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S Vassal - One of the best experts on this subject based on the ideXlab platform.

  • detection of hospital wastewater genotoxicity with the SOS Chromotest and ames fluctuation test
    Chemosphere, 2003
    Co-Authors: B Jolibois, M Guerbet, S Vassal
    Abstract:

    The genotoxic potential of Rouen University Hospital wastewater was evaluated by the SOS Chromotest (on Escherichia coli PQ37) and Ames fluctuation test on Salmonella typhimurium strains TA 98 and TA 100 without metabolic activation. The samples were taken during the hospital maximal activity period (8:00 a.m. to 6:00 p.m.) over three one-week periods of the year. The simultaneous use of SOS Chromotest and Ames fluctuation test allows us to carry out a preliminary screening of the hospital wastewater and to gain some insight by which mechanism the genotoxic compounds act. Out of a total of 18 daytime unconcentrated samples tested, 10 (55%) are positive in at least one assay. The two tests have different sensitivity. Indeed, nine genotoxic samples (50%) are detected by the Ames test, and four (22%) by the SOS Chromotest. Distribution and intensity of the genotoxic response are different at the three periods. In order to explain this phenomenon, the influence of the rain levels is discussed. This work showed that the hospital wastewater samples tested were overall genotoxic, the response intensity being inflected by the pluviometry. Efforts are now under way to try to identify one or several genotoxic compounds in order to take precautionary measures to limit their release in hospital wastewaters.

Kamel Ghedira - One of the best experts on this subject based on the ideXlab platform.

  • phytochemical antimicrobial antioxidant and antigenotoxic potentials of cyperus rotundus extracts
    South African Journal of Botany, 2011
    Co-Authors: Soumaya Kilanijaziri, Wissem Bhouri, Ines Skandrani, Leila Chekirghedira, I Limem, Kamel Ghedira
    Abstract:

    Abstract The aqueous, ethyl acetate, methanolic and Total Oligomer Flavonoids (TOF) enriched extracts, obtained from the aerial parts of Cyperus rotundus , were investigated for their contents in phenolic compounds. Antioxidative activity using the NBT/riboflavin assay system, antimicrobial activity against Gram positive and Gram negative bacterial reference strains as well as antigenotoxic activity tested with the SOS Chromotest assay were also studied. Significant antibacterial activity against reference strains; Staphylococcus aureus , Enterococcus faecalis , Salmonella enteritidis and Salmonella typhimurium , was detected in the presence of ethyl acetate and TOF enriched extracts. In addition to their antimicrobial activity, the same extracts showed a significant ability to inhibit nitroblue tetrazolium reduction by the superoxide radical in a non enzymatic O 2 .− generating system, and were also able to reduce significantly the genotoxicity induced by nifuroxazide and Aflatoxin B1. The antioxidant, antimicrobial and antigenotoxic activities exhibited by C. rotundus depend on the chemical composition of the tested extracts.

  • evaluation of antioxidant and antigenotoxic activity of two flavonoids from rhamnus alaternus l rhamnaceae kaempferol 3 o β isorhamninoside and rhamnocitrin 3 o β isorhamninoside
    Food and Chemical Toxicology, 2011
    Co-Authors: Wissem Bhouri, Kamel Ghedira, Ines Bouhlel, Mohamed Ben Sghaier, Soumaya Kilani, Mariegenevieve Dijouxfranca, Leila Chekir Ghedira
    Abstract:

    Abstract The antioxidant activity of kaempferol 3-O-β-isorhamninoside (K3O-ir) and rhamnocitrin 3-O-β-isorhamninoside (R3O-ir), isolated from the leaves of Rhamnus alaternus L., was determined by the ability of each compound to inhibit NBT photoreduction and to scavenge the free radical ABTS + . Genotoxic and antigenotoxic activities were assessed using the SOS Chromotest. At a concentration of 150 μg/assay the two compounds showed the most potent inhibitory activity against superoxide anion by respectively 80.4% and 85.6%. K3O-ir was a very potent radical scavenger with an IC 50 value of 18.75 μg/ml. Moreover, these two compounds exhibit an inhibitory activity against genotoxicity induced by nitrofurantoine and aflatoxine B1 using the SOS Chromotest bacterial assay system in the presence of Escherichia coli PQ37 strain. In this study, we have also evaluated correlation between antigenotoxic and antioxidant effects of K3O-ir and R3O-ir. The highest correlation was showed with R3O-ir ( r  = 0.999).

  • Study of genotoxic, antigenotoxic and antioxidant activities of the digallic acid isolated from Pistacia lentiscus fruits.
    Toxicology in vitro : an international journal published in association with BIBRA, 2009
    Co-Authors: Wissem Bhouri, Ines Skandrani, Safa Derbel, Jihed Boubaker, Ines Bouhlel, Mohamed Ben Sghaier, Soumaya Kilani, A Mariotte, Marie G. Dijoux-franca, Kamel Ghedira
    Abstract:

    Abstract The digallic acid obtained from the fruit Pistacia lentiscus exhibits an inhibitory activity against nitrofurantoine and B[ a ]P induced genotoxicity when tested by the SOS Chromotest bacterial assay system in the presence of Escherichia coli PQ37 strain. The antioxidant activity of the tested compound was determined by its ability to scavenge the free radical ABTS + , to inhibit the xanthine oxidase, involved in the generation of free radicals, and to inhibit the lipid peroxidation induced by H 2 O 2 in the K562 cell line. Our results revealed that digallic acid shows an important free radical scavenging activity towards the ABTS + radical (99%) and protection against lipid peroxidation (68%).

  • chemical composition antibacterial and antimutagenic activities of essential oil from tunisian cyperus rotundus
    Journal of Essential Oil Research, 2005
    Co-Authors: Soumaya Kilani, Kamel Ghedira, Afef Abdelwahed, Ribai Ben Ammar, Nawel Hayder, Imed Chraief, Mohamed Hammami, Leila Chekirghedira
    Abstract:

    Abstract Essential oil from the tubers of Cyperus rotundus, obtained by steam distillation, was analyzed by GC and GC/MS. In total, 33 compounds were identified. The oil was characterized by its high content of sesquiterpenes with cyperene (30.9%) being major. The antibacterial activity of oil from tubers of Cyperus rotundus, showed more important activity against Gram-positive bacteria specially Staphylococcus aureus than Gram-negative bacteria. The antimutagenic activity was tested by the “SOS Chromotest” and the “Ames” test. C. rotundus oil acted as an antimutagen against Afl atoxin B1 in both Salmonella strains (TA100 and TA98) and Escherichia coli strain (PQ37) and against nifuroxazide in Escherichia coli strain (PQ37), where its mutagenicity is not expressed. The highest rates of AFB1 mutagenesis inhibition tested by Ames assay, ranged from about 82.56% for TA100 strain to 85.47% for TA98 strain at the same dose of 50 μg AFB1 per plate. Whereas, the mutagenic effect of respectively nifuroxazide and ...

  • anti genotoxic and free radical scavenging activities of extracts from tunisian myrtus communis
    Mutation Research-genetic Toxicology and Environmental Mutagenesis, 2004
    Co-Authors: Nawel Hayder, Kamel Ghedira, Soumaya Kilani, Afef Abdelwahed, Ben R Ammar, Amor Mahmoud, Leila Chekirghedira
    Abstract:

    Abstract The effect of extracts from leaves of Myrtus communis on the SOS reponse induced by Aflatoxin B1 (AFB1) and Nifuroxazide was investigated in a bacterial assay system, i.e. the SOS Chromotest with Escherichia coli PQ37. Aqueous extract, the total flavonoids oligomer fraction (TOF), hexane, chloroform, ethyl acetate and methanol extracts and essential oil obtained from M. communis significantly decreased the SOS response induced by AFB1 (10 μg/assay) and Nifuroxazide (20 μg/assay). Ethyl acetate and methanol extracts showed the strongest inhibition of the induction of the SOS response by the indirectly genotoxic AFB1. The methanol and aqueous extracts exhibited the highest level of protection towards the SOS-induced response by the directly genotoxic Nifuroxazide. In addition to anti-genotoxic activity, the aqueous extract, the TOF, and the ethyl acetate and methanol extracts showed an important free-radical scavenging activity towards the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. These results suggest the future utilization of these extracts as additives in chemoprevention studies.

Marina Isidori - One of the best experts on this subject based on the ideXlab platform.

  • eco genotoxicity of six anticancer drugs using comet assay in daphnids
    Journal of Hazardous Materials, 2015
    Co-Authors: Alfredo Parrella, Margherita Lavorgna, Emma Criscuolo, Chiara Russo, Marina Isidori
    Abstract:

    Abstract The eco-genotoxicity of six anti-neoplastic drugs, 5-fluorouracil, capecitabine, cisplatin, doxorubicin, etoposide, and imatinib, belonging to five classes of anatomical therapeutic classification (ATC), was studied applying the in vivo comet assay on cells from whole organisms of Daphnia magna and Ceriodaphnia dubia . For the first time, this test was performed in C. dubia. In addition, to have a wider genotoxic/mutagenic profile of the anticancer drugs selected, SOS Chromotest and Salmonella mutagenicity assay were performed. The comet results showed that all drugs induced DNA damage, in both Cladocerans, with environmental concern; indeed Doxorubicin induced DNA damage in the order of tens of ng L −1 in both crustaceans, as well as 5-flurouracil in C. dubia and cisplatin in D. magna . In the SOS Chromotest all drugs, except imatinib, were able to activate the repair system in Escherichia coli PQ37 while in the Salmonella mutagenicity assay, doxorubicin was the only drug able to cause direct and indirect frameshift and base-pair substitution mutations. Comet assay was the most sensitive tool of genotoxic exposure assessment, able to detect in vivo the adverse effects at concentration lower than those evaluated in vitro by bacterial assays.

  • Ecotoxicological evaluation of caffeine and its derivatives from a simulated chlorination step
    'Elsevier BV', 2014
    Co-Authors: Armando Zarrelli, Alfredo Parrella, Margherita Lavorgna, Emma Criscuolo, Marina Dellagreca, Maria Rosaria Iesce, Fabio Temussi, Luigi Schiavone, Lucio Previtera, Marina Isidori
    Abstract:

    Caffeine is ubiquitous in surface and ground waters and it has been proposed as a marker of the anthropogenic pressure on the environment. Sewage treatment plants based on active sludges seem to be not very efficient in its complete removal from effluents while addnl. disinfection treatments by chlorination are able to do it. In a simulation of the chlorination step herein we report that caffeine is transformed in six byproducts: 8-???chlorocaffeine, 1,???3-???dimethyl-???5-???azabarbituric acid, N,???N'-???dimethylparabanic acid, N,???N'-???dimethyloxalamide, N-???methylurea and N,???N'-???dimethylurea. The ecotoxicity of caffeine and identified compds. was evaluated on the rotifer Brachionus calyciflorus and the alga Pseudokirchneriella subcapitata to assess acute and chronic toxicity, while SOS Chromotest and Ames Test were used to detect the genotoxic potential of the investigated compds. Moreover, we assessed the possible antigenotoxic effect of the selected compds. using SOS Chromotest after co-???incubation with the std. genotoxin, 4-???nitroquinoline 1-???oxide. Chronic exposure to these compds. caused inhibition of growth population on the rotifer while the algae seemed to be unaffected. Results indicated that caffeine (1)???, N,???N'-???dimethyloxamide (4) and N,???N'-???dimethylparabanic acid (5) reduced ??-???galactosidase activity in comparison with pos. control, both at 1 and 5 mg???/L of 4-???NQNO with a good dose-???response

  • ecotoxicity of naproxen and its phototransformation products
    Science of The Total Environment, 2005
    Co-Authors: Marina Isidori, Alfredo Parrella, Margherita Lavorgna, Lucio Previtera, Angela Nardelli, Maria Rubino
    Abstract:

    The occurrence of pharmaceuticals in the environment is of great concern and only few data are available about the adverse effects of such molecules and their derivatives on non-target aquatic organisms. This study was designed to assess the toxic potential of Naproxen, a nonsteroidal anti-inflammatory, Naproxen Na, its freely water soluble sodium salt and their photoproducts in the aquatic environment. Bioassays were performed on algae, rotifers and microcrustaceans to assess acute and chronic toxicity. Furthermore, possible genotoxic effects of photoderivatives were investigated using SOS Chromotest and Ames fluctuation test. The results showed that photoproducts were more toxic than the parent compounds both for acute and chronic values, while genotoxic and mutagenic effects were not found. These findings suggested the opportunity to consider derivatives in ecotoxicology assessment of drugs.

  • toxic and genotoxic evaluation of six antibiotics on non target organisms
    Science of The Total Environment, 2005
    Co-Authors: Marina Isidori, Margherita Lavorgna, Angela Nardelli, Luigia Pascarella, Alfredo Parrella
    Abstract:

    The ecotoxicity of the following six antibiotics on aquatic organisms was investigated: Erythromycin, Oxytetracyclin, Sulfamethoxazole, Ofloxacin, Lincomycin and Clarithromycin. Bioassays were performed on bacteria, algae, rotifers, microcrustaceans and fish to assess acute and chronic toxicity, while SOS Chromotest and Ames test were used to detect the genotoxic potential of the investigated drugs. For risk assessment, the environmental impact was calculated by MEC/PNEC ratio using the available data from the literature regarding their occurrence in the aquatic environment and the toxicity data obtained from the bioassays performed. The ecotoxicological results showed that acute toxicity was in the order of mg/L while, for the chronic data the antibiotics were bioactive at concentrations in the order of μg/L, mainly for the algae. Drugs investigated were one or two order of magnitude less active against rotifers and crustaceans. Ofloxacin was the only genotoxic compound and Sulfamethoxazole, Ofloxacin and Lincomycin were mutagenic. As for environmental risk, the macrolides were found to be the most harmful for the aquatic environment.

Karamova N. - One of the best experts on this subject based on the ideXlab platform.

  • Induction of the SOS-response in test bacteria by bacillus intermedius RNase
    2020
    Co-Authors: Ivanchenko O., Karamova N., Kipenskaya L.
    Abstract:

    This paper deals with the induction of the SOS-functions of a bacterial cell by the exogenous ribonuclease of Bacillus intermedius. Two test systems were employed, which made it possible to quantitatively estimate SOS-response induction activity in gram-positive and gram-negative bacteria. It was established that the catalytically active enzyme elicits the SOS-response in the cells of Escherichia coli PQ 37 and causes prophage induction in the lysogenic strain Bacillus subtilis 168 cplOS WT (a phenomenon related to the SOS-response). An enzyme with a His101Glu-substituted active center, exhibiting residual catalytic activity, failed to induce the SOS-response in an SOS-Chromotest with E. coli PQ 37, indicating dependence of the SOSinducing effect of the enzyme on its catalytic activity. It is suggested that the effect of active ribonuclease on membrane-bound and cytoplasmic RNA causes a change in the nucleotide pool and, as a consequence, elicits the SOS-response of the cell

  • Induction of the SOS-response in test bacteria by Bacillus intermedius RNase
    2020
    Co-Authors: Ivanchenko O., Karamova N., Kipenskaya L.
    Abstract:

    This paper deals with the induction of the SOS-functions of a bacterial cell by the exogenous ribonuclease of Bacillus intermedius. Two test systems were employed, which made it possible to quantitatively estimate SOS-response induction activity in gram-positive and gram-negative bacteria. It was established that the catalytically active enzyme elicits the SOS-response in the cells of Escherichia coli PQ 37 and causes prophage induction in the lysogenic strain Bacillus subtilis 168 φ105 WT (a phenomenon related to the SOS-response). An enzyme with a His 101Glu-substituted active center, exhibiting residual catalytic activity, failed to induce the SOS-response in an SOS-Chromotest with E. coli PQ 37, indicating dependence of the SOS-inducing effect of the enzyme on its catalytic activity. It is suggested that the effect of active ribonuclease on membrane-bound and cytoplasmic RNA causes a change in the nucleotide pool and, consequently, elicits the SOS-response of the cell. © 1997 MAHK Hayka/Interperiodica Publishing

  • An investigation of antigenotoxic properties of plant extracts of Chelidonium majus L., Plantago major L. and Tussilago farfara L
    2020
    Co-Authors: Karamova N., Fatykhova D., Abdrakhimova Y., Il'inskaya O.
    Abstract:

    The antigenotoxic properties of the sap from three medicinal plants, the greater celandine (Chelidonium majus L.), the greater plantain (Plantago major L.), and coltsfoot (Tussilago farfara L.), were studied using two bacterial test systems (SOS Chromotest and Rec assay). It was determined using the combined effect of the plant sap and model genotoxicants on the cells of test strains that the plant sap of the greater celandine reveals a dismutagenic effect decreasing the genotoxic effect of nalidixic acid in the SOS Chromotest and furacilin in the Rec assay. The plants sap of the greater celandine and coltsfoot (in 1: 10 and 1: 100 dilutions) demonstrated a bioantimutagenic effect in the SOS Chromotest because pre-incubation of the E. coli PQ37 cells test strain with the sap of these plants resulted in a significant decrease of the genotoxic effect of nalidixic acid. The antigenotoxic effect of the greater plantain sap was not statistically significant in both test systems. Possible mechanisms of determining the antigenotoxic properties of the plant sap from greater celandine and coltsfoot are discussed. © 2011 Pleiades Publishing, Ltd

  • Study of Genotoxic Effects of Tonarol
    2020
    Co-Authors: Karamova N.
    Abstract:

    Genotoxic effects of 2,6-di-tret-butyl-4-methylphenol (tonarol) were studied using four test systems: the Ames test, the SOS Chromotest, the cytogenetic test with rootlets of onion (Allium cepa), and the in vivo micronucleus test. Tonarol did not affect gene mutation induction in Salmonella typhimurium tester strains, the SOS response in the Escherichia coli strain PQ37, chromosomal aberrations in cells of onion (Allium cepa) rootlets, and micronuclei in erythrocytes of peripheral blood of CBA x C5713 L/G mice. Tonarol induced cell division in A

  • Study of Genotoxic Effects of Tonarol
    2020
    Co-Authors: Karamova N., Ivanchenko O., Ermolaev A., Gershanov F., Khamitov B.
    Abstract:

    Genotoxic effects of 2,6-di-tret-butyl-4-methylphenol (tonarol) were studied using four test systems: the Ames test, the SOS Chromotest, the cytogenetic test with rootlets of onion (Allium cepa), and the in vivo micronucleus test. Tonarol did not affect gene mutation induction in Salmonella typhimurium tester strains, the SOS response in the Escherichia coli strain PQ37, chromosomal aberrations in cells of onion (Allium cepa) rootlets, and micronuclei in erythrocytes of peripheral blood of CBA × C5713 L/G mice. Tonarol induced cell division in A. cepa rootlets at concentrations of 25-100 mg/l, indicating that this compound can affect mechanisms of cell division, growth, and differentiation

B Jolibois - One of the best experts on this subject based on the ideXlab platform.

  • detection of hospital wastewater genotoxicity with the SOS Chromotest and ames fluctuation test
    Chemosphere, 2003
    Co-Authors: B Jolibois, M Guerbet, S Vassal
    Abstract:

    The genotoxic potential of Rouen University Hospital wastewater was evaluated by the SOS Chromotest (on Escherichia coli PQ37) and Ames fluctuation test on Salmonella typhimurium strains TA 98 and TA 100 without metabolic activation. The samples were taken during the hospital maximal activity period (8:00 a.m. to 6:00 p.m.) over three one-week periods of the year. The simultaneous use of SOS Chromotest and Ames fluctuation test allows us to carry out a preliminary screening of the hospital wastewater and to gain some insight by which mechanism the genotoxic compounds act. Out of a total of 18 daytime unconcentrated samples tested, 10 (55%) are positive in at least one assay. The two tests have different sensitivity. Indeed, nine genotoxic samples (50%) are detected by the Ames test, and four (22%) by the SOS Chromotest. Distribution and intensity of the genotoxic response are different at the three periods. In order to explain this phenomenon, the influence of the rain levels is discussed. This work showed that the hospital wastewater samples tested were overall genotoxic, the response intensity being inflected by the pluviometry. Efforts are now under way to try to identify one or several genotoxic compounds in order to take precautionary measures to limit their release in hospital wastewaters.