Prevention Of Contamination Research Articles

Ensiling process and pomegranate peel extract as a natural additive in potential prevention of fungal and mycotoxin contamination in silage

A study was conducted on six animal feed centers in Israel where fungal and mycotoxin presence was examined in maize and wheat silages. Fumonisin mycotoxins FB1 and FB2 were present in every maize silage sample analyzed. Interestingly, no correlation was found between the occurrence of specific mycotoxins and the presence of the fungal species that might produce them in maize and wheat silages. We further investigated the effect of pomegranate peel extract (PPE) on Fusarium infection and fumonisin biosynthesis in laboratory-prepared maize silage. PPE had an inhibitory effect on FB1 and FB2 biosynthesis by Fusarium proliferatum, which resulted in up to 90 % reduction of fumonisin production in silage samples compared to untreated controls. This finding was supported by qRT-PCR analysis, showing downregulation of key genes involved in the fumonisin-biosynthesis pathway under PPE treatment. Our results present promising new options for the use of natural compounds that may help reduce fungal and mycotoxin contamination in agricultural foodstuff, and potentially replace traditionally used synthetic chemicals.

Development of Optical-based and Imaging Technology Detection, Diagnosis and Prevention of Aflatoxin Contamination on Maize Crop

Development of Optical-based and Imaging Technology Detection, Diagnosis and Prevention of Aflatoxin Contamination on Maize Crop

Histological biomarkers and biometric data on trahira Hoplias malabaricus (Pisces, Characiformes, Erythrinidae): a bioindicator species in the Mearim river, Brazilian Amazon.

The objective of this study was to evaluate the levels of environmental contamination in a protected area in the Brazilian Amazon. For this, two areas were chosen along the Mearim River: the reference area (A1) and the potentially contaminated area (A2), where water samples were collected, for physicochemical and microbiological analyses, as well as specimens of Hoplias malabaricus, for the evaluation of biometric data and incidence of branchial lesions. The physicochemical analyzes of the water from both areas showed contamination (low levels of dissolved oxygen, tubidity and high iron concentrations, especially in A2). The microbiological analyzes showed that all water samples showed total coliform values higher than those acceptable by CONAMA and WHO (with higher values in A2), in addition to E. coli values higher than those allowed by legislation in A2. Regarding biometric data, male and female fishes were significantly longer and heavier in A1 during the dry and rain seasons and the gonadosomatic index also showed higher values in A1 than in A2 in both seasons. H. malabaricus showed gill lesions of minimal to moderate pathological importance in A1 and A2, indicating that specimens from both areas of the Mearim River showed biological responses to contamination. The observed changes in the water quality, bimetic parameters and the histological analyzes of the specimens of H. malabaricus directly reflect on the quality and health of the fishes in the Mearim River, and point to the urgent need for prevention and remediation of contamination in these ecosystems.

Plasmonic enhancement of the antibacterial photodynamic efficiency of a zinc tetraphenylporphyrin photosensitizer/dextran graft polyacrylamide anionic copolymer/Au nanoparticles hybrid nanosystem.

A zinc tetraphenylporphyrin photosensitizer/dextran graft polyacrylamide anionic copolymer/Au nanoparticles (ZnTPP/D-g-PAAan/AuNPs) triple hybrid nanosystem was synthesized in water-based solution as a nanodrug for potential photodynamic therapy applications. Dynamic light scattering studies showed that the nanosystem is stable against aggregation and sedimentation for several days after preparation. The dependence of the ZnTPP fluorescence intensity on the gold concentration in the ZnTPP/D-g-PAAan/AuNPs nanosystem has been revealed to be non-monotonic, with a maximum 2.5-fold enhancement at a concentration of 0.008 g L−1. The non-monotonic dependence was explained to be caused by two competing processes, namely plasmonic enhancement and FRET, indicating the existence of an optimal concentration of Au NPs that can provide the highest plasmonic enhancement of the electronic processes involving the ZnTPP photosensitizer. A 2.6-fold enhancement of singlet oxygen photogeneration under excitation resonant with the localized surface plasmon resonance of the Au NPs has been detected for ZnTPP/D-g-PAAan/AuNPs, proving the plasmonic origin of this phenomenon. The high bactericidal efficiency of ZnTPP/D-g-PAAan/AuNPs water-based solution under 420 nm and 530 nm light irradiation was revealed against wild strains of Staphylococcus aureus. Therefore, the ZnTPP/D-g-PAAan/AuNPs nanosystem can potentially be used in photodynamic therapy for the prevention and treatment of the bacterial contamination of open wounds.

Evaluation of Self-Efficacy-Based Intervention: Improving School Food Handlers’ Selected Food Safety Behavior

Food safety training of food handlers is commonly used to reduce the incidence of foodborne disease worldwide. Nevertheless, studies have shown that the provision of knowledge alone may not necessarily result in a positive behavior change. Thus, this study aimed to determine the effect of a multiple-component intervention approach, comprising training and a self-efficacy building program, to improve hand washing and contamination prevention behavior among food handlers at public school canteens in Malaysia. Two groups were compared: treatment (n = 31) and control (n = 30). The treatment group received a 2-h on-site interactive training and a self-efficacy building program that incorporated verbal persuasion, role modeling, and practice time. Both groups were measured using a survey and the direct observation method, before and after a 14-day intervention period. Results show that the intervention package produced a significant increase (P < 0.001) in the behavioral compliance, knowledge, and self-efficacy scores for both behaviors. An increase in the overall frequency of soap use and adherence to the correct hand washing technique for the treatment group was recorded, although there is room for improvement in the post intervention hand washing compliance score. Findings from this study provide valuable information on possible ways to improve food safety behavior among school food handlers.

A One Health perspective on water contaminants

One Health is a transdisciplinary approach considering human, animal, and environmental health, and is highly relevant to water management. The growing pressure of anthropogenic activities is leading to water contamination with biological, chemical, and physical contaminants. For example, pathogens may result from fecal contamination due to poor sanitation or livestock waste leachate, agrochemicals from intensive agricultural practices, sediments from soil erosion, or microplastics from a wide range of anthropogenic activities. These activities can have widespread impacts, as exemplified by nitrates leaching from agricultural fields to surface and drinking waters, which can impact human health (e.g., methemoglobinemia), animal health (e.g., abortions and hypoxia), and environmental health (e.g., eutrophication). Recommendations include an integrated One Health approach to water contamination prevention: (i) respect for sociocultural practices; (ii) improved land management; (iii) improved infrastructures for water and wastewater management; (iv) surveillance of water bodies; (v) improved agricultural practices; and (vi) prevention through environmental management systems.

Effect of Knowledge and Attitudes towards Prevention and Control of COVID-19 Infection

The aim of this paper is to investigate the effect of knowledge (general knowledge on COVID-19 and transmission knowledge on COVID-19) and attitudes towards prevention and control of COVID-19 contamination. In this study, an online survey approach was used, and primary data were collected through structured questionnaire from 410 respondents’ who actively participated in the survey. This study is conducted based on Theory of Planned Behavior (TPB). Five (5) research hypotheses were constructed in order to fulfill the objective of this study. The proposed research hypotheses were tested by using PLS-SEM techniques. The results showed that entirely all five hypotheses were accepted. Precisely, general knowledge on COVID-19, transmission knowledge on COVID-19 and attitudes towards prevention & control positively contributes to the behavior towards prevention and control of COVID-19 infection. Furthermore, the findings suggest that proper knowledge and optimistic attitudes on COVID-19 may change the behavioral pattern of people to prevent and control the COVID-19 infection. The outcomes of this study are significant to convey future efforts to focus onsocial preparation to conform the pandemic control measures. One of the significant drawbacks of this study is that the data was collected through online questionnaire survey and during pandemic

The maltose transporter subunit IICB of the phosphotransferase system: An important factor for biofilm formation of Cronobacter

Cronobacter is a common food-borne opportunistic pathogen, which is easily to form biofilm and difficult to remove. The regulation mechanism on the biofilm formation of Cronobacter has drawn more and more attention. In here, transcriptomic sequencing of free and biofilm states of Cronobacter was performed, and analyzed to identify the differential gene expression through Gene Ontology (GO) function, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment. Based on sequencing analysis of the results, the malX gene encoding maltose transporter subunit IICB in the phosphotransferase system (PTS) might be involved in the formation of Cronobacter biofilm and thus selected for gene knockout. Hereafter, the changes in biofilm formation ability, extracellular polymer and biofilm-related gene expression of malX gene knockout strains were detected to explore the potential mechanism of malX gene on biofilm formation of Cronobacter. From the result, weaken biofilm formation ability of Cronobacter, decreased extracellular polysaccharide content and down-regulated expression of cellulose-related genes were obtained after knockout of malX gene, which verified our deduction. This study is the first to elucidates the regulation mechanism of the PTS on the biofilm formation of Cronobacter, which lays a foundation for the further prevention and control of food contamination caused by Cronobacter.

Important interventions in the operating room to prevent bacterial contamination and surgical site infections

The aim of this study was to explore interventions that Swedish operating room (OR) nurses considered important for the prevention of bacterial contamination and surgical site infections (SSIs). A web-based cross-sectional survey with an open-ended question was answered by OR nurses and analyzed using summative content analysis and descriptive statistics. The OR nurses (n=890) worked within 11 surgical specialties and most of them worked at university hospitals (37%) or county hospitals (53%). The nurses described twelve important interventions to prevent bacterial contamination and SSI: skin disinfection (25.9%), the OR environment (18.2%), aseptic technique (16.4%), OR clothes (13.4%), draping (9.8%), preparation (6.1%), dressing (3.6%), basic hygiene (3.4%), normothermia (2.1%), communication (0.7%), knowledge (0.3%), and work strategies (0.2%). Skin disinfection was considered the most important intervention in order to prevent bacterial contamination and SSI. The responses indicated that many OR nurses believed the patients' skin to be sterile after the skin disinfection process. This is not a certainty, but skin disinfection does significantly decrease the amount of bacterial growth. This study shows that many OR nurses' interventions are in line with recommendations. Although, knowledge regarding the effect of skin disinfection needs further research, and continued education.

Predicting factors of public awareness and perception about the quality, safety of drinking water, and pollution incidents.

Public perception of drinking water quality and safety results from the interaction of multiple factors, including the public engagement, which requires sufficient knowledge and awareness. This issue has yet to be addressed in Algeria. This study investigated the residents' perception and awareness about the drinking water quality, safety, and water pollution events. A survey-based cross-sectional study was conducted amongst citizens living in the province of Biskra. Multinomial regression analysis was used to identify the predicted public perception factors about drinking water-related issues. Regardless of the degree of public trust in the drinking water sources, the main drinking water source reported by the participants was tank water (43.3%) followed by tap water (32%). Water quality standards are a measure of the condition of water relative to the contaminants. Water consumption profiles gave priority attention to taste (48.7%), odour (35%), appearance (34.7%), and colour (32%), reflecting a low level of knowledge about the water quality standards. Most of the residents (55.7%) reported a deficient communication about the preventive measures to protect public health. The higher level of education showed a statistically significant impact in discriminating between those who felt very satisfied and dissatisfied participants with the drinking water quality and those who felt between satisfied and dissatisfied (P = 0.023, P = 0.034, respectively). Additionally, education level had a statistically significant role in differentiating trust levels in drinking water quality between two groups, those belonging to either confident or relatively confident and the group of extremely worried respondents, with P = 0.000 and P = 0.000, respectively. Interviewed respondents with certain education levels showed higher trust in the safety of drinking water when compared to those with lower education levels. Gender had a significant role in differentiating the group of respondents who were relatively confident from those who were extremely worried (P = 0.016). The public knowledge about the standards of water quality, safety, and the pollution-related issues remains relatively low. This study is of interest to policy makers and public health authorities who implement actions for water contamination prevention and public health protection. These findings could have national implications and are also applicable, in general context, particularly in low and middle-income countries.

Comparative study of machine learning models for evaluating groundwater vulnerability to nitrate contamination

The accurate evaluation of groundwater contamination vulnerability is essential for the management and prevention of groundwater contamination in the watershed. In this study, advanced multiple machine learning (ML) models of Radial Basis Neural Networks (RBNN), Support Vector Regression (SVR), and ensemble Random Forest Regression (RFR) were applied to determine the most accurate performance for the evaluation of groundwater contamination vulnerability. Eight vulnerability factors of DRASTIC-L were rated based on the modified DRASTIC model (MDM) and were used as input data. The adjusted vulnerability index (AVI) with nitrate values was used as output data for the modeling process. The performance of three models was verified using the statistical performance criteria of MAE, RMSE, r2, and ROC/AUC values. The ensemble RFR model showed the highest performance in comparison with standalone SVR and RBNN models. Specifically, ensemble RFR kept all promising solutions during the model performance due to its flexibility and robustness, and the vulnerability map obtained by the RFR model was more accurate for predicting the most vulnerable areas to contamination. It was concluded that ensemble RFR was a robust tool to enhance the evaluation of groundwater contamination vulnerability, and that it could contribute to environmental safety against groundwater contamination.

Multidimensional Food Security Nexus in Drylands under the Slow Onset Effects of Climate Change

Hyperarid, arid, semiarid, and dry subhumid areas cover approximately 41% of the global land area. The human population in drylands, currently estimated at 2.7 billion, faces limited access to sufficient, affordable, and nutritious food. We discuss the interlinkages among water security, environmental security, energy security, economic security, health security, and food security governance, and how they affect food security in drylands. Reliable and adequate water supply, and the prevention of water contamination, increase the potential for ample food, fodder, and fiber production. Protecting woodlands and rangelands increases food security by buffering the slow onset effects of climate change, including biodiversity loss, desertification, salinization, and land degradation. The protection of natural lands is expected to decrease environmental contamination, and simultaneously, reduce the transfer of diseases from wildlife to humans. Biofuel production and hydroelectric power plants increase energy security but generate land-use conflicts, deforestation, and ecosystem degradation. Economic security generally positively correlates with food security. However, economic growth often degrades the environment, changes tenure rights over natural resources, and stimulates migration to urban areas, resulting in lower food and health security. Moreover, civil unrest, political instability, and armed conflicts disrupt local economies in drylands. Maintaining food security is crucial for health security; conversely, malnourished populations and unresponsive health systems decrease economic security, and adversely affect environmental, energy, and food security. Climate change is expected to deteriorate health security by spreading vector-borne diseases. Effective governance and timely interventions can substantially shorten periods of food insecurity, lower their intensities, and accelerate recovery from inevitable crises, and are therefore crucial in preventing humanitarian crises. Since global drylands population will nearly double by 2050, and since drylands are among the most susceptible areas to climate change, integrated multi-hazard approaches to food security are needed.

Environmental contamination with parasites in selected rural farms in the Philippines: impacts of farming practices on leafy greens food safety.

Fresh vegetables are an important part of a healthy diet, however, they can also be agents of transmission of intestinal parasites. This study aimed to evaluate the presence of parasite contamination in vegetable farms as a source of transmission in selected rural communities in Laguna, Philippines. A total of 168 vegetable, 55 soil and 15 water samples collected from four selected farms and a reference farm were processed through various standard parasitological techniques. Of these, 17.3% of vegetables, 47.3% soil and 73.3% water samples were found contaminated with parasites’ eggs or cysts. Interestingly, leafy vegetables, such as lettuce, were found to be more contaminated. Results showed that strongylids/hookworms (egg/larva) showed the highest prevalence in farm soil (38.2%) and vegetable (13.1%); other helminth parasite eggs were also recovered such as Toxocara sp., Ascaris sp., Trichiuris, Trichostrongylus sp. and protozoan cysts of Balantidium coli. Cryptosporidium sp. oocysts of and Giardia sp. cysts were observed in all water samples in the farms. Furthermore, results revealed that some farming practices such as the use of improperly treated animals manure as fertilizers, unhygienic practice of farmers and sanitation issues were factors that contribute to parasite contamination in the farms. These findings have implications on food safety in poor-resource communities posing public health risks. Recommendations were discussed in the study for the control and prevention of parasite contamination at the farm level.

Environmental crisis effect on environmental costs

Environmental management accounting is a mechanism for determining and evaluating, and incorporating these cost and benefit in the day-to-day business decision making, the full spectrum of environmental costs of current production processes and the economic benefits of contamination prevention, or cleaner processes. In practice, the past 10 years have acquired significance from corporate accounting, which is the most prominent part of cost accounting. Limits were widely acknowledged of conventional financial and cost accounting techniques reflecting companies’ sustainability efforts and providing management with necessary information for sustainable business choices. Information on companies’ environmental performance may be somewhat accessible, but both domestic decision makers and those at the level of public authorities are seldom able to connect environmental information with economic variables and are essentially deprived of environmental cost information. Decision makers do thus not recognize the economic worth of natural resources as asset and the commercial and financial benefit of excellent environmental performance. Beyond ‘goodwill’ efforts, there are a number of market-based incentives for integration with decision making of environmental issues. This article provides an outline of environmental management methods and we evaluate environmental costs in terms of current economic crisis.

Perchlorate occurrence, sub-basin contribution and risk hotspots for drinking water sources in China based on industrial agglomeration method

Perchlorate is a persistent inorganic contaminant which has attracted wide attention because of its harmful effects on physical health. Despite the potential adverse effects to humans via drinking water, related research at the national scale in China are scarce. In this study, the occurrence of perchlorate in major river basins in China was investigated from 2009 to 2020. Generally, except for the Yangtze River Basin, perchlorate concentrations in the surface water of other river basins were low, ranging from < 0.01 to 8.53 μg/L. The results of a specialized field sampling and tracking program in the Yangtze River Basin in 2019 showed that the Xiangjiang River basin is the greatest contributor of perchlorate in the Yangtze River Basin, accounting for 58.63% of the total perchlorate input. Furthermore, based on correlation analysis between production enterprise information and measured concentrations in sampled sites, fireworks and explosives production industries were identified as the major sources of perchlorate contamination in surface water. The risk map showed that the central-southern part of China and the central part of Xinjiang province were risk hotspots for perchlorate contamination. The results gave insights into how to conduct more precise risk assessment and policy intervention towards prevention of perchlorate contamination.

AflN Is Involved in the Biosynthesis of Aflatoxin and Conidiation in Aspergillus flavus.

Aspergillus flavus poses a threat to society economy and public health due to aflatoxin production. aflN is a gene located in the aflatoxin gene cluster, but the function of AflN is undefined in Aspergillus flavus. In this study, aflN is knocked out and overexpressed to study the function of AflN. The results indicated that the loss of AflN leads to the defect of aflatoxin biosynthesis. AflN is also found to play a role in conidiation but not hyphal growth and sclerotia development. Moreover, AlfN is related to the response to environmental oxidative stress and intracellular levels of reactive oxygen species. At last, AflN is involved in the pathogenicity of Aspergillus flavus to host. These results suggested that AflN played important roles in aflatoxin biosynthesis, conidiation and reactive oxygen species generation in Aspergillus flavus, which will be helpful for the understanding of aflN function, and will be beneficial to the prevention and control of Aspergillus flavus and aflatoxins contamination.

A novel chlorhexidine-hexametaphosphate coating for titanium with antibiofilm efficacy and stem cell cytocompatibility

Dental implants are an increasingly popular way to replace missing teeth. Whilst implant survival rates are high, a small number fail soon after placement, with various factors, including bacterial contamination, capable of disrupting osseointegration. This work describes the development of chlorhexidine-hexametaphosphate coatings for titanium that hydrolyse to release the antiseptic agent chlorhexidine. The aim was to develop a coating for titanium that released sufficient chlorhexidine to prevent biofilm formation, whilst simultaneously maintaining cytocompatibility with cells involved in osseointegration. The coatings were characterised with respect to physical properties, after which antibiofilm efficacy was investigated using a multispecies biofilm model, and cytocompatibility determined using human mesenchymal stem cells. The coatings exhibited similar physicochemical properties to some implant surfaces in clinical use, and significantly reduced formation of multispecies biofilm biomass up to 72 h. One coating had superior cytocompatibility, with mesenchymal stem cells able to perform normal functions and commence osteoblastic differentiation, although at a slower rate than those grown on uncoated titanium. With further refinement, these coatings may have application in the prevention of bacterial contamination of dental implants at the time of surgery. This could aid a reduction in rates of early implant failure.

A Procedure to Investigate the Efficacy of the Blood Donor Arm Disinfection Procedure for the Prevention of Blood Contamination

The safety of blood products has improved drastically over the years especially when it comes to the detection of viral pathogens. Contamination by bacteria and fungi remains a concern since these lead to transfusion transmitted infections. This project aims to provide a protocol to determine the efficacy of the disinfection procedure used by Blood Establishments. This method is based on collecting swab samples from the antecubital fossa of donors before and after the application of the disinfectant and by culturing of blood collected from the diversion pouch. The colony counts obtained before and after disinfection from the selected Blood Bank were analysed statistically and it was found that the disinfectant regimen currently used was more than sufficient in obtaining the required bacterial reduction and that it eliminated any fungal organisms. From the blood cultures performed, three blood cultures resulted as positive. Upon further investigation using a MALDI-TOF MS based identification technique, the contaminant bacteria were identified. None of these organisms were deemed to have originated because of improper disinfection upon reviewing the identification results obtained from the after-disinfection swabs. This implies that the current disinfection procedure is performing as expected.

Heat shock in Cronobacter sakazakii induces direct protection and cross-protection against simulated gastric fluid stress

The bacterial heat shock response in foodborne pathogens is caused by exposure to higher temperatures which poses a great threat to food safety because it can undermine food processing interventions and host defense. The study assessed the heat and acid resistance of Cronobacter sakazakii following heat shock (53 °C for 15min). Inactivation curves of the heat-shocked and non-shocked C. sakazakii cells at four temperatures (56, 58, 60, and 62 °C) and simulated gastric fluid (SGF, pH 3.0) were examined and fitted with the log-linear model and the Weibull model. The inactivation parameters obtained on the basis of the Weibull model showed that heat shock significantly (p < 0.05) increased the values of δ (time to reach 1 log reduction) and t3d (time to reach 3 log reduction) under thermal and acid inactivation. The results proved that heat shock provided C. sakazakii direct protection from a more adverse heat challenge and cross-protection from SGF, i.e. there was a heat shock response. Results of sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) revealed that seven protein species showed enhanced expression, while four protein species showed decreased expression in the heat-shocked compared to the non-heat-shocked C. sakazakii cells. Quantitative real-time reverse transcriptase PCR (RT-qPCR) revealed upregulation of six stress related genes, ibpA, ibpB (both encoding molecular chaperons), Hsp15 (encoding heat shock protein), Hsp20 (encoding small heat-shock protein), HspQ (encoding proteases) and rpoS (encoding stationary phase sigma factor), following heat shock treatment. In addition, heat shock induced an increase proportion of saturated fatty acids (SFA), cyclic fatty acids (CFA) and the ratio of saturated fatty acids to unsaturated fatty acids (SFA/USFA), whereas reducing the proportion of unsaturated fatty acids (USFA). Consequently, establishment of inactivation models of C. sakazakii could provide data support for quantitative microbial risk assessment (QMRA). Exploration of enhanced resistance mechanisms might provide clues for prevention and control of contamination by heat-shocked C. sakazakii.

Estimation of Bacterial Contamination on Toothbrush used by Different Students for a Different Time Period

Introduction: Contamination of a surface occurs by microorganisms when it inhabits any surface or an object when the count of the bacteria increases. The degree of contamination can be estimated by counting the number of colonies, when a sample collected from that site is cultured. Streptococcus mutans is considered to be the normal commensal of our oral cavity. When it’s count is increased in the oral cavity, it causes dental caries and other tooth related problems. The main aim of this study is to estimate the bacterial contamination in the tooth brush head used by students for varying time periods.&#x0D; Materials and Methods: Used toothbrushes for varying time periods are collected from students. Then their bristles are plucked with the sterilized forceps for the prevention of bacterial contamination and agitated in the saline and inoculated in the brain heart infusion broth agar with the help of sterilized bacterial loops and incubated for 24 hours at 37oC. Then the colonies are counted and record as CFU/ml.&#x0D; Results: The bacterial count is directly proportional to period of usage, but it is affected by certain factors like duration of brushing and using brushes. On an average the count was estimated to be 47 CFU/ml for two months, 57 CFU/ml for six months, 68 CFU/ml for eight months and 81 CFU/ml for a year. The p1 value (for sample 1 and 2) was 0.046 (p&lt;0.05), so it is statistically significant.&#x0D; Conclusion: The study shows that in prolonged usage of tooth brushes the bacterial contamination also increases. So the tooth brushes should be protected in tooth brush holders, to avoid contamination and the toothbrushes should be changed once in a month for betterment of oral health.