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Composition of norfloxacin-resistant bacteria and isolation of norfloxacin-degrading bacteria in subtropical aquaculture ponds in China

Mao Lutian, Chen Lifen, Wang Xirui, Xu Zhongbao, Ouyang Hui, Huang Biyou, Zhou Libin

Archives of Environmental Protection

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2022

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Vol. 48, no. 4

95--101

EN

To analyze the composition of norfloxacin-resistant bacteria and norfloxacin-degrading bacteria in pond water and sediment in subtropical China, the composition of antibiotic resistant bacteria in pond water and sediment enriched with norfloxacin-containing medium was analyzed by high-throughput sequencing. Sediment and water samples were collected from 3 fish ponds in subtropical China, and domesticated with norfloxacin, subsequently norfloxacin-resistant bacteria through high-throughput sequencing of 16S rDNA, and isolated norfloxacin--degrading bacteria. Our results showed that the pond sediment and water contain a variety of norfloxacin-resistant bacteria, mainly from Proteobacteria, Bacteroidetes, Actinobacteria, Firmicutes, and Chloroflexi. Moreover, we isolated two norfloxacin-degrading bacteria (NorXu-2 and NorXu-3). The norfloxacin-degrading rate by NorXu-2 and NorXu-3 in the culture mediums with 200 μg/mL was the highest, which was up to 49.71% and 35.79%, respectively. When the norfloxacin concentration was 200 μg/mL, NorXu-2 and NorXu-3 had the best norfloxacin- -degrading effect at pH of 6, and the degradation rates were 53.64% and 45.54%, respectively. Moreover, NorXu-3 exhibited a good tolerance to high NaCl concentration. These results not only provided basic data for the follow-up study of the molecular mechanism of antimicrobial microbial degradation, but also provided potential norfloxacin degrading bacteria for norfloxacin removal and bioremediation in aquaculture environment.

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Aerobic biodegradation of norfloxacin and ofloxacin by a microbial consortium

Jałowiecki Łukasz, Płaza Grażyna, Ejhed Helena, Nawrotek Monika

Archives of Environmental Protection

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2019

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Vol. 45, no. 4

40--47

EN

Since fluoroquinolone (FQ) antibiotics are extensively used both in human and veterinary medicine their accumulation in the environment is causing increasing concern. The aim of the study was to isolate a microbial consortium resistant to ofloxacin and norfloxacin and able to biodegrade both antibiotics. Green compost was used as a source of microorganisms. The biodegradation efficiency was monitored by changes of antibiotics concentrations and toxicity. The microbial consortium was composed of two bacterial isolates: Klebsiella pneumoniae (K2) and Achromobacter sp. (K3) and two fungi Candida manassasensis (K1) and Trichosporon asahii (K4). All the isolates were characterized as highly resistant to both antibiotics – ofloxacin and norfloxacin. FQs were supplied individually into the culture medium in the presence of an easily degradable carbon source – glucose. Biodegradation of norfloxacin was much faster than ofloxacin biodegradation. During 20 days of the experiment, the norfloxacin level decreased by more than 80%. Ofloxacin was generally biodegraded thereafter at relatively slow biodegradation rate. After 28 days the ofloxacin level decreased by 60%. Similarly, the toxicity of biodegraded antibiotics decreased 4-fold and 3.5-fold for norfloxacin and ofloxacin, respectively. The ability of the bacterial-fungal consortium to degrade antibiotics and reduce toxicity could help to reduce environmental pollution with these pharmaceutical.

PL

Antybiotyki to zróżnicowana grupa związków, która nie ma konkretnych uregulowań prawnych, dotyczących ich występowania w środowisku, zarówno wodnym jak i glebowym. Farmaceutyki przedostają się do środowiska m.in. wraz ze ściekami oczyszczonymi z oczyszczalni ścieków i jako substancje czynne biologicznie stanowią poważne zagrożenie dla organizmów żywych. Ich akumulacja w środowisku prowadzi do nieodwracalnych zmian w ekosystemach oraz szerzenia się zjawiska oporności wśród mikroorganizmów. Fluorochinolony (FQ) to syntetyczne substancje antybakteryjne o zwiększonym potencjale farmakokinetycznym i szerokim spektrum działania. FQ to jedna z najszybciej rozwijających się klas antybiotyków coraz częściej stosowanych zarówno w szpitalach, jak i w społecznościach lokalnych w leczeniu różnego typu zakażeń. Norfloksacyna i ofloksacyna to FQ II generacji o podobnej budowie strukturalnej wykazujące aktywność głównie wobec bakterii Gram-ujemnych. Ze względu na swoja budowę antybiotyki te w niewielkim stopniu są rozkładane w środowisku, przez długi czas kumulują się w wodzie i w glebie, oddziałując w na organizmy żywe. Celem pracy była ocena toksyczności ofloksacyny i norfloksacyny po biodegradacji przez zespół mikroorganizmów wyizolowany z kompostu. Proces biodegradacji przeprowadzono w bioreaktorach New Brunswick™ BioFlo® 415 o pojemności 5,5 l. Stopień degradacji określono za pomocą chromatografi i cieczowej w odwróconym układzie faz. Do oceny toksyczności wykorzystano test Microtox® oparty na pomiarach aktywności bakterii luminescencyjnych Vibrio fischeri.

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Facile assay method for norfloxacin and ciprofloxacin by sequential injection chromatography

Elgorashe R. E. E., Idris A. M., Abdelrahman M. A., Saeed A. E. M.

Acta Chromatographica

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2014

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Vol. 26, no. 2

321--334

EN

Sequential injection chromatography (SIC) is a simple, inexpensive, portable, reagent-saving, and environmentally benign separation technique. This paper reports the development of a facile assay method for norfloxacin (NF) and ciprofloxacin (CF) in their formulations (tablets and eye drops) using SIC. The analytes were rapidly chromatographed on a short C18 monolithic column (4.6 × 50 mm) at a flow rate of 30 μL s -1. An isocratic mode was adopted. The optimum mobile phase composition was 90% water, 10% acetonitrile, and 0.3% triethylamine at pH 3.0. Miniaturized fiber optic spectrometric devices were coupled to the SIC system for UV detection at 280 nm. Sufficient separation with a resolution of 1.6 and numbers of theoretical plates of more than 1500 was achieved. Additionally, acceptable peak shapes with peak symmetries of 0.89 and 0.92 for NF and CF, respectively, were obtained. The method was validated and found to be reliable (the recovery was 98.0–100.6%) and precise (the RSDs of intra-/inter-day precision were less than 2.0%). The method is also sensitive. The limits of detection were less than 0.27 μg mL -1. The provided method could be considered an industrial scale since the sample frequency was seven samples h -1 and the total volume of consumed reagents was 11.5 mL.

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Quantitative determination of fluoroquinolinic antibiotics: pefloxacin, norfloxacin, ciprofloxacin and ofloxacin in pharmaceutical preparations and human serum by high-performance liquid chromatography using multi-wavelength calibration technique

Siddiqui F. A., Arayne M. S., Sultana N., Qureshi F., Mirza A. Z., Shehnaz H.

Chemia Analityczna

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2009

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Vol. 54, No. 6

1465-1485

EN

The objective of this research was to develop and validate an analytical method for quantitative determination of fluoroquinolones using multivariate calibration technique in order to reduce chance errors. Simple and rapid chromatographic method for quantitative determination of four quinolone antibiotics, separately in pharmaceutical formulations and human serum, was developed and validated. The studied fluoroquinolones were pefloxacin, norfloxacin, ciprofloxacin and ofloxacin. These quinolones were analysed using a Nucleosil C18 (10 μrn, 25 cm x 0.46 cm) column, a water-acetonitrile (50:50, v/v) mobile phase of pH 2.9 adjusted with phosphoric acid, and propylparaben as an internal standard. The flow rate was 1.0 mL min1. The analyses were performed at the room temperature (24 š 2°C) using a UV detector at the wavelengths 260,265,270,275 and 280 nm. All fluoroquinolones were separated within 10 min. The calibration curves were linear (≥ 0.9999) over the concentration range 20-10000 ng mL-1. Relative standard deviation (RSD) was 1.56%, minimum recovery was 98.65 % and maximum recovery equaled to 100.81%.

PL

Celem pracy jest opracowanie i walidacja metod ilościowego oznaczania fluorochinolonów przy wykorzystaniu wieloczynnikowej techniki kalibracji, pozwalającej na zminimalizowanie błędu oznaczenia. Opracowano i zwalidowano proste i szybkie metody chromatograficzne ilościowego oznaczania czterech antybiotyków chinolonowych, również w formu-lacjach farmaceutycznych i w ludzkim osoczu. Badane fluorochinolony to pefloksacyna, norfloksacyna. ciprofloksacyna i ofloksacyna. Antybiotyki analizowano stosując kolumnę Nucleosil C18(10μm, 25 x 0,46 cm), jako fazę ruchomą, użyto mieszaninę woda-acetonitryl (50:50, v/v) o pH 2,9 (ustalanym za pomocą kwasu fosforowego) oraz propyloparaben jako wzorzec wewnętrzny. Przepływ wynosił l ,0 mL min-1. Analizy prowadzono w temperaturze pokojowej (24 š 2°C) stosując detektor UV przy długościach fal 260, 265, 270, 275 i 280 nm. Rozdzielenie wszystkich fluorochinolonów uzyskano w ciągu 10 min. Krzywe kalibracyjne były liniowe (r > 0,9999) w zakresie 20 -l 0000 ng mL18. Względne odchylenie standardowe (RSD) było < 1,56%, minimalny odzysk wynosił 98,65% a maksymalny 100,81%.