Toxicity Of Ciprofloxacin Research Articles

N, P co-doped graphite felt cathode for efficient removal of ciprofloxacin in an ascorbic acid-coupled electro-Fenton process: Simultaneously enhancing H2O2 generation and Fe3+/Fe2+ cycling.

To enhance the contaminant removal efficiency of the electro-Fenton (E-Fenton) process, a nitrogen and phosphorus co-doped graphite felt (NPGF) cathode was synthesized using an anodic oxidation technique. An ascorbic acid-coupled NPGF E-Fenton system was then established for the degradation of ciprofloxacin (CIP). The NPGF cathode featured abundant oxygen-containing functional groups (such as -COOH and -OH), which enhanced the selectivity of oxygen reduction and facilitated the formation of H2O2. The introduction of N and P doping disrupted the charge balance within the carbon framework, accelerating electron transfer. Together, the NPGF electrode and ascorbic acid enhanced the cycling of Fe3+/Fe2+ while preventing the formation of iron sludge. Under optimal conditions (ascorbic acid concentration of 0.3 mM, current density of 2.0 mA cm-2, pH of 3.0, aeration rate of 0.6 L min-1, and Fe2+ concentration of 0.2 mM), CIP was completely removed within 20 min. The NPGF electrode exhibited excellent stability, maintaining 95.35% CIP removal even after 8 cycles. Analysis revealed that singlet oxygen primarily mediated the degradation of CIP, with its concentration measured at 1.23 × 10-7 M. Density functional theory was used to analyze the characteristics and potential attack sites of CIP, enabling the proposal of plausible degradation pathways. Toxicity simulations and Escherichia coli growth inhibition experiments demonstrated a reduction in the toxicity of CIP and its intermediate products. This study offers a valuable reference for improving the efficiency of E-Fenton technology in antibiotic wastewater treatment.

Co-occurrence of cadmium and ciprofloxacin in environmental media decreases ciprofloxacin degradation by biogenic manganese oxides.

The coexistence of antibiotics with heavy metals is detrimental to humans and the environment. In urban water environments, Cadmium (Cd) and ciprofloxacin (CIP) frequently co-occur. Biogenic manganese oxides (BMOs) are a promising environmental bioremediation material due to their remarkable adsorption and oxidation properties. However, BMOs' removal mechanism in an environment where Cd and CIP co-occur is not yet unknown. We identified a manganese (Mn)-oxidising bacterium, Bacillus sp. XM02, with a strong ability for Mn (II) oxidation (85.23%) and BMOs production, and investigated its competitive removal mechanism in an environment with Cd and CIP co-occurrence. The BMOs exhibited a glorious CIP degradation ability and led to a marked decrease in the toxicity of CIP following oxidative degradation in Escherichia coli experiments. In contrast, in the co-existence of Cd and CIP, Cd hindered CIP removal by BMOs, but CIP did not affect Cd removal. Kinetic experiments combined with XPS characterisation revealed that the k value of Cd (297.39 h-1) was much higher than that of CIP (5.53 h-1), demonstrating that Cd was immediately adsorbed onto the surface of BMOs through a Cd-O bond. The surface potentials of BMOs carrying Cd alone and both Cd and CIP on the surface were similar, revealing that the electronegativity of Cd-carrying BMOs was greatly weakened (from -34.8 mV to -21 mV/-23 mV), which further reduced the BMOs' electrostatic interaction with CIP. Moreover, the concentration of dissolved Mn (III) in the co-existence group was lower than that in the CIP alone, indicating that the presence of Cd reduced the transformation of Mn (IV) to Mn (III) by BMOs. Consequently, Cd attenuated the effect of active Mn (IV) sites of BMOs on CIP's piperazine ring oxidative degradation. These results offer a theoretical direction for the use of BMOs to reduce the risk posed by antibiotics and heavy metals pollution in co-occurrence environments.

Efficient degradation of ciprofloxacin by peroxymonosulfate activated with Co-loaded waste biomass: Efficiency, stability, and mechanism

Waste-derived biochar (BC) loaded with transition metals holds promising potential for remediation of wastewater, owing to the high efficiency and minimal risk of metal leaching. Herein, gold passion fruit shell (PFS) derived biochar loaded with cobalt (Co-PFSBC) was synthesized for removal of ciprofloxacin (CIP) from water by activating peroxymonosulfate (PMS). Both the pyrolysis temperature and the Co doping load significantly influence the physicochemical property of Co-PFSBC, thereby affecting the removal efficiency of CIP. 98.51 % of CIP (10 mg/L) is removed within 120 min under the optimal conditions with 100 mg/L of 4 %Co-PFSBC-400 and 1.5 mM of PMS. In addition, 4 %Co-PFSBC-400 shows excellent catalytic performance for a wide range of refractory organics. Based on the quenching experiment and electron paramagnetic resonance (EPR), both radical and non-radical process (singlet oxygen, 1O2) are involved in the 4 %Co-PFSBC-400/PMS system. The total concentration (2.44 mM) of 1O2 generated in the first 30 min reaction indicates that 1O2 plays a major contribution in the CIP degradation. Moreover, the toxicity of CIP and its degradation intermediates were calculated and a plausible mineralization pathway is proposed according to the intermediates.

Microwave-assisted PMS activation Ti3C2/LaFe0.5Cu0.5O3-P catalysts for efficient degradation of CIP: Enhancement of catalytic performance by phosphoric acid etching

The LaFe0.5Cu0.5O3 perovskite synthesised by MOFs template method was compounded with Mxene Ti3C2, and the novel catalyst M-Ti3C2/LFCO-P was subsequently prepared by phosphoric acid etching. This catalyst effectively induced microwave activation of peroxymonosulfate (PMS), and ciprofloxacin (CIP) was efficiently degraded with a degradation rate reaching 95.48 % within 14 min. Characterization results revealed that the MOFs template method and phosphoric acid etching increased specific surface area (from 25.91 m2/g to 142.41 m2/g) of catalyst and improved its pore size distribution. Phosphoric acid etching successfully introduced phosphorus functional groups and promoted the formation of more oxygen vacancies, thereby significantly enhancing the catalytic activity of the catalyst. The conversion of free radicals and the transformation of free radicals to non-free radicals were demonstrated. Additionally, the catalyst exhibited higher electron transfer efficiency. The catalytic reaction was primarily driven by O2– and 1O2, with OH, SO4−, and e- playing auxiliary roles. Furthermore, the degradation pathway and toxicity of CIP were also evaluated. This work provides a new perspective for improving the catalytic degradation activity of antibiotics by perovskite catalysts.

Effects of Enrofloxacin and Ciprofloxacin on Growth and Toxin Production of Microcystis aeruginosa

Microcystis aeruginosa is a common cyanobacterium found in water blooms and often causes ecological harm. Antibiotics are also increasingly used for the prevention and treatment of bacterial infections in aquaculture. However, since most antibiotics cannot be fully metabolized, they enter the water environment and cause ecological impacts. In this paper, the effects of the two fluoroquinolone antibiotics (enrofloxacin and ciprofloxacin) on the population density and microcystins (MCs) production of M. aeruginosa were studied. It is of great significance for the ecological risk assessment of antibiotics in the water environment. The results showed that the 96h EC50 values of enrofloxacin and ciprofloxacin to M. aeruginosa were 56.10 mg/L and 49.80 mg/L, respectively, and the toxicity of ciprofloxacin to M. aeruginosa was slightly stronger than that of enrofloxacin. With the increase in the two antibiotic concentration, the growth inhibition rate (IR) increased, but when the concentration reached a certain level, the IR would reach its threshold. Long-term exposure to low concentrations of these two antibiotics is not only more likely to lead to the outbreak of M. aeruginosa, but also increase its toxin production capacity. The highest contents of MCs in enrofloxacin and ciprofloxacin groups were 95.539 μg/g and 93.720 μg/g, respectively. The MCs value of these three enrofloxacin treatment groups was more than above 51.8 times that of control group (CK) on the 4th day; from 8th day to 14th day, the MCs value of these three enrofloxacin treatment groups was more than above 3.2 times that of CK group. For ciprofloxacin, the MCs value of the treatment group was more than 64.98 times that of the CK group on the 4th day, and from 8th day to 14th day, the MCs value of the treatment group was more than 2.7 times that of the CK group. These findings provide crucial management rationale.

Elucidation of mechanisms, pathways, and toxicity of fabricated Z-scheme KNbO3/ZnIn2S4 hollow core–shell composites for enhanced ciprofloxacin photodegradation

Semiconductor photocatalysis technology for environmental remediation faces primary challenges, such as charge-carrier recombination and interfacial charge transfer inhibition, which affect its degradation efficiency in removing organic contaminants. In this work, we successfully synthesized a unique Z-scheme KNbO3/ZnIn2S4 hollow core–shell microsphere via a combined hard template, thermal treatment, and hydrothermal processes as the photocatalyst for ciprofloxacin (CIP), oxytetracycline hydrochloride (OTCH), and rhodamine B (RhB) remediation under sunlight irradiation. Compared to the pure KNbO3 and ZnIn2S4, our optimized 15-KNbO3/ZnIn2S4 composite exhibited enhanced photodegradation performance with up to 99.8 %, 96.8 % and 97.5 % for CIP, OTCH, and RhB removal within 110 min, respectively. At the KNbO3/ZnIn2S4 heterojunction interface, the composite developed its internal electric field and enhanced its photoabsorption under visible light region, thus boosting its charge separation. Subsequently, we evaluate the removal of total organic carbon (TOC) concentration and the influence of different ions on CIP degradation. In addition, we systematically investigated the Z-scheme charge migration process within the heterojunction with a series of experiments. Our results indicated that the hydroxyl and superoxide radicals were the dominant active species during photocatalysis. The composite also could achieve excellent stability and adaptability. We also managed to identify the CIP-degraded intermediates and deduce their possible degradation pathways. Lastly, our toxicity analysis revealed that CIP toxicity could decrease gradually during photocatalysis. In this work, we presented a unique method for preparing inexpensive and highly efficient Z-scheme hollow core–shell structure photocatalysts with excellent antibiotic remediation in water under simulated sunlight illumination.

Toxicity of ciprofloxacin and ofloxacin to Moina macrocopa and investigation of p-value adjustments for (eco)toxicological studies

Ciprofloxacin (CFX) and ofloxacin (OFX) are commonly found as residual contaminants in aquatic environments, posing potential risks to various species. To ensure the safety of aquatic wildlife, it is essential to determine the toxicity of these antibiotics and establish appropriate concentration limits. Additionally, in (eco)toxicological studies, addressing the issue of multiple hypothesis testing through p-value adjustments is crucial for robust decision-making. In this study, we assessed the no observed adverse effect concentration (NOAEC) of CFX and OFX on Moina macrocopa across a concentration range of 0–400 µg L−1. Furthermore, we investigated multiple p-value adjustments to determine the NOAECs. Our analysis yielded consistent results across seven different p-value adjustments, indicating NOAECs of 100 µg CFX L−1 for age at first reproduction and 200 µg CFX L−1 for fertility. For OFX treatment, a NOAEC of 400 µg L−1 was observed for both biomarkers. However, further investigation is required to establish the NOAEC of OFX at higher concentrations with greater certainty. Our findings demonstrate that CFX exhibits higher toxicity compared to OFX, consistent with previous research. Moreover, this study highlights the differential performance of p-value adjustment methods in terms of maintaining statistical power while controlling the multiplicity problem, and their practical applicability. The study emphasizes the low NOAECs for these antibiotics in the zooplanktonic group, highlighting their significant risks to ecological and environmental safety. Additionally, our investigation of p-value adjustment approaches contributes to a deeper understanding of their performance characteristics, enabling (eco)toxicologists to select appropriate methods based on their specific needs and priorities.

Water brownness regulates the bioavailability of a fluoroquinolone antibiotic: UV-absorbance as a predictor of ciprofloxacin ecotoxicity

Dissolved organic carbon (DOC) is a powerful regulator of the ecotoxicity of ciprofloxacin (CIP), a widely applied fluoroquinolone antibiotic. In this study, we investigated the impact of DOC from a variety of sources on CIP bioavailability, using a cyanobacteria growth inhibition test with Microcystis aeruginosa. We analyzed the impact from two perspectives: (1) DOC concentration, and (2) water brownness, defined in this work as the light absorbance of DOC solutions. The toxicity tests were conducted with (1) unprocessed freshwater DOC in the naturally occurring state, (2) DOC extracted from a freshwater stream (Schwarzbach stream, Küchelscheid, Belgium), and (3) the commercial DOC product Suwannee River organic matter. Across all DOC sources investigated, a strong negative correlation was observed between CIP ecotoxicity and light absorbance at four wavelengths across the ultraviolet–visible range (e.g., A350), whereas CIP ecotoxicity correlated poorly with the DOC concentration. In addition, the interactions between CIP and DOC were modelled as a CIP-DOC binding process to allow the quantification of the inhibitory effects of DOC on CIP toxicity via binding constants (Kd,CIPx, with x being the ionic charge + or +/−, L g−1). Processed DOC sources showed higher binding potency than most of the unprocessed DOC sources, suggesting that toxicity tests employing only processed DOC potentially overestimates the impact of DOC in natural environments. Nonetheless, the light absorption coefficient (i.e., ε350) appeared a reliable predictor of the Kd,CIP+/− (and thus of the potential of the DOC source to reduce ecotoxicity of CIP) of both processed and unprocessed DOC. The relationship can be further incorporated into model simulations to estimate CIP bioavailability in dynamic environments. It is concluded that the brownness of water is a better predictor of the impact of DOC on CIP bioavailability than the DOC concentration itself.

The Use of Aquatic Macrophytes as a Nature-Based Solution to Prevent Ciprofloxacin Deleterious Effects on Microalgae

Macrophytes have demonstrated excellent potential for the removal of pharmaceuticals from water. However, there is a lack of studies on the ecotoxicity of water after phytoremediation. In this study, we evaluated the toxicity of ciprofloxacin (Cipro) on the microalgae cells of Desmodesmus subspicatus exposed to water contaminated with Cipro and previously treated by Salvinia molesta or Egeria densa for 96 h. Microalgae exposed to Cipro (1, 10, and 100 µg L−1) in untreated water showed decreased rates of growth, respiration, and photosynthesis, and increased oxidative status (hydrogen peroxide concentration) and oxidative damages (lipid peroxidation). S. molesta exhibited a greater phytoremediation capacity than E. densa, reducing Cipro concentrations in water to below its toxic threshold to D. subspicatus (2.44 µg L−1), even when the antimicrobial was present at a concentration of 10 µg L−1. During the water treatment, neither S. molesta nor E. densa released compounds that had a toxic effect on D. subspicatus. This work demonstrates the novelty of using S. molesta and E. densa as a nature-based solution to remove Cipro from contaminated water. For the first time, we provide evidence of the ecotoxicological safety of this approach, as it prevents the deleterious effects of Cipro on photosynthetic microorganisms and helps to avoid the development of antimicrobial resistance.

Hierarchically-structured laccase@Ni3(PO4)2 hybrid nanoflowers for antibiotic degradation: Application in real wastewater effluent and toxicity evaluation

Laccase@Ni3(PO4)2 hybrid nanoflowers (HNFs) were prepared by the anisotropic growth of biomineralized nickel phosphate. The immobilization yield was 77.5 ± 3.6 %, and the immobilized enzyme retained 50 % of its initial activity after 18 reusability cycles. The immobilized and free enzymes lost 80 % of their activity after 18 and 6 h incubation in municipal wastewater effluent (MWWE), respectively. The increase in α-helix content (8 %) following immobilization led to a more rigid enzyme structure, potentially contributing to its improved stability. The removal of ciprofloxacin from MWWE by laccase@Ni3(PO4)2·HNFs/p-coumaric acid oxidation system was optimized using a Box-Behnken design. Under the optimized conditions [initial laccase activity (0.05 U mL−1), the concentration of p-coumaric acid (2.9 mM), and treatment time (4.9 h)], the biocatalyst removed 90 % of ciprofloxacin (10 mg L−1) from MWWE. The toxicity of ciprofloxacin against some G+ and G− bacteria was reduced by 35–70 %, depending on their strain. The EC50 of ciprofloxacin for the alga Raphidocelis subcapitata reduced from 3.08 to 1.07 mg L−1 (p-value <0.05) after the bioremoval. Also, the acute and chronic toxicity of identified biodegradation products was lower than ciprofloxacin at three trophic levels, as predicted by ECOSAR software.

Direct toxicity of six antibiotics on soil bacterial communities affected by the addition of bio-adsorbents

Reducing the toxicity caused by antibiotics on bacterial communities in the soil is one of the great challenges of this century. For this, the effectiveness of amending the soil with different bioadsorbents such as crushed mussel shell (CMS), pine bark (PB) and biomass ash (BA), as well as combinations of them (CMS + PB and PB + BA) was studied at different doses (0 g kg−1 to 48 g kg−1). Soil samples were spiked, separately, with increasing doses (0–2000 mg kg−1) of cefuroxime (CMX), amoxicillin (AMX), clarithromycin (CLA), azithromycin (AZI), ciprofloxacin (CIP) and trimethoprim (TMP). Their toxicity on bacterial growth was estimated using the tritium-labeled leucine (3H) incorporation method. Toxicity was observed to behave differently depending on the antibiotic family and bioadsorbent, although in different magnitude and at different doses. The toxicity of β-lactams (AMX and CXM) was reduced by up to 54% when the highest doses of bio-adsorbents were added due to the increase in pH (CMS and BA) and carbon (PB) contribution. Macrolides (CLA and AZI) showed slight toxicity in un-amended soil samples, which increased by up to 65% with the addition of the bio-adsorbents. The toxicity of CIP (a fluoroquinolone) increased with the dose of the bio-adsorbents, reaching up to 20% compared with the control. Finally, the toxicity of TMP (a diaminopyrimidine) slightly increased with the dose of bio-adsorbents. The by-products that increase soil pH are those that showed the highest increases of CLA, AZI, CIP and TMP toxicities. These results could help to prevent/reduce environmental pollution caused by different kinds of antibiotics, selecting the most appropriated bio-adsorbents and doses.

Ciprofloxacin properties, impacts, and remediation

Abstract The discovery of antibiotics has led to a major development in providing treatment for different types of bacterial infections. Among the numerous types of antimicrobial agents used, fluoroquinolones have shown potential activity against various harmful pathogens, which cause various kinds of infections pertaining to skin, urinary tract, respiratory tract, gastrointestinal tract as well as sexually transmitted diseases (STDs). Among all classes of fluoroquinolones, ciprofloxacin is the most used and shows broad-spectrum activity against both gram-positive and gram-negative bacteria. The pharmacokinetic profile is higher in comparison with other antibiotics. It inhibits DNA replication and transcription. Although the use of ciprofloxacin has helped in decreasing the death rate, its increased usage has caused escalated contamination in soil and water. This has severely affected humans, plants, animals, and microbes. As ciprofloxacin does not immediately biodegrade, therefore, it can easily be found in soil and water sources. The toxicity of ciprofloxacin causes the development of resistance and the generation of reactive oxygen species and oxidative stress among living organisms. It also impacts the reproductive system of fishes and amphibians and plant physiology. In order to remediate the antibiotics from the environment a recent technique, phytoremediation has attracted researchers, which may provide a method for the removal of antibiotics. The present review focuses on the physical and pharmacokinetics properties of ciprofloxacin, its action mechanism, its toxicological effects, effect on microbial community, and various other living organisms along with a discussion of remediation of ciprofloxacin.

Protective effect of cinnamon oil against ciprofloxacin toxicity on liver and kidney of male Wistar rats

Cinnamon zeylanicum is one of many herbal medications. This herb contains different materials like, cumarin, cinnamaldehyde and cinnamic acid. The plant plays a role as antiallergic, antiviral, antimicrobial, anti-inflammatory and antioxidant and other health conditions. This study focused on the therapeutic effect of cinnamon oil on hepatorenal toxicity induced by ciprofloxacin in male rats. Forty rats were housed in the animal house of the College of Pharmacy, University of Kerbala, Karbala city, Iraq. The animals were separated into four groups: Group 1. Control group (not taken drug nor cinnamon oil), Group 2. Ciprofloxacin group (drenched 250 mg/kg/day of ciprofloxacin for 30 days), Group 3. Cinnamon oil group (drenched 1ml/kg/day of cinnamon oil for 30 days) and Group 4. Cinnamon+ciprofloxacin group (drenched 1ml/kg/day of cinnamon + 250 mg/kg/day of ciprofloxacin for 30 days). Finally, 2ml of blood was collected from each rat and the serum was separated for estimating the biochemical parameters of the liver like, Aspartate transaminase (AST), alanine transaminase(ALT) and alkaline phosphatase(ALP) and the kidney (Creatinine, Urea and albumin) . The results proved that ciprofloxacin significantly elevates the parameters of the liver and kidney (p≤0.05). The results also proved the benefit of cinnamon oil in improving health by reducing the toxic effect of ciprofloxacin by lowering the elevated levels of (liver enzymes, creatinine, urea and albumin). The study showed that this oil reduced the toxic effect of ciprofloxacin on the kidney and liver.

Chitosan-Based Ciprofloxacin Extended Release Systems: Combined Synthetic and Pharmacological (In Vitro and In Vivo) Studies.

Ciprofloxacin is one of the most effective antibiotics, but it is characterized by a range of side effects. Elaboration of drug-releasing systems which allow to diminish toxicity of ciprofloxacin is a challenging task in medicinal chemistry. The current study is focused on development of new ciprofloxacin releasing systems (CRS). We found that ultrasound efficiently promotes N,N'-dicyclohexyl carbodiimide-mediated coupling between COOH and NH2 functionalities in water. This was used for conjugation of ciprofloxacin to chitosan. The obtained ciprofloxacin/chitosan conjugates are capable of forming their self-assembled nanoparticles (SANPs) in aqueous medium. The SANPs can be additionally loaded by ciprofloxacin to form new CRS. The CRS demonstrated high loading and encapsulation efficiency and they are characterized by extended release profile (20 h). The elaborated CRS were tested in vivo in rats. The in vivo antibacterial effect of the CRS exceeded that of the starting ciprofloxacin. Moreover, the in vivo acute and subacute toxicity of the nanoparticles was almost identical to that of the chitosan, which is considered as the non-toxic biopolymer.

Microplastics and co-pollutant with ciprofloxacin affect interactions between free-floating macrophytes

Microplastic and antibiotic contamination are considered an increasing environmental problem in aquatic systems, while little is known about the impact of microplastics and co-pollutant with antibiotics on freshwater vascular plants, particularly the effects of interactions between macrophytes. Here, we performed a mesocosm experiment to evaluate the impact of polyethylene-microplastics and their co-pollutants with ciprofloxacin on the growth and physiological characteristics of Spirodela polyrhiza and Lemna minor and the interactions between these two macrophytes. Our results showed that microplastics alone cannot significantly influence fresh weight and specific leaf area of the two test free-floating macrophytes, but the effects on photosynthetic pigments, malondialdehyde, catalase and soluble sugar contents were species-specific. Ciprofloxacin can significant adverse effects on the growth and physiological traits of the two test macrophytes and microplastic mitigated the toxicity of ciprofloxacin on the two free-floating plants to a certain extent. In addition, our studies showed that microplastics and co-pollutants can influence relative yield and competitiveness of S. polyrhiza and L. minor by directly or indirectly influencing their physiology and growth. Therefore our findings suggest that species-specific sensibility to microplastic and its co-pollutant among free-floating macrophytes may influence macrophyte population dynamics and thereby community structure and ecosystem functioning. And microplastics altered other contaminant behaviours and toxicity, and may directly or indirectly influence macrophytes interactions and community structure. The present study is the first experimental study exploring the effects of microplastics alone and with their co-pollutants on interactions between free-floating macrophytes, which can provide basic theoretical guidance for improving the stability of freshwater ecosystems.

Unraveling the Toxicity Associated with Ciprofloxacin Biodegradation in Biological Wastewater Treatment.

Incomplete mineralization of antibiotics in biological sludge systems poses a risk to the environment. In this study, the toxicity associated with ciprofloxacin (CIP) biodegradation in activated sludge (AS), anaerobic methanogenic sludge (AnMS), and sulfur-mediated sludge (SmS) systems was examined via long-term bioreactor tests and a series of bioassays. The AS and AnMS systems were susceptible to CIP and its biotransformation products (TPs) and exhibited performance deterioration, while the SmS system exhibited high tolerance against the toxicity of CIP and its TPs along with excellent pollutant removal. Up to 14 TPs were formed via piperazinyl substituent cleavage, defluorination, decarboxylation, acetylation, and hydroxylation reactions in AS, AnMS, and SmS systems. Biodegradation of CIP in the AS, AnMS, and SmS systems, however, could not completely eliminate its toxicity as evident from the inhibition of Vibrio fischeri luminescence along with Escherichia coli K12 and Bacillus subtilis growth. The anaerobic systems (AnMS and SmS) were more effective than the aerobic AS system at CIP biodegradation, significantly reducing the antibacterial activity of CIP and its TPs in the aqueous phase. In addition, the quantitative structure-activity relationship analysis indicated that the TPs produced via decarboxylation and hydroxylation (TP2 and TP4) as well as by cleavage of piperazine (TP12, TP13, and TP14) exhibited higher toxicity than CIP. The findings of this study provide insights into the toxicity and possible risks associated with CIP biodegradation in biological wastewater treatment.

Peroxydisulfate activation by nano zero-valent iron graphitized carbon materials for ciprofloxacin removal: Effects and mechanism

Since the discovery of the potential hazards of ciprofloxacin (CIP) to the ecosystem and human health, there has been an urgent need to develop effective technologies to solve the severe issue. In this work, the nanozero-valent iron graphitized carbon matrix (xFe@CS-Tm) were prepared via a hydrothermal method to activate peroxydisulfate (PDS) for degradation of CIP. Specifically, 0.5Fe@CS-T7 exhibited the excellent catalytic performance for PDS activation to degrade CIP. Moreover, the catalyst exhibited vigorous interference resistance at various pH values, in the presence of various inorganic anions and under humic acid conditions. The characterization results demonstrated that Fe was successfully embedded on the carbon matrix and became the active sites to promote ROS production. It is demonstrated that O2•− was the main active species rather than •OH and SO4•−, based on quench trapping, EPR experiments and steady state concentrations calculations. The possible pathways of CIP degradation were proposed using LC–MS results and density functional theory. The outcomes of the toxicity estimation software tool found that the toxicity of CIP was reduced. This study not only investigated a novel methodology for the degradation of antibiotic wastewater but also provides a feasible pathway for carbon-neutral wastewater treatment.

Boosting antibiotics performance by new formulations with deep eutectic solvents

The critical scenario of antimicrobial resistance to antibiotics highlights the need for improved therapeutics and/or formulations. Herein, we demonstrate that deep eutectic solvents (DES) formulations are very promising to remarkably improve the solubility, stability and therapeutic efficacy of antibiotics, such as ciprofloxacin. DES aqueous solutions enhance the solubility of ciprofloxacin up to 430-fold while extending the antibiotic stability. The developed formulations can improve, by 2 to 4-fold, the susceptibility of Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus) bacteria to the antibiotic. They also improve the therapeutic efficacy at concentrations where bacteria present resistance, without promoting tolerance development to ciprofloxacin. Furthermore, the incorporation of DES decreases the toxicity of ciprofloxacin towards immortalized human epidermal keratinocytes (HaCat cells). The results herein reveal the pioneering use of DES in fluoroquinolone-based formulations and their impact on the antibiotic’s characteristics and on its therapeutic action.

Low concentrations of ciprofloxacin alone and in combination with paracetamol induce oxidative stress, upregulation of apoptotic-related genes, histological alterations in the liver, and genotoxicity in Danio rerio

Nowadays, there are countless articles about the harmful effects of paracetamol (PCM) in non-target organisms. Nonetheless, information regarding the toxicity of ciprofloxacin (CPX) and the CPX-PCM mixture is still limited. Herein, we aimed to evaluate the hepatotoxic and genotoxic effects that ciprofloxacin alone and in combination with paracetamol may induce in Danio rerio adults. For this purpose, we exposed several D. rerio adults to three environmentally relevant concentrations of PCM (0.125, 0.250, and 0.500 μg/L), CPX (0.250, 0.500, and 1 μg/L), and their mixture (0.125 + 0.250, 0.250 + 0.500, and 0.500 + 1 μg/L) for 96 h. The blood samples showed CPX alone and in combination with PCM damaged the liver function of fish by increasing the serum levels of liver enzymes alanine aminotransferase and alkaline phosphatase. Moreover, our histopathological study demonstrated liver of fish suffered several tissue alterations, such as congestion, hyperemia, infiltration, sinusoidal dilatation, macrovascular fatty degeneration, and pyknotic nuclei after exposure to CPX alone and in combination with PCM. Concerning oxidative stress biomarkers and the expression of genes, we demonstrated that CPX and its mixture, with PCM, increased the levels of antioxidant enzymes and oxidative damage biomarkers and altered the expression of Nrf1, Nrf2, BAX, and CASP3, 6, 8, and 9 in the liver of fish. Last but not least, we demonstrated CPX alone and with PCM induced DNA damage via comet assay and increased the frequency of micronuclei in a concentration-dependent manner in fish. Overall, our results let us point out CPX, even at low concentrations, induces hepatotoxic effects in fish and that its combination with PCM has a negative synergic effect in the liver of this organism.

Assessment of Histopathological Changes in the Liver and Spleen of Mice Infected with Salmonella typhi Following Treatment with Ciprofloxacin

This study evaluated the toxicity of ciprofloxacin to spleen and liver when used for the treatment of mice infected with S. typhi for seven days. The dose concentration used in these experiments was 100mg/kg. Mice were divided into two groups . The first group (negative control) was not given ciprofloxacin, but rather a sterile phosphate buffer solution (PBS) as an alternative. Ciprofloxacin was administered to the second group. After seven days , the animals were sacrificed and organs (liver and spleen) were collected . The histopathological examination showed normal hepatocytes in the liver and normal structure of spleen cells in animals of control group . However, the treated group showed dilated and congested blood vessels with perivascular inflammatory cell cuffing and acute cell swelling in the liver, as well as white pulp activation with an increased number of megakaryocyte cells in the spleen. Therefore, the current study suggests that the concentration of 100 mg/kg of ciprofloxacin is considered to be toxic to hepatocytes and splenocytes of mice during the treatment period.