic E. coli strains displayed lower levels of adherence to lettuce seedling roots in a hydroponic adherence assay. The E. coli field strains displayed variable patterns of adherence to lettuce seedlings: strain MW421 showed significantly lower root and shoot adherence levels than did the other field strains, while strains MW423 and MW425 showed significantly higher root and shoot adherence levels. These data suggest that water quality is of paramount importance for the food safety of growing crops. 相似文献
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Experimental breads were made with 2, 4, 6, 8, 10, and 12% torula yeast flour (TYF). Taste panels found that bread fortified with 8% TYF was acceptable. Eight percent TYF raised protein content from 12.42% for all wheat flour bread to 14.22% for supplemented bread. Amino acid analyses indicated a marked increase in amino acid content especially lysine. The protein efficiency ratio (PER) for rats on all-wheat-flour bread was 1.3 1; replacing 8% of the wheat flour with TYF raised PER of supplemented bread to 2.28. Total carcass nitrogen retained by animals fed a diet containing supplemented bread was higher than that retained by rats whose protein was obtained from unsupplemented bread. 相似文献
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Tanya K Gachovska Marian V Simpson Michael O Ngadi GSV Raghavan 《Journal of the science of food and agriculture》2009,89(14):2372-2376
BACKGROUND: In this study the effects of pulsed electric field (PEF) pretreatment were evaluated during drying and rehydration of carrots. Carrots pretreated with an electric field intensity of 1 kV cm?1 (capacitance 0.5 µF, 20 pulses) or 1.5 kV cm?1 (capacitance 1 µF, 20 pulses) as well as blanched (100 °C, 3 min) carrots were used for the study. Following pretreatment, samples were oven dried at 70 °C and then rehydrated in distilled water (1:30 w/v) at room temperature (24 ± 1 °C). RESULTS: PEF pretreatment increased the drying rate of carrots. However, the rehydration rate of PEF‐pretreated carrots was lower than that of blanched carrots. There were no colour differences between PEF‐pretreated and blanched carrots before drying and after rehydration. In terms of texture, PEF‐pretreated carrots were firmer than blanched carrots. PEF pretreatment reduced the activity of peroxidase by 30–50%, while blanching completely inactivated the enzyme (>95%). CONCLUSIONS: Overall, the results suggest that PEF could be an effective pretreatment during drying and rehydration of carrots. Copyright © 2009 Society of Chemical Industry 相似文献
16.
Millets are generally dehulled and subjected to a hydrothermal treatment before consumption, thus the hulls can be used as a potential source of antioxidants. Several millet grains, namely kodo, finger (Ravi), finger (local), proso, foxtail, little and pearl millet were studied. Antioxidant activities of phenolic extracts obtained from whole grains, as well as their corresponding dehulled and cooked grains and hulls were studied for their total phenolic content (TPC), radical scavenging capacity, and antioxidant activity in a β-carotene/linoleate emulsion. The phenolics present in whole grains were identified and quantified using HPLC and HPLC/MS and results were expressed as total for each of the phenolic groups. The TPC ranged from 2 to 112 μmol ferulic acid equivalents/g defatted meal. All varieties exhibited effective inhibition of 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl, peroxyl and superoxide radicals. Dehulling and cooking affected the TPC and radical scavenging and antioxidant activities of the grains, depending on the variety. In general, the antioxidant activity of phenolic extracts was in the order of hull > whole grain > dehulled grain > cooked dehulled grain With the exception of the two finger millet varieties, hulls of other millet grains had high TPC, thus demonstrating their superior antioxidant activity. Hydroxybenzoic acids, hydroxycinnamic acids and flavonoids in whole grains were identified as contributors to the observed effects. Therefore, dehulling of grain and hydrothermal treatments affect the phenolic content and antioxidant potential of millet grains. 相似文献
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Zuzana Mace
kov Agta Kubí
kov Juan Bautista De Sanctis Marian Hajdúch 《International journal of molecular sciences》2022,23(3)
Diamond-Blackfan anaemia (DBA) is a red blood cell aplasia that in the majority of cases is associated with ribosomal protein (RP) aberrations. However, the mechanism by which this disorder leads to such a specific phenotype remains unclear. Even more elusive is the reason why non-specific agents such as glucocorticosteroids (GCs), also known as glucocorticoids, are an effective therapy for DBA. In this review, we (1) explore why GCs are successful in DBA treatment, (2) discuss the effect of GCs on erythropoiesis, and (3) summarise the GC impact on crucial pathways deregulated in DBA. Furthermore, we show that GCs do not regulate DBA erythropoiesis via a single mechanism but more likely via several interdependent pathways. 相似文献
20.
Vladimír Matlach Daniel Dostl Marian Novotný 《International journal of molecular sciences》2022,23(3)
This article examines the presence of the empirical tendency known as the Menzerath–Altmann Law (MAL) on protein secondary structures. MAL is related to optimization principles observed in natural languages and in genetic information on chromosomes or protein domains. The presence of MAL is examined on a non-redundant dataset of 4728 proteins by verifying significant, negative correlations and testing classical and newly proposed formulas by fitting the observed trend. We conclude that the lengths of secondary structures are specifically dependent on their number inside the protein sequence, while possibly reflecting the formula proposed in this paper. This behavior is observed on average but is individually avoidable and possibly driven by a latent cost function. The data suggest that MAL could provide a useful guiding principle in protein design. 相似文献