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Fluoroquinolone pollution of food, water and soil, and bacterial resistance Texto completo
2015
Rusu, Aura | Hancu, Gabriel | Uivaroşi, Valentina
Fluoroquinolones are a valuable synthetic antibacterial class widely used in the treatment of infectious diseases both in humans and animals. Until recently, it has been thought that bacterial resistance to fluoroquinolones develops very slowly. Nowadays, there are multiple studies that reveal the alarming occurrence of bacterial resistance and there is a high risk of becoming therapeutically useless. The emergence of this phenomenon comes from injudicious usage in therapy, the presence of residues and their metabolites in food of animal origin and also in sewage, compost and domestic waste, which end up in soil and water sources. In the present paper, we reviewed important issues regarding fluoroquinolones impact on the environment in connection with the development of bacterial resistance: (1) the presence of fluoroquinolones as pollutants in soil, surface waters, and food. Fluoroquinolones are persistent with high specificity to interact with soil compared to other antibiotics. Pollution of water sources raises concerns regarding the effects of small concentrations (ng L⁻¹) on human health and also of the environment. The non-therapeutic use in animal farms conducts to food pollution; the cultivated plants could concentrate the fluoroquinolones (over 100 μg L⁻¹); (2) the increase of bacterial resistance to fluoroquinolones occurring with specific mutations in the target enzymes as well by the plasmid-mediated resistance and active efflux of the cell; (3) international regulations of the fluoroquinolone residues in food that are far to encompass all compounds; (4) fluoroquinolones residues analysis with standardized methods should provide limits of detection lower than maximum residue limit values; and (5) trends and perspectives: (a) a wider process of harmonization of regulations; (b) the fluoroquinolones restriction, necessary for low levels of bacterial resistance; (c) the soil and waste water purification methods; (d) the practice of soil planting scheme as an alternative; and (e) an environmental label in order to facilitate the selection of drugs.
Mostrar más [+] Menos [-]Degradation of Residual Herbicide Atrazine in Agri-Food and Washing Water Texto completo
2022
Hong, Junting | Boussetta, Nadia | Enderlin, Gérald | Merlier, Franck | Grimi, Nabil
Atrazine, an herbicide used to control grassy and broadleaf weed, has become an essential part of agricultural crop protection tools. It is widely sprayed on corn, sorghum and sugar cane, with the attendant problems of its residues in agri-food and washing water. If ingested into humans, this residual atrazine can cause reproductive harm, developmental toxicity and carcinogenicity. It is therefore important to find clean and economical degradation processes for atrazine. In recent years, many physical, chemical and biological methods have been proposed to remove atrazine from the aquatic environment. This review introduces the research works of atrazine degradation in aqueous solutions by method classification. These methods are then compared by their advantages, disadvantages, and different degradation pathways of atrazine. Moreover, the existing toxicological experimental data for atrazine and its metabolites are summarized. Finally, the review concludes with directions for future research and major challenges to be addressed.
Mostrar más [+] Menos [-]The effect of food or water deprivation on paracetamol pharmacokinetics in calves Texto completo
2003
Janus, K. | Grochowina, B. | Antoszek, J. | Suszycki, S. | Muszczynski, Z.
This study investigated the effect of food or water deprivation on the pharmacokinetics of paracetamol in 30 Holstein-Friesian preruminant calves (10 controls, 10 food withheld and 10 water-deprived) aged 24–25 days. Control calves were given paracetamol at 24–25 days and again at 28–29 days of age. In the food withheld and water-deprived calves paracetamol studies were performed before and after 4 days of food or water deprivation. In the control group there were no significant differences in pharmacokinetic parameters for paracetamol in 24–25 and 28–29-day-old calves. Witholding food for 4 days was associated with an increase in the mean residence time (MRT) of paracetamol (P < 0.01). When food was withheld total body clearance (ClB) of paracetamol was significantly decreased (P < 0.05). The volume of distribution (V(ss)) was not significantly altered. Similarly, water deprivation was associated with a significant increase in MRT and significant decrease in ClB of paracetamol (P < 0.01). The V(ss) was not significantly altered. Food or water deprivation also influenced the formation of major metabolites (glucuronide and sulphate) of paracetamol. It is concluded that food or water deprivation may impair the elimination drugs that undergo metabolism by UDP-glucuronyltransferase and sulphotransferase in cattle.
Mostrar más [+] Menos [-]Vasopressin and nitric oxide synthesis after three days of water or food deprivation Texto completo
2006
Mornagui, B. | Grissa, A. | Duvareille, M. | Gharib, C. | Kamoun, A. | El-Fazaa, S. | Gharbi, N.
Nitric oxide has been suggested to be involved in the regulation of fluid and nutrient homeostasis. In the present investigation, vasopressin and nitric oxide metabolite (nitrite and nitrate) levels were determined in plasma of male Wistar rats submitted to water or food deprivation for three days. Hematocrit and plasma sodium showed marked increase in dehydrated and starved rats. Potassium levels and plasma volume decreased in both treated groups. Plasma osmolality and vasopressin levels were significantly elevated in water deprived (362.8±7.1 mOsm/kg H<sub>2</sub>O, 17.3±2.7 pg/ml, respectively, p<0.001) rats, but not in food deprived (339.9±5.0, 1.34±0.28) rats, compared to the controls (326.1±4.1, 1.47±0.32). The alterations observed in plasma vasopressin levels were related to plasma osmolality rather than plasma volume. Plasma levels of nitrite and nitrate were markedly increased in both water and food deprived rats (respectively, 2.19±0.29 mg/l and 2.22±0.17 mg/l <i>versus</i>1.33±0.19 mg/l, both p<0.01). There was a significant negative correlation between plasma nitrite and nitrate concentration and plasma volume. These results suggest that both dehydration and starvation increase plasma nitric oxide, probably by activation of nitric oxide synthases. The release of nitric oxide may participate in the regulation of the alteration in blood flow, fluid and nutrient metabolism caused by water deprivation or starvation.
Mostrar más [+] Menos [-]Using a Concentrate of Phenols Obtained from Olive Vegetation Water to Preserve Chilled Food: Two Case Studies Texto completo
2016
Fasolato, Luca | Cardazzo, Barbara | Balzan, Stefania | Carraro, Lisa | Andreani, Andrea Nadia | Taticchi, Agnese | Yambo,
Phenols are plant metabolites characterised by several interesting bioactive properties such as antioxidant and bactericidal activities. In this study the application of a phenols concentrate (PC) from olive vegetation water to two different fresh products – gilt-head seabream (Sparus aurata) and chicken breast – was described. Products were treated in a bath of PC (22 g/L; chicken breast) or sprayed with two different solutions (L1:0.75 and L2:1.5 mg/mL; seabream) and then stored under refrigeration conditions. The shelf life was monitored through microbiological analyses – quality index method for seabream and a specific sensory index for raw breast. The secondary products of lipid-peroxidation of the chicken breast were determined using the thiobarbituric acid reactive substances (TBARs) test on cooked samples. Multivariate statistical techniques were adopted to investigate the impact of phenols and microbiological data were fitted by DMfit software. In seabream, the levels of PC did not highlight any significant difference on microbiological and sensory features. DMfit models suggested an effect only on H₂S producing bacteria with an increased lag phase compared to the control samples (C: 87 h vs L2: 136 h). The results on chicken breast showed that the PC bath clearly modified the growth of Pseudomonas and Enterobacteriaceae. The phenol dipping was effective in limiting lipid-peroxidation (TBARs) after cooking. Treated samples disclosed an increase of shelf life of 2 days. These could be considered as preliminary findings suggesting the use of this concentrate as preservative in some fresh products.
Mostrar más [+] Menos [-]Food analysis – samples preparation and chromatographic methods in determination of selected biogenic amines, methylxanthines and water-soluble vitamins Texto completo
2012
Płonka, Joanna
The expanding demands of consumers requires food quality control to be improved all the time. Higher concentration of biogenic amines can lead to food toxicity, for example they can cause migraine headaches in people who consume products rich of serotonin or tyramine. Methylxanthines (caffeine and metabolites) can also have side effects to human comfort – high doses can lead to unrest, irritation or insomnia. Most vitamins are supplied to humans only as a part of food meals or dietary supplements. Knowledge about their concentration in food can be useful for composing various diets. In this work specification of complete sample preparation parameters for extraction of the compounds from food matrices has been reviewed. Particular attention was given to the preparation stage as well as to extraction methods that have been used. The second part of the work presents data from chromatographic methods for determination and separation of selected biogenic amines, methylxanthines and water-soluble vitamins in food. Stationary and mobile phases, detection methods as well as validation data have been reviewed. This publication is a comprehensive compendium of analytical procedures for food analyses of the previously mentioned compounds.
Mostrar más [+] Menos [-]Food-grade antioxidants for control of Aspergillus section Flavi and interrelated mycoflora of stored peanuts with different water activities Texto completo
2009
Passone, M. | Doprado, M. | Etcheverry, M.
The inhibitory effect of butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) mixture on fungal populations, Aspergillus section Flavi and aflatoxins accumulation in in-pod peanuts during storage in big bags was investigated. In-pod peanuts were previously conditioned at different water activities (0.94, 0.88, 0.84 and 0.76 aw) and treated with food-grade antioxidants. Both control and treated peanuts were stored for 6 months and sampled at monthly intervals. BHA-BHT mixture reduced the incidence of peanut fungal populations between 0.6-20.4% and between 1.2-33.1% during 1-3 and 4-5 storage months, respectively. Aspergillus section Flavi counts decreased with 36.5%, 46.3% and 77.4% in peanuts conditioned at 0.94, 0.84 and 0.76 aw levels and treated with antioxidants. At the above peanut aw conditions, the treatment applied reduced aflatoxin accumulation by 72.1%, while any effect on this metabolite production was observed at 0.88 aw. The antioxidant formulation used in this study has the potential to control aflatoxigenic populations in in-pod peanuts stored in half-permeable silos at ≤0.84 aw level.
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