References of "Phuong, Nguyen Thanh"
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See detailDevelopment of an analytical method to detect metabolites of nitrofurans. Application to the study of furazolidone elimination in Vietnamese black tiger shrimp (Penaeus monodon)
Douny, Caroline ULg; Widart, Joëlle ULg; De Pauw, Edwin ULg et al

in Aquaculture (2013), 376-379

Nitrofurans, banned antibiotics in European Union (EU), have often been found in imported aquaculture products in the past and are still found nowadays according to the Rapid Alert System for Feed and ... [more ▼]

Nitrofurans, banned antibiotics in European Union (EU), have often been found in imported aquaculture products in the past and are still found nowadays according to the Rapid Alert System for Feed and Food (RASFF) of the European Commission. A quantitative method based on liquid chromatography coupled to isotopic dilution tandem mass spectrometry (LC–IDMS/MS) was developed for the determination of the residues of four nitrofuran antibiotic residues in shrimps. The experimental protocol consisted of an acid-catalysed release of protein-bound metabolites, followed by derivatisation with 2-nitrobenzaldehyde (NBA). Then, a double liquid–liquid extraction with ethyl acetate was performed before LC–IDMS/MS analysis by positive electrospray ionisation (ES+) with multiple reaction monitoring (MRM) of two transitions per compound. An “in-house” validation of the method for shrimp analysis was conducted according to the EU criteria for the analysis of veterinary drug residues in foods. The decision limits (CCalpha) were 0.08–0.36 µg kg -1 and the detection capabilities (CCbeta) were 0.12–0.61 µg kg-1, which are both below the minimum required performance limit (MRPL) set at 1 µg kg -1 by the EU. The developed method was applied to evaluate the elimination of furazolidone residues in shrimp muscles after a contamination experiment. After 28 days of decontamination, a concentration of 115 µg kg-1 of furazolidone metabolite 3-amino-2-oxazolidinone (AOZ) was still measured in shrimp muscle. [less ▲]

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See detailExpression characteristics of potential biomarker genes in Tra catfish, Pangasianodon hypophthalmus, exposed to trichlorfon
Sinha, Amit Kumar; Vanparys, Caroline; De Boeck et al

in Comparative Biochemistry and Physiology. Part D, Genomics & Proteomics (2010), 5(3), 207-216

Trichlorfon (TRC) is the most common organophosphorous insecticide used in aquaculture practices in Southeast Asian countries. Indiscriminate use of TRC can either damage or alter the enzymatic and ... [more ▼]

Trichlorfon (TRC) is the most common organophosphorous insecticide used in aquaculture practices in Southeast Asian countries. Indiscriminate use of TRC can either damage or alter the enzymatic and hormonal activities in the living organisms. In this present study, therefore, toxicogenomic analyses using real time PCR was used to characterize expression levels of various genes in Pangasianodon hypophthalmus after exposure to three concentrations, the 96 h 1/100LC50 (0.01 mg/L), the 96 h 1⁄10LC50 (0.1 mg/L) and the 96 h 1⁄2LC50 (0.5 mg/L) of TRC for 6 h, 24 h, 96 h, 7 days, 14 days, 28 days and 56 days respectively. The expression kinetics of stress and other cellular toxicity representative genes such as heat shock protein70 (HSP70), growth hormone, acetylcholinesterase (AChE), trypsinogen, cytochrome P4501B (CYP1B) and cytochrome oxidase subunit 1 (COI) were investigated in liver and gills. TRC at a level of 0.1 mg/L and 0.5 mg/L induced a time and dose-dependent increase in the expression of the HSP70, COI and CYPIB while the transcript level of AChE, growth hormone and trypsinogen were significantly down-regulated. These results could permit to develop a ‘molecular biomarker system’ which can be applied as a first-tier method of identifying contaminant exposure before effects at population level occur. [less ▲]

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See detailAcetylcholinesterase activity as a biomarker of exposure to antibiotics and pesticides in the black tiger shrimp (Penaeus monodon).
Tu, Huynh Thi; Silvestre, Frederic; Scippo, Marie-Louise ULg et al

in Ecotoxicology & Environmental Safety (2009), 72(5), 1463-70

This study aimed to assess the potentiality to use cholinesterase activity (ChE) in black tiger shrimp (Penaeus monodon) as a biomarker of exposure to 2 antibiotics (enrofloxacin, furazolidone) and 2 ... [more ▼]

This study aimed to assess the potentiality to use cholinesterase activity (ChE) in black tiger shrimp (Penaeus monodon) as a biomarker of exposure to 2 antibiotics (enrofloxacin, furazolidone) and 2 pesticides (endosulfan, deltamethrin), commonly used in Vietnamese farms. ChE from muscle and gills was first characterised using three different substrates and specific inhibitors. Results showed that both tissues possess only one ChE which displays the typical properties of an acetylcholinesterase (AChE). In a second part, shrimp (average weight of 8.8-10 g) were fed with medicated-feed containing 4g enrofloxacin (quinolone) or furazolidone (nitrofuran)/kg for 7 days, or exposed to 3 actual concentrations of endosulfan (0, 0.009, 0.09, 0.9 microg/L) or deltamethrin (0, 0.0007, 0.007, 0.07 microg/L) for 4 days. After treatment, animals were decontaminated during 7 days. We observed that AChE activity in muscle was not significantly affected in shrimp fed with enrofloxacin or furazolidone, while it significantly decreased (up to 28%) in gills of shrimp fed with furazolidone. Following endosulfan and deltamethrin exposure, no significant changes in AChE activity were observed in gills. However, a significant decrease occurred in muscle after 4 days exposure (inhibition of 30% and 49% at 0.9 microg/L endosulfan and 0.07 microg/L deltamethrin, respectively). While muscle AChE activity should be assessed to point out endosulfan or deltamethrin exposure, gill AChE activity impairment could indicate an exposure to furazolidone. The present study underlines the benefits to use AChE as a biomarker of chemotherapeutics as part of an integrated aquaculture management to reach industry sustainability. [less ▲]

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