Germicidal Properties Research Articles

Biological activity of the essential oil of Drimys winteri.

In the Chilean indigenous culture, the tree Drimys winteri (Winteraceae) Canelo is of great importance and is considered the sacred Mapuche tree. It has antibacterial and disinfectant properties and is used in the treatment of various diseases, such as fevers, ulcers, cancers, and respiratory tract problems. The essential oil obtained from D. winteri, DW_EO, is bioactive, possesses insecticidal and repellent properties against pests, and shows activity toward plant growth regulators. It also has a phytotoxic effect against the growth and germination of weeds. The essential oil obtained from the leaves and bark of Drimys winteri has demonstrated antifungal, immunomodulatory, anti-inflammatory, and anticancer properties in in vitro and in vivo studies. It also possesses antioxidant activity and antibacterial effects. The essential oil contains monoterpenes such as zafrol, pinenes, and linalool, among others, that contribute to its bioactivity. The DW_EO and bioactive compounds have great potential in various applications in medicine, industrial food, sanitizer, and other areas.

Fabrication of reusable bioprotective nanofabric with passive nano-Ag/Joule thermal disinfection properties for real-time wireless fine biomotion and gesture sensing

The frequent outbreaks of new infectious diseases, with increased difficulty in prevention and control, have raised higher requirements for bio-protective smart textiles. However, current wearable sensing materials face challenges with thermal and humidity comfort, bioprotection, reusability, self-disinfection, and wireless real-time sensing ability. Herein, an ultralight and breathable sandwich-structured interlayer nanofiber composite consisting of two outer microporous layers of polyimide nanofibers embedded with AgNPs (Ag@PINFs) and one nanoporous conductive layer (＜100 nm) of carbon nanotubes (CNTs) have been demonstrated by in-situ reduction, electrospinning, and suction filtration to improve the triboelectric output performance and impart passive/active self-disinfection abilities to triboelectric nanogenerators (TENGs). The TENG was designed with a triple bio-protection function. This included a passive physical barrier effect, nano-Ag active disinfection, and active Joule-heat disinfection function, which ensures the reusability of TENG. As-prepared TENG possessed the following advantages: (i) good moisture-penetrability; (ii) good water and blood penetration resistance (≥17.2 kPa; ≥7kpa); (iii) improved triboelectric output performances (∼1.6 W/m2 at Ag content of 500 mg/kg); (iv) ultrahigh UV resistance (UPF＞6480); (v) high particle and wet/dry microbial filtration performance (PFE = 99.95%; wet microbial penetration time＞75 min; penetrated dry microbial: lg(cfu)=0); (vi) active bactericidal abilities with killing rates of ∼100% against E. Coli and S. aureus at Ag content of ≥ 70 mg/kg; (vii) high Joule heat self-disinfection efficiency with killing rates of 100% at applied voltage of ≥ 5 V; (viii) a wireless real-time sensing ability to distinguish fine biomotion such as swallowing, coughing, and normal speech and shouting, as well as recognizing hand gesture by developed two/four-channel wearable wireless monitoring system (∼18 g). The TENG has trinity performances including bio-protection, self-disinfection, and wireless fine biomotion and gesture sensing, which has potential applications in medical field.

Assessing passive thermosyphon solar water heater as low-cost, sustainable water disinfection technology: Leveraging the Germicidal effect of copper and thermal convection loops

This study investigated the passive thermosyphon solar water heater (TSWH) as a domestic size point-of-use water disinfection treatment system for inactivating bacteria by utilizing both the germicidal properties of copper in heat exchanger and the heat generated in thermal convection loops. Additionally, life cycle analysis and manufacturing cost analysis were conducted to reveal its environmental and economic benefits. Initially, the germicidal capacity of copper tube against E. coli and total coliform in rapidly flowing polluted water was tested in laboratory settings with contact times ranging from 1.5 to 94 min. Without any additional heat, the copper tubes achieved 99.9% (log 3.01) removal of E. coli, and 99.24% (log 2.12) removal of total coliform after 94 min of contact. In the presence of heat (50–80 ºC), complete removal of the bacteria was achieved after only 1.5 mins of contact time at 50ºC. A domestic-sized passive TSWH with a copper tube heat exchanger was evaluated for disinfecting 20 L/day of microbiologically polluted tap water and synthetic groundwater in a field study. The average contact time of polluted water in copper tube heat exchanger was 5.58±1.2 min in the morning (with an outlet water temperature of 87.3 ºC), and 11.83±1.41 min in the afternoon (with an outlet water temperature of 78±5.1 ºC). These contact times and temperatures, achieved throughout the year, were sufficient to meet the required minimum for complete bacterial removal in the synthetic groundwater. Importantly, the system achieved complete inactivation of pathogens at pasteurization temperatures below 75 ºC, relying solely on the combined effect of copper and thermal convection loops, without pumps or electricity. Compared to an active TSWH using circulating pumps and controls, the passive system generated 62.2% less green house gas, had 55.5% lower cumulative energy demand and cost 323.3 $ compared to 544.64 $. Highlighting significant economic and environmental benefits, the passive TSWH offers a promising solution for disinfecting water in low-income areas with limited access to safe water.

Toxicological properties of plant-based disinfectants

The article presents the results of research on the toxicity determination of phytopreparations in the composition of common powdery mildew + calamus + pear Late November + bischofite; common powdery mildew + calamus + bischofite; pear Late November + bischofite, which have a universally broad spectrum of bactericidal action against Staphylococcus aureus and Escherichia coli. When studying the toxicity of phytopreparations on guppy fish, it was found that when adding the infusion to water in the composition of common powdery mildew + calamus + pear Late November + bischofite with exposures of 30 minutes and 60 minutes, all fish in a group of 10 had an adverse reaction. With an exposure of 24 hours, mortality reached up to 20 %. The highest fish mortality occurred at 24 hours in the composition of common powdery mildew + calamus + bischofite, with a mortality rate of 40 %. The composition of pear in late November + bischofite showed no signs of toxicity; all fish in the group remained alive during the study. Visually, motor activity, behavioral reactions, changes in skin pigmentation, and breathing intensity were average. The survey of skin-irritating effects of phytopreparations was conducted on laboratory animals in 20 individuals – Alaska breed rabbits. It was established that during the observation period, the following signs were absent: the presence of temperature; moderately expressed, expressed, and sharply expressed erythema; pain (with a slight thickening of the skin followed by flaking); pain, swelling, and ulcers (thickening of the skin in the application area on the rabbit). After applying phytopreparations to the skin of rabbits with exposures of 1 hour, 24 hours, 48 hours, and 72 hours, no behavioral and visual changes of an inflammatory nature were detected. When applied to the animal's skin, the investigated plant-based disinfectants do not cause irritating, necrotic, or absorptive effects. Throughout the observation period, no visible changes were observed in laboratory animals' experimental and control groups. The conducted research indicates the possibility of safe application of these plant-based disinfectants in the presence of animals.

BT100, a three-in-one, multipurpose disinfecting, deodorizing, and air-cleaning solution with an effective, gradual, and continuous gaseous chlorine dioxide-releasing substance

Aerosols carrying viruses that are released from the oral cavity of infected individuals are the primary, if not the only, means of transmission during viral respiratory disease epidemics. This makes crowded rooms and tiny, enclosed public areas like bathrooms prime environments for the transmission of diseases. Volatile organic compounds (VOCs) and formaldehyde are two contaminants that pose serious threats to human health and well-being in indoor environments. The varied disinfectant properties of chlorine dioxide (ClO2) make it a key player in treating a range of air quality issues. To balance effectiveness and safety, however, the careful application of chlorine dioxide is essential to achieving the best results in air quality while preserving human health and well-being. This study explores the many functions of chlorine dioxide, including the prevention of the spread of viruses, the elimination of harmful gases like ammonia and hydrogen sulfide, and its effects on formaldehyde and total volatile organic compounds (TVOCs) in indoor environments using BT100. The results indicate a reduction of 98.5%, 81.01%, 62.22%, 46.5%, and 63.84% in minimizing aerosolized viruses, ammonia, and hydrogen sulfide gas in addition to formaldehyde and total volatile organic compounds.

Synthesis, and in vitro evaluation of benzene sulfonamide derivatives for antimicrobial and disinfectant properties: Part-I

The synthesis of benzene sulfonamide derivatives has been reported here for the antimicrobial and disinfectant properties. The synthesis was performed by known literature procedure. P-Toulene sulfonyl chloride was reacted with ethylene diamine to yield to the desired compounds. The synthesis of these agents is reported in part -I of the paper. In subsequent parts the antimicrobial activity and disinfectant properties shall be reported.

Evaluating the antimicrobial properties of natural and combined disinfectants (based on vinegar and rose water) against surface bacteria

Evaluating the antimicrobial properties of natural and combined disinfectants (based on vinegar and rose water) against surface bacteria

Hydroquinine Enhances the Efficacy of Contact Lens Solutions for Inhibiting Pseudomonas aeruginosa Adhesion and Biofilm Formation.

P. aeruginosa is one of the most common bacteria causing contact lens-related microbial keratitis (CLMK). Previous studies report that disinfecting solutions were ineffective in preventing biofilm formation. Solutions containing novel natural agents may be an excellent alternative for reducing the risk of CLMK. Here, we investigate the disinfecting properties of hydroquinine in combination with multipurpose solutions (MPSs) to prevent P. aeruginosa adhesion and biofilm formation. We examined the antibacterial, anti-adhesion, and anti-biofilm properties of hydroquinine-formulated MPSs compared to MPSs alone. Using RT-qPCR, hydroquinine directly affected the expression levels of adhesion-related genes, namely, cgrC, cheY, cheZ, fimU, and pilV, resulting in reduced adhesion and anti-biofilm formation. Using ISO 14729 stand-alone testing, hydroquinine met the criteria (>99.9% killing at disinfection time) against both P. aeruginosa reference and clinical strains. Using the crystal violet retention assay and FE-SEM, MPSs combined with hydroquinine were effective in inhibiting P. aeruginosa adhesion and destroying preexisting biofilms. This report is the first to highlight the potential utility of hydroquinine-containing formulations as a disinfecting solution for contact lenses, specifically for inhibiting adhesion and destroying biofilm. These findings may aid in the development of novel disinfectants aimed at combating P. aeruginosa, thereby potentially reducing the incidence of CLMK.

IMPROVEMENT OF TECHNOLOGICAL STAGES IN BEEKEEPING WITH DISINFECTION MEASURES

Disinfection is a very important technological measure, which is carried out to combat infectious diseases of bees and prevent contamination of beekeeping products with harmful microorganisms. The disinfection procedure is very complex, and its effectiveness depends on a large number of factors: the spectrum of the disinfectant, the method of application, the concentration of the disinfectant, the exposure time, and the properties of the environment to be disinfected. Active components of disinfectants usually affect the metabolism of microorganisms. For disinfection in beekeeping, we can use iodine preparations, bases, acids, quaternary ammonium compounds, oxidizers (hydrogen peroxide, peracetic acid). Effective chemical disinfectants are a warm solution of sodium hydroxide, oxidizers, so these disinfectants are most often used in beekeeping. However, the negative properties of these disinfectants should also be considered. There is no perfect disinfectant. Because of the toxicity and other harmful effects of disinfectants, and often their ineffectiveness, physical methods of disinfection should be implemented whenever possible. The article presents the results of studies of such disinfectants as Septox, PHMG – HC and Crystal-700 in concentrations of 0.25%, 0.5%, 1.5%, as well as a comparative description of their effectiveness during “in vitro” disinfection on test objects (glass, veneer, wax) contaminated with spores of Paenibacillus larvae subsp. larvae and Ascosphaera apis. Test controls were: No. 1 – sterile physiological solution; No. 2 – Desvax (4% formaldehyde solution with 0.05% DMSO), a drug approved for disinfection of bee inventory in Ukraine (Deklaratsiinyi patent 61387A, 2003, Rudenko, 2012). The test objects were immersed in the test solutions and kept for 3, 9, 18 hours. To determine the intestinal toxicity, the test substances were fed to bees and the time and number of dead individuals were monitored. According to the results of the sanitary and hygienic assessment of individual indicators of chemical disinfectants, the best disinfecting properties were demonstrated by 1.5% solutions of polyhexamethyleneguanidine hydrochloride, sodium hypochlorite and Crystal-700, which are environmentally safe, non-toxic, non-volatile, non-aggressive towards metals, plastics, wood, convenient to use. They can be recommended for long-term antiseptic protection, preventive, forced, current and final disinfection for bacterial, fungal and viral infections.

Injectable Methacrylated Gelatin Hydrogel for Safe Sodium Hypochlorite Delivery in Endodontics.

Keeping sodium hypochlorite (NaOCl) within the root canal is challenging in regenerative endodontics. In this study, we developed a drug delivery system using a gelatin methacryloyl (GelMA) hydrogel incorporated with aluminosilicate clay nanotubes (HNTs) loaded with NaOCl. Pure GelMA, pure HNTs, and NaOCl-loaded HNTs carrying varying concentrations were assessed for chemo-mechanical properties, degradability, swelling capacity, cytocompatibility, antimicrobial and antibiofilm activities, and in vivo for inflammatory response and degradation. SEM images revealed consistent pore sizes of 70-80 µm for all samples, irrespective of the HNT and NaOCl concentration, while HNT-loaded hydrogels exhibited rougher surfaces. The hydrogel's compressive modulus remained between 100 and 200 kPa, with no significant variations. All hydrogels demonstrated a 6-7-fold mass increase and complete degradation by the seventh day. Despite an initial decrease in cell viability, all groups recovered to 65-80% compared to the control. Regarding antibacterial and antibiofilm properties, 12.5 HNT(Double) showed the highest inhibition zone on agar plates and the most significant reduction in biofilm compared to other groups. In vivo, the 12.5 HNT(Double) group displayed partial degradation after 21 days, with mild localized inflammatory responses but no tissue necrosis. In conclusion, the HNT-NaOCl-loaded GelMA hydrogel retains the disinfectant properties, providing a safer option for endodontic procedures without harmful potential.

Insights into a Removal Mechanism of Triclosan Using an Electroactivated Persulfate-Coupled Carbon Membrane System

Triclosan (TCS), a broad-spectrum bacteriostatic agent with bactericidal and disinfectant properties, is one of the emerging pollutants of great interest. The electrically activated persulfate-coupled carbon membrane system was studied in this paper. The removal of triclosan achieved 90% within 40 min. Complete degradation can be achieved within 90 min. The electrode was characterized by scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The optimal reaction conditions were explored. The catalytic mechanism of the reaction was investigated. It was proved that hydroxyl radicals, sulfate radicals, and singlet oxygen were the main reactive oxygen species in the reaction process by the free radical quenching experiment and electron paramagnetic resonance spectrometer. The degradation path and mechanism of triclosan were investigated.

Biocompatible Alginate Hydrogel Film Containing Acetic Acid Manifests Broad-Spectrum Antiviral and Anticancer Activities.

Acetic acid, a colourless liquid organic acid with a characteristic acrid smell, is obtained naturally and has applications in both the food and pharmaceutical industries. It has been reported to have beneficial uses for lifestyle-related diseases, and its efficient disinfectant properties are well known. In this study, an alginate crosslinked with Ca2+ hydrogel film was treated with acetic acid to explore its biological properties for biomedicine. The results showed that the novel calcium alginate/acetic acid film was biocompatible in vitro using human keratinocyte cells and in vivo with Caenorhabditis elegans. It also had antiviral properties against enveloped and non-enveloped viruses and anticancer properties against melanoma and colon cancer cells. This novel film thus showed promise for the biomedical and pharmaceutical industries, with applications for fabricating broad-spectrum antiviral and anticancer materials.

A rare incident of intraoral formalin injection

Formalin is a hazardous chemical that needs careful handling and special storage. It is generally used in dentistry because of its disinfectant and fixative properties. Negligence on part of the dental professionals by accidentally injecting formalin rather than the original anesthetic can lead to internal tissue damage and also may induce a life threatening situation. The general practice of storing formalin in the original anesthetic bottles and being supported by untrained assistants is the most common reason for this mishap to happen. The operating dentist should be careful and apprehensive of the medicines and chemicals available in the operatory and re-check the solution being injected in the case as to not land up in complications because of the negligence. Successful management can be done by cautious debridement and empirical medicine therapy.

Modulation of toxicity effects of CuSO4 by sulfated polysaccharides extracted from brown algae (Sargassum tenerrimum) in Danio rerio as a model

Copper is widely used in agriculture and aquaculture due to its high disinfection properties and relatively low cost. However, the increase in copper concentration due to evaporation can lead to water reservoir pollution, which can harm the health of consumers. The present study aimed to determine the role of sulfated polysaccharides (SPs) extracted from Sargassum tenerimum algae in reducing lesions caused by the heavy metal copper. Zebrafish (Danio rerio) were used as a human model in five treatments. The negative and positive control groups were fed a diet containing zero percent of SPs, while the experimental groups were fed 0.5%, 1%, and 1.5% of SPs in three treatments for 56 days, finally CuSO4 was exposed only to the positive control group and the groups fed with SPs. Results showed a significant decrease in the activity level of ALT enzymes (39–16 U/mL), AST (67–46 U/mL), and ALP (485–237 U/mL), confirming the results obtained from histopathological studies in CuSO4 exposed groups. The addition of SPs to the diet resulted in a significant reduction (sig < 0.05) of mortalities due to the decrease of tissue damage. Additionally, due to the anti-inflammatory properties and the protective effect of SPs, a significant decrease (sig < 0.05) was observed in the relative expression of Il-1β and Tnf-α genes.

Biobased Natural Sapindus mukorossi–Carvacrol Emulsion for Sustainable Laundry Washing

Low-temperature laundry washing prompted the formulation of a new biobased detergent that meets sustainability criteria. A soapnut extract conferred good cleaning performance on the standard soiling agents EMPA 101 and EMPA 114 but showed rather weak performance on EMPA 116 and EMPA 160. The results indicated the good disinfection properties of the soapnut extract–Carvacrol emulsion (&gt;6 log CFU/carriers), whereas the commercial detergent and sole soapnut extract were less effective. Comparable results were observed for cross-contamination assessment and wash water, whereas total elimination was achieved only for the soapnut extract–Carvacrol emulsion. We demonstrated significantly decreased water surface tension for all three compounds. The microorganism cell membrane integrity assessment showed the highest number of dead cells on cotton carriers washed with the soapnut extract–Carvacrol emulsion. All this indicated that the newly formulated biobased laundry detergent made of soapnut extract and Carvacrol could effectively remove standard soiling agents and ensure good disinfection.

Disinfection of Digestate Effluents Using Photocatalytic Nanofiltration

The disinfection properties of photocatalysis on liquid digestate derived from biogas plants have been investigated for the first time. The study presents the physiological characteristics of liquid digestate retrieved from various biogas plants based in northern Greece, revealing the heterogeneity of this matrix. Preliminary photocatalysis experiments conducted on inoculated liquid digestate samples showed that disinfection was possible when a pre-treated digestate underwent a combination of centrifuge–flocculation–μfiltration after 5.5 h with 0.7 g/L suspended TiO2 under UVA illumination. To explore the feasibility of an industrial application based on this concept, a novel design photocatalytic nanofiltration reactor was implemented for disinfection experiments on pre-treated liquid digestate. The synergistic action of photocatalysis during nanofiltration alleviated the leakage phenomena, and both the retentate and permeate effluents had lower concentrations of pathogens by approximately 1–2 log10 cfu/mL. This work sets out the basis for the efficient operation and engineering application of collaborative technology, with photocatalysis as the final step for liquid digestate sanitation and reusable water recovery.

Determination of fungicidal effect of disinfectant ‘SanDezVet’ on sanitary significant test cultures of mold micromycetes of the genus Aspergillus Mich.

Studying the properties of new disinfectants is a crucial aspect of disinfectology research. During the investigation of the fungicidal properties of the ‘SanDezVet’ disinfectant, it was discovered that the recommended concentrations of 0.1% and 0.5%, at a temperature of 20.0 ± 0.5 °C and an exposure time of 60, 120, and 180 minutes, do not inhibit the growth of Aspergillus fumigatus, Aspergillus flavus, and Aspergillus niger test cultures. This conclusion was reached as continuous growth of micromycetes was observed in all drug dilutions. The disinfectant ‘SanDezVet’ at a concentration of 3.0% displayed fungistatic properties by significantly delaying the growth of experimental test cultures. A 5.0% solution of the disinfectant resulted in a complete delay in growth of museum strains of Aspergillus fumigatus, Aspergillus flavus, and Aspergillus niger. This indicates fungicidal properties when compared to the positive control. Based on the obtained results, it was observed that the optimal exposure times for disinfection measures with ‘SanDezVet’ are 60 and 120 minutes. ‘SanDezVet’ can be effectively used for fungal infections at different veterinary facilities

UV Sterilization Biological Safety Cabinet

Abstract: In the past three years COVID-19 has been a major health concern. The World Health (WHO) Organization declared COVID-19 as a pandemic and WHO said that the chances of more pandemics happening in near future are very high. To avoid such pandemics basic safety measures, have to be taken seriously such as sanitization and sterilization. COVID-19 was identified to be transmitting through various mediums such as currencies, cards, daily household objects, medical supplies and etc. Things like PPE kit, surgical masks and N95 respirators are crucially important for the safety of patient and medical personnel working during the pandemic. Due to the pandemic the demandof safety kits outnumbered the supply and medical professionals were left to use the already used PPEkits. The primary goal of the Biological Safety Cabinet(BSC) is to sterilize things like medical equipment anddaily use objects. Ultraviolet (UV) light is used for the purpose of disinfection or sterilization of rooms and surfaces. UV-C has germicidal properties but it is also harmful for human beings. Hence, for the purpose of sterilization without human interference, a UV BSC has been designed to sterilize daily use objects and medical essentials.

Dissemination of a “Fake Miracle Cure” against COVID-19 on Twitter: The Case of Chlorine Dioxide

The COVID-19 pandemic has given rise to all types of beliefs, theories, and explanations, whether scientific, religious, or conspiratorial. At the beginning of the pandemic, science did not yet have a medicinal product for this new disease, and alternative medicines offering “miracle cures” were acclaimed by some citizens looking for an effective treatment for COVID-19. This article aims to study a specific “miracle cure”, namely, chlorine dioxide, a bleaching agent for textiles or paper that also has disinfectant properties (water, surfaces). The dissemination of information about chlorine dioxide to French-speaking people on the social network Twitter from 1 December 2019 to 30 November 2021 is analyzed using a graph network. The results show that messages promoting misinformation, even if they are likely to be quantitatively less numerous, spread more widely than those based on more reliable information. In addition, this article shows that chlorine dioxide was promoted as an effective cure by medical doctors and peer-reviewed articles, which consequently increased the dissemination of this belief in the social space. Consequently, the process of misinformation entered the sphere of scientific controversy. The boundary between science and misinformation is becoming blurred to the point that it is no longer possible until proven otherwise to call chlorine dioxide a “false miracle cure” but a controversial treatment against COVID-19.

Efficacy of a filtered far-UVC handheld disinfection device in reducing the microbial bioburden of hospital surfaces

The filtered far-UV-C (FFUV) handheld disinfection device is a small portable device that emits far UV-C at 222nm. The objective of this study was to evaluate the device's ability to kill microbial pathogens on hospital surfaces and compare it to manual disinfection using germicidal sodium hypochlorite wipes. A total of 344 observations (4 observations from 86 objects' surfaces) were sampled with 2 paired samples per surface: a pre- and a post-sodium hypochlorite and FFUV sample. The results were analyzed via a Bayesian multilevel negative binomial regression model. The estimated mean colony counts for the sodium hypochlorite control and treatment groups were 20.5 (95% uncertainty interval:11.7-36.0) and 0.1 (0.0-0.2) colony forming units (CFUs), respectively. The FFUV control and treatment groups had mean colony counts of 22.2 (12.5-40.1) and 4.1 (2.3-7.2) CFUs. The sodium hypochlorite group and the FFUV group had an estimated 99.4% (99.0%-99.7%) and 81.4% (76.2%-85.7%) reduction in colony counts, respectively. The FFUV handheld device effectively reduced the microbial bioburden on surfaces in the health care setting. The major benefit of FFUV is likely seen when manual disinfection is not possible or when supplementing cleaners or disinfectants with the low-level disinfection properties.