Toxicity Of Antibiotics Research Articles

A review on Api-products: current scenario of potential contaminants and their food safety concerns

Despite being considered a ‘superfood’, Api-products (Honeybee-derived products) are also linked with heterogeneous health risk factors such as toxic heavy metals, pathogens, antibiotics and pesticide residues due to unscrupulous beekeeping practices. The present work is a holistic approach to extensively studying and mapping various contaminants in Api-products. Thus, this provides an insight into their associated health hazards, such as placental damage, bronchitis hyperactivity, malignancy, renal lesion, neural degeneration, various allergens, etc. According to our findings, Api-products were composed of various perilous components listed down. Toxic heavy metals such as arsenic, cadmium, mercury, and lead were detected in abundance. Lead (120–487000 μg/kg), cadmium (30–25400 μg/kg) and arsenic (9.3–1370 μg/kg) were spotted in bee pollen followed by propolis (cadmium, 30–930 μg/kg) and honey (lead, 1.71–2530 μg/kg) above the acceptable level. Additionally, bifenthrin, triadimefon, lambda-cyhalothrin, and chlorpyrifos were major pesticides found in bee products, except in royal jelly. Also, honey and royal jelly samples were predominantly detected with antibiotics such as tetracyclines, quinolone, nitroimidazole, and sulfonamide. Pathogens ( C. botulinum , Bacillus spp ., Zygosaccharomyces, Aspergillus spp. ) were mostly identified in bee pollen and honey. Still, there is a shortage of evidence related to royal jelly and bee bread which signifies huge research gaps . Furthermore, the current paper emphasises various detection techniques, safety issues, and toxicological concerns related to Api-products, which alarms the urgency of establishing global safety regulations in the future.

Antibiotic nitrofurazone drives the functional dynamics of periphytic protozoan fauna in marine environments

The use of functional traits of a community as a method to measure its functional dynamics in response to environmental change has gained attention because trait-based approaches offer systematic opportunities to understand the interactions between species diversity and ecosystem function. However, the relationship between functional traits of periphytic protozoa and contamination of aquatic habitats with antibiotics is poorly understood. In this study, we investigated the influence of the antibiotic nitrofurazone on functional traits of marine periphytic protozoan fauna. For this purpose, the protozoan assemblages were collected from coastal waters of the Yellow Sea at Qingdao, northern China, during four seasons of a one-year cycle using glass microscope slides as artificial substrates. The test protozoan communities were then exposed to various treatments of nitrofurazone in laboratory bioassay experiments. Our results demonstrated that the modalities of the functional traits of protozoan communities were generally driven by nitrofurazone toxicity. Briefly, R-mode linked to Q-mode (RLQ) and fourth-corner analyses revealed strong positive correlations between functional traits and nitrofurazone treatments. Trait syndromes in terms of body length, width, weight, height, and size to volume ratios were significantly influenced by nitrofurazone exposure. In particular, small and medium body size species of different feeding types, i.e., algivores, bacterivores, raptors or non-selectives, were more sensitive than other protozoan species to higher concentrations of nitrofurazone. Our findings demonstrate that antibiotic toxicity is likely to affect periphytic protozoan community function, shape the functional processes, and induce toxic responses in the community. The findings of this study suggest that periphytic protozoan communities and their functional traits are suitable bioindicators for evaluating the ecotoxicity of nitrofurazone in marine environments.

Responses of cyanobacterium Microcystis aeruginosa under single and repeated ofloxacin exposure

Antibiotics are omnipresent and pseudo-persistent in the environment. Yet, their potential ecological risks under repeated exposure, which is more environmentally relevant, are understudied. Therefore, this study used ofloxacin (OFL) as the probe chemical to investigate the toxic effects of different exposure scenarios―single dose of high concentration (4.0 µg/L) and multiple additions of low concentrations―towards the cyanobacterium Microcystis aeruginosa. Flow cytometry was employed to measure a collection of biomarkers, including endpoints related with biomass, single cell properties and physiological status. Results showed that the single dose of the highest OFL level inhibited cellular growth, chl-a content and cell size of M. aeruginosa. In contrast, OFL induced stronger chl-a autofluorescence and higher doses tended to have more remarkable effects. Repeated low OFL doses can more significantly increase the metabolic activity of M. aeruginosa than a single high dose. Viability and cytoplasmic membrane were not affected by OFL exposure. Oxidative stress was observed for the different exposure scenarios, with fluctuating responses. This study demonstrated the different physiological responses of M. aeruginosa under different OFL exposure scenarios, providing novel insights into the toxicity of antibiotics under repeated exposure.

Sulfamethoxazole (SMX) Alters Immune and Apoptotic Endpoints in Developing Zebrafish (Danio rerio)

Sulfamethoxazole (SMX) is a broad-range bacteriostatic antibiotic widely used in animal and fish farming and is also employed in human medicine. These antibiotics can ultimately end up in the aquatic ecosystem and affect non-target organisms such as fish. To discern the effect of SMX on developing zebrafish embryos and larvae, we investigated a broad range of sub-lethal toxicity endpoints. Higher concentrations of SMX affected survivability, caused hatch delay, and induced malformations including edema of the yolk sac, pericardial effusion, bent tail, and curved spine in developing embryos. Lower levels of SMX provoked an inflammatory response in larvae at seven days post fertilization (dpf), as noted by up-regulation of interferon (ifn-γ) and interleukin 1β (il-1β). SMX also increased the expression of genes related to apoptosis, including BCL2-Associated Agonist of Cell Death (bad) and BCL2 Associated X, Apoptosis Regulator (bax) at 50 µg/L and decreased caspase 3 (casp3) expression in a dose-dependent manner. SMX induced hyperactivity in larval fish at 500 and 2500 µg/L based upon the light/dark preference test. Collectively, this study revealed that exposure to SMX can disrupt the immune system by altering host defense mechanisms as well as transcripts related to apoptosis. These data improve understanding of antibiotic chemical toxicity in aquatic organisms and serves as a baseline for in-depth environmental risk assessment of SMX and antibiotics.

De-Labelling Penicillin Allergy in the Emergency Department

Patients with unconfirmed penicillin allergy (PA) are more likely to be treated with less effective, more toxic, or more expensive antibiotics, which leads to suboptimal medical care and increased costs. This study aims to assess the feasibility of conducting a real-time de-labelling of PA in the Emergency Department (ED).

Response of submerged macrophytes and biofilms to coexisting azithromycin and tetracycline: Antibiotic resistance genes removal, toxicity assessment and microbial properties

Antibiotics, such as azithromycin (AZ), tetracycline (TC), and their related antibiotic resistance genes (ARGs), create serious ecological risks to aquatic organisms. This study examined the response mechanisms of submerged macrophytes and periphytic biofilms to a mixture of AZ and TC pollution and determined the antibiotic removal efficiencies and fate of ARGs. The results showed that the plant-biofilm system had a significant capacity for removing both single and combined antibiotics with removal efficiencies of 93.06% ∼99.80% for AZ and 73.35% ∼97.74% for TC. Higher ARG (tetA, tetC, tetW, ermF, ermX, and ermB) abundances were observed in the biofilm, and subsequent exposure to the antibiotic mixture increased the abundances of these genes. Both single and combined antibiotics triggered antioxidant stress, but antagonistic effects were induced only with mixed AZ and TC exposure. Furthermore, the antibiotics changed the structural characteristics of extracellular polysaccharides and induced alterations in the structure of the biofilm microbial community. Increased N-acylated-l-homoserine lactone confirmed alternations in microbial quorum-sensing. The results extend the understanding of the fate of antibiotics and ARGs when aquatic plants and biofilms are exposed to antibiotic mixtures, as well as the organism's response mechanisms.

Ultrasound-Assisted Synthesis of a ZnO/BiVO4 S-Scheme Heterojunction Photocatalyst for Degradation of the Reactive Red 141 Dye and Oxytetracycline Antibiotic.

The preparation of novel sunlight active photocatalysts for complete removal of pollutants from aqueous solutions is a vital research topic in environmental protection. The present work reports the synthesis of a ZnO/BiVO4 S-scheme heterojunction photocatalyst for degradation of the reactive red dye and oxytetracycline antibiotic in wastewater. ZnO and BiVO4 were first fabricated by a hydrothermal technique, and then, the ZnO/BiVO4 heterostructure was synthesized using an ultrasonic route. An increase of the surface area, compared to that of ZnO, was found in ZnO/BiVO4. The enhancement of charge separation efficiency at the interface was obtained so that a remarkable enhancement of the photocatalytic performance was detected in the prepared heterojunction photocatalyst. Complete detoxification of harmful pollutants was achieved by using the economical solar energy. The removal of the pollutants follows the first-order reaction with the highest rate constant of 0.107 min-1. The stability of the prepared photocatalyst was detected after five cycles of use. The ZnO/BiVO4 S-scheme heterostructure photocatalyst still provides high photoactivity even after five times of use. Hydroxyl radicals play an important role in the removal of the pollutant. This work demonstrates a new route to create the step-scheme heterojunction with high photoactivity for complete removal of the toxic dye and antibiotic in the environment.

Antibiotic Pollution of Planktonic Ecosystems: A Review Focused on Community Analysis and the Causal Chain Linking Individual- and Community-Level Responses.

Antibiotic pollution has become one of the most challenging environmental issues in aquatic ecosystems, with adverse effects on planktonic organisms that occupy the base of the aquatic food chain. However, research regarding this topic has not been systematically reviewed, especially in terms of community-level responses. In this review, we provide an overview of current antibiotic pollution in aquatic environments worldwide. Then, we summarize recent studies concerning the responses of planktonic communities to antibiotics, ranging from individual- to community-level responses. Studies have shown that extremely high concentrations of antibiotics can directly harm the growth and survival of plankton; however, such concentrations are rarely found in natural freshwater. It is more likely that environmentally relevant concentrations of antibiotics will affect the physiological, morphological, and behavioral characteristics of planktonic organisms; influence interspecific interactions among plankton species via asymmetrical responses in species traits; and thus alter the structure and function of the entire planktonic ecosystem. This review highlights the importance of community analysis in revealing antibiotic toxicity. We also encourage the establishment of the causal relationships between impacts at multiple scales in the future for predicting the community-level consequences of antibiotics based on the currently available individual-level evidence.

Efficient Visible-Light-Driven Tetracycline Degradation and Cr(VI) Reduction over a LaNi1-xFexO3 (0 ≤ x ≤ 1)/g-C3N4 Type-II Heterojunction Photocatalyst.

The development of efficient, stable, and visible-light-responsive photocatalysts is crucial to address the pollution of water bodies by toxic heavy metal ions and organic antibiotics. Herein, a series of LaNi1-xFexO3/g-C3N4 heterojunction photocatalysts are prepared by a simple wet chemical method. Moreover, LaNi0.8Fe0.2O3/g-C3N4 composites are characterized by various methods, including structure, morphology, optical, and electrochemical methods and tetracycline degradation and photocatalytic reduction of Cr(VI) under visible light irradiation. Then, the photocatalytic performance of as-prepared LaNi0.8Fe0.2O3/g-C3N4 composites is evaluated. Compared with pure LaNi0.8Fe0.2O3 and g-C3N4, the LaNi0.8Fe0.2O3/g-C3N4 composite photocatalysts exhibit excellent photocatalytic performance due to synergy of doping and constructing heterojunctions. The results show that the doping of Fe ions can increase the concentration of oxygen vacancies, which is ultimately beneficial to the formation of electron traps. Moreover, the type-II heterojunction formed between LaNi0.8Fe0.2O3 and g-C3N4 effectively strengthens the separation and transfer of photoinduced carriers, thereby promoting photocatalytic activity. Furthermore, the photocatalytic activity of the LaNi0.8Fe0.2O3/g-C3N4 photocatalyst remains almost unchanged after three cycles, indicating long-term stability. Ultimately, the photocatalytic mechanism of the LaNi0.8Fe0.2O3/g-C3N4 composites is proposed.

Assessment of toxic mechanisms and mode of action to three different levels of species for 14 antibiotics based on interspecies correlation, excess toxicity, and QSAR

Antibiotics have received much attention owing to their ecotoxicity toward nontarget aquatic creatures. However, the mode of action (MOA) of toxicity against nontarget organisms is unclear in some aquatic organisms. In this study, the comparison of toxicities through interspecies correlations, excess toxicity calculated from toxicity ratio, and quantitative structure-activity relationship (QSAR) was carried out to investigate the MOAs for 14 antibiotics among Daphnia magna, Vibrio fischeri, and Pseudokirchneriella subcapitata. The results showed that interspecies toxicity correlations were very poor between any two of the three species for the 14 antibiotics. The toxicity ratio revealed that most antibiotics exhibited excess toxicity to algae and Daphnia magna but not to V. fischeri, demonstrating that some antibiotics share the same MOA, but some antibiotics share different MOAs among the three different levels of species. P. subcapitata was the most sensitive species, and V. fischeri was the least sensitive species. This is because of the differences in the biouptake and interactions of antibiotics with the target receptors between the three different trophic levels of the species. Molecular docking simulations suggested that the toxicity of antibiotics depends highly on their interactions with target receptors through hydrogen bonds, electrostatic or polar interactions, π bond interactions, and van der Waals forces. QSAR models demonstrated that hydrogen bonding and electrophilicity/nucleophilicity play key roles in the interaction of antibiotics with different receptors in the three species. The toxic mechanisms of antibiotics are attributed to the interactions between electrophilic antibiotics and biological nucleophiles, and hydrogen-bond interactions. These results are valuable for understanding the toxic mechanisms and MOA of the three different levels of species.

Pollution Characteristics and Risk Assessment of Typical Antibiotics and Persistent Organic Pollutants in Reservoir Water Sources

The major task of Chinese water governance has gradually shifted away from water environment protection to water ecology remediation, and the governance of trace organic pollutants, including persistent organic pollutants and antibiotics, has attracted growing concern. The present study examined the seasonal distribution and sources of typical persistent organic pollutants and antibiotics in six representative water sources in the lower reaches of the Yangtze River, as well as their ecological risk to the environment. Six representative surface water and surface sediment samples were collected at different time intervals, i.e., December 2018, March 2019, and June 2019, and the concentrations of nineteen organochlorine pesticides (OCPs), seventeen polychlorinated biphenyls (PCBs), and eight polybrominated diphenyl ethers (PBDEs) were analyzed by GC-MS. The major findings are listed below: ① Endosulfan sulfate, Beta-endosulfan, and methoxychlor were the major persistent organic pollutants (POPs) detected in the sediments from Gaoyou Lake, Gonghu Lake, and Gehu Lake, with concentrations ranging from 9.0 to 10.6 ng/g. ② The target antibiotics in water sources were at relatively low levels. Occurrences of sulfonamide antibiotics in water and surface sediments were NF~37.4 ng·L−1 and NF~47.3 ng·g−1. Concentrations of quinolone antibiotics in the two media were NF~5.3 ng·L−1, 0.4~32.5 ng·g−1. ③ The combined toxicity of antibiotics (risk quotient, RQ) in Lake Gehu was 0.18, which was at a moderate risk level. There was no obvious ecological risk in most water sources affected by POPs. However, there were certain ecological risks in the water sources of Gaoyou Lake, Gonghu Lake, and Sanjiangying, induced by OCPs and PCBs. This study provides a scientific basis for the treatment of antibiotics and organic pollutants in reservoir water sources.

ВИХОДЕЦЬ ІЗ УКРАЇНИ ЗЕЛЬМАН АБРАХАМ ВАКСМАН — ВИДАТНИЙ ВЧЕНИЙ, НОБЕЛІВСЬКИЙ ЛАУРЕАТ, РОДОНАЧАЛЬНИК СТРЕПТОМІЦИНУ ТА СУЧАСНОЇ ЕРИ ПРОТИТУБЕРКУЛЬОЗНОЇ ХІМІОТЕРАПІЇ

Throughout its existence, humanity has experienced both evolution and progress in health matters and borne the burden of complex diseases and shortened life duration. Tuberculosis is an example of a pathology that until recently was a sentence for the patient. Every successful step in the search for tuberculosis treatment (which means saving a life) is priceless. The aim was to study of the biography of Selman Waksman and the history of the streptomycin discovery according to the literature data. Selman Waksman was born in 1888 in a Ukrainian village near Vinnitsa, and immigrated to the United States in 1910. He received a bachelor’s degree in 1915, and in 1916 — a magister degree in the agricultural course of Rutgers College. In 1918, Selman received Ph.D. in Biochemistry in the University of California. Since 1918, he worked in the Department of Soil Microbiology at Rutgers University and studied actinomycetes. In 1923, Waksman discovered that certain actinomycetes produced substances toxic to bacteria, and in 1939 he began an extensive research program to determine the nature of the substances by which various soil microbes destroyed each other. Actinomycin, an effective but toxic antibiotic, was isolated in 1940. In 1942, the antibiotic streptothricin was discovered and studied, a highly active against the M. tuberculosis, but too toxic. In 1943, together with graduate student Albert Schatz, two strains of Actinomyces were isolated, which produced a substance with antibiotic activity — streptomycin. Streptomycin had shown antibiotic activity against several bacteria, including M. tuberculosis. The drug was not toxic to animals. The great practical prospects of streptomycin for the treatment of tuberculosis and other infections led to the award of the Nobel Prize in Physiology or Medicine in 1952. Dr. Waksman introduced and popularized the term “antibiotic” in microbiology. He published more than 447 articles and wrote, independently or with co-authors, 28 books. When the Nobel Prize was awarded to the developer of streptomycin, a drug that saved thousands of human lives, the outstanding scientist was recognized as one of the greatest benefactors of mankind. Key words: Selman Abraham Waksman, streptomycin, tuberculosis, history of medicine.

Evaluation of toxicity and resistant effects of heavy metals and antibiotics on the growth of marine bioluminescent bacteria

Luminescence is the emission of light by an object. Living organisms including certain bacteria are capable of luminescence. Bacteria are the most abundant luminescent organisms in nature. Bacterial luminescence has been studied most extensively in several marine bacteria. Bacterial luminescence is due to the action of the enzyme called luciferase. The luminescent bacteria exist in nature either as free-living bacteria or in symbiotic association with certain marine organisms. Research on luminescent bacteria has always been a fascinating one. In the present study, ten free living luminescent bacteria initially isolated from marine origin were characterized for their tolerance to heavy metals and antibiotics. Copper, zinc, cobalt and cadmium metals at 1 mg/mL concentration have inhibited the growth and luminescence of the all strains except strains 1, 2 and 7. Surprisingly, lead metal at the same concentration dd not inhibit any of the ten strains. However, at 2 mg/mL concentration, similar trend was observed on the growth and luminescence of all the 10 strains. Also, all the tested isolates were sensitive (1 cm >) to all Gram negative and positive antibiotics being tested except isolates 3, 6 and 8, respectively which were resistant (0 – 0.9 cm) to all the antibiotics tested. Thus, the strains isolated from the different sample types have good beneficial potentials such as heavy metal tolerance and antibiotic sensitivity.

The Study of Food Safety of the National Product «Kurt», Produced at the Enterprises of the East Kazakhstan Region

The article presents the results of a study of the national product " Kurt " produced at the enterprises of the East Kazakhstan region . A huge danger for humans is the entry of xenobiotics into the body together with plant , animal food and water , which form toxic metabolites due to biotransformation . About 10-30 % of harmful substances enter the body with water and air , and 70-90 % with food . According to the magnitude of the hazard coefficient , the most priority pollutant of food consumed by the population is nitrates , arsenic , lead , aflotoxin . Therefore , there are acute problems of quality control of food products that guarantee their safety . The purpose of the study is to study the food safety of the national product " Kurt ", produced at the enterprises of the East Kazakhstan region . The technology of production of national fermented milk products is relevant in the market of Kazakhstan today . The following leading dairy enterprises of Kazakhstan, including the East Kazakhstan region , were selected to conduct food safety studies of the national product " Kurt ": Vostok- Milk Corporation LLP, Bagration LLP, Petrosyan IP. When determining the food safety of the national product " Kurt ", indicators of toxic elements , mycotoxins , antibiotics , pesticides and radionuclides were determined . Research was carried out in the testing laboratory for testing products of the Semey branch of the National Center for Expertise and Certification JSC. According to the laboratory , toxic elements , mycotoxins , antibiotics , pesticides and radionuclides corresponded to the norm .

959. It Takes a Village: Reducing Empiric Vancomycin Use by Leveraging Primary Team Pharmacist Oversight of a 72-hour Approval Process

Abstract Background Vancomycin is often initiated empirically in hospitalized patients for broad spectrum gram-positive coverage, however in many cases it is initiated unnecessarily and/or continued empirically for longer durations than necessary. Strategies to facilitate timely discontinuation of vancomycin when unnecessary may reduce antibiotic toxicity (e.g. nephrotoxicity) and the development of bacterial resistance. In large hospital systems, it may not be feasible for stewardship programs to implement prior authorization requirements or prospective audit/feedback for all vancomycin orders. Novel strategies to enlist other clinicians to serve as stewards of antibiotic use are needed. Methods On February 1, 2020, we implemented a protocol requiring providers to obtain approval from the primary team pharmacist to continue empiric vancomycin regimens >72 hours. Primary team pharmacists were provided a list of appropriate indications for vancomycin continuation. After 72 hours, the pharmacist placed a note describing the approved indication or if ASP or ID consult was obtained. We evaluated the standardized antibiotic administration ratio (SAAR) for antibacterial agents for resistant gram-positive infections for FY2019 (pre-protocol) and FY2020 (post-protocol) to assess the impact of this intervention. Vancomycin utilization was also evaluated in days of therapy (DOT)/1000 patient days during both time periods. Results The SAAR for antibacterial agents for resistant gram-positive infections for FY2019 was 1.17 and FY2020 was 1.04 (95% CI (0.87, 0.91), p-value < 0.001). A significant reduction in SAAR was observed in patients admitted to the ICU and floor (Figure 1). Overall vancomycin utilization according to days of therapy/1000 patient days was reduced from 111.13 (FY2019) to 104.08 (FY2020). Conclusion Leveraging the oversight of primary team pharmacists proved to be an effective strategy to reduce empiric vancomycin durations of therapy. Following the implementation of a 72-hour approval protocol with primary team pharmacist oversight, we observed a significant reduction in the SAAR for antibacterials for resistant gram-positive infections with a corresponding reduction in vancomycin utilization. Disclosures All Authors: No reported disclosures.

Recent development in the sustainable remediation of antibiotics: A review

• Antibiotics are emerging contaminants due to their recalcitrant nature. • Antibiotics and their metabolites are detected frequently in the environment. • Antibiotics exert their ecotoxicity on target and non-target organisms. • Sustainable remediation of antibiotics using waste products, biochar, and microbial fuel cells. • Antibiotic remediation future relies on composite or hybrid technologies. Antibiotics are identified as an emerging contaminant due to their persistence in the environment. Antibiotics, due to their accumulation in freshwater sources and wastewater have become a pollutant of concern. Every year million tons of these emerging contaminants are discharged into the water bodies. Through, the feces and urine of humans and animals, the antibiotics and their metabolites enter the environment. Aquatic ecosystems are exposed to persistent pollutants as they escape the wastewater treatment process. Excessive usage of antibiotics has resulted in the generation of antibiotic-resistant genes and bacteria in the environment. To maintain the vitality of the environment, it becomes imperative to mitigate antibiotics and their toxic metabolites. To avoid the adverse consequences on the non-target organisms, their removal from the environment is vital. Various remediation methods such as conventional methods including ion exchange, and precipitation are used for antibiotics degradation, however, the efficacy of the traditional methods is limited due to the production of toxic sludge and the high cost of maintenance. Biological methods such as bioremediation and phytoremediation are sustainable strategies to eradicate antibiotics, hence used widely. There are many reviews on antibiotic bioremediation using microbes and phytoremediation of antibiotics. But not all antibiotics can be remediated using microorganisms, so there is a need for more sustainable removal methods and recent remediation strategies. In the present review, a web-based search for literature published between 2010 to 2022 is carried out. Previous studies reported that living organisms like bacteria, fungi, algae, and plants could be utilized for the degradation of antibiotics. But not all antibiotics could be degraded using bacteria, as bioremediation may get affected by many factors such as inoculum size, microbial strain, and the culture conditions. Therefore, recent remediation techniques such as the use of microbial fuel cells, biochar, and sawdust are used for the possible removal of antibiotics from the environment. For the sustainable elimination of recalcitrant antibiotics, combined processes seem to be a more efficient and permanent solution for bypassing the toxicity of antibiotics

Antibiotic Toxicity Isolated and as Binary Mixture to Freshwater Algae Raphidocelis subcapitata: Growth Inhibition, Prediction Model, and Environmental Risk Assessment.

Antibiotics in aqueous environments can have extremely adverse effects on non-targeted organisms. However, many research projects have only focused on the toxicological evaluation of individual antibiotics in various environments. In the present work, individual and binary mixture toxicity experiments have been conducted with the model organism Raphidocelis subcapitata (R. subcapitata), and a mixture concentration-response curve was established and contrasted with the estimated effects on the basis of both the concentration addition (CA) and the independent action (IA) models. In addition, different risk assessment methods were used and compared to evaluate the environmental risk of binary mixtures. The toxic ranking of the selected antibiotics to R. subcapitata was erythromycin (ERY) > sulfamethoxazole (SMX) > sulfamethazine (SMZ). In general, the conclusion of this study is that the adverse effects of binary mixtures are higher than the individual antibiotics. The CA model and RQSTU are more suitable for toxicity prediction and risk assessment of binary mixtures. This study reveals the potential ecological risks that antibiotics and their mixtures may pose to water ecosystems, thus providing scientific information for environmental quality regulation.

Potentialities of fluorescent carbon nanomaterials as sensor for food analysis.

Food safety and quality are among the most significant and prevalent research areas worldwide. The fabrication of appropriate technical procedures or devices for the recognition of hazardous features in foods is essential to safeguard food materials. In the recent era, developing high-performance sensors based on carbon nanomaterial for food safety investigation has made noteworthy progress. Hence this review briefly highlights the different detection approaches (colorimetric sensor, fluorescence sensor, surface-enhanced Raman scattering, surface plasmon resonance, chemiluminescence, and electroluminescence), functional carbon nanomaterials with various dimensions (quantum dots, graphene quantum dots) and detection mechanisms. Further, this review emphasizes the assimilation of carbon nanomaterials with optical sensors to identify multiple contaminants in food products. The insights of carbon-based nanomaterials optical sensors for pesticides and insecticides, toxic metals, antibiotics, microorganisms, and mycotoxins detection are described in detail. Finally, the opportunities and future perspectives of nanomaterials-based optical analytical approaches for detecting various food contaminants are discussed.

Hyaluronic Acid-Based Antibacterial Hydrogels for Use as Wound Dressings.

Wound dressings have been shifting toward a more active role in the wound-healing process. Hydrated environments with additives to aid in the healing process are currently being explored through the application of hydrocolloid dressings. However, these moist healing environments are also ideal for bacterial growth, leading to the widespread use of antibiotics with concerns of antibiotic resistance and toxicity. To overcome this concern, we present a hydrogel wound dressing consisting of hyaluronic acid (HA) cross-linked with gentamicin. This hydrogel treats bacterial infection locally, lowering the effective dose and reducing the concerns of antibiotic resistance and systemic exposure. Changing the cross-linking density, by using varied amounts of a cross-linker, created gels that provided a sustained release of gentamicin for up to 9 days with a range of adhesive and cohesive properties. Overall, this HA hydrogel could provide an important solution in treating local infection in burns and other dermal injuries.

Black carbon and humic acid alleviate the toxicity of antibiotics to a cyanobacterium Synechocystis sp.

Natural organic matters (NOMs), omnipresent in natural water, challenge the toxicity assessment of pollutants to aquatic organisms due to their complex interactions with chemicals and organisms. Here, we investigated the combined toxicity of one solid NOM (black carbon, BC) or one soluble NOM (humic acid, HA) with antibiotics, roxithromycin (RTM) or gatifloxacin (GAT), to the cyanobacterium Synechocystis sp.. The NOMs alleviated the toxicity of RTM and GAT to Synechocystis sp., and BC had greater alleviation effects than HA due to its stronger adsorption to antibiotics. Antibiotics disturbed the photosynthesis of Synechocystis sp. significantly, which were also mitigated by BC and HA. Proteomic analysis showed that BC up-regulated the pathway of ribosome and photosynthetic antenna protein. GAT down-regulated the pathways of ABC transporter and oxidative phosphorylation. RTM interfered the pathway of porphyrin and chlorophyll metabolism. Furthermore, the addition of BC reduced the number of differentially expressed proteins caused by antibiotics, corroborating its mitigation effects on the toxicity of antibiotics. The disturbance of HA on the pathway of ABC transporters inhibited the internalization of RTM, thus decreasing its toxicity. This study underscores the significance of NOMs in mediating the toxicity of organic pollutants to aquatic organisms in natural waters.