108 research outputs found
Influence of acetate and CO<sub>2</sub> on the TMAO-reduction reaction by <i>Shewanella baltica</i>
In this work, the TMAO-reduction by Shewanella baltica, one of the representative spoilage organisms in modified atmosphere packaged marine fish fillets, and the effect of acetate and CO2 on this reduction were studied in vitro. The growth of S. baltica and the corresponding evolution of some compounds (acetate, lactate, pyruvate, glucose and trimethylamine (TMA)) were followed during storage at 4 degrees C in two types of broths. The first medium was a defined medium (pH = 6.8) to which lactate or pyruvate was added as hydrogen donor. Pyruvate showed to be more efficient as H-donor for S. baltica than lactate, as growth was much faster when equimolar amounts of pyruvate instead of lactate were present. Although the growth of S. baltica, when pyruvate is used as H-donor and no acetate is added, was not much inhibited by the CO2-atmosphere, CO2 had a pronounced effect on the studied reactions as it partly inhibited the reduction of pyruvate to acetate. The effect of acetate on this reaction was, on the other hand, not significant. To simulate the reactions occurring in situ, a buffered fish extract (pH = 6.8) was used. In spite of the neutral pH, the growth of S. baltica in this medium was highly inhibited by relatively small concentrations of acetate (S. baltica, from which the pathway seems to be less energy efficient. This can be deduced from the exceptional growth inhibition of S. baltica by small amounts of acetate. However, when practical storage times for fish (e.g. 6 days at 4 degrees C after packaging) are considered, growth and TMAO-reduction by S. baltica was completely inhibited during this period by 0.25% of acetate
Analyse du risque posé en santé animale par la présence de l'hydroxyméthylfurfural dans les sirops de nourrissement des abeilles domestiques
This paper discusses an incident that occurred in Belgium during winter 2009-2010, after which many honey bee colonies have been lost. Later analyses showed that these colonies had been fed during the winter with a inverted sugar syrup from sugar beet which had a high concentration of hydroxymethylfurfural (HMF). HMF concentrations ranged from 18.8 ppm to 365.6 ppm. Data from the scientific literature are quite limited, but several authors confirm the harmful effect of HMF on honey bee health. Other elements, however, may have played a role in this apparent mortality such as crystallization of syrups, resulting in unavailability of sugar for the honey bees, and thus the death of them from starvation. Pending the acquisition of new scientific knowledge on the subject, it is recommended to follow good beekeeping practices detailed in this article to minimize the formation of HMF in syrups for honey bee feeding. In addition, a draft action limit corresponding to a maximal concentration of 40 ppm of HMF is proposed in order to control the risk at the producer and distributor of syrups for honey bee feeding level
Post-harvest interventions decrease aflatoxin and fumonisin contamination in maize and subsequent dietary exposure in Tanzanian infants : a cluster randomised-controlled trial
A cluster randomised controlled trial was performed in three agro-ecological zones of Tanzania to evaluate the effectiveness of locally available post-harvest mitigation strategies in preventing and reducing aflatoxin and fumonisin contamination in maize. A total of 300 children, each from one household, were randomly selected from 30 villages (intervention: n=15). The mitigation strategies focused on hand sorting (prior to storage and use), drying maize on mat/raised platforms, proper sun drying, application of storage insecticides and de-hulling before milling. Maize sample was collected from each household at harvest (baseline) and six months after harvest. Maize intake by each child, estimated using the 24 h dietary recall technique and its body weight measured using standard procedures were taken at six months after harvest. Aflatoxins and fumonisins in the maize samples were determined using HPLC. Follow-up (six month after harvest) data were available for 261 of the 300 households (intervention: n=136). Mean concentration of aflatoxins, or fumonisins was significantly (P<0.05) lower in the intervention than in the control group: intervention effects: mu g/kg (95% confidence interval (CI)) -4.9 (-7.3,-2.5), and -405, (-647,-162), respectively. The difference corresponds to 83 and 70% for aflatoxins, and fumonisins, respectively. At the end of the intervention, aflatoxin and fumonisin estimated mean intakes were lower in the intervention than in the control group by 78 and 65%, respectively. Six months after harvest, prevalence of underweight in the intervention group was 6.7% lower (P=0.014) than in the control group. Mean weight-for-age Z-score difference between the groups was 0.57 (95% CI; 0.16,-0.98; P=0.007). Post-harvest practices are effective in preventing and reducing aflatoxin and fumonisin contamination in maize and subsequent dietary exposure to infants. The interventions may be applied in these and other communities with similar environmental conditions or agricultural practices that favour production of aflatoxin and fumonisins in food crops
Most Plastic Products Release Estrogenic Chemicals: A Potential Health Problem That Can Be Solved
Background: Chemicals having estrogenic activity (EA) reportedly cause many adverse health effects, especially at low (picomolar to nanomolar) doses in fetal and juvenile mammals
Interlaboratory exercise for the analysis of carotenoids and related compounds in dried mango fruit (Mangifera indica L.)
An interlaboratory comparison was done for the analysis of carotenoids in freeze-dried mango. The study was performed from July to September 2018. Mango fruit was freeze-dried, homogenized, and packaged under vacuum conditions in portions of 6 g (test sample). Two test samples were sent to the participating laboratories for analysis. Laboratory results were rated using Z-scores in accordance with ISO 13528 and ISO 17043. The standard deviation for proficiency assessment (also called target standard deviation) was determined using a modified Horwitz function and varied between 10% and 25%, depending on the analyte. Out of 14 laboratories from 10 different countries, 9 laboratories (64%) obtained a satisfactory performance (Z ≤ 2) for the analysis of β-carotene. While for 7 laboratories that analyzed α-carotene, (9Z)-β-carotene, β-cryptoxanthin, and zeaxanthin, 4 laboratories (57%) obtained a satisfactory performance. However, only 2 laboratories out of 7 (29%) obtained a satisfactory performance for lutein. Based on the comparability of the analytical results, this study concludes that freeze-dried mango pulp can be used as a reference material for the analysis of α and β-carotene, (9Z)-β-carotene, β-cryptoxanthin, and zeaxanthin by applying different analytical procedures for their extraction and quantification
Release of alpha-tocopherol from antioxidative low-density polyethylene film into fatty food simulant: Influence of complexation in beta-cyclodextrin
Effect of repetitive lysine–tryptophan motifs on the bactericidal activity of antimicrobial peptides
Production of Coturnix quail immunoglobulins Y (IgYs) against Vibrio parahaemolyticus and Vibrio vulnificus
This research article published by Springer Nature Switzerland AG., 2011Production of chicken immunoglobulins Y (IgYs) and their applications in prophylactic, therapeutic, detection of microbial contaminants and as a diagnostic tool has been widely studied with limited information from other avians. This study produced Coturnix quail (Coturnix coturnix japonica) egg yolk IgYs against Vibrio parahaemolyticus and Vibrio vulnificus. Formalin inactivated (FIVP, FIVV, mixed FI-VP/VV) and heat inactivated (HIVP, HIVV, mixed HI-VP/VV) Vibrio immunogens (109 CFU/mL) were intramuscularly immunized into quail through thigh muscles. Egg yolk IgY was purified by water dilution-ammonium sulfate precipitation method and the activity was determined by enzyme-linked immunosorbent assay (ELISA). Formalin inactivated immunogens induced high humoral immune response for both V. parahaemolyticus and V. vulnificus over heat inactivated immunogens. However, IgYs resulted from HIVP and FIVV immunogens, showed high specificity to V. parahaemolyticus and V. vulnificus respectively. Detection limits of the indirect ELISA using the produced IgYs were 105 CFU/mL for V. parahaemolyticus and 106 CFU/mL for V. vulnificus. The developed antibodies showed high binding affinity to their corresponding immunogens, very little cross reactivity to Staphylococcus aureus and not other bacteria strains (p<0.05), a phenomenon which was also observed in Western blot
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