A double-stage Lab-In-Syringe automated extraction procedure coupled online to HPLC for the determination of four sulfonamides in urine has been developed. Our method is based on homogeneous liquid-liquid extraction at pH 3 using water-miscible acetonitrile with induction of phase separation by the addition of a saturated solution of kosmotropic salts MgSO4 and NaCl. The procedure allowed extraction of the moderately polar model analytes and the use of a solvent that is compatible with the used separation technique. The automated sample preparation system based on the stirring-assisted Lab-In-Syringe approach was coupled on-line with HPLC-UV for the subsequent separation of the sulfonamide antibiotics. To improve both preconcentration factor and extract cleanup, the analytes were trapped at pH 10 in an anion-exchange resin cartridge integrated into the HPLC injection loop thus achieving a double-stage sample clean-up. Analytes were eluted using an acidic HPLC mobile phase in gradient elution mode. Running the analytes separation and the two-step preparation of the following sample in parallel reduced the total time of analysis to mere 13.5 min. Limits of detection ranged from 5.0 to 7.5 μg/L with linear working ranges of 50-5000 μg/L (r2 > 0.9997) and RSD ≤ 5% (n = 6) at a concentration level of 50 μg/L. Average recovery values were 102.7 ± 7.4% after spiking of urine with sulfonamides at concentrations of 2.5 and 5 mg/L followed by 5 times dilution. To the best of our knowledge, the use of Lab-In-Syringe for the automation of coupled homogeneous liquid-liquid extraction and SPE for preparation of the complex matrices suitable for separation techniques is here presented for the first time.
Tyramine is one of the most toxic biogenic amines and it is produced commonly by lactic acid bacteria in fermented food products. In present study, we investigated the influence of selected nisin-producing Lactococcus lactis subsp. lactis strains and their cell-free supernatants (CFSs) on tyramine production by four Lactobacillus and two Lactiplantibacillus strains isolated from cheese and beer. Firstly, we examined the antimicrobial effect of the CFSs from twelve Lactococcus strains against tested tyramine producers by agar-well diffusion assay. Six Lactococcus strains whose CFSs showed the highest antimicrobial effect on tyramine producers were further studied. Secondly, we investigated the influence of the selected six Lactococcus strains and their respective CFSs on tyramine production by tested Lactobacillus and Lactiplantibacillus strains in MRS broth supplemented with 2 g.L-1 of l-tyrosine. Tyramine production was monitored by HPLC-UV. The tyramine formation of all tested Lactobacillus and Lactiplantibacillus strains was not detected in the presence of Lc. lactis subsp. lactis CCDM 71 and CCDM 702, and their CFSs. Moreover, the remainder of the investigated Lactococcus strains (CCDM 670, CCDM 686, CCDM 689 and CCDM 731) and their CFSs decreased tyramine production significantly (P < 0.05) - even suppressing it completely in some cases - in four of the six tested tyramine producing strains.
- MeSH
- antibakteriální látky analýza metabolismus farmakologie MeSH
- kultivační média chemie metabolismus farmakologie MeSH
- Lactobacillaceae účinky léků růst a vývoj izolace a purifikace MeSH
- Lactobacillus účinky léků růst a vývoj izolace a purifikace MeSH
- Lactococcus lactis chemie metabolismus MeSH
- pivo mikrobiologie MeSH
- sýr mikrobiologie MeSH
- tyramin analýza metabolismus farmakologie MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- Publikační typ
- časopisecké články MeSH
Fytochemická analýza methanolického extraktu Helichrysum petiolare Hilliard & B. L. (Asteraceae) prokázala přítomnost sekundárních metabolitů patřících mezi fenylpropanoidy a flavonoidy. Pomocí preparativní HPLC se podařilo vyizolovat pět obsahových látek: kumarin skopolin (1), kyselinu 3-chlorogenovou (2), glukosidicky vázaný derivát kyseliny kávové (3), kyselinu dikafeoylchinovou (5) a flavonoid isokvercitrin (4). V druhu H. petiolare byly tyto sloučeniny identifikovány poprvé. Při testování antibakteriální aktivity bylo zjištěno, že pouze kyselina dikafeoylchinová vykazuje mírnou antibakteriální aktivitu proti Escherichia coli CCM 7929 v koncentraci 512 μg ∙ ml–1.
The phytochemical analysis of a methanolic extract from Helichrysum petiolare Hilliard & B. L. (Asteraceae) confirmed the content of phenylpropanoids and flavonoids. Five secondary metabolites were isolated using preparative HPLC, namely coumarin scopolin (1), 3-chlorogenic acid (2), caffeic acid-hexose derivative (3), dicaffeoylquinic acid (5), and the flavonoid isoquercitrin (4). These compounds were identified from this species for the first time. Only dicaffeoylquinic acid was able to inhibit Escherichia coli CCM 7929 at the concertation of 512 μg ∙ mL–1 in a screening of antibacterial activity.
Vancomycin is often used in orthopedic surgery as a local prophylaxis of bacterial infection. The aim of this work was to compare the release of vancomycin and its biologically inactive crystalline degradation products (CDP-1) during in vitro experiments from different types of local antibiotic delivery systems (bone grafts and bone cements). The concentrations of vancomycin and its crystalline degradation products were determined by high-performance liquid chromatography. Each experiment was performed in a phosphate buffer solution over 21 days. Morselized bone grafts, synthetic bone cements Palacos and Copal, and synthetic bone grafts were tested as local carriers of vancomycin. The highest concentration approximately 670 mg/L of vancomycin was released from synthetic bone grafts Actifuse. Even after 21 days, the concentration of vancomycin was still above the minimum inhibitory concentration (MIC). The maximum concentration of vancomycin released in two experiments with human bone grafts exceeded 600 mg/L during the first day and was still above MIC level 21 days later when the experiment was concluded. By comparing the synthetic bone cements Palacos and Copal, Copal had the average maximum concentration of only 32.4 mg/L and Palacos 35.7 mg/L. The concentration of vancomycin fell below the MIC for vancomycin-resistant Staphylococcus aureus (VRSA) on the seventh day with Palacos and the ninth day with Copal. This study showed the insufficient concentration of released vancomycin from synthetic bone cements at the end of the experiment. For improvement of local prophylaxis, it would be beneficial to increase the amount of vancomycin in bone cements.
- MeSH
- antibakteriální látky analýza metabolismus MeSH
- kostní cementy analýza MeSH
- lidé MeSH
- methicilin rezistentní Staphylococcus aureus účinky léků MeSH
- mikrobiální testy citlivosti MeSH
- transplantace kostí MeSH
- vankomycin analýza metabolismus MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The residual antibiotics in the environment have lately caused widespread concerns. However, little information is available on the antibiotic bioaccumulation and its health risk in drinking water resources of South China. Therefore, the occurrence, distribution, and health risk of four quinolone antibiotics including ofloxacin (OFX), norfloxacin (NOR), ciprofloxacin (CIP), and enrofloxacin (ENR) in the Qingshitan reservoir using high-performance liquid chromatography were investigated. Results revealed that the concentrations in water, sediment, and edible fish ranged from 3.49-660.13 ng/L, 1.03-722.18 μg/kg, and 6.73-968.66 μg/kg, respectively. The ecological risk assessment via the risk quotient (RQ) method showed that the values in sediment were all greater than 1, posing a high risk to the environment. The health risk index of water samples was at the maximum acceptable level, with OFX at the top while the rest were at the medium risk level. The main edible fish kinds of the reservoir had high dietary safety and the highest contaminations were found in carnivorous feeding habits and demersal habitat fishes with OFX as the highest magnitude. Source identification and correlation analysis using SPSS showed significant relationships between NOR with pH and turbidity (in water), as well as total phosphor (TP) and total organic carbon (TOC) in sediment. NOR was the highest in sediment which mostly sourced from livestock wastewater, croplands irrigation drain water, and stormwater. Correlations between CIP and ENR with TP were significant, while OFX was positively associated with total nitrogen (TN) which mainly originated from urban sewage as well as directly dosed drugs in fish farms. In conclusion, our results are of great significance for ensuring the safety of drinking water and aquatic products in this region.
- MeSH
- antibakteriální látky škodlivé účinky analýza MeSH
- chemické látky znečišťující vodu škodlivé účinky analýza MeSH
- chinolony škodlivé účinky analýza MeSH
- geologické sedimenty chemie MeSH
- hodnocení rizik * MeSH
- monitorování životního prostředí * MeSH
- řeky chemie MeSH
- řízení kvality MeSH
- ryby * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Čína MeSH
- MeSH
- antibakteriální látky * analýza aplikace a dávkování terapeutické užití MeSH
- antibiotická rezistence MeSH
- gonorea * farmakoterapie mikrobiologie patologie MeSH
- klinické zkoušky jako téma MeSH
- lidé MeSH
- mikrobiální testy citlivosti * MeSH
- Neisseria gonorrhoeae izolace a purifikace patogenita MeSH
- Check Tag
- lidé MeSH
In recent years, antibiotics have been used for human and animal disease treatment, growth promotion, and prophylaxis, and their consumption is rising worldwide. Antibiotics are often not fully metabolized by the body and are released into the aquatic environment, where they may have negative effects on the non-target species. This review examines the recent researches on eight representative antibiotics (erythromycin, trimethoprim, sulfamethoxazole, tetracycline, oxytetracycline, ofloxacin, ciprofloxacin, and amoxicillin). A detailed overview of their concentrations in surface waters, groundwater, and effluents is provided, supported by recent global human consumption and veterinary use data. Furthermore, we review the ecotoxicity of these antibiotics towards different groups of organisms, and assessment of the environmental risks to aquatic organisms. This review discusses and compares the suitability of currently used ecotoxicological bioassays, and identifies the knowledge gaps and future challenges. The risk data indicate that selected antibiotics may pose a threat to aquatic environments. Cyanobacteria were the most sensitive organisms when using standard ecotoxicological bioassays. Further studies on their chronic effects to aquatic organisms and the toxicity of antibiotic mixtures are necessary to fully understand the hazards these antibiotics present.
- MeSH
- amoxicilin MeSH
- antibakteriální látky analýza toxicita MeSH
- chemické látky znečišťující vodu analýza toxicita MeSH
- ciprofloxacin MeSH
- ekotoxikologie MeSH
- erythromycin MeSH
- hodnocení rizik MeSH
- monitorování životního prostředí * MeSH
- podzemní voda MeSH
- sulfamethoxazol MeSH
- tetracyklin MeSH
- trimethoprim analýza MeSH
- vodní organismy MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Over the last two decades, the group of techniques called affinity probe CE has been widely used for the detection and the determination of several types of biomolecules with high sensitivity. These techniques combine the low sample consumption and high separation power of CE with the selectivity of the probe to the target molecule. The assays can be defined according to the type of probe used: CE immunoassays, with an antibody as the probe, or aptamer-based CE, with an aptamer as the probe. Immunoassays are generally divided into homogeneous and heterogeneous groups, and homogeneous variant can be further performed in competitive or noncompetitive formats. Interacting partners are free in solution at homogeneous assay, as opposed to heterogeneous analyses, where one of them is immobilized onto a solid support. Highly sensitive fluorescence, chemiluminescence or electrochemical detections were typically used in this type of study. The use of the aptamers as probes has several advantages over antibodies such as shorter generation time, higher thermal stability, lower price, and lower variability. The aptamer-based CE technique was in practice utilized for the determination of proteins in biological fluids and environmentally or clinically important small molecules. Both techniques were also transferred to microchip. This review is focused on theoretical principles of these techniques and a summary of their applications in research.
Environmental pollutants, including antibiotics (ATBs), have become an increasingly common health hazard in the last several decades. Overdose and abuse of ATBs led to the emergence of antibiotic-resistant genes (ARGs), which represent a serious health threat. Moreover, water bodies and reservoirs are places where a wide range of bacterial species with ARGs originate, owing to the strong selective pressure from presence of ATB residues. In this regard, graphene oxide (GO) has been utilised in several fields including remediation of the environment. In this review, we present a brief overview of resistant genes of frequently used ATBs, their occurrence in the environment and their behaviour. Further, we discussed the factors influencing the binding of nucleic acids and the response of ARGs to GO, including the presence of salts in the water environment or water pH, because of intrinsic properties of GO of not only binding to nucleic acids but also catalysing their decomposition. This would be helpful in designing new types of water treatment facilities.
Adsorption characteristics of high-silica zeolites (HSZSM-5) for two selected sulfonamide antibiotics (SAs) (sulfamethoxazole and sulfadiazine) were investigated. The SAs were almost completely (>90%) removed from the water by HSZSM-5. Adsorption followed second-order kinetics with liquid-film diffusion as the dominant mechanism. SA adsorption capacity on high-silica zeolites was examined in terms of pH, temperature, and the presence of natural organic matter (NOM). HSZSM-5 had better adsorption performance in acidic conditions, and the apparent distribution coefficient indicated that SA0 species were the major contribution to the overall adsorption at pH of 2-10. Adsorption of SAs on HSZSM-5 was a spontaneous and exothermic physisorption process. SA removal by HSZSM-5 was a mixed mechanism through ion-exchange and hydrophobic interaction. HSZSM-5 has potential application prospects in removing SAs from wastewater.