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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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Sustain release Formulation and Evaluation of Ofloxacin floating delivery system

Patel A. J., Naik D. R., Raval J. R.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 12

69--83

EN

Floating tablets has been accepted as a process to achieve controlled drug delivery by prolonging the residence time of the dosage form at the site of absorption, thereby improving and enhancing the bioavailability of drug. The objective of present study outlines the development and characterization the floating drug delivery system of Ofloxacin to enhance its bioavailability and therapeutic efficacy, using different grades of polymer along with effervescent agent sodium bicarbonate and citric acid. Ofloxacin is a synthetic chemotherapeutic second-generation antibiotic of the fluoroquinolone class. Different tablet formulations were formulated by wet granulation technique and were evaluated for physical parameters like Tablet Thickness, Hardness, % Friability, Weight variation, Content uniformity, In vitro buoyancy, Swelling index, In vitro dissolution study and drug release mechanisms. As the concentration of the polymer in the formulations increased the release of drug decreased. Hence it was considered as suitable candidate for formulation as floating drug delivery system. Different kinetic models were applied to drug release data in order to evaluate release mechanisms and kinetics. The optimized formula F4 showed better sustained drug release with good floating properties and fitted best to be Korsmeyer-Peppas model with R2 value of 0.9575. As the n value for the Korsmeyer- Peppas model was found be more than 0.5 it follows Non-Fickian diffusion mechanism. FTIR result showed that there is no drug excipients interaction.

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Comparative study of RP-HPLC versus TLC-spectrodensitometric methods applied for binary mixtures of fluoroquinolones and corticosteroids

Elgizawy S. M., Hassan N. Y., Lotfy H. M., Saleh S. S.

Acta Chromatographica

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2014

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Vol. 26, no. 3

439--456

EN

Reversed phase high-performance liquid chromatography (RP-HPLC) and thin-layer chromatography (TLC)-spectrodensitometric methods have been developed and validated for the separation and quantitation of two binary mixtures: Ofloxacin (OFX) and dexamethasone (DXM) in eye preparation; ciprofloxacin hydrochloride (CIP) and hydrocortisone (HYD) in ear preparation. The linearity ranges of RP-HPLC methods were found to be (2.5–45 μg mL-1) for OFX, (2.5–50 μg mL-1) for DXM and (1–8 μg mL-1) for both CIP and HYD. The percentage recoveries/relative standard deviation (RSD) were found to be 100.36/1.38, 100.13/1.49, 99.98/0.61 and 100.28/1.27, respectively. The linearity ranges of TLC-spectrodensitometric methods were found to be (0.5–2 μg band-1), (0.5–3.5 μg band-1), (0.2–1.6 μg band-1), and (0.6–2 μg band-1 for OFX, DXM, CIP, and HYD, respectively. The percentage recoveries/RSD were found to be 99.98/1.06, 99.93/1.18, 99.74/1.27, and 99.94/1.54, respectively. A comparative study was conducted to show the advantages of the proposed methods which showed that the TLC-spectrodensitometric methods were simpler, more sensitive, and economic, while RP-HPLC methods were more precise and robust. The methods were validated in compliance with the ICH guidelines and were successfully applied for determination of the selected drugs in their laboratory-prepared mixtures and commercial dosage forms.

4

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%.