Tetracycline Group Of Antibiotics Research Articles

Determination of Tetracycline Group Antibiotics Residues in the Tigris River and Agricultural Lands Fed by Tigris River and Reduction of Unconscious Use of Antibiotics

The recent increase in environmental pollutants is contaminating important natural resources and causing irreversible damage. Due to the limitations of traditional treatment techniques, studies on the problem of micro pollutant contamination of water resources have increased significantly. Antibiotics used in medicine and veterinary medicine cause significant pollution of water resources as residues of these contaminants remain unchanged in the aqueous environment. This has recently been recognised as a global environmental health threat. The ecosystem is vulnerable to residues of these contaminants from agriculture and aquaculture. In this study, the presence of tetracycline group antibiotics, the most commonly used in veterinary medicine, was determined in the Tigris river. This is the first study to date in which antibiotics from the tetracycline group have been identified in the Tigris river. Water samples were taken from 16 different points (80 samples) along the river. Sampling points were grouped as abattoirs, livestock markets, farmland, cafes and bridges near settlements. The samples were analysed for the presence of tetracycline (TC), oxytetracycline (OTC) and chlortetracycline (CTC). With a concentration range of 0.037 to 1.756 ng/L, oxytetracycline was found in 14 of the 16 sites. A concentration of 0.004–0.014 ng/L of tetracycline was found in five samples. Chlortetracycline was found in six samples, with concentrations ranging from 0.015 to 0.097 ng/L. According to the study, the tetracycline family of antibiotics was found in the water samples, and oxytetracycline was present in the highest concentrations in most of them.

Modified powder of Corchorus capsularis as a new adsorbent for removal of tetracycline group antibiotic from water

AbstractThis study prepared a novel adsorbent from Corchorus capsularis modified powder for the removal of the tetracycline group (tetracycline ‐TC, oxytetracycline ‐OTC, chlortetracycline ‐CTC) in aqueous solution. Corchorus capsularis powder was pre‐treated with 15% sodium hydroxide (COC), then reformed by a mixture of 0.15 mol L−1 sodium bisulfide (SB) and 0.2 mol L−1 ammonium peroxydisulfate (APS). This adsorbent was embedded with monoacrylamide (AM) at ratio AM/COC = 1/1 at 60 °C for 2.5 h. After modification with AM (BTA), the surface area of the adsorbents increased from 1.53 to 2.79 m2 g−1, while the pore size of the adsorbents decreased from 36.95 to 11.85 nm. The study also investigated the effects of pH, adsorbent dose and temperature on the adsorptive removal process. Tetracycline concentrations were determined using liquid chromatography–tandem mass spectrometry (LC–MS/MS). The kinetics and isotherms of adsorption performance were examined using a variety of models, including pseudo‐first‐order kinetic (PFO), pseudo‐second‐order kinetic (PSO), Freundlich, Langmuir, and Dubinin–Radushkevich isotherms (DRM). The experimental data fitted very well with the pseudo‐second‐order kinetic model. The maximum adsorption bulks of TC, OTC, CTC following Langmuir isotherm model were 1.25, 0.83, 1.43 mg g−1, respectively. The adsorption constants Kp of TC, OTC, and CTC from the Freundlich isotherm model were 15.36, 21.80, and 22.08 mg1−nLng−1, respectively. The mean free energy E (kJ mol−1) of TC, OTC, and CTC from DRM was 4.35, 4.20, and 4.57, respectively. The results indicated that modified Corchorus capsularis powder had significant potential as a new adsorbent material for removing antibiotics from aqueous solutions.

QUALITY CHARACTERISTICS OF RAW MILK SAMPLES PURCHASED FROM AUTOMATIC MİLK VENDING MACHINES IN NİĞDE PROVINCE

In the regulation published by the Ministry of Agriculture and Forestry in Turkey, it is stated that only automatic milk machines can be used to put raw milk on sale. This study aims to examine some physical, chemical and microbiological properties of a total of 40 raw milk samples sold in automatic vending machines and unpackaged, by egulations in Niğde province, and to compare the milk samples according to the retailer from which they were purchased. The study also aimed to quantitatively determine carbonate and hydrogen peroxide residues in milk samples and the presence of beta-lactam and tetracycline group antibiotics with a commercial kit. At the end of the study, the average value of lactic acid (%) density, fat, protein, non-fat dry matter, lactose, freezing point and pH values of the samples were determined as 0.153% ± (0.022); 1.028± (0.03) g/ml; 3.525%± (0.656); 3.5%± (0.107); 9% 4± (0.277); 5.134± (0.152); -0.549°C ± (0.018) and 6.55 ± (0.102) respectively. As a result of microbiological analysis of milk, the average number of total aerobic mesophilic organisms, coliforms, fecal coliforms, yeast-molds and micrococci-staphylococci was determined as 5.38 ± (0.47); 3.73 ± (1.11); 2.76 ± (1.66); 2.33 ± (1.86) and 4.29± (1.20) log cfu/ml respectively. Carbonate, hydrogen peroxide, beta-lactam and tetracycline antibiotic residues could not be detected in the milk samples. The fact that some of the results obtained in the study were outside the limits specified in the codexes and different from the study average reveals that the milk sold in businesses selling street milk should be analyzed regularly.

A rare case of minocycline induced diffuse hyperpigmentation

Minocycline, a tetracycline group of antibiotics, is commonly used to treat various infections, dermatological conditions and rarely used to treat rheumatoid arthritis. Prolonged use of minocycline in higher doses can rarely cause skin hyperpigmentation. Minocycline-induced hyperpigmentation can also involve the sclera and retina in the eyes.

IMPLEMENTATION OF THE SYSTEM OF HONEY SAFETY CONTROL ON THE EXAMPLE OF ANALYZING OF RESIDUES OF TETRACYCLINE GROUP ANTIBIOTICS

The National Reference Laboratory of Drug Residues Control has implemented a system of "classical" honey safety control based on the parameters of antimicrobial drug residues: samples testing by the screening enzyme-linked immunosorbent assay (ELISA) method and, in the case of positive or possibly positive samples occurring, – retesting by confirmatory UPLC-MS/MS multi-method developed in the laboratory. The article presents the results of ELISA screening method validation for the determination of residual amounts of tetracycline group antibiotics (tetracycline, oxytetracycline, chlortetracycline, doxycycline) in honey samples using Tetracyclin® RIDASCREEN test kits by R-Biopharm (Germany) and Oxytetracycline ELISA by EuroProxima (the Netherlands) and its verification by means of the confirmatory method.
 In accordance with the Commission Implementing Regulation (EU) 2021/808, the validation of test kits proposed by the manufacturers was carried out taking into account the minimum required limit of detection. The fitness-for-purpose of the methods was confirmed based on the establishment of main validation parameters for screening methods (technical threshold and cut-off factor) using control (blank) and fortified honey samples with standard solutions of tetracycline at the level of ½ of the minimum required limit of detection, according to the "added-received" criterion. The proposed methods are the simple in carrying out, time- and cost-effective, which are their main advantages.
 The reliability of the results obtained by the proposed methods was verified using the developed confirmatory UPLC-MS/MS multi-method. The results of comparative studies of control (blank) honey samples and fortified with a standard solution of tetracycline antibiotics at the level of 2.5 and 5.0 μg/kg, as well as the results of the interlaboratory testing with the accredited laboratory (Germany) are presented.

Detection and correlation of antimicrobial resistance pattern in Enterobacteriaceae from UTI patients in GMERS Medical College, Gujarat

Background: Bacterial resistance to antibiotics is a growing public health threat worldwide. The increasing rate of antimicrobial resistance among bacterial pathogens causing both hospital- and community-acquired infections is a serious threat to public health world-wide. This inappropriate and non-judicious usage of antibiotics has resulted in the development of worldwide antibiotic resistance in bacteria, leading to the emergence of multi-resistant strains of bacterial pathogens. This study focuses on the prevalence of antibiotic resistance in the Enterobacteriaceae group of organisms in urine samples and also detects various methods of antibiotic resistance. Antibiotic resistance detection may be useful for epidemiological and research purposes, as well as for preventing the spread of drug-resistant organisms within hospitals through good infection control practices. Aims and Objectives: The aim of the study was to detect occurrence of β-lactamases, extended-spectrum beta-lactamases (ESBL) and Carbapenemase by phenotypic methods in Enterobacteriaceae from urine samples along with pattern of antibiotic resistance for various antibiotics in them. Materials and Methods: A descriptive study was conducted at a tertiary-care hospital. Testing of ESBL and carbapenemase production detection done according to CLSI (M100) guideline by the Kirby-Bauer disk diffusion method, combination disc diffusion test, and modified Carbapenem inactivation method. Results: A total of 220 Enterobacteriaceae organisms were isolated from processed urine samples of tertiary care Hospitals. Rate of cephalosporin resistance in ESBL and carbapenem-resistant Enterobacteriaceae (CRE) is more than 90% while in non-ESBL more than 70% and in non-CRE 75–80%. Carbapenem resistance in ESBL and non-ESBL is the same. Resistance to fluoroquinolone group, Aminoglycoside group, and Cotrimoxazole and Tetracycline group of antibiotics were more noticed in ESBL and carbapenemase producing organisms. In our study, fosfomycin and Nitrofurantoin are effective treatment in case of ESBL and CRE producing organism. Conclusion: The ESBL and Carbapenemase producing isolates were multi-drug resistant making therapeutic choices limited. Fosfomycin and Nitrofurantoin are effective treatment in multidrug resistance urinary tract infection.

Sade ve Aromalı UHT Sütlerde Tetrasiklin Kalıntılarının Araştırılması

In this study, tetracycline group antibiotic residue was investigated in plain and flavored UHT milk of different brands. A total of 90 UHT milk samples (62 plain and 28 flavored) were analyzed by ELISA method. Tetracycline residues were detected in all samples as a result of the analysis. The mean level of tetracycline was determined as 6.98±0.38 ppb in plain milk and 6.53±0.48 ppb in flavored milk. Residue levels in analyzed UHT milk were found to comply with the legal limits announced by the European Union (EU) commission and Turkish Food Codex Communiqué.

Oxidative removal of oxytetracycline by UV-C/hydrogen peroxide and UV-C/peroxymonosulfate: Process optimization, kinetics, influence of co-existing ions, and quenching experiments

Oxytetracycline (OTC) is a tetracycline group antibiotic with high environmental pollution potential and is resistant to conventional treatment processes. This study provides an environmentally friendly and efficient OTC treatment by ultraviolet (UV)-based advanced oxidation processes. UV irradiation was used for the activation of hydrogen peroxide (HP) and peroxymonosulfate (PMS). In the first stage of the study, control experiments were conducted and the effect of initial pH on the UV/HP and UV/PMS in OTC removal was evaluated. In the following part, variables of the UV/HP and UV/PMS were optimized by the Box-Behnken design. The optimum conditions of the UV/HP process were as follows: 6.5 mg/L initial OTC concentration, 3.50 mM HP dose, and 45.4 min reaction time. The optimum parameters of the UV/PMS process were: 5 mg/L initial OTC concentration, 3.69 mM PMS dose, and 42.75 min reaction time. 72.8 % and 50.96 % OTC removal efficiency were achieved with the validation experiments by the UV/PMS and UV/HP processes, respectively. Kinetic studies showed that Cl− and HCO3− ions have a positive effect whereas SO42− has a negligible effect on the reaction rate of both processes. NO3− has a positive effect on the UV/HP process and a negligible effect on the UV/PMS process. According to the radical scavenging experiments, hydroxyl radicals were dominant in the UV/HP process while in the UV/PMS process both hydroxyl and sulfate radicals were involved. Both processes were effective in OTC removal; however, the UV/PMS process is more efficient and cost-effective.

Comparative potentials of H2- and O2-MBfRs in removing multiple tetracycline antibiotics

Tetracycline antibiotics are broad spectrum antimicrobial compounds commonly used in human therapy and animal growth. This study has focused on the simultaneous removal of three tetracycline group antibiotics in co-existence in aquatic environments, including tetracycline (TC), oxytetracycline (OTC), chlortetracycline (CTC), and nitrous compounds in hydrogen (H2) and oxygen (O2) based membrane biofilm reactors (MBfRs). The treatment performances of MBfRs were comprehensively investigated by considering the effect of the hydraulic retention time (HRT) and surface loadings of tetracycline mixture. The results demonstrated that the average nitrification and denitrification efficiencies were 96% and 98% in H2-MBfR and O2-MBfR, respectively. The highest removal efficiencies for TC, OTC, and CTC in O2-MBfR were 52.5%, 54.83%, and 70.67%, while they were 92.5%, 90.5%, and 99.25% in H2-MBfR, respectively. The microbial analysis results showed that the dominant bacterial species in the biofilm of O2 and H2-based MBfRs belonged to the phyla Bacteroidetes and Proteobacteria. The findings of this study suggest that the MBfR process is an efficient alternative to remove tetracycline mixture and simultaneous nitrogen removal.

EFFECT OF MINOCYCLINE AND MINOSCYCLINE+METFORMIN ON DIABETES-RELATED DEPRESSION

Objective: Minocycline is a second-generation tetracycline group antibiotic that acts on the central nervous system. Minocycline reduces microglial activation and has anti-inflammatory, anti-apoptotic, and antioxidant properties. Recently, it has been proposed that there is a bidirectional relationship between diabetes and depression and that inflammation is one of the common pathways in their pathophysiology. The effects of minocycline on depression were then investigated. This study aimed to reveal the effects of minocycline alone or in combination with metformin, which is used in the treatment of diabetes, on diabetes-related depression. Material and Method: For this purpose, to establish a human-like type 2 diabetes model in mice, streptozotocin (STZ) (50mg/kg) was administered once a day for five consecutive days after a 4-week high-fat diet. Animals with blood glucose levels ≥200 mg/dl were considered diabetic and employed in this experiment. Minocycline (40 mg/kg), fluoxetine (20 mg/kg), and metformin (200 mg/kg) were given once a day for 7 days two weeks after STZ injection. After the drug injections were completed, an open field test was used to determine locomotor activity and a forced swimming test was used to determine depression level. Result and Discussion: It was concluded that diabetes and the drugs administered did not induce a significant change in locomotor activity, and that the minocycline and minocycline-metformin combination was at least as effective as fluoxetine in treating depression. It is recognized that the initiation of antidepressant effects in a short period is critical for patient adherence to therapy and diabetes prognosis. In conclusion, antidepressant-like effects of subchronic minocycline treatment appear to be potent as classical antidepressants. The mechanisms underlying minocycline's effects on mood should be broadly investigated to increase our understanding of depression and unveil potential novel therapies in depression management.

Prevalence and Quantitative Analysis of Antibiotic Resistance Genes (ARGs) in Surface and Groundwater in Meandering Part of the Kelani River Basin in Sri Lanka.

Nearly 80% of the population in the Colombo district fulfill their major requirement from the Kelani river. Recent studies are interoperating: most groundwater and surface water in Sri Lanka are contaminated with waterborne pathogens and antibiotics. In the present study, nine antibiotic resistance genes (ARGs) were screened which were belonging to two common groups of antibiotic: penicillin — OPR D, bla TEM, bla OXA, amp a, and amp b — and tetracycline — tet A, tet M, tet B, and tet S. The results of the study reveled that the surface and groundwater of the entire lower part of the Kelani river basin were contaminated with TC and FC (98%). None of the penicillin and tetracycline group antibiotics were detected either surface or groundwater samples except the Kelani river mouth (amoxicillin (AMX) at 0.003 ± 0.001 µg/ml). The results showed that 5 to 15% of surface water samples were positive for penicillin resistance genes (bla TEM, bla OXA, OPR D, amp a, amp b) where ~ 10% of groundwater samples were positive against tetracycline resistance genes (tet A, tet M, tet S, tet B). Among the penicillin resistance genes, the bla TEM (700.576 × 102 copy/ml) was recorded as the highest concentration where the highest tet A gene (439.875 × 102 copy/ml) was detected among the tetracycline resistance genes. Therefore, water quality management and regular monitoring are essential to maintain the quality of drinking water in the meandering part of the Kelani river basin to safeguard river water consumers.

Обработка экспериментальных данных при разделении хроматографических сигналов антибиотиков тетрациклиновой группы методом математического моделирования

Antibiotics belonging to the classes of sulfonamides, amphenicols and tetracyclines, such as tetracycline, oxytetracycline and chlortetracycline, are used to control infectious diseases of honeybees. In addition, tetracycline group antibiotics can be added directly to plants during flowering. Contamination of the flower with high concentrations of antibiotics entails the risk of transferring antibiotic residues to honey. Consequently, these antibiotics persist as contaminants in honey, and the determination of these drugs in honey samples is of great importance. Tetracyclines have a broad spectrum of activity against gram-positive and gram-negative bacteria. The basic structure of tetracyclines consists of a hydro-naphthacene framework containing four rings. Due to their possible toxic or allergic reactions and the possibility that pathogens may become resistant to these drugs, much attention has recently been paid to tetracyclines. For the detection of residual quantities of antibiotics in food products increasingly requires reliable analytical methods. The main method for determining tetracycline group antibiotics is the method of high-performance liquid chromatography, but the micro-quantities of their residual concentration and unsatisfactory chromatographic conditions, under which peaks may overlap, as well as insufficient sample preparation conditions, under which matrix components may overlap, make quantitative calculations difficult when using this method. This article describes a method for calculating the initial value of intesiveness and peak width using mathematical modeling. Based on the analysis of real chromatographic data, the applicability of this method for the quantitative determination of tetracycline group antibiotics is shown.

Tetracyclines: analysis of the Ukrainian pharmaceutical market and consumption compared to European countries

Tetracyclines are a class of antibiotics discovered over 50 years ago. These are relatively inexpensive drugs with a wide spectrum of action. Therefore, they are quite often used for the prevention and treatment of infectious diseases of humans and animals, as well as stimulants of the animal growth. The active use of antibiotics of the Tetracycline group for various indications in the 50s of the twentieth century led to the emergence of resistant microorganisms. After a long pause in the development of the tetracycline class antibiotics they are now being used more and more often for the treatment of infectious diseases caused by multidrug-resistant bacteria, for example, in osteoporotic/osteopenic bone loss, topically for the treatment of skin lesions, including acne. In 2005 and 2018 (3INN), the U.S. Food and Drug Administration (FDA) approved the use of new drugs of the Tetracycline group – Tigecycline, Omadacycline, Sarecycline and Eravacycline.Aim. To study the range of antibiotics of the Tetracycline group at the pharmaceutical market ofUkraine, as well as the volumes of their consumption in 2013-2018.Materials and methods. To analyze the assortment of Tetracycline antibiotics at the pharmaceutical market of Ukraine and worldwide, the resources of the WHO Collaborating Centre for Drug Statistics Methodology and the State Register of Medicines of Ukraine were used. Consumption was calculated using the standard ATC / DDD methodology recommended by the WHO. Results. According to theWHOCollaborationCenter for the Methodology of Statistical Analysis of Medicines, there are 17 international non-proprietary names (INNs) of the Tetracycline group antibiotics; among them 2 INNs are combined drugs. InUkraine, during six years of studies from 2013 to 2018, only 3 INNs were present at the market – Doxycycline, Tetracycline and Tigecycline, which in 2018 were represented by 14 trade names (TNs). The share of domestic drugs at the Ukrainian market decreased from 54 % in 2013 to 50 % (2018) due to the expansion of the assortment of imported TNs. The consumption of antibiotics of the Tetracycline group during the study period increased by almost 0.026 DDDs/1000 inhabitants/day. Comparing the consumption of tetracycline antibiotics inUkraine and in Europe it can be noted that inUkraine there is a slight upward trend. At the same time, inEurope in 2018, there was a insignificant decrease in consumption by an average of 0.1 DDDs/1000 inhabitants/day.Conclusions. Of the 17 INNs antibiotics of the Tetracycline group in the world, only 3 INNs are presented at the pharmaceutical market of Ukraine. On average, from 2013 to 2018, 13-14 TNs tetracyclines were presented at the pharmaceutical market of Ukraine. The consumption of tetracycline antibiotics in Ukraine over the study period increased by almost 0.026 DDDs/1000 inhabitants/day, while in Europe it remained at the same level during 2015-2017, and in 2018 it decreased slightly.

АНАЛИЗ СОДЕРЖАНИЯ АНТИБИОТИКОВ ТЕТРАЦИКЛИНОВОЙ ГРУППЫ В МЯСЕ ЦЕСАРОК

The results of the investigation of guinea fowl meat content of tetracycline group antibiotics by enzyme-linked immunosorbent assay are presented. The content of the antibiotics was confirmed by high performance liquid chromatography with mass spectrometric detection. Detection of the tetracycline in the samples of guinea fowl meat indicates the use of this antibiotic in cultivation of these birds.

Mycoplasma hominis profile in women: Culture, kit, molecular diagnosis, antimicrobial resistance, and treatment

ObjectivesMycoplasma hominis (M.hominis) infections are sexually transmitted and usually associated with urogenital and respiratory diseases. The aim of our study was to (i) detect M. hominis in the vaginal and urine samples of sexually active women using three different detection methods and (ii) to determine the antimicrobial susceptibility and recurrence after the treatment. MethodsBoth vaginal and urine samples were collected from 110 sexually active women at the Obstetrics and Gynecology Clinic, Başkent University Ankara Hospital, Turkey, between March 2015 and February 2016. The presence of M. hominis in the vaginal and urine samples was detected by in vitro culture, two biochemical diagnostics kits (Mycoplasma IES (Autobio, China) and Mycoplasma IST–2 (BioMérieux, France) and PCR. The antibiotic susceptibility of each sample was tested using the kits. The women positive for M. hominis were treated either singly or along with their sexual partners by tetracycline. ResultsM. hominis was detected in 72 of 220 (32.7%) samples (both vaginal and urine). Of which 37 showed contrary results with two different kits and then were confirmed by PCR. In 13 samples the IES kit identified M. hominis missed by IST-2, and in 8 samples the MIST-2 kit identified M. hominis missed by IES, while both kits missed 6 samples that were agar culture positive for M. hominis.” The highest susceptibility rate was observed against pristinamycin (100%), followed by 91%, 83%, and 75% for doxycycline, tetracycline, and josamycin, respectively. Twenty-five patients treated with tetracycline were followed after one month. The recurrence of M. hominis was not observed in any of the 18 cases where both sexual partners were treated but recurred in 5 of the 7 singly treated women. ConclusionsThe rate of M. hominis detection was significantly higher in the vaginal samples compared to the urine samples. The probability of detecting M. hominis by IST–2 kit was 1.18 times less than IES kit (p < 0.001). When the relationship between the samples was examined, the difference between IES and IST–2 for detecting M. hominis was statistically significant (p < 0.01). Antibiotic susceptibility tests indicated that the tetracycline group of antibiotics was effective in eliminating M. hominis when given to both the sexual partners.

Severe Type of Minocycline-Induced Hyperpigmentation Mimicking Peripheral Arterial Occlusive Disease in a Bullous Pemphigoid Patient

Minocycline is a tetracycline group antibiotic that is known to cause significant antibacterial and anti-inflammatory effects. Minocycline has been widely used to treat systemic infection, acne, dermatitis, and rosacea. However, various dose-related side effects of hyperpigmentation in whole body tissues have been reported. Three main types of minocycline-induced hyperpigmentation have been identified. In rare severe hyperpigmentation cases, drug-induced hyperpigmentation can mimic local cellulitis or peripheral arterial occlusive disease (PAOD). These processes require different therapeutic strategies. Therefore, early diagnosis is extremely important for physicians to determine the etiology of the hyperpigmentation, and subsequently discontinue the minocycline if indicated. We describe a rare case presenting a severe form of type III minocycline-induced hyperpigmentation mimicking peripheral arterial occlusive disease in a bullous pemphigoid patient.

Doxycycline inhibits pre-rRNA processing and mature rRNA formation in E. coli

In bacteria, RNase III cleaves the initial long primary ribosomal RNA transcripts/precursors (pre-rRNAs), thereby releasing the pre-16S and pre-23S rRNAs for maturation. This cleavage is specified by the double-stranded secondary structures flanking the mature rRNAs, and not necessarily by the nucleotide sequences. Inhibition of this cleavage would lead to a build-up of pre-rRNA molecules. Doxycycline has earlier been shown to bind synthetic double-stranded RNAs and inhibit their cleavage by RNase III. Since bacterial rRNA processing is primarily dependent on RNase III cleavage (which is inhibited by doxycycline), doxycycline could therefore inhibit the normal processing of bacterial rRNA. In this study, the effect of doxycycline on bacterial rRNA processing was investigated by analyzing the amounts of various rRNAs in growing Escherichia coli cells treated with doxycycline. The results showed a doxycycline dose-dependent decrease in mature 16S and 23S rRNAs, concurrent with an accumulation of the initial rRNA transcripts and long precursors. Morphologically, treated cells were elongated at low drug concentrations, while nucleoid degeneration indicative of cell death occurred at higher drug concentrations. These observations suggest that doxycycline inhibits the cleavage and processing of bacterial rRNA transcripts/precursors, leading to impaired formation of mature rRNAs, and the consequent inhibition of protein synthesis for which the tetracycline group of antibiotics are renowned. Since rRNA structure and processing pathway is conserved among bacterial species, this mechanism may account for the broad spectrum of antibiotic activity and selective microbial protein synthesis inhibition of doxycycline and the tetracyclines.

Phenotypic and genotypic drug resistance profile of Salmonella serovars isolated from poultry farm and processing units located in and around Mumbai city, India.

Background and Aim:The extensive use of antimicrobials in poultry has led to an increase in bacterial multidrug resistance, and the emergence of multidrug-resistant nontyphoidal Salmonella is a global problem. This study was performed to detect antibiotic-resistant Salmonella serovars in poultry farming and processing environment.Materials and Methods:A total of 956 various samples, comprising 432 farm origin, 324 poultry processing stage wise and environmental, and 154 product processing stages and environmental samples, were collected from poultry farms and processing units located in and around Mumbai city. Of a total of 71 recovered isolates, 42 randomly selected Salmonella isolates were subjected for antibiotic susceptibility testing by disk diffusion method and serotyping. A total of 31 serotypically confirmed isolates were characterized for the presence of tetA, tetB, blaTEM, and CTX-M gene.Results:Higher resistance was recorded against Doxycycline (100%), followed by Oxytetracycline (97.62%), Neomycin (88.10%), Erythromycin (83.33%), Tetracycline (78.57%), and Ceftizoxime (35.71%). Resistance from 0.00 to 26.19 percent was found to antimicrobials, namely Norfloxacin (26.19%), Ampicillin (21.43%), Azithromycin (21.43%), Ciprofloxacin (19.05%), Colistin (4.76%), Streptomycin (16.67%), Cefotaxime (14.19%), Enrofloxacin (14.29%), Amoxyclav (14.29%), Gentamicin (7.14%), Chloramphenicol (4.76%), Amikacin (4.76%), and Ceftazidime (0.0%). Results demonstrate that the Salmonella Virchow dominated and all serotypes were found to carry Tetracycline resistance gene tetA, 5 isolates were found to be positive for blaTEM, whereas none of the isolates were carrying tetB and CTX-M gene.Conclusion:This study revealed that there is a significant rise of Tetracycline resistance with the presence of tetA gene in Salmonella spp. which indicates selective pressure for adopting resistance against tetracycline group of antibiotics.

Detection of sulfonamide and tetracycline antibiotic residues in Turkish pine honey

ABSTRACTPine honey is a honeydew honey that can be produced endemically in eastern Mediterranean. Turkey is the world’s largest producer of pine honey with around 95% export share. Antibiotic residue in honey is still an important problem worldwide. The aim of this study was to determine sulfonamide and tetracycline group antibiotics in pine honey collected from Aegean Region of Turkey. For this purpose, 59 natural pine honey samples were detected by competitive enzyme-linked immunoassay method. Tetracycline group antibiotics were found in 35 honey samples out of 59 between 6 and 42 ppb, whereas in 24 of the samples the levels were below the detection level (< 4 ppb). Sulfonamide group antibiotics were found in 31 honey samples out of 59 between 3 and 32 ppb, while 28 samples were below the detection limit (< 2 ppb). There are no maximum residue limits established for antibiotics in honey according to the European Community regulations, which means honeys should not contain antibiotics.

Degradation of tetracycline antibiotics by advanced oxidation processes: application of MnO2 nanomaterials

Recently, pharmaceutical and personal care products (PPCPs) have emerged out globally as a new category of harmful contaminant. Tetracycline group of antibiotics (TCs), including tetracycline (TC), oxytetracycline (OTC), tetracycline hydrochloride (TCH) and chlorotetracycline (CTC), is also included in this group. The human health and ecosystem have been affected adversely by TCs. In the last few decades, advanced oxidation processes (AOPs) have come out as one of the most sought out techniques for removing antibiotics from aqueous matrices. Here, we have highlighted and compared the existing MnO2-based degradation methods of TCs. Special reference is made on the application of MnO2 nanosheets as elaborated earlier. The MnO2 is highly porous having very high surface area. Optimization of reaction parameters and the method of TCH degradation is the main focus of the paper. A comparative study of the present method with the existing methods has been done.