Benzalkonium Research Articles

Investigation of the Resistance of Some Disinfectant Active Substances in ESBL-Producing Enterobacteriaceae

In this study, a total of 200 samples, including 100 neck skin and 100 cecum samples, were collected and analyzed from various poultry slaughterhouses on different sampling days. ESBL-producing Enterobacteriaceae were isolated and ESBL production was confirmed phenotypically by combined disk diffusion and E-test gradient strips. While ESBL production was confirmed in 10 (10%) of 100 neck skin samples, no significant ESBL production could be confirmed in 100 cecal samples. The broth microdilution method of Clinical and Laboratory Standards Institute (CLSI) was used to determine the resistance profiles against benzalkonium chloride (BC), cetylpyridinium chloride (CPC), N-alkyl dimethyl benzyl ammonium chloride (ADBAC) and potassium peroxymonosulfate (PPMS) disinfectants in 10 neck skin isolates with confirmed ESBL production. In the study, it has been determined that MIC50 and MIC90 values were respectively ADBAC (8 and 16 mg/L), BC (16 and 32 mg/L), CPC (16, and 32 mg/L), PPMS (≥ 1024 mg/L). The impacts of Enterobacteriaceae strains on food safety and public health are significant; Disinfectant resistance can lead to increased transmission of antibiotic-resistant bacteria, leading to serious infections in humans that are difficult to treat. For that reason, it is of great importance to develop effective control methods, including appropriate disinfectant use, hand hygiene and appropriate isolation measures, to prevent the spread of disinfectant resistant Enterobacteriaceae strains in food production systems.

Cytisine eye drops for benzalkonium chloride-induced dry eye: safety and efficacy evaluation

This experiment aimed to investigate the feasibility of cytisine (CYT) in treating eye diseases with ocular topical application. An in vitro cytotoxicity test, a hen’s egg test-chorioallantoic membrane (HET-CAM), and a mouse eye tolerance test were used to fully reveal the ocular safety profiles of CYT. For the efficacy evaluations, CYT’s effects on cell wound healing, against H2O2-induced oxidative stress damages on cells, and on benzalkonium chloride (BAC)–induced dry eye disease (DED) in mice were evaluated. Results showed that CYT did not show any cytotoxicities at concentrations no higher than 250 μg/ml, while lipoic acid (α-LA) at 250 μg/ml and BAC at 1.25 μg/ml showed significant cytotoxicities within 48 h incubation. The HET-CAM and mouse eye tolerance test confirmed that 0.5% CYT eye drops demonstrated good safety characteristics. Efficacy evaluations showed that CTY significantly promoted cell migration and wound healing. CYT significantly improved cell survival against H2O2-induced oxidative stress damage by reversing the imbalance between the reactive oxygen species (ROS) and antioxidant defense mechanisms. The animal evaluation of the BAC-induced dry eye model revealed that CYT demonstrated a strong treatment effect, including reversing ocular surface damages, recovering corneal sensitivity, and inhibiting neovascularization; HMGB1/NF-κB signaling was involved in this DED treatment by CTY. In conclusion, CYT had strong experimental treatment efficacy against DED with good ocular safety profiles, and it might be a novel and promising drug for DED.

Role of Mesenchymal Stem Cell-Derived Conditioned Medium in Modulating the Benzalkonium Chloride-Induced Cytotoxic Effects in Cultured Corneal Epithelial Cells In Vitro

Purpose Benzalkonium chloride (BAK) is a common preservative in ophthalmic formulations that causes cytotoxic damage to the corneal epithelial cells. This study aims to explore the role of mesenchymal stem cell (MSC)-derived conditioned medium in modulating the BAK-induced cytotoxic effects in cultured human corneal epithelial cells (HCECs) as a cell-free therapeutic agent. Methods The in vitro cultured HCECs derived from a HCE cell line were treated with BAK (0.001% and 0.005%, diluted in DMEM/F12, v/v) for 15 min, washed with 1xPBS, and allowed to recover for 24 h in human bone marrow MSC-derived conditioned medium (MSC-CM: undiluted (100%) and diluted (50%, v/v)). On the other hand, HCECs were co-incubated with BAK (0.005%, v/v) and MSC-CM (100% and 50%, v/v) for 24 h. The HCEC-derived conditioned medium (HCE-CM) was used as an optimal control for MSC-CM, whereas HCECs cultured in DMEM/F12 were used as a control. The DMEM/F12 was used as the base medium for the culture of HCECs and preparation of HCE- and MSC-CM. The role of MSC-CM in modulating the metabolic activity, cell death, epithelial repair, and proliferation, in BAK-treated HCECs was evaluated using MTT assay, Propidium iodide staining, scratch assay, and Ki-67 staining, respectively. Results Compared to the control, recovery of BAK-treated (0.001% and 0.005%, for 15 min) HCECs in MSC-CM showed significantly reduced cell death with enhanced metabolic activity, epithelial repair, and proliferation. However, in comparison with HCE-CM, the beneficial effects of MSC-CM were predominantly observed at lower BAK concentration (0.001%, for 15 min). Whereas the co-incubation of BAK (0.005%) and MSC-CM for a longer duration (24 h) was marginally beneficial. Conclusions Our results suggest that the MSC-CM is effective in modulating the BAK-induced cell death, retardation of metabolic activity and proliferation in cultured HCECs, particularly at lower concentration (0.001%) and shorter exposure (15 min) of BAK.

Development of a sustainable procedure for smartphone-based colorimetric determination of benzalkonium chloride in pharmaceutical preparations

A sustainable procedure offering green, simple, and rapid analysis was developed to determine benzalkonium chloride (BKC) in pharmaceutical preparations. The determination using smartphones was based on the ion pair colorimetric reaction with bromothymol blue (BTB), which produces a yellow color. The intensity of the product color, which is proportional to the concentration of BKC, was detected and evaluated using a smartphone camera and an image processing application. The procedure was performed in a microliter and was rapidly detected within 1 min after incubation. This offered high throughput at 28 samples per well plate in duplicate. Linear calibration, which was a plot of BKC concentrations and relative red intensities, was in the range of 2.0–24.0 μg/mL with an R2 of 0.997. The limits of detection (LOD) and quantitation (LOQ) were 1.0 and 3.2 μg/mL, respectively. This work was successful in applying it to pharmaceutical materials, disinfectant products, and pharmaceutical products containing BKC. It was discovered that the concentrations of BKC as an active ingredient in pharmaceutical materials were 82% w/v, whereas those in disinfectant products ranged from 0.4 to 2.1% w/v. In pharmaceutical products, ophthalmic drops and nasal sprays contain BKC as preservatives in the 0.01–0.02, and the 0.02% w/v, respectively. The results obtained by the proposed procedure compared with a reference titration method showed no significant differences at a 95% confidence level with 1.2–3.4% RSDs. This promotes the efficiency of pharmaceutical preparations regarding infection prevention and control by ensuring that available disinfectants contain a sufficient concentration of BKC. Additionally, this improves the efficiency of pharmaceutical preparations for quality control of pharmaceutical products by ensuring that the available preservatives maintain a sufficient concentration throughout the lifespan of the products.

Decoding Klebsiella pneumoniae in poultry chain: unveiling genetic landscape, antibiotic resistance, and biocide tolerance in non-clinical reservoirs

The rise of antibiotic resistance in the food chain is influenced by the use of antimicrobial agents, such as antibiotics, metals, and biocides, throughout the entire farm-to-fork continuum. Besides, non-clinical reservoirs potentially contribute to the transmission of critical pathogens such as multidrug-resistant (MDR) Klebsiella pneumoniae. However, limited knowledge exists about the population structure and genomic diversity of K. pneumoniae circulating in conventional poultry production. We conducted a comprehensive characterization of K. pneumoniae across the whole chicken production chain (7 farms; 14 flocks + environment + meat, 56 samples; 2019–2022), exploring factors beyond antibiotics, like copper and quaternary ammonium compounds (QACs). Clonal diversity and adaptive features of K. pneumoniae were characterized through cultural, molecular (FT-IR), and whole-genome-sequencing (WGS) approaches. All except one flock were positive for K. pneumoniae with a significant increase (p < 0.05) from early (n = 1/14) to pre-slaughter (n = 11/14) stages, most (n = 6/7) persisting in chicken meat batches. Colistin-resistant K. pneumoniae rates were low (4%-n = 1/24 positive samples), while most samples carried MDR strains (67%-n = 16/24) and copper-tolerant isolates (63%-n = 15/24, with sil and pco gene clusters; MICCuSO4 ≥ 16 mM), particularly at pre-slaughter. Benzalkonium chloride consistently exhibited activity against K. pneumoniae (MIC/MBC range = 4–64 mg/L) from representative strains independently of the presence or absence of genes linked to QACs tolerance. A polyclonal K. pneumoniae population, discriminated by FT-IR and WGS, included various lineages dispersed throughout the chicken’s lifecycle at the farm (ST29-KL124, ST11-KL106, ST15-KL19, ST1228-KL38), until the meat (ST1-KL19, ST11-KL111, ST6405-KL109, and ST6406-CG147-KL111), or over years (ST631-49 KL109, ST6651-KL107, ST6406-CG147-KL111). Notably, some lineages were identical to those from human clinical isolates. WGS also revealed F-type multireplicon plasmids carrying sil + pco (copper) co-located with qacEΔ1 ± qacF (QACs) and antibiotic resistance genes like those disseminated in humans. In conclusion, chicken farms and their derived meat are significant reservoirs for diverse K. pneumoniae clones enriched in antibiotic resistance and metal tolerance genes, some exhibiting genetic similarities with human clinical strains. Further research is imperative to unravel the factors influencing K. pneumoniae persistence and dissemination within poultry production, contributing to improved food safety risk management. This study underscores the significance of understanding the interplay between antimicrobial control strategies and non-clinical sources to effectively address the spread of antimicrobial resistance.

Current Strategies in Controlling Aspergillus flavus and Aflatoxins in Grains during Storage: A Review

Aspergillus flavus is a ubiquitous pathogen that can infect many foods and grains, and it produces large amounts of aflatoxins during their storage. Aflatoxins are considered highly toxic and carcinogenic to humans, and they cause great damage to crop production, food security, and human health. Thus, controlling A. flavus and aflatoxins in grains presents a great challenge to humans worldwide. Over the past decade, many strategies have been demonstrated to be useful in controlling A. flavus and aflatoxins during food storage. These methods involve physical agents, chemical agents, biological agents, etc. Some of these methods are currently used in actual production. In this review, we summarize the reported methods for controlling A. flavus and aflatoxins during food storage in the past ten years and elucidate their advantages and disadvantages. The methods discussed include irradiation technology; low oxygen atmospheres; chemical fungicides (benzalkonium chloride, iodine, ammonium bicarbonate, and phenolic and azole compounds); biological agents from plants, animals, and micro-organisms; and aflatoxin elimination methods. We expect that this review will promote the applications of current strategies and be useful for the development of novel technologies to prevent or eliminate A. flavus and aflatoxins in food and feed during storage.

In vitro study of the bactericidal activity for new derivatives of quaternary ammonium salts based on pyridoxine against gram-positive/gram-negative bacteria

Background: preventive care and successful treatment of infectious diseases (including hospital-acquired infections) are among the most important tasks of modern healthcare. There are not many effective antiseptics and disinfectants to solve this problem. Quaternary ammonium salts are currently one of the promising classes of disinfectants but their use is limited by the ability of microorganisms to develop resistance to these compounds. Modification of QAS with substituents of various natures is a possible way to solve this problem.
 Aims: in this work a bactericidal activity comparative analysis for two original quaternary ammonium compounds based on pyridoxine was carried out in comparison with benzalkonium chloride.
 Materials and methods: the bactericidal activity of 0.1% and 0.2% aqueous solutions of original QACs based on pyridoxine were studied against two widespread pathogens: S. aureus and E. coli. Antibacterial activity data were obtained using a standard in vitro test (bactericidal activity test on a metal surface, exposure time 1, 5 and 15 minutes). In addition to standard conditions, antibacterial efficacy was also studied under protein loading conditions (adding BSA solution to the surface).
 Results: for the studied compounds the RF (reduction factor - reduction lgCFU of microorganisms) was on average ≥ 3. Complicating the model conditions in the form of protein load led to a decrease in efficiency by 1-3 orders. We have also observed an interesting effect of exposure time-dependent specificity reversal to the S. aureus and E. coli.
 Conclusions: The obtained results showed high activity of the studied compounds (corresponding to the effectiveness criterion RF≥3 for commercial compounds used in this field).

Innovative multifunctional nanocapsules with antibacterial, perfume, and UV-initiated coating properties

Polymer nanocapsules containing fragrance were fabricated for antibacterial, pleasing scent and UV-coating applications. Poly (2-methacryloyloxy dodecyl dimethyl ammonium chloride-4-allyloxy-2-hydroxybenzophenone)-block-polymethyl methacrylate-iodide (P(QAC12-BP)-b-PMMA-I) was first synthesized by solution iodine transfer polymerization (solution ITP) for use as a polymerizable surfactant in miniemulsion polymerization where benzalkonium chloride (BKC) was used as a cosurfactant. The nanocapsules were prepared using poly(methyl methacrylate–divinylbenzene) (P(MMA–DVB)) as a shell, whereas mangosteen oil (MO) was used as a fragrance core model for aroma. High colloidal stability nanocapsules with a size of about 213 nm were obtained. The nanocapsule surface contained QAC12 segments of 15.10 µmol/g-capsule (UV measurement), giving the high positive charge (+70 mV). An essential oil encapsulated inside the nanocapsule had a high encapsulation efficiency (>90%). The nanocapsules effectively inhibited bacterial growth because of QAC12 and BKC on their surface. The nanocapsules are able to coat the substrate via UV-activated covalent bonds of the BP segment.

Benzalkonium chloride modification of tin oxide to enhance the performance of perovskite solar cells

For planar perovskite solar cells (PSCs), tin oxide (SnO2) is a perfect electron transport material. However, owing to nanoparticle agglomeration and defects, the advantages of SnO2 cannot be effectively utilized. Herein, a cationic surfactant, benzalkonium chloride (BAC) is introduced into SnO2 precursor solution to prevent the aggregation of SnO2. Thus, a uniform and free of pinhole SnO2 electron transport layer (ETL) is obtained, which supports the formation of high-quality perovskite layer (PVK). The introduction of BAC adjusts the energy level of ETL and improves the electron transport in the buried interface. Moreover, the BAC-modification reduces and passivates the defects on the surface of SnO2 and perovskite films. Consequently, BAC-modified PSCs achieves a champion efficiency of 23.49% with an impressive fill factor of 84.50%. The unpackaged device maintains an initial efficiency of 91.4% after 1000 h of storage in dark at 25±5 °C and 25±5% relative humidity.

Asymmetric porous composite hydrogel patch for microenvironment-adapted repair of contaminated abdominal wall defects

Effective antibacterial property and long-term mechanical support are essential for the repair of complex abdominal wall defects associated with infection. However, clinically available repair materials often fail to meet these requirements, resulting in high surgical failure rate and complications. In this study, an asymmetric porous composite hydrogel patch (cCS/PVA@BAC) with antibacterial, anti-adhesion, pro-healing, and durable mechanical support properties is designed for the efficiently repair of contaminated abdominal wall defects. By stepwise phase-conversion and facile immersion, robust and stable polyvinyl alcohol hydrogel (PVAH) is integrated with the biocompatible composite hydrogel comprising chitosan and carboxymethyl chitosan (cCS), and benzalkonium chloride (BAC) is loaded to enhance the antibacterial property. The cCS layer in cCS/PVA@BAC has an extracellular matrix-like structure, which can promote fibroblasts adhesion and wound healing. In contrast, the PVAH layer on the other side has a smooth and dense structure, which can reduce fibroblasts adhesion and prevent visceral adhesion. In addition, the composite hydrogel patch has good anti-swelling and anti-deformation properties as well as stable mechanical strength, thus can withstand high intraperitoneal pressure in the wet internal microenvironment. The loaded BAC can efficiently kill bacteria, and improve the local inflammatory microenvironment. With these advantages, cCS/PVA@BAC can significantly reduce inflammation, promote tissue remodeling, and accelerate the healing of contaminated abdominal wall defects in a rat model. These findings suggest a potential use of multifunctional hydrogel patch as an ideal material for effective repair of contaminated soft tissue defects.

Biological and Synthetic Surfactants Increase Class I Integron Prevalence in Ex Situ Biofilms.

The role of biocides in the spread of antimicrobial resistance (AMR) has been addressed but only a few studies focus on the impact of surfactants on microbial diversity and AMR, although they are common constituents of cleaners, disinfectants, and personal care products and are thus released into the environment in large quantities. In this study, we used a static ex situ biofilm model to examine the development of four biofilms exposed to surfactants and analyzed the biofilms for their prevalence of class I integrons as a proxy for the overall abundance of AMR in a sample. We furthermore determined the shift in bacterial community composition by high-resolution melt analysis and 16S ribosomal RNA (16S rRNA) gene sequencing. Depending on the initial intrinsic prevalence of class I integrons in the respective ex situ biofilm, benzalkonium chloride, alkylbenzene sulfonate, and cocamidopropyl betaine increased its prevalence by up to 6.5× on average. For fatty alcohol ethoxylate and the biosurfactants sophorolipid and rhamnolipid, the mean increase did not exceed 2.5-fold. Across all surfactants, the increase in class I integrons was accompanied by a shift in bacterial community composition. Especially benzalkonium chloride, cocamidopropyl betaine, and alkylbenzene sulfonate changed the communities, while fatty alcohol ethoxylate, sophorolipid, and rhamnolipid had a lower effect on the bacterial biofilm composition.

Optimisation of the composition of safe dental gel with IL-1β antagonist for the treatment of inflammatory periodontal diseases

Aim. The study aims to develop the composition of the oromucosal gel with the IL-1β interleukin antagonist for complex treatment of inflammatory periodontal diseases. Materials and methods. Experimental studies were conducted based on the Department of Medicines Technology of Zaporizhzhia State Medical and Pharmaceutical University and the Training Medical and Laboratory Center of Zaporizhzhia State Medical and Pharmaceutical University of the Ministry of Health of Ukraine. As an active component, in the recipe of oromucosal gel, used antagonist of the interleukin IL-1B. Excipients: D-panthenol (the plasticizer), carboxymethylcellulose sodium salt (the viscosity modifier and mucoadhesive component), Tween-80 (the enhancer absorption), benzalkonium chloride (the preservative), sodium hydrophosphate + citric acid (the phosphate buffer solution), purified water. The experiments used existing and auxiliary ingredients of pharmaceutical purity, which were obtained from Sinbias LLC, Istok-Plus LLC, LLC “Mobile Medical”. For the design of the experiment, the methodology of the response surface (Box-Behnken Design) is used: Na CMC, Tween-80, D-panthenol; and four answers: pH, viscosity test, system type, mucoadhesive properties. Research methods: rheological research (viscosity test, amplitude test, frequency test, mucoadhesive test, thixotropy test) performed in oscillation mode on the modular compact Rheometer Anton Paar MCR 302 (CP50-1 SN71317), which, compared to cylindrical devices, requires a much smaller amount of gel sample and allows the planned tests in the oscillation mode, the temperature in the experiments was provided with a built-in thermostat (Peltier Temperature Control, C-PTD 200). Pharmaco-toxicological studies were conducted on 46 white outbred rats of both sexes, weighing 160–180 grams, which were received from Vivarium by the Institute of Pharmacology and Toxicology. The studies were performed on enough animals, all manipulations were carried out by the provisions on the use of animals in biomedical experiments. The results of the study were calculated using the standard statistical package of the Statistica for Windows 13 (StatSoft Inc., No. JPZ804I382130ARCN10-J), as well as SPSS 16.0, Microsoft Office Excel 2003. Results. According to the design of the experiment, it is established that the components of the system do not change the value of pH in experimental oromucosal gels (6.5500 ± 0.0334). The Anova for Quadratic Model statistical analysis data certify the significant impact of Na CMC, and Tween-80 factors on the viscous characteristics of oromucosal gels (F-value > p-value). Comparison of mucoadhesive characteristics of the studied samples of oromucosal gels was made using dynamic mechanical analysis and the results of statistical analysis of ANOVA for Quadratic Model highlight the significant influence of Na CMC, D-panthenol, Tween-80. Optimized oromucosal gel test data is obtained that its structure is restored after the applied effort, namely the restoration of the structure after 10 seconds occurs by 69.5 %, after 30 s by 76.1 %, after 180 s by 85.4 %, after 180 s which allows to predict the stability of the dosage form, both after manufacture and after use. Conclusions. The composition of the oromucosal gel of anti-inflammatory action with the IL-1β interleukin antagonist for the complex treatment of inflammatory diseases of periodontal is developed. The optimized composition of the oromucosal gel obtained has satisfactory performance of kinetic stability and thixotropic properties. The developed gel for dentistry meets all the requirements for harmlessness and safety for dosage forms of this group toxicity, lack of local irritant and allergic action.

Exposure to potentially harmful excipients in medications among neonates at a state hospital in Malaysia

Objectives This study aimed to determine the incidence, types and predictors of Potentially Harmful Excipients (PHE) exposure among hospitalized neonates. Methods A prospective observational study was conducted from March to April 2022 in neonatal wards at a state hospital in Malaysia. The PHEs of interest were aspartame, benzalkonium chloride, benzyl alcohol, benzoic acid or benzoates, ethanol, parabens, polysorbate 80, propylene glycol, saccharin sodium, sorbitol and sulfites. Product information leaflets (PILs) and summaries of product characteristics (SPCs) were referred to obtain information on active pharmaceutical ingredient, strength, trade name as well as type and amount of the excipients. Results A total of 108 neonates were recruited and 97.2% of them were exposed to at least one PHE. Parabens (47.2%) and sulfites (27.5%) were the two most commonly administered PHEs. Benzyl alcohol is contraindicated in neonates but was administered to 8% of neonates in this study. The median daily dose of ethanol (24.11 mg/kg/day, IQR 19.73, 28.49) exceeded the acceptable daily intake (ADI) by four times. However, the dose was not available for all PHEs as this information is not always available in the PIL or SPC. Administration of cardiovascular drugs was associated with a higher risk of exposure to any PHE (OR 6.38, CI 2.75, 14.79, p-value < 0.001). Conclusion The exposure of PHE among neonates in this study is high with certain PHEs exceeding the ADI. It highlights the need for certain strategies to be implemented to reduce such exposure in neonates.

Investigating pharmaceuticals and personal care products in Musi River: A exploratory study in Hyderabad, India

This study investigated the presence of 46 pharmaceuticals and personal care products (PPCPs), including antibiotics, anti-inflammatory, antifungal, surfactant, antidepressants, and anticonvulsants, in wastewater samples collected from 11 sites along the Musi River in Hyderabad, India. These samples were obtained from diverse points along the river, representing urban, industrial, and hospital-related sources. This strategic selection ensures a comprehensive assessment of water quality, covering areas of varying population density and industrial activity. The samples were extracted for PPCPs using solid-phase extraction and quantified using ultra-performance liquid chromatography-tandem mass spectrometry in multiple reaction mode. Of the 46, 16 target analytes were detected at concentrations ranging from 0.01 ± 0.001 μg/L (for fluoxetine) to 19.295 ± 4.16 μg/L (for ciprofloxacin). An ecological risk assessment was conducted in terms of risk quotient (RQ) for acute and chronic effects for three trophic levels of aquatic organisms (algae, fish, and invertebrates) for each detected contaminant at every site. In the case of acute toxicity, high RQ values (>>1) were obtained for the antibiotics, naproxen, diclofenac, caffeine, fluconazole, propyl paraben, fluoxetine, and benzalkonium chloride C-12. In the case of chronic toxicity, high RQ values (>>1) were estimated for some of the commonly used PPCPs. This study aimed to investigate the contamination levels of PPCPs in various wastewater discharge points along the Musi River in Hyderabad, a densely populated urban center with a population density of up to 45,000/sq km. Additionally, the research conducted an ecotoxicological risk assessment to evaluate the risk posed by these pollutants to three trophic levels (algae, fish, and invertebrates) using RQ analysis. Notably, this study represents the first attempt to conduct such an assessment in this region, providing valuable insights into environmental health and pollution management.

Consumption of Limosilactobacillus fermentum Inhibits Corneal Damage and Inflammation in Dry Eye Disease Mouse Model through Regulating the Gut Microbiome.

The present study investigated the effect of orally administered Limosilactobacillus fermentum HY7302 (HY7302) on the relationship between ocular tissue and the microbiome in a corneal injury dry eye mouse model. Specifically, 0.1% benzalkonium chloride (BAC) was applied to the ocular surface for 14 days to induce corneal injury in male Balb/c mice. During the BAC treatment period, HY7302 (1 × 108 CFU/kg/day or 1 × 109 CFU/kg/day) or an omega-3 positive control (400 mg/kg/day) were administered orally (n = eight/group). To examine the signaling pathways affected by the HY7302 treatment, the in vitro effects of HY7302 on the tight junctions and the inflammatory response were investigated in the mouse colon epithelial cell line, CMT-93. BAC exposure decreased tear production, induced ocular inflammation and corneal epithelial detachment, and altered the gut microbiota. However, oral administration of HY7302 restored tear secretion and decreased corneal epithelial detachment in BAC-treated corneal injury mice. Further, HY7302 alleviated corneal inflammation via modulation of matrix metalloproteinase-9 (MMP-9) expression and affeted alterations in gut microbiota composition. These findings suggest that the gut-eye axis interaction between gut microbiota and corneal tissue affects disease severity in corneal injury, and that the alteration of the microbiota by HY7302 could improve eye health by regulating the inflammatory response.

Potential health risks to disinfection workers from exposure to active substances in COVID-19 biocidal products

The importance of disinfection has recently been emphasized due to the increasing risk of the spread of infections such as coronavirus disease-2019 (COVID-19). In addition, disinfection for preventing the spread of COVID-19 is highly recommended. The increased use of biocidal products raises concerns regarding the potential health risks from exposure among disinfection workers. This study aimed to assess these exposure and health risks using questionnaires targeting disinfection workers who were exposed to the active substances in biocidal products used for disinfection during the COVID-19 pandemic. A follow-up survey was conducted among 271 disinfection workers for 10 working days within two weeks, and exposure factors with reference to disinfection were evaluated through interview-administered questionnaires. An exposure algorithm was used to evaluate the exposure of disinfection workers during disinfection. The hazard index (HI) was calculated by dividing the inhalation concentration obtained using the exposure algorithm and the dermal dose according to occupational exposure limits (OEL). A sensitivity analysis was conducted to identify the exposure factors with the greatest impact on the inhalation and dermal exposure algorithms. A logistic regression analysis was performed to verify the relationship with health effects and sociodemographic and exposure characteristics. The average number of disinfections performed during 10 working days was 17.5 ± 12.3 times. The type of disinfection work was divided into 2806 cases of COVID-19 prevention and disinfection and 1956 cases of regular pesticide application to prevent and remove any pests. The HI was ≥1, indicating a potential health risk, with the use of ethanol (6.50E+00), quaternary ammonium compounds (QACs; 1.49E+01), and benzalkonium chloride (BKC; 1.73E+00). Dermal exposure was more hazardous than inhalation exposure for 6 of the 11 active substances in biocidal products. The weight fraction and exposure time were the factors that most significantly influenced the inhalation and dermal exposure algorithms in the sensitivity analysis. Higher exposure concentrations were more likely to affect health (AOR: 3.239, 95% CI: 1.155–9.082). This study provides valuable information regarding the exposure and risk of disinfection workers to 11 biocidal active substances included in common disinfectants. Our results suggest that the use of ethanol, BKC, and QACs has potential health risks to disinfection workers, with a higher possibility of negative health impacts with increasing exposure concentration.

Differential Effects of Benzalkonium Chloride on Human Trabecular Meshwork Cells Not Treated or Treated with Transforming Growth Factor-β2 or Dexamethasone.

Purpose: The objective of the present study was to evaluate the effects of low concentrations of benzalkonium chloride (BAC) (10-7%, 10-6%, or 10-5%) on healthy and glaucomatous human trabecular meshwork (HTM) cells. For this purpose, we used in vitro models replicating a healthy HTM and HTM with primary open-angle glaucoma (POAG) or steroid-induced glaucoma (SG) using two-dimensional (2D) cultures of HTM cells not treated or treated with a 5 ng/mL solution of transforming growth factor-β2 or 250 nM dexamethasone (DEX). Methods: Analyses were carried out for (1) the intercellular affinity function of 2D HTM monolayers, as determined by transepithelial electrical resistance (TEER) measurements; (2) cell viability; (3) cellular metabolism by using a Seahorse bioanalyzer; and (4) expression of extracellular matrix (ECM) molecules, an ECM modulator, and cell junction-related molecules. Results: In the absence and presence of BAC (10-7% or 10-5%), intercellular affinity function determined by TEER and cellular metabolic activities were significantly and dose dependently affected in both healthy and glaucomatous HTM cells despite the fact that there was no significant decrease in cell viabilities. However, the effects based on TEER values were significantly greater in the healthy HTM. The mRNA expression of several molecules that were tested was not substantially modulated by these concentrations of BAC. Conclusions: The findings reported herein suggest that low concentrations of BAC may have unfavorable adverse effects on cellular metabolic capacity by inducing increases in the intercellular affinity properties of the HTM, but those effects of BAC were different in healthy and glaucomatous HTM cells.

Sanitizers Used for Fungal Spoilage Control in Dry-Fermented Cured Meat Production

Contamination caused by fungi stands out as a significant microbiological issue in the food industry, particularly leading to premature spoilage across various food segments, including the dry-fermented meat industry. The emergence of undesired fungi on product surfaces results in substantial economic losses. Once microorganisms infiltrate the food, contamination ensues, and their subsequent proliferation can adversely impact the product’s appearance, odor, flavor, and texture. This, in turn, leads to consumer rejection and negatively affects the commercial brand. Additionally, concerns persist regarding the potential presence of mycotoxins in these products. Given the detrimental effects of spoilage fungi in the food industry, practices such as thorough cleaning and sanitization become crucial to prevent contamination and subsequent premature deterioration. These measures play a pivotal role in ensuring the quality and safety of food, while also extending the shelf life of products. This review delves into the advantages, disadvantages, and factors that may influence the efficacy of commonly used sanitizers in the dry-fermented cured meat industry, including substances like sodium hypochlorite, peracetic acid, and benzalkonium chloride.

Impedance-based in vitro eye irritation testing enables the categorization of diluted chemicals

Products containing chemicals with eye irritation potential need to be labeled with the respective hazard symbol. To avoid the testing of numerous dilutions of chemicals on animals, their labeling is directed by a theoretical approach. In this report, a previously described in vitro tissue model of the cornea based on human epithelial cells was used for eye irritation testing of dilutions. As a sensitive and non-destructive method to analyze the barrier function of the epithelium, impedance spectroscopy was applied. Moreover, the morphology and viability of the epithelial models were assessed. We tested four chemicals that, neatly, cause severe damage to the eye: tetrahydrofuran, acetic acid, diethylethanolamine, and benzalkonium chloride. With our test method, we were able to determine the concentrations of the chemicals which are critical for the integrity of the cornea. The threshold was < 0.1% for the most and > 5% for the least toxic substance. The described test system is not only an alternative for animal models but also for the theoretical examination of the hazard potential of diluted chemicals. By using the advantages of tissue engineering and non-destructive analysis tools, we can achieve more precise and safer labeling of the eye irritation potential of products.

Formulation and Optimization of Intra Nasal Niosomal Gel of Kynurenic Acid: In Vitro in Vivo Characterization

Kynurenic acid's (KNA) inability to cross the blood brain barrier (BBB) severely limits its usage as a neuroprotective drug, despite the fact that it may have significant therapeutic effects in neurological illnesses. Drug delivery devices are one of the new avenues we're exploring as a means for KNA to enter the brain. Due to its low absorption when taken orally, medication formulation faces a significant hurdle. Here, nasal drug delivery has emerged as a popular alternate method for increasing medication bioavailability. In light of this, the current investigation set out to increase KNA bioavailability by means of an intranasal formulation based on niosomal technology. Rapid onset and evasion of first-pass metabolism are both offered by the nasal route, whereas niosomes protect hydrophilic medicines inside their core. For the purpose of determining entrapment efficiency, particle size, and in vitro drug release, niosomes were synthesized by combining lipid, nonionic surfactant, and cholesterol in distinct ratios. With a vesicle size of 248.51±1.54nm, the optimized niosomal formulation demonstrated a superior drug content (DC) of 98216±0.11% and an entrapment efficiency (EE) of 89.23±0.35. The formulation also contained cholesterol in an equal proportion (1:1). A value of 24 minutes was shown in the in vitro drug diffusion testing, indicating that the formulation exhibited prolonged activity. Gelation occurred at 37 ⁰C, which is the body's physiological temperature, and the optimum in situ gel, which contained 1:2 carbopol 934 and benzalkonium chloride, had a t90 value of 24 hours, indicating prolonged activity. In comparison to KNA oral suspension, the results showed that the KNA-loaded niosomal gel had a much higher relative bioavailability and improved drug penetration through the nasal mucosa