Antimicrobial substances are substances that have the ability to kill or slow down the growth of microorganisms such as bacteria,algae and fungi.Exposure of microorganisms to low concentrations of antimicrobial substa...Antimicrobial substances are substances that have the ability to kill or slow down the growth of microorganisms such as bacteria,algae and fungi.Exposure of microorganisms to low concentrations of antimicrobial substances may lead to the development of antimicrobial resistance.To protect human health and the environment and to limit resistance,the risks for the release of these substances into the environment should be minimized from all sources.Under the current EU legal framework,some specific uses of antimicrobial substances are strictly regulated whereas others are not.When antimicrobial substances are used as active substances in biocidal products,such as disinfectants,they are regulated by Biocidal Products Regulation.When the same substances are used as preservatives in cosmetic products they fall under Cosmetic Products Regulation.In this paper,we investigated how the regulation of antimicrobial substances differ when used in biocidal products compared to cosmetic products.This was achieved by performing a systematic comparison using document analysis with focus on aims,scope,information requirements,and risk assessment procedures for biocidal active substances and cosmetic preservatives.One of the main differences identified is that no environmental data or environmental risk assessment are required for approval of cosmetic preservatives.In contrast,environmental data and risk assessment for both the active substances and one representative product would be required for the approval of the same substance if used as a biocidal active substance.This means first that a substance not approved for use in biocidal products due to its hazardous environmental properties can still be approved as a cosmetic preservative.And second,the environmental release of antimicrobial substances from cosmetic products remains unassessed and uncontrolled,despite the obvious risks of cosmetic ingredients being emitted into the environment via wastewater.From this,we recommend that an environmental risk assessment is added to the requirements for market approval of cosmetic preservatives to achieve the aim of a high level of protection for the environment as set by several EU regulations.This would be in line with the“one substance e one assessment”approach proposed by the European Commission.While the details of“one substance e one assessment”approach are not decided,it is believed to contribute to more coordinated and transparent chemical safety assessments and enhance interlinking between the regulations.展开更多
We have investigated the mode of action of synthetic biocides,(2-(thiocyanomethylthio)benzothiazole(TCMTB),dichlorophen,(commonly used in leather industry for preservation)and natural biocides,oregano and eucalyptus o...We have investigated the mode of action of synthetic biocides,(2-(thiocyanomethylthio)benzothiazole(TCMTB),dichlorophen,(commonly used in leather industry for preservation)and natural biocides,oregano and eucalyptus oils,on Aeromonas hydrophila using Raman spectroscopy in collaboration with multivariate analysis and 2D correlation spectroscopy to evaluate whether Raman spectra acquired contained valuable information to study the action of biocides on bacterial cells.The growth of A.hydrophila in clear and outer edge zone of inhibition differ in their reaction with different biocides,which allows us to highlight the differences as a characteristic of two kinds of bacteria.Such classification helps identify oregano oil as the most effective biocide by altering clear and outer edge zone of bacteria.Standard disk diffusion assay method was used for screening biocide bacteria interactions and later analysed by Raman spectroscopy.The paper also presents the introduction of TCMTB and oregano oil into leather processing stages to examine and determine the antimicrobial effect as an application to real-world setting.Therefore,we conclude that Raman spectroscopy with appropriate computational tools constitutes a powerful approach for screening biocides,which provide solutions to all the industries using biocides including leather industry,considering the potentially harmful effect of biocides to humans and the environment.展开更多
Organic biocides as timber preservatives have aroused more and more attention,because metal salts especially arsenic,chrome and so on, have been suspected to be poisonous to the soil and aquatic animals,as well as the...Organic biocides as timber preservatives have aroused more and more attention,because metal salts especially arsenic,chrome and so on, have been suspected to be poisonous to the soil and aquatic animals,as well as the disposal of preserved timber wastes.Therefore,a number of effective organic biocides have been selected to prevent wood or bamboo from decay,mildew, stain and so on.Most of these products have entered into the market.With people’s increasing awareness of the environmental protection,organic biocides will eventually play important roles in timber preservation in the future.This paper summarized the studies on application of organic biocides as wood or bamboo preservatives,including resistant mechanisms,commonly applied types and effects against wood or bamboo fungi,approaches to detecting the amount of organic biocides in timber and their influences on the environment.Based on the discussion above,the authors predicted the developing prospect of organic biocides in timber preservation.展开更多
Nanoparticles have been used as diagnostic and therapeutic agents in the human medical field for quite some time, though their application in veterinary medicine and animal production is still relatively new. Recently...Nanoparticles have been used as diagnostic and therapeutic agents in the human medical field for quite some time, though their application in veterinary medicine and animal production is still relatively new. Recently,production demands on the livestock industry have been centered around the use of antibiotics as growth promoters due to growing concern over microbial antibiotic resistance. With many countries reporting increased incidences of antibiotic-resistant bacteria, laws and regulations are being updated to end in-feed antibiotic use in the animal production industry. This sets the need for suitable alternatives to be established for inclusion in feed.Many reports have shown evidence that nanoparticles may be good candidates for animal growth promotion and antimicrobials. The current status and advancements of nanotechnological applications in animal production will be the focus of this review and the emerging roles of nanoparticles for nutrient delivery, biocidal agents, and tools in veterinary medicine and reproduction will be discussed. Additionally, influences on meat, egg, and milk quality will be reviewed.展开更多
The use of seawater for industrial cooling is a vital technology that poses some of the most profound environmental impact on the water quality in the Arabian Gulf. Biocide (chlorine) is added to the seawater to contr...The use of seawater for industrial cooling is a vital technology that poses some of the most profound environmental impact on the water quality in the Arabian Gulf. Biocide (chlorine) is added to the seawater to control biofouling of the cooling system. This added chlorine reacts with bromide and other chemicals naturally exist in the water to form a wide range of oxidants. Regrettably, reactions between the residual oxidants and natural organic matter in the water lead to formation of toxic halogenated organic compounds that have detrimental effects on the environment when they are discharged into the Gulf. This paper describes the formation of trihalomethanes (THMs) in seawater cooling systems. Results of kinetic experiments have shown that concentrations of THMs increased rapidly with time during the first half hour. Chlorination of seawater has shown significant increase in total THMs (TTHMs) and in bromoform concentrations. Rapid decrease of UV absorbance at 254 nm was also observed during seawater chlorination which is indicative of natural organic matter degradation into small organic molecules including THMs and other by-products. The increase in chlorine dose was accompanied with an increase in TTHMs and bromoform concentrations. Linear relationships between total chlorine concentration and both final TTHMs and bromoform concentrations were established. First order exponential decay and exponential associate functions were developed to correlate chlorine dose with formed THMs.展开更多
The science and technology interact with the art in several ways. Biotechnological coupled with analytical approaches can play an important role in protecting and preserving cultural heritage for future generations. M...The science and technology interact with the art in several ways. Biotechnological coupled with analytical approaches can play an important role in protecting and preserving cultural heritage for future generations. Many microorganisms influenced by environmental conditions are the main responsible for biological contamination in built heritage. Biocides based on chemical compounds have been used to mitigate this problem. Thus, it is vitally important to develop proper remediation actions based on environmentally innocuous alternative. Bacillus specie is emerging as an optimistic alternative for built heritage treatment due to their capacity to produce secondary metabolites with antagonistic activities against many fungal pathogens. Therefore, the intent of this work was to access a rapid evaluation of antifungal potential of bioactive metabolites produced by Bacillus strains and simultaneously their characterization using spectroscopic (NMR) and chromatographic techniques (LC-ESI-MS). The high antifungal activity obtained for Bacillus sp. active compounds produced in this study confirms the great potential to suppress biodeteriogenic fungi growth on historical artworks. Additionally, the proposed methodology allowed to access bioactive metabolites produced without need of the laborious total previous isolation and could be used as a viable alternative to be employed for screening and production of new green biocides.展开更多
Seawater desalination is one of the major industrial activities along the coastline of Kuwait that poses profound environmental impact on the quality of seawater.This study focuses on investigating the potential conta...Seawater desalination is one of the major industrial activities along the coastline of Kuwait that poses profound environmental impact on the quality of seawater.This study focuses on investigating the potential contamination of biocides,volatile organic hydrocarbons(VOCs)and other halogenated hydrocarbons discharged from Az-Zour desalination plant.Chemical contamination by residual chlorine(RC)and some VOCs was detected in effluents from inside and at the vicinity of the plant.RC ranged between 0.15 and 0.49 mg/L while bromoform(CHBr3)was the highest of all the VOCs detected and ranged between 0.22 and 3.30μg/L.Benzinoides(benzene,toluene,xylene and ethylbenzene)were also detected at 0.1μg/L and 0.25μg/L.The levels of RC as measured in the vicinity of the Az-Zour plant are below the limit set up by Kuwait EPA.However,it still poses effects to the nearby aquatic life and therefore,it is important to lower the concentration of RC in the discharge effluent.展开更多
Background: Annonaceous acetogenins enclose a large number of biological activities, among which the insecticidal stands out. Methods: We report herein the biocide effects of natural acetogenins from Annona squamosa, ...Background: Annonaceous acetogenins enclose a large number of biological activities, among which the insecticidal stands out. Methods: We report herein the biocide effects of natural acetogenins from Annona squamosa, A.?muricata and A. montana seeds: annonacin, cis-annonacin, cis-annonacin-10- one, asimicin, rolliniastatin-2, cherimolin-1, cherimolin-2, almuñequin, and two β-OH acetogenins: laherradurin and itrabin on Spodoptera frugiperda Smith (Lepidoptera: Noctuidae). Also, some acetylated and methoxy methylated ACG derivatives were synthesized and evaluated: annonacin (3 OAc), annonacin (4 OAc), asimicin (3 OAc), rolliniastatin-2 (3 OAc), rolliniastatin-2 (MOM), laherradurin (3 OAc) and itrabin (3 OAc). Results: The natural acetogenin rolliniastatin-2 (100 μg·g-1 of diet) produced the most important toxic action causing 100% mortality of early instar larvae. Derivatization of ACG yielded compounds that produced nutritional alterations. The incorporation of rolliniastatin-2 (3 OAc) and rolliniastatin-2 (3 MOM) (100 μg·g-1) into the artificial diet of Spodoptera frugiperdadisplayed the strongest antifeedant effects causing marked decreasings in larval growth and adult lethal malformations. Conclusion: Natural acetogenins are promising metabolites for insect control. Derivatization of these compounds reduces their toxicity to early instar larvae.展开更多
Annonaceous acetogenins enclose a large number of biological activities, among which the insecticidal stands out. <em>Spodoptera frugiperda</em> is a pest that affects corn crops among others and has a gre...Annonaceous acetogenins enclose a large number of biological activities, among which the insecticidal stands out. <em>Spodoptera frugiperda</em> is a pest that affects corn crops among others and has a great capacity to develop resistance to traditional insecticides, which represents sufficient reasons for the search for new alternatives for their control. The objective of this study was to determine the appropriate concentration and screening new natural insecticides against second instar larvae of <em>S. frugiperda</em>, under glasshouse conditions on <em>Zea mays</em> L. Natural products such as annonaceous acetogenins and some acetylated and methoxy methylated ACG derivatives and the commercial product Lambda-cyhalotrin (LC) were evaluated. The percent mortalities of <em>S. frugiperda </em>larvae in glasshouse conditions were recorded after 24, 48 and 72 h of treatment application. The results showed that the acetogenins tested were significantly (P < 0.05) different in relation to pest mortality than untreated check. After 72 h of treatment application the highest percent mortalities were obtained with the mixture of two natural products, rolliniastatin-2 (<strong>5</strong>) (100 μg/mL) + squamocin (<strong>6</strong>) (100 μg/mL) + LC (50 μg/mL) that proved the most effective and gave (100%), while rolliniastatin-2 (<strong>5</strong>) at 100 μg/mL alone, gave lowest percent mortality (65%), followed by squamocin (<strong>6</strong>) at 100 μg/mL (55%) and LC at 50 μg/mL (30%). The acetylated and methoxy methylated ACGs derivatives caused very low mortality (25% - 35%). It is recommended the mixture as a management option of <em>S. frugiperda</em> as a component of integrated pest management. The results allow us to infer that the addition of natural ACGs synergizes the insecticidal activity of the commercial product. Finding a new ecological alternative for insect control.展开更多
Emulsive polymerization of mono- and dy(meth)acrylates of butandiol, decid(meth)acrylate, methyl-α-alkilacrylates with industrial acrylic monomers—butylacrylate, methylacrylate, methacrylic acid, methyl(meth)acrylat...Emulsive polymerization of mono- and dy(meth)acrylates of butandiol, decid(meth)acrylate, methyl-α-alkilacrylates with industrial acrylic monomers—butylacrylate, methylacrylate, methacrylic acid, methyl(meth)acrylate has been investigated. Structurization of copolymers using dy(meth)acrylates of butandiol, braking of emulsive polymerization using water insoluble biocides, dy(meth)acrylates of butandiol and methyl-α-alkilacrylates have been determined. The mechanism of emulsive polymerization of (meth)acrylic monomers using methyl-α-alkilacrylates has been investigated.展开更多
Objective:To evaluate in vitro effects of Tagetes minuta L. essential oil(TEO) on L3 Anisakis larvae type 1. Methods:In order to evaluate the potential use of Tagetes minuta essential oil against L3 Anisakis larvae th...Objective:To evaluate in vitro effects of Tagetes minuta L. essential oil(TEO) on L3 Anisakis larvae type 1. Methods:In order to evaluate the potential use of Tagetes minuta essential oil against L3 Anisakis larvae three different media were tested:1) a saline solution(SS); 2) an industrial marinating solution; 3) sunflower seeds oil(SO). For each media and concentrations of TEO(0.1%,0.5%,1.0% and 5.0% v/v),20 parasites were introduced into plastic Petri dishes(diameter 90 mm) and maintained at room temperature. As controls,larvae were maintained without TEO under identical experimental conditions in SS,MS and SO. A total of 900 larvae were tested. The normalized mean viability,LT100,LT50 and the percentage of inactivation at 24 hours were calculated. Results:In vitro tests revealed a complete inactivation of parasites in saline solution after 2 hours with 5% and 1% of TEO. In marinating solution,a complete inactivation of parasites was observed after 4 hours at all concentrations used. A slower activity for all TEO concentration was reported in SO. Conclusions:The results obtained,showing a strong activity against Anisakis larvae,confirm TEO as a larvicidal agent in the treatment of human anisakidosis and in the industrial marinating process.展开更多
Silver Nanoparticles were synthesized by Esche- richia coli using Silver nitrate in the growth me-dium and characterized in X-Ray Diffraction, UV-Vis Spectrophotometer and Scanning Electron Microscope. They exhibited ...Silver Nanoparticles were synthesized by Esche- richia coli using Silver nitrate in the growth me-dium and characterized in X-Ray Diffraction, UV-Vis Spectrophotometer and Scanning Electron Microscope. They exhibited antimicrobial activity against human pathogens except Escherichia Coli. Nanoparticles were impregnated in yarn and ana-lyzed for their inhibition in the broth culture. The Minimal Inhibitory Concentratio was calculated for the human pathogens in Microtitre plate. The toxicity assessment of the nanoparticles in the embry-onic Zebrafish showed many organogensis deformi-ties like cardiac malformations, eye and head edema, tail and trunk flexure were observed in the organ system of the developing embryos for 1 to 5 day post fertilization in different concentrations of Ag Nanoparticles. The Organogenesis disruptive effects were found in 14 - 20 ng/ml of silver nanoparticles but the inhibition was found in 4-10ng/ml for the pathogens in vitro and 10ng/ml in embryos. Nevertheless, in Cardiac assay, the Heart Beat rates were calculated as 42 - 45 for 15 Sec in the concentrations ranging from 10 - 20 ng/ml of Silver nanoparticles. The blood flows, rhythmicity, contractility of heart beat rates were observed normal. The Mean value of blood Cell counting did not showed any notable effects in the Nanoparticle treated Zebrafish embryos and control. The LC50 value for the Biosynthesized nanoparticle was at 22 ng/ml in all the developmental stages of the em-bryos. Our results shows silver nanoparticles dis-rupts the normal organogenesis during development and further detailed studies are needed to prove silver nanopartcles are an antimicrobial agent for use in humans.展开更多
Toxic pollutants are metabolic poisons that can seriously injure or destroy the photosynthetic organisms upon which the food chain depends. Since microalgae play a key role in marine ecosystems, marine microalgae are ...Toxic pollutants are metabolic poisons that can seriously injure or destroy the photosynthetic organisms upon which the food chain depends. Since microalgae play a key role in marine ecosystems, marine microalgae are proposed as excellent bio-indicators of pollution due to their high sensitivity, which can give warning of the toxic effects of chemicals sooner than any other species. The aim of this work concentrated on the effect of different concentrations of the antifouling biocide (Irgarol 1051) on growth and chlorophylls content (as an essential metabolite) of the two marine unicellular green algae Chlorella salina and Dunaliella bardawil that usually used in fish feeding. The growth of the wall-less Dunaliella bardawil was more sensitive to Irgarol 1051 than the walled cells Chlorella salina, although the concentrations used were greatly different. The product of photosynthesis in the two algal species greatly affected since in the presence of Irgarol 1051, a serious destructive effect was observed. The cell wall appeared to play a significant role in protecting the organism against toxicity of the antifouling agent either by adsorption or degradation. The strength of toxicity depends mainly on the concentration of the antifouling agent, the length of culturing period and the type of organism tested.展开更多
Ferrocyanides of Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) were synthesized and characterized by IR spectra, magnetic susceptibility, thermal gravimetric analysis, elemental analysis and X ray diffraction studies. Ant...Ferrocyanides of Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) were synthesized and characterized by IR spectra, magnetic susceptibility, thermal gravimetric analysis, elemental analysis and X ray diffraction studies. Antimicrobial potential of these complexes have been evaluated. Antifungal screening of these complexes has been carried out against Mycogone perniciosa and Verticillium fungicola causing wet and dry bubble diseases of button mushroom respectively. Nickel ferrocyanide has been found to be most effective against Mycogone perniciosa with 60% inhibitory effect while cadmium ferrocyanide has exhibited significant potential of 85% against Verticillium fungicola.展开更多
In this research we decided to analyze the addition of silver(Ag°)on zinc oxide(ZnO)utilizing two nanoparticles:the synthesized zinc oxide-doped-silver nanoparticles(ZnO/Ag_Lab)utilizing the zinc nitrate as metal...In this research we decided to analyze the addition of silver(Ag°)on zinc oxide(ZnO)utilizing two nanoparticles:the synthesized zinc oxide-doped-silver nanoparticles(ZnO/Ag_Lab)utilizing the zinc nitrate as metal precursor for ZnO and silver nitrate as metal precursor for Ag°;and the commercial nanoparticle ZnO/Ag.For the study of application of the nanoparticles,they were processed in the form of films and the polymer utilized was the blend of HMSPP(high melt strength polypropylene)and styrene-ethylene/butadiene-styrene.For the study of nanoparticles,they were submitted to biocide tests against Staphylococcus aureus(ATCC 6538)and Escherichia coli(ATCC8739)and XRD(X-Ray Diffraction).The XRD analysis results indicated,in both of nanoparticles,with the presence of wurtzite phase of ZnO,being that on the commercial nanoparticles the intensity of peak was higher than that of synthesized one,on other hand,the peaks attributed to Ag°,were more intense in the synthesized nanoparticle.展开更多
Wood can be a suitable alternative to energy-intensive materials in various applications.Nev-ertheless,its susceptibility to weathering and decay has significantly hindered the broad adop-tion of the most commercially...Wood can be a suitable alternative to energy-intensive materials in various applications.Nev-ertheless,its susceptibility to weathering and decay has significantly hindered the broad adop-tion of the most commercially significant wood species.While current solutions do tackle certain challenges,they often come with disadvantages like high costs,environmental risks,and/or in-efficiencies.Nanotechnology-based methods can be employed to mitigate these weaknesses and create durable,sustainable wood materials.In this review,we delve into cutting-edge advance-ments in the development of biodeterioration-resistant wood through innovative nanotechnol-ogy approaches.These methods usually involve the application of nanomaterials,either pos-sessing biocidal properties or serving as carriers for biocides.We systematically describe these approaches and compare them to conventional wood modification methods.Additionally,this re-view provides a brief overview of the prevalent biodeteriorating organisms and their mechanisms of action,which notably impact the development and choice of a suitable strategy for wood mod-ification/treatment.Given the requirements of biodeteriorating organisms for growth and wood degradation,it is expected that the new nanotechnology-based approaches to enhance wood dura-bility may provide innovative broad-spectrum biocidal nanosystems.These systems can simulta-neously induce alterations in the physicochemical properties of wood,thereby constraining the availability of the growth requirements.These alterations can efficiently inhibit the biodeterio-ration process by decreasing water absorption,restricting access to the wood components,and reducing void spaces within the wood structure.Finally,this review highlights the new oppor-tunities,challenges,and perspectives of nanotechnology methods for biodeterioration-resistant wood,through which some techno-economic,environmental and safety aspects associated with these methods are addressed.展开更多
The exposure patterns of pest control and disinfection workers have changed after the coronavirus disease 2019(COVID-19)outbreak,but the health risks of chemical exposure have not been assessed.We identified these wor...The exposure patterns of pest control and disinfection workers have changed after the coronavirus disease 2019(COVID-19)outbreak,but the health risks of chemical exposure have not been assessed.We identified these workers’chemical exposure patterns and risks before and after the COVID-19 outbreak.We used data conducted between 2018(pre-pandemic)and 2021(post-pandemic)from three-year cross-sectional surveys on pest control and disinfection workers.Inhalation and dermal exposure concentrations were estimated using equations based on a biocidal product risk assessment model from the Korean National Institute of Environmental Research.The non-carcinogenic and carcinogenic risks of chemicals were calculated using the United States Environmental Protection Agency risk assessment model.We found that the annual work frequency(50^(th)percentile)of foggers using disinfectants increased the most among all the work types,from 140 uses/year to 176 uses/year after the COVID-19 outbreak.Moreover,all chemicals’non-carcinogenic and carcinogenic risks increased regardless of exposure routes.In the worst scenario(95^(th)percentile),the margin of exposure for citric acid,benzethonium chloride,benzyl-C12-16-alkyldimethyl chlorides,and sodium chlorite of inhalation exposure,and isopropyl alcohol and benzyl-C12-16-alkyldimethyl chlorides of dermal exposure were acceptable(>100)before the COVID-19outbreak but became unacceptable(<100)after the COVID-19 outbreak.Carcinogenic risks of dichlorvos from inhalation and dermal exposure were above acceptable levels(>10^(-6))before and after the COVID-19 outbreak but comparatively high after the COVID-19 outbreak.Additionally,significantly more workers experienced health symptoms after the COVID-19outbreak(p<0.05),with the most common being muscle lethargy(31%),skin/face stinging(28.7%),and breath shortness/neck pain(24.1%).展开更多
Attachment of bacteria and subsequent formation of biofilms on material surfaces lead to serious consequences including infection,contamination and biofouling,posing a prominent threat to human health and causing prob...Attachment of bacteria and subsequent formation of biofilms on material surfaces lead to serious consequences including infection,contamination and biofouling,posing a prominent threat to human health and causing problems in many industries.Therefore,it is highly desirable to endow the surfaces with antibacterial properties.Traditional antibacterial surfaces are designed via either bacteria-resisting strategy to prevent the initial adhesion of bacteria or bacteria-killing strategy to eradicate any bacteria that attach to the surface.However,these single-function surfaces have their inherent shortcomings and cannot realize long-term efficacy against bacteria.In recent years,various dual-function antibacterial surfaces with both bacteria-resisting and bacteria-killing properties together have been developed,showing better performance for combating surface-attached bacteria and preventing formation of biofilms.In this review,we summarize the recent development of these dual-function antibacterial surfaces.We focus on the design principles and fabrication strategies of such surfaces and highlight the representative examples,which are categorized specifically into two types according to the anti-adhesive and bactericidal properties are simultaneous or switchable.A brief perspective is finally presented on current challenges and future research directions.展开更多
The corrosion damage of 20 SiMn steel by sulphate-reducing bacteria(SRB)and the mitigation effect of organic silicon quaternary ammonium salt(OSA)were studied in sterilized mild alkaline simulated concrete pore soluti...The corrosion damage of 20 SiMn steel by sulphate-reducing bacteria(SRB)and the mitigation effect of organic silicon quaternary ammonium salt(OSA)were studied in sterilized mild alkaline simulated concrete pore solution(STR)with different additions of SRB and OSA at pH 9.35 for 28 days.Uniform corrosion occurs in STR medium while slight localized corrosion is observed in STR+OSA medium,and localized pitting corrosion occurs in STR+SRB and STR+SRB+OSA media.The largest pit depth reduces from 36.70μm in STR+SRB medium to 3.31μm in STR+SRB+OSA medium due to the mitigation effect of OSA.The corrosion rate reflected by weight loss and electrochemical impedance spectroscopy(EIS)results presents the order of STR<STR+OSA<STR+SRB+OSA<STR+SRB,which also proves that the presence of SRB can accelerate corrosion in a carbonated medium.However,OSA as an efficient bacteriostatic agent can reduce the excessive growth of SRB and thus reduce corrosion.展开更多
文摘Antimicrobial substances are substances that have the ability to kill or slow down the growth of microorganisms such as bacteria,algae and fungi.Exposure of microorganisms to low concentrations of antimicrobial substances may lead to the development of antimicrobial resistance.To protect human health and the environment and to limit resistance,the risks for the release of these substances into the environment should be minimized from all sources.Under the current EU legal framework,some specific uses of antimicrobial substances are strictly regulated whereas others are not.When antimicrobial substances are used as active substances in biocidal products,such as disinfectants,they are regulated by Biocidal Products Regulation.When the same substances are used as preservatives in cosmetic products they fall under Cosmetic Products Regulation.In this paper,we investigated how the regulation of antimicrobial substances differ when used in biocidal products compared to cosmetic products.This was achieved by performing a systematic comparison using document analysis with focus on aims,scope,information requirements,and risk assessment procedures for biocidal active substances and cosmetic preservatives.One of the main differences identified is that no environmental data or environmental risk assessment are required for approval of cosmetic preservatives.In contrast,environmental data and risk assessment for both the active substances and one representative product would be required for the approval of the same substance if used as a biocidal active substance.This means first that a substance not approved for use in biocidal products due to its hazardous environmental properties can still be approved as a cosmetic preservative.And second,the environmental release of antimicrobial substances from cosmetic products remains unassessed and uncontrolled,despite the obvious risks of cosmetic ingredients being emitted into the environment via wastewater.From this,we recommend that an environmental risk assessment is added to the requirements for market approval of cosmetic preservatives to achieve the aim of a high level of protection for the environment as set by several EU regulations.This would be in line with the“one substance e one assessment”approach proposed by the European Commission.While the details of“one substance e one assessment”approach are not decided,it is believed to contribute to more coordinated and transparent chemical safety assessments and enhance interlinking between the regulations.
基金The research is funded by the Ministry of Business,Innovation and Employment(MBIE)grant number LSRX1801.
文摘We have investigated the mode of action of synthetic biocides,(2-(thiocyanomethylthio)benzothiazole(TCMTB),dichlorophen,(commonly used in leather industry for preservation)and natural biocides,oregano and eucalyptus oils,on Aeromonas hydrophila using Raman spectroscopy in collaboration with multivariate analysis and 2D correlation spectroscopy to evaluate whether Raman spectra acquired contained valuable information to study the action of biocides on bacterial cells.The growth of A.hydrophila in clear and outer edge zone of inhibition differ in their reaction with different biocides,which allows us to highlight the differences as a characteristic of two kinds of bacteria.Such classification helps identify oregano oil as the most effective biocide by altering clear and outer edge zone of bacteria.Standard disk diffusion assay method was used for screening biocide bacteria interactions and later analysed by Raman spectroscopy.The paper also presents the introduction of TCMTB and oregano oil into leather processing stages to examine and determine the antimicrobial effect as an application to real-world setting.Therefore,we conclude that Raman spectroscopy with appropriate computational tools constitutes a powerful approach for screening biocides,which provide solutions to all the industries using biocides including leather industry,considering the potentially harmful effect of biocides to humans and the environment.
文摘Organic biocides as timber preservatives have aroused more and more attention,because metal salts especially arsenic,chrome and so on, have been suspected to be poisonous to the soil and aquatic animals,as well as the disposal of preserved timber wastes.Therefore,a number of effective organic biocides have been selected to prevent wood or bamboo from decay,mildew, stain and so on.Most of these products have entered into the market.With people’s increasing awareness of the environmental protection,organic biocides will eventually play important roles in timber preservation in the future.This paper summarized the studies on application of organic biocides as wood or bamboo preservatives,including resistant mechanisms,commonly applied types and effects against wood or bamboo fungi,approaches to detecting the amount of organic biocides in timber and their influences on the environment.Based on the discussion above,the authors predicted the developing prospect of organic biocides in timber preservation.
基金the funding support from Foshan University,Chinathe Natural Sciences and Engineering Research Council of Canada(NSERC)
文摘Nanoparticles have been used as diagnostic and therapeutic agents in the human medical field for quite some time, though their application in veterinary medicine and animal production is still relatively new. Recently,production demands on the livestock industry have been centered around the use of antibiotics as growth promoters due to growing concern over microbial antibiotic resistance. With many countries reporting increased incidences of antibiotic-resistant bacteria, laws and regulations are being updated to end in-feed antibiotic use in the animal production industry. This sets the need for suitable alternatives to be established for inclusion in feed.Many reports have shown evidence that nanoparticles may be good candidates for animal growth promotion and antimicrobials. The current status and advancements of nanotechnological applications in animal production will be the focus of this review and the emerging roles of nanoparticles for nutrient delivery, biocidal agents, and tools in veterinary medicine and reproduction will be discussed. Additionally, influences on meat, egg, and milk quality will be reviewed.
文摘The use of seawater for industrial cooling is a vital technology that poses some of the most profound environmental impact on the water quality in the Arabian Gulf. Biocide (chlorine) is added to the seawater to control biofouling of the cooling system. This added chlorine reacts with bromide and other chemicals naturally exist in the water to form a wide range of oxidants. Regrettably, reactions between the residual oxidants and natural organic matter in the water lead to formation of toxic halogenated organic compounds that have detrimental effects on the environment when they are discharged into the Gulf. This paper describes the formation of trihalomethanes (THMs) in seawater cooling systems. Results of kinetic experiments have shown that concentrations of THMs increased rapidly with time during the first half hour. Chlorination of seawater has shown significant increase in total THMs (TTHMs) and in bromoform concentrations. Rapid decrease of UV absorbance at 254 nm was also observed during seawater chlorination which is indicative of natural organic matter degradation into small organic molecules including THMs and other by-products. The increase in chlorine dose was accompanied with an increase in TTHMs and bromoform concentrations. Linear relationships between total chlorine concentration and both final TTHMs and bromoform concentrations were established. First order exponential decay and exponential associate functions were developed to correlate chlorine dose with formed THMs.
文摘The science and technology interact with the art in several ways. Biotechnological coupled with analytical approaches can play an important role in protecting and preserving cultural heritage for future generations. Many microorganisms influenced by environmental conditions are the main responsible for biological contamination in built heritage. Biocides based on chemical compounds have been used to mitigate this problem. Thus, it is vitally important to develop proper remediation actions based on environmentally innocuous alternative. Bacillus specie is emerging as an optimistic alternative for built heritage treatment due to their capacity to produce secondary metabolites with antagonistic activities against many fungal pathogens. Therefore, the intent of this work was to access a rapid evaluation of antifungal potential of bioactive metabolites produced by Bacillus strains and simultaneously their characterization using spectroscopic (NMR) and chromatographic techniques (LC-ESI-MS). The high antifungal activity obtained for Bacillus sp. active compounds produced in this study confirms the great potential to suppress biodeteriogenic fungi growth on historical artworks. Additionally, the proposed methodology allowed to access bioactive metabolites produced without need of the laborious total previous isolation and could be used as a viable alternative to be employed for screening and production of new green biocides.
文摘Seawater desalination is one of the major industrial activities along the coastline of Kuwait that poses profound environmental impact on the quality of seawater.This study focuses on investigating the potential contamination of biocides,volatile organic hydrocarbons(VOCs)and other halogenated hydrocarbons discharged from Az-Zour desalination plant.Chemical contamination by residual chlorine(RC)and some VOCs was detected in effluents from inside and at the vicinity of the plant.RC ranged between 0.15 and 0.49 mg/L while bromoform(CHBr3)was the highest of all the VOCs detected and ranged between 0.22 and 3.30μg/L.Benzinoides(benzene,toluene,xylene and ethylbenzene)were also detected at 0.1μg/L and 0.25μg/L.The levels of RC as measured in the vicinity of the Az-Zour plant are below the limit set up by Kuwait EPA.However,it still poses effects to the nearby aquatic life and therefore,it is important to lower the concentration of RC in the discharge effluent.
文摘Background: Annonaceous acetogenins enclose a large number of biological activities, among which the insecticidal stands out. Methods: We report herein the biocide effects of natural acetogenins from Annona squamosa, A.?muricata and A. montana seeds: annonacin, cis-annonacin, cis-annonacin-10- one, asimicin, rolliniastatin-2, cherimolin-1, cherimolin-2, almuñequin, and two β-OH acetogenins: laherradurin and itrabin on Spodoptera frugiperda Smith (Lepidoptera: Noctuidae). Also, some acetylated and methoxy methylated ACG derivatives were synthesized and evaluated: annonacin (3 OAc), annonacin (4 OAc), asimicin (3 OAc), rolliniastatin-2 (3 OAc), rolliniastatin-2 (MOM), laherradurin (3 OAc) and itrabin (3 OAc). Results: The natural acetogenin rolliniastatin-2 (100 μg·g-1 of diet) produced the most important toxic action causing 100% mortality of early instar larvae. Derivatization of ACG yielded compounds that produced nutritional alterations. The incorporation of rolliniastatin-2 (3 OAc) and rolliniastatin-2 (3 MOM) (100 μg·g-1) into the artificial diet of Spodoptera frugiperdadisplayed the strongest antifeedant effects causing marked decreasings in larval growth and adult lethal malformations. Conclusion: Natural acetogenins are promising metabolites for insect control. Derivatization of these compounds reduces their toxicity to early instar larvae.
文摘Annonaceous acetogenins enclose a large number of biological activities, among which the insecticidal stands out. <em>Spodoptera frugiperda</em> is a pest that affects corn crops among others and has a great capacity to develop resistance to traditional insecticides, which represents sufficient reasons for the search for new alternatives for their control. The objective of this study was to determine the appropriate concentration and screening new natural insecticides against second instar larvae of <em>S. frugiperda</em>, under glasshouse conditions on <em>Zea mays</em> L. Natural products such as annonaceous acetogenins and some acetylated and methoxy methylated ACG derivatives and the commercial product Lambda-cyhalotrin (LC) were evaluated. The percent mortalities of <em>S. frugiperda </em>larvae in glasshouse conditions were recorded after 24, 48 and 72 h of treatment application. The results showed that the acetogenins tested were significantly (P < 0.05) different in relation to pest mortality than untreated check. After 72 h of treatment application the highest percent mortalities were obtained with the mixture of two natural products, rolliniastatin-2 (<strong>5</strong>) (100 μg/mL) + squamocin (<strong>6</strong>) (100 μg/mL) + LC (50 μg/mL) that proved the most effective and gave (100%), while rolliniastatin-2 (<strong>5</strong>) at 100 μg/mL alone, gave lowest percent mortality (65%), followed by squamocin (<strong>6</strong>) at 100 μg/mL (55%) and LC at 50 μg/mL (30%). The acetylated and methoxy methylated ACGs derivatives caused very low mortality (25% - 35%). It is recommended the mixture as a management option of <em>S. frugiperda</em> as a component of integrated pest management. The results allow us to infer that the addition of natural ACGs synergizes the insecticidal activity of the commercial product. Finding a new ecological alternative for insect control.
文摘Emulsive polymerization of mono- and dy(meth)acrylates of butandiol, decid(meth)acrylate, methyl-α-alkilacrylates with industrial acrylic monomers—butylacrylate, methylacrylate, methacrylic acid, methyl(meth)acrylate has been investigated. Structurization of copolymers using dy(meth)acrylates of butandiol, braking of emulsive polymerization using water insoluble biocides, dy(meth)acrylates of butandiol and methyl-α-alkilacrylates have been determined. The mechanism of emulsive polymerization of (meth)acrylic monomers using methyl-α-alkilacrylates has been investigated.
文摘Objective:To evaluate in vitro effects of Tagetes minuta L. essential oil(TEO) on L3 Anisakis larvae type 1. Methods:In order to evaluate the potential use of Tagetes minuta essential oil against L3 Anisakis larvae three different media were tested:1) a saline solution(SS); 2) an industrial marinating solution; 3) sunflower seeds oil(SO). For each media and concentrations of TEO(0.1%,0.5%,1.0% and 5.0% v/v),20 parasites were introduced into plastic Petri dishes(diameter 90 mm) and maintained at room temperature. As controls,larvae were maintained without TEO under identical experimental conditions in SS,MS and SO. A total of 900 larvae were tested. The normalized mean viability,LT100,LT50 and the percentage of inactivation at 24 hours were calculated. Results:In vitro tests revealed a complete inactivation of parasites in saline solution after 2 hours with 5% and 1% of TEO. In marinating solution,a complete inactivation of parasites was observed after 4 hours at all concentrations used. A slower activity for all TEO concentration was reported in SO. Conclusions:The results obtained,showing a strong activity against Anisakis larvae,confirm TEO as a larvicidal agent in the treatment of human anisakidosis and in the industrial marinating process.
文摘Silver Nanoparticles were synthesized by Esche- richia coli using Silver nitrate in the growth me-dium and characterized in X-Ray Diffraction, UV-Vis Spectrophotometer and Scanning Electron Microscope. They exhibited antimicrobial activity against human pathogens except Escherichia Coli. Nanoparticles were impregnated in yarn and ana-lyzed for their inhibition in the broth culture. The Minimal Inhibitory Concentratio was calculated for the human pathogens in Microtitre plate. The toxicity assessment of the nanoparticles in the embry-onic Zebrafish showed many organogensis deformi-ties like cardiac malformations, eye and head edema, tail and trunk flexure were observed in the organ system of the developing embryos for 1 to 5 day post fertilization in different concentrations of Ag Nanoparticles. The Organogenesis disruptive effects were found in 14 - 20 ng/ml of silver nanoparticles but the inhibition was found in 4-10ng/ml for the pathogens in vitro and 10ng/ml in embryos. Nevertheless, in Cardiac assay, the Heart Beat rates were calculated as 42 - 45 for 15 Sec in the concentrations ranging from 10 - 20 ng/ml of Silver nanoparticles. The blood flows, rhythmicity, contractility of heart beat rates were observed normal. The Mean value of blood Cell counting did not showed any notable effects in the Nanoparticle treated Zebrafish embryos and control. The LC50 value for the Biosynthesized nanoparticle was at 22 ng/ml in all the developmental stages of the em-bryos. Our results shows silver nanoparticles dis-rupts the normal organogenesis during development and further detailed studies are needed to prove silver nanopartcles are an antimicrobial agent for use in humans.
文摘Toxic pollutants are metabolic poisons that can seriously injure or destroy the photosynthetic organisms upon which the food chain depends. Since microalgae play a key role in marine ecosystems, marine microalgae are proposed as excellent bio-indicators of pollution due to their high sensitivity, which can give warning of the toxic effects of chemicals sooner than any other species. The aim of this work concentrated on the effect of different concentrations of the antifouling biocide (Irgarol 1051) on growth and chlorophylls content (as an essential metabolite) of the two marine unicellular green algae Chlorella salina and Dunaliella bardawil that usually used in fish feeding. The growth of the wall-less Dunaliella bardawil was more sensitive to Irgarol 1051 than the walled cells Chlorella salina, although the concentrations used were greatly different. The product of photosynthesis in the two algal species greatly affected since in the presence of Irgarol 1051, a serious destructive effect was observed. The cell wall appeared to play a significant role in protecting the organism against toxicity of the antifouling agent either by adsorption or degradation. The strength of toxicity depends mainly on the concentration of the antifouling agent, the length of culturing period and the type of organism tested.
文摘Ferrocyanides of Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) were synthesized and characterized by IR spectra, magnetic susceptibility, thermal gravimetric analysis, elemental analysis and X ray diffraction studies. Antimicrobial potential of these complexes have been evaluated. Antifungal screening of these complexes has been carried out against Mycogone perniciosa and Verticillium fungicola causing wet and dry bubble diseases of button mushroom respectively. Nickel ferrocyanide has been found to be most effective against Mycogone perniciosa with 60% inhibitory effect while cadmium ferrocyanide has exhibited significant potential of 85% against Verticillium fungicola.
文摘In this research we decided to analyze the addition of silver(Ag°)on zinc oxide(ZnO)utilizing two nanoparticles:the synthesized zinc oxide-doped-silver nanoparticles(ZnO/Ag_Lab)utilizing the zinc nitrate as metal precursor for ZnO and silver nitrate as metal precursor for Ag°;and the commercial nanoparticle ZnO/Ag.For the study of application of the nanoparticles,they were processed in the form of films and the polymer utilized was the blend of HMSPP(high melt strength polypropylene)and styrene-ethylene/butadiene-styrene.For the study of nanoparticles,they were submitted to biocide tests against Staphylococcus aureus(ATCC 6538)and Escherichia coli(ATCC8739)and XRD(X-Ray Diffraction).The XRD analysis results indicated,in both of nanoparticles,with the presence of wurtzite phase of ZnO,being that on the commercial nanoparticles the intensity of peak was higher than that of synthesized one,on other hand,the peaks attributed to Ag°,were more intense in the synthesized nanoparticle.
文摘Wood can be a suitable alternative to energy-intensive materials in various applications.Nev-ertheless,its susceptibility to weathering and decay has significantly hindered the broad adop-tion of the most commercially significant wood species.While current solutions do tackle certain challenges,they often come with disadvantages like high costs,environmental risks,and/or in-efficiencies.Nanotechnology-based methods can be employed to mitigate these weaknesses and create durable,sustainable wood materials.In this review,we delve into cutting-edge advance-ments in the development of biodeterioration-resistant wood through innovative nanotechnol-ogy approaches.These methods usually involve the application of nanomaterials,either pos-sessing biocidal properties or serving as carriers for biocides.We systematically describe these approaches and compare them to conventional wood modification methods.Additionally,this re-view provides a brief overview of the prevalent biodeteriorating organisms and their mechanisms of action,which notably impact the development and choice of a suitable strategy for wood mod-ification/treatment.Given the requirements of biodeteriorating organisms for growth and wood degradation,it is expected that the new nanotechnology-based approaches to enhance wood dura-bility may provide innovative broad-spectrum biocidal nanosystems.These systems can simulta-neously induce alterations in the physicochemical properties of wood,thereby constraining the availability of the growth requirements.These alterations can efficiently inhibit the biodeterio-ration process by decreasing water absorption,restricting access to the wood components,and reducing void spaces within the wood structure.Finally,this review highlights the new oppor-tunities,challenges,and perspectives of nanotechnology methods for biodeterioration-resistant wood,through which some techno-economic,environmental and safety aspects associated with these methods are addressed.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.NRF-2021R1F1A1063967)。
文摘The exposure patterns of pest control and disinfection workers have changed after the coronavirus disease 2019(COVID-19)outbreak,but the health risks of chemical exposure have not been assessed.We identified these workers’chemical exposure patterns and risks before and after the COVID-19 outbreak.We used data conducted between 2018(pre-pandemic)and 2021(post-pandemic)from three-year cross-sectional surveys on pest control and disinfection workers.Inhalation and dermal exposure concentrations were estimated using equations based on a biocidal product risk assessment model from the Korean National Institute of Environmental Research.The non-carcinogenic and carcinogenic risks of chemicals were calculated using the United States Environmental Protection Agency risk assessment model.We found that the annual work frequency(50^(th)percentile)of foggers using disinfectants increased the most among all the work types,from 140 uses/year to 176 uses/year after the COVID-19 outbreak.Moreover,all chemicals’non-carcinogenic and carcinogenic risks increased regardless of exposure routes.In the worst scenario(95^(th)percentile),the margin of exposure for citric acid,benzethonium chloride,benzyl-C12-16-alkyldimethyl chlorides,and sodium chlorite of inhalation exposure,and isopropyl alcohol and benzyl-C12-16-alkyldimethyl chlorides of dermal exposure were acceptable(>100)before the COVID-19outbreak but became unacceptable(<100)after the COVID-19 outbreak.Carcinogenic risks of dichlorvos from inhalation and dermal exposure were above acceptable levels(>10^(-6))before and after the COVID-19 outbreak but comparatively high after the COVID-19 outbreak.Additionally,significantly more workers experienced health symptoms after the COVID-19outbreak(p<0.05),with the most common being muscle lethargy(31%),skin/face stinging(28.7%),and breath shortness/neck pain(24.1%).
基金financially supported by the National Natural Science Foundation of China(Nos.21774086 and 21935008)the Natural Science Foundation of Jiangsu Province(No.BK20180093)+1 种基金the Suzhou Municipal Science and Technology Foundation(No.SYS2018026)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Attachment of bacteria and subsequent formation of biofilms on material surfaces lead to serious consequences including infection,contamination and biofouling,posing a prominent threat to human health and causing problems in many industries.Therefore,it is highly desirable to endow the surfaces with antibacterial properties.Traditional antibacterial surfaces are designed via either bacteria-resisting strategy to prevent the initial adhesion of bacteria or bacteria-killing strategy to eradicate any bacteria that attach to the surface.However,these single-function surfaces have their inherent shortcomings and cannot realize long-term efficacy against bacteria.In recent years,various dual-function antibacterial surfaces with both bacteria-resisting and bacteria-killing properties together have been developed,showing better performance for combating surface-attached bacteria and preventing formation of biofilms.In this review,we summarize the recent development of these dual-function antibacterial surfaces.We focus on the design principles and fabrication strategies of such surfaces and highlight the representative examples,which are categorized specifically into two types according to the anti-adhesive and bactericidal properties are simultaneous or switchable.A brief perspective is finally presented on current challenges and future research directions.
基金financially supported by the National Natural Science Foundation of China(No.51501201)。
文摘The corrosion damage of 20 SiMn steel by sulphate-reducing bacteria(SRB)and the mitigation effect of organic silicon quaternary ammonium salt(OSA)were studied in sterilized mild alkaline simulated concrete pore solution(STR)with different additions of SRB and OSA at pH 9.35 for 28 days.Uniform corrosion occurs in STR medium while slight localized corrosion is observed in STR+OSA medium,and localized pitting corrosion occurs in STR+SRB and STR+SRB+OSA media.The largest pit depth reduces from 36.70μm in STR+SRB medium to 3.31μm in STR+SRB+OSA medium due to the mitigation effect of OSA.The corrosion rate reflected by weight loss and electrochemical impedance spectroscopy(EIS)results presents the order of STR<STR+OSA<STR+SRB+OSA<STR+SRB,which also proves that the presence of SRB can accelerate corrosion in a carbonated medium.However,OSA as an efficient bacteriostatic agent can reduce the excessive growth of SRB and thus reduce corrosion.