Effects of cherries Sanitization methods and fermentation times on quality parameters of coffee beans.

For the first time, the dual effect of coffee cherry sanitization methods to control the microbial load in processing and the influence of fermentation time on coffee quality parameters was evaluated. Two assays were carried out by wet processing: I) Sanitization of the coffee cherry (ST1: Unclassified processed cherries; ST2: Classified and sanitized cherries with drinking water; ST3: Classified and sanitized cherries with a chemical agents and II) Fermentation times (FT1: 12 h; FT2: 24 h; FT3: 48 h; FT4: 72 h and FT5: 96 h). pH, temperature, and dissolved oxygen were monitored during fermentation. Counts of Lactic Acid Bacteria - LAB, mesophiles, and yeasts were carried out on the coffee mass before and after fermentation. Caffeine and chlorogenic acid contents were determined by HPLC-DAD and the sensory profile by methodology for specialty coffees (SCA). The main findings showed that: sanitization with Timsen® did not significantly influence the evolution of pH during fermentation (p > 0.05), but it can reduce to a small extent the action of LAB at the end of the process. It was observed that the temperature of the coffee mass tends to balance with the ambient temperature, with significant effects (p < 0.05) of sanitization (ST2 and ST3) on the stability of this variable during fermentation. Timsen® as a disinfectant affected microbial populations and improved the sensory profile in the cup. In prolonged coffee fermentations (FT3, FT4 and FT5), the pH of the coffee mass tended to stabilize after 36 h, regardless of the process time. Likewise, a correlation was evident between a higher microbial load correlated with better sensory profiles in FT4 and FT5. Neither the sanitization process nor the fermentation time significantly affected the caffeine and chlorogenic acid contents of the coffee, both in its green and roasted states. Consequently, the sanitization of cherry coffee with Timsen® and prolonged fermentation times favor the safety and coffee final quality in the cup.

Higienização de ambiente em agroindústria familiar de embutidos cárneos / Environmental hygienization in family meat product

A higienização é um procedimento importante na indústria de alimentos e sua realização deve ocorrer rotineiramente para evitar que os alimentos sejam contaminados. Além disso, todos os manipuladores de alimentos devem receber treinamentos de modo a entender como ocorrem as contaminações e como evitá-las, para que não ocorra deterioração antecipada dos alimentos e para que não exponham os consumidores ao risco de doenças transmitidas por alimentos em caso de contaminação. Esta pesquisa avaliou o processo de higienização e sua eficiência em superfícies presentes em uma agroindústria da agricultura familiar produtora de embutidos cárneos. Apesar de ter instalações adequadas a agroindústria apresentava inadequações quanto aos produtos utilizados e a frequência inadequada para uma higienização eficiente. Foi realizada análise microbiológica das superfícies dos equipamentos para contagem de aeróbios mesófilos e notou-se uma elevada carga microbiana que indicou uma baixa eficiência no processo de higienização. Sugeriu-se melhorias na higiene ambiental associado à instrução dos colaboradores, para contribuir na promoção da qualidade dos produtos, aumento dos lucros e salvaguardando a saúde do consumidor.

Hygiene is an important procedure in the food industry, and its performance must occur routinely to prevent food from being contaminated. In addition, all food handlers must receive training in order to understand how contamination occurs and how to avoid it, so that there is no anticipated deterioration of food and that consumers are not exposed to the risk of foodborne diseases. in case of contamination by pathogenic microorganisms. Thus, this research evaluated the cleaning process and its efficiency on surfaces present in a family farming agroindustry that produces meat products, which despite having adequate facilities, had some difficulties such as product use and inadequate frequency for eficiente cleaning. After performing a microbiological analysis to count surface mesophilic aerobes, a high level of contamination was noted, relating to low efficiency in the cleaning process. Improvements in environmental hygiene are suggested, associated with the instruction of employees for the implementation of the Standard Operating Hygiene Procedure, promoting improvements in product quality, increasing profits and safeguarding consumer health.

Sanitization of hydroponic farming facilities in Singapore: what, why, and how.

This study performed microbial analysis of nutrient film technique (NFT) hydroponic systems on three indoor farms in Singapore (the "what"). To justify the necessity of sanitizing hydroponic systems, strong biofilm-forming bacteria were isolated from the facility and investigated for their influence on Salmonella colonization on polyvinyl chloride (PVC) coupons in hydroponic nutrient solutions (the "why"). Finally, sanitization solutions were evaluated with both laboratory-scale and field-scale tests (the "how"). As a result, the microbiome composition in NFT systems was found to be highly farm specific. The strong biofilm formers Corynebacterium tuberculostearicum C2 and Pseudoxanthomonas mexicana C3 were found to facilitate the attachment and colonization of Salmonella on PVC coupons. When forming dual-species biofilms, the presence of C2 and C3 also significantly promoted the growth of Salmonella (P < 0.05). Compared with hydrogen peroxide (H2O2) and sodium percarbonate (SPC), sodium hypochlorite (NaOCl) exhibited superior efficacy in biofilm removal. At 50 ppm, NaOCl reduced the Salmonella Typhimurium, C2, and C3 counts to <1 log CFU/cm2 within 12 h, whereas neither 3% H2O2 nor 1% SPC achieved this effect. In operational hydroponic systems, the concentration of NaOCl needed to achieve biofilm elimination increased to 500 ppm, likely due to the presence of organic matter accumulated during crop cultivation and the greater persistence of naturally formed multispecies biofilms. Sanitization using 500 ppm NaOCl for 12 h did not impede subsequent plant growth, but chlorination byproduct chlorate was detected at high levels in the hydroponic solution and in plants in the sanitized systems without rinsing. IMPORTANCE: This study's significance lies first in its elucidation of the necessity of sanitizing hydroponic farming systems. The microbiome in hydroponic systems, although mostly nonpathogenic, might serve as a hotbed for pathogen colonization and thus pose a risk for food safety. We thus explored sanitization solutions with both laboratory-scale and field-scale tests. Of the three tested sanitizers, NaOCl was the most effective and economical option, whereas one must note the vital importance of rinsing the hydroponic systems after sanitization with NaOCl.

Daily Use Water Bottles as a Hub for Microbial Population: A Comparative Study of PET vs. Stainless Steel Water Bottles and Outcome of Washing Strategy Intervention.

Water bottles for everyday usage are a typical addition to people's life and offer a practical way to stay hydrated. Even though safe and clean water is preferred for consumption, the water bottle or container used to drink water was never considered to be cleaned. Here, we examined the adhering microbial populations in water bottles composed of stainless steel (SS) and polyethylene terephthalate (PET). A total of 30 water bottles-15 PET and 15 SS-were gathered from different users. To identify and quantify the adhering microbial populations, microbial swabs from the inside surface of the bottles were collected and later cultivated on certain growth media. Overall the microbial load of PET is significantly higher than the SS water bottles of 68.8 + 19.1 cfu/ml and 35.4 + 8 cfu/ml respectively at initial sampling (P = 0.0027). We also evaluated the efficiency of various cleaning procedures in eliminating adherent bacteria populations. The cleaning strategy significantly reduced the microbial load (P<0.0001). The mean load observed was 11.2 + 2.3 cfu/ml post-wash. This comparison study offers important new information about the adherent microbial populations found in SS and PET water bottles used every day, in the end. This finding emphasizes the necessity of routine cleaning and upkeep of these bottles to reduce the possibility of microbial contamination and the accompanying health risks.

Impact of intense sanitization procedures on bacterial communities recovered from floor drains in pork processing plants.

Background: Pork processing plants in the United States (US) cease operations for 24-48 h every six or twelve months to perform intense sanitization (IS) using fogging, foaming, and further antimicrobial treatments to disrupt natural biofilms that may harbor pathogens and spoilage organisms. The impact such treatments have on short-term changes in environmental microorganisms is not well understood, nor is the rate at which bacterial communities return. Methods: Swab samples were collected from floor drains to provide representative environmental microorganisms at two US pork processing plants before, during, and after an IS procedure. Samples were collected from four coolers where finished carcasses were chilled and from four locations near cutting tables. Each sample was characterized by total mesophile count (TMC), total psychrophile count (TPC), and other indicator bacteria; their biofilm-forming ability, tolerance of the formed biofilm to a quaternary ammonium compound (300 ppm, QAC), and ability to protect co-inoculated Salmonella enterica. In addition, bacterial community composition was determined using shotgun metagenomic sequencing. Results: IS procedures disrupted bacteria present but to different extents depending on the plant and the area of the plant. IS reduced TPC and TMC, by up to 1.5 Log10 CFU only to return to pre-IS levels within 2-3 days. The impact of IS on microorganisms in coolers was varied, with reductions of 2-4 Log10, and required 2 to 4 weeks to return to pre-IS levels. The results near fabrication lines were mixed, with little to no significant changes at one plant, while at the other, two processing lines showed 4 to 6 Log10 reductions. Resistance to QAC and the protection of Salmonella by the biofilms varied between plants and between areas of the plants as well. Community profiling of bacteria at the genus level showed that IS reduced species diversity and the disruption led to new community compositions that in some cases did not return to the pre-IS state even after 15 to 16 weeks. Discussion: The results found here reveal the impact of using IS to disrupt the presence of pathogen or spoilage microorganisms in US pork processing facilities may not have the intended effect.

Eco-Friendly Sanitization of Indoor Environments: Effectiveness of Thyme Essential Oil in Controlling Bioaerosol Levels and Disinfecting Surfaces.

Bioaerosols and pathogens in indoor workplaces and residential environments are the primary culprits of several infections. Techniques for sanitizing air and surfaces typically involve the use of UV rays or chemical sanitizers, which may release chemical residues harmful to human health. Essential oils, natural substances derived from plants, which exhibit broad antimicrobial properties, could be a viable alternative for air and surface sanitation. The objective of this study has been to investigate the efficacy of thyme essential oil (TEO) in environmental sanitation processes. In Vitro assays through agar well diffusion, disk volatilization and tube dilution methods revealed significant antimicrobial activity of TEO 100% against foodborne and environmental isolates, with both bacteriostatic/fungistatic and bactericidal/fungicidal effects. Therefore, aqueous solutions of TEO 2.5% and 5% were formulated for air sanitation through nebulization and surface disinfection via direct contact. Bioaerosol samples and surface swabs were analyzed before and after sanitation, demonstrating the efficacy of aqueous solutions of TEO in reducing mesophilic and psychrophilic bacteria and environmental fungi levels in both air and on surfaces. The obtained results prove the antimicrobial potential of aqueous solutions of TEO in improving indoor air quality and surface cleanliness, suggesting thyme essential oil as an effective and safe natural sanitizer with minimal environmental impact compared to dangerous chemical disinfectants.

Antibacterial activity of Cymbopogon species essential oils against Xanthomonas citri and their use in post-harvest treatment for citrus canker management.

Citrus canker is a disease caused by the gram-negative bacterium Xanthomonas citri subp. citri (X. citri), which affects all commercially important varieties of citrus and can lead to significant losses. Fruit sanitization with products such as chlorine-based ones can reduce the spread of the disease. While effective, their use raises concerns about safety of the workers. This work proposes essential oils (EOs) as viable alternatives for fruit sanitization. EOs from Cymbopogon species were evaluated as to their antibacterial activity, their effect on the bacterial membrane, and their ability to sanitize citrus fruit. The in vitro assays revealed that the EOs from C. schoenanthus and C. citratus had a lower bactericidal concentration at 312 mg L-1, followed by 625 mg L-1 for C. martini and C. winterianus. Microscopy assay revealed that the bacterial cell membranes were disrupted after 15 min of contact with all EOs tested. Regarding the sanitizing potential, the EOs with higher proportions of geraniol were more effective in sanitizing acid limes. Fruit treated with C. shoenanthus and C. martini showed a reduction of ∼68% in the recovery of viable bacterial cells. Therefore, these EOs can be used as viable natural alternatives in citrus fruit disinfection.

Reviewing the evidence of antimicrobial activity of glycols.

In the 1940s and 1950s, researchers seeking safe and novel ways to eliminate airborne pathogens from enclosed spaces, investigated glycol vapours as a method of disinfection. More recently, the COVID-19 pandemic highlighted the need for a non-toxic aerial disinfectant that can be used in the presence of people. This scoping review is intended to analyse the early and more recent literature on glycol disinfection, scrutinizing the methodologies used, and to determine if the use of glycols as modern-day disinfectants is justified PRISMA-ScR guidelines were used to assess the 749 articles retrieved from the Web of Science platform, with 46 articles retained after the search strategy was applied. Early studies generally demonstrated good disinfection capabilities against airborne bacteria and viruses, particularly with propylene glycol (PG) vapour. Vapour pressure, relative humidity, and glycol concentration were found to be important factors affecting the efficacy of glycol vapours. Contact times depended mainly on the glycol application method (i.e. aerosolization or liquid formulation), although information on how glycol efficacy is impacted by contact time is limited. Triethylene glycol (TEG) is deemed to have low toxicity, carcinogenicity, and mutagenicity and is registered for use in air sanitization and deodorization by the US Environmental Protection Agency. Glycols are also used in liquid formulations for their antimicrobial activity against a wide range of microorganisms, although when used as a non-active excipient in products, their contribution to antimicrobial efficacy is rarely assessed. The appropriate use of liquid glycol-containing formulations was found to positively impact the antimicrobial capabilities of disinfectants when used at temperatures <0, food preservatives, and dental medicaments. Providing modern delivery technology can accurately control environmental conditions, the use of aerosolized glycol formulations should lead to successful disinfection, aiding infection prevention, and control regimens.

Impact of intense sanitization on environmental biofilm communities and the survival of Salmonella enterica at a beef processing plant.

Salmonella enterica is a leading cause of foodborne illness in the U.S. In the meat industry, one action taken to address pathogen contamination incidence is an intense sanitization (IS) of the entire processing plant that many large processors perform annually or semiannually. However, this procedure's immediate and long-term impact on environment microbial community and pathogen colonization are unknown. Here we investigated the impact of IS procedure on environmental biofilms and the subsequent S. enterica colonization and stress tolerance. Environmental samples were collected from floor drains at various areas 1 week before, 1 week, and 4 weeks after the IS procedure at a beef plant with sporadic S. enterica prevalence. Biofilm formation by microorganisms in the drain samples without S. enterica presence was tested under processing temperature. The ability of the biofilms to recruit and/or protect a co-inoculated S. enterica strain from quaternary ammonium compound (QAC) treatment was determined. The community structure of each drain sample was elucidated through 16S rRNA amplicon community sequencing. Post-IS samples collected from 8 drains formed significantly stronger biofilms than the respective pre-IS samples. S. enterica colonization was not different between the pre- and post-IS biofilms at all drain locations. S. enterica survival in QAC-treated pre- and post-IS mixed biofilms varied depending upon the drain location but a higher survival was associated with a stronger biofilm matrix. The 16S rRNA amplicon gene community sequencing results exhibited a decrease in community diversity 1 week after IS treatment but followed by a significant increase 4 weeks after the treatment. The IS procedure also significantly altered the community composition and the higher presence of certain species in the post-IS community may be associated with the stronger mixed biofilm formation and Salmonella tolerance. Our study suggested that the IS procedure might disrupt the existing environmental microbial community and alter the natural population composition, which might lead to unintended consequences as a result of a lack of competition within the multispecies mixture. The survival and recruitment of species with high colonizing capability to the post-IS community may play crucial roles in shaping the ensuing ecological dynamics.

Sporadic regional re-emergent cholera: a 19th century problem in the 21st century.

Cholera, caused by Vibrio cholerae, is a severe diarrheal disease that necessitates prompt diagnosis and effective treatment. This review comprehensively examines various diagnostic methods, from traditional microscopy and culture to advanced nucleic acid testing like polymerase spiral reaction and rapid diagnostic tests, highlighting their advantages and limitations. Additionally, we explore evolving treatment strategies, with a focus on the challenges posed by antibiotic resistance due to the activation of the SOS response pathway in V. cholerae. We discuss promising alternative treatments, including low-pressure plasma sterilization, bacteriophages, and selenium nanoparticles. The paper emphasizes the importance of multidisciplinary approaches combining novel diagnostics and treatments in managing and preventing cholera, a persistent global health challenge. The current re-emergent 7th pandemic of cholera commenced in 1961 and shows no signs of abeyance. This is probably due to the changing genetic profile of V. cholerae concerning bacterial pathogenic toxins. Given this factor, we argue that the disease is effectively re-emergent, particularly in Eastern Mediterranean countries such as Lebanon, Syria, etc. This review considers the history of the current pandemic, the genetics of the causal agent, and current treatment regimes. In conclusion, cholera remains a significant global health challenge that requires prompt diagnosis and effective treatment. Understanding the history, genetics, and current treatments is crucial in effectively addressing this persistent and re-emergent disease.

Perspectives and Attitudes of Newer New Jersey High School Teachers towards Cleaning, Sanitizing, and Disinfecting Consumer Products Used in School Classrooms.

During the COVID-19 pandemic, there was an increased reported use of chemical cleaning, sanitizing, and disinfecting products (CSDPs), which created public concerns about negative health consequences for both children and adults in public schools. A subset of newer teachers shared experiences regarding safety and health (S&H) while working in school-based settings through a series of online surveys. Surveys were provided to teachers who completed work-based learning supervisory trainings provided by the New Jersey Safe Schools Program between October 2021 and June 2023. The participants answered questions focusing on CSDPs purchased for school use, their attitudes towards CSDPs, their use of personal protective equipment, and symptoms employees may have had due to CSDPs. A total of 205 teacher participants successfully completed the surveys. Over 25% of the teachers did not know where their CSDPs originated from, as they were provided by the school. Most participants "sometimes", "not often", or "never" read labels for CSDP ingredients or looked them up on healthy product apps. The participants (60%) tended to wear gloves while cleaning/disinfecting but did not wear masks. A third of the participants experienced respiratory health problems after working at school. Overall, the data suggest that more education on S&H regarding CSDPs needs to be provided to New Jersey teachers.

Enhanced antimicrobial efficacy of biogenic ZnO nanoparticles through UV-B activation: A novel approach for textile garment.

Zinc oxide nanoparticles (ZnO NP) are characterized by novel properties which have been attracting the attention of different lines of research due to their wide applicability. Obtaining this nanomaterial is strongly linked to biogenic synthesis methods, which have also been developed in this research, using Coriandrum sativum extract as a reducing agent. ZnO NPs have been properly characterized by techniques to evaluate their morphology by transmission electron microscopy (TEM) and elemental analysis by EDX. The evaluation of the antimicrobial and antifungal effects is linked to the use of a system provided by "locker sanitizer" equipment, which has been designed and built as part of this research, and is intended to treat textile garments by nebulizing the ZnO NP colloid (99.08 µg/mL) + UV-B, water + UV-B, and UV-B only, and also to evaluate the influence of the treatment time for 1, 2 and 3 min. In this sense, it is known that the nanomaterial used shows a better response to UV light because more hydroxyl radicals are produced, leading to a higher reaction rate, which results in greater efficiency in inhibitory processes. The results show that the use of the locker sanitizer is more efficient when using ZnO NP + UV-B light since it achieved 100 % growth inhibition against E. coli, C. albicans, and A. brasiliensis, and >99 % against S. aureus, after 3 min of treatment.

Impact of the COVID-19 pandemic on behavioral changes in healthcare workers in Italy.

Introduction: During the COVID-19 pandemic, adherence to wearing face mask and washing hands procedures and achieving high COVID-19 vaccine coverage among healthcare workers (HCWs) were essential to minimize morbidity and possible death and limit the transmission of the virus. The objectives of the cross-sectional survey were to explore the influence of COVID-19 on the use of preventive measures and vaccination willingness among HCWs in the southern part of Italy and the associated factors. Methods: The survey was carried out from 15 June 2023 to 15 July 2023 among 521 HCWs who worked in three randomly selected public hospitals. All data were collected through a self-administered questionnaire. Results: HCWs had a positive change in the use of preventive measures if they did not often/always use them before the pandemic, but they are using in the current epidemiologic context and they were willing to use in a future epidemic situation. A positive change in the adherence to face mask-wearing (24.6%) was more likely among those with at least 5 years of university degree, nurses/midwives, and who had worked in COVID-19 wards. A positive change in alcohol-based hand rubbing (3.1%) was more likely in HCWs in Emergency/Critical/Infectious Diseases wards compared with medical wards. HCWs who were more likely to believe that the COVID-19 vaccine should be mandatory for them (58.1%) had at least 5 years of university degree, in Emergency/Critical/Infectious Diseases wards compared with surgical and medical wards, had received more than three doses of this vaccine, were more concerned to get infected during their activity, and had received information from scientific journals. HCWs more willing to receive the COVID-19 vaccine every year (39.8%) were males, physicians, those in Emergency/Critical/Infectious Diseases wards compared with medical wards, who had received more than three doses of this vaccine, who believed that this vaccine should be mandatory for HCWs, and who needed additional information. Discussion: The survey showed that the COVID-19 pandemic had an impact on the use of preventive measures among HCWs, not necessarily for the improvement or increase. Educational messages on the importance of these measures regarding the promotion and recommendation of the vaccine need to be investigated and applied among HCWs in order to reduce vaccination gaps and the spread of the infection.

Designing 3D-Printed Mesh-Covered Fluid Collecting Racks (MFCRs) to Prevent Moisture-Related COVID-19 Sampling Interruptions in Taiwan.

Background: A sampling platform (or table) set at the patient's side in a zero-exposure screening center (booth) might be used for specimen collection during public health crises such as the COVID-19 pandemic. However, repeated sanitization causes moisture problems. Such moisture problems would not only be noted by patients but also interrupt the sampling process. In this study, we aimed to develop 3D-printed mesh-covered fluid collecting racks (MFCRs) to address surface moisture problems to determine whether MFCRs can shorten the sampling time. Methods: This was an observational, descriptive, and cross-sectional study. We observed the reasons for sampling interruptions related to surface moisture problems among patients who used MFCRs or did not (April 28-30, 2022). We used a 3D printer to make an MFCR, which measured 14.5 cm in width and length and 1.0 cm in height. The MFCR allows the ethanol to drain through the mesh into the fluid collection rack below to leave a relatively dry surface on the mesh. Finally, we calculated the median time to finish sampling between MFCRs and non-MFCRs. Results: A total of 400 patients were randomly observed (using MFCRs, n = 200; non-MFCRs, n = 200). Patients in the non-MFCR group were more likely to interrupt the sampling process (n = 39, 19.5%) by noting surface moisture problems than those in the MFCR group (n = 3, 1.5%). Two of the major interruptions, "asking questions about the moist surface" (from 12% to 1%) and "slowing down their actions" (from 4.5% to 0.5%), were obviously improved by using MFCRs. Overall, the median sampling time was significantly shorter (p < 0.001) in the group using MFCRs (0.6 min) than in the group using non-MFCRs (1.5 min). The MFCRs shortened the sampling time by 60%, which might be associated with decreasing interruptions caused by surface moisture problems. Conclusions: The 3D printed MFCRs are suitable for handling surface moisture problems caused by repeated sanitizations. More importantly, the MFCRs might be associated with decreasing interruptions caused by moisture problems.

Metabolomics investigation of global responses of Cronobacter sakazakii against common sanitizing in infant formula processing environments.

Cronobacter sakazakii, an opportunistic bacterium, has raised a serious outbreak in powdered infant formula recent years. In this work, four sanitizing strategies used during infant formula processing, including chlorine, quaternary ammonium chloride (QAC), 60 °C heating, and malic acid (MA), were utilized against C. sakazakii among planktonic, air-dried (A), and air-dried & washed (AW) state, followed by an exploration of the metabolic responses induced by these treatments via a dual-platform metabolomics analysis with the ultra-high performance liquid chromatography-mass spectrometry and nuclear magnetic resonance. In the planktonic state, MA was the most effective in inhibiting bacterial growth, followed by chlorine, QAC, and 60 °C heating. Under A state, the efficacy of heating improved considerably, compared to that in the planktonic state, and remained unaltered under AW state. Chlorine and QAC were ineffective to control bacterial growth under A state, but their efficacy rose under AW state. Furthermore, the metabolomic analysis revealed chlorine induces amino acids catabolism, membrane lysis, and depression in carbohydrate and nucleotide metabolism in both planktonic and AW states, while the initiation of antioxidation mechanism was only found under AW state. Although the metabolic change caused by QAC in the planktonic state was similar to chlorine, the accumulation of osmoprotectant and membrane phospholipids within the AW cells reflected the effort to restore intracellular homeostasis upon QAC. Heating was characterized by considerable amino acid anabolism, along with mildly perturbed carbohydrate and nucleotide metabolism for heat shock protein preparation in both states. Lastly, MA promoted amino acid-dependent acid resistance under the planktonic state, and the regulation of antioxidation and osmoprotection under AW state. The metabolomics study elucidated the intracellular perturbation induced by common sanitizing, as well as the bacterial response, which provides insights for novel sanitization development.

In vitro activity of sanitizers against mono- and polymicrobial biofilms of C. parapsilosis and S. aureus.

The emergence of disinfectant-resistant microorganisms poses a significant threat to public health. These resilient pathogens can survive and thrive in hospital settings despite routine disinfection practices, leading to persistent infections and the potential for outbreaks. In this study, we investigated the impact of 11 different commercial sanitizers at various concentrations and exposure times on biofilms consisting of clinical and nosocomial environmental isolates of Candida parapsilosis and Staphylococcus aureus. Among the sanitizers tested, 0.5% and 2.0% chlorhexidine (CLX), 10% polyvinyl pyrrolidone (PVP-I), a disinfectant based on quaternary ammonium compound (QAC), 2% glutaraldehyde, and 0.55% orthophthalaldehyde (OPA) demonstrated efficacy against both C. parapsilosis and S. aureus in monospecies and mixed biofilms. Analysis showed that 0.5% CLX and 10% PVP-I had fungicidal and bactericidal activity against all biofilms. However, the sanitizer based on QAC and 0.55% OPA proved to be bacteriostatic and fungicidal against both monospecies and mixed biofilms. In mixed biofilms, despite the last four sanitizers exerting fungicidal action, the reduction of fungal cells was approximately 4 log10 CFU/mL compared to monospecies biofilms, showing that the interaction provided more resistance of the yeast to the sanitizer. Formation of mixed biofilms in hospital settings can create an ecological niche that enhances the survival of pathogens against routine sanitization procedures. Therefore, effective sanitization practices, including regular cleaning with effective sanitizers, should be implemented to prevent C. parapsilosis/S. aureus biofilm formation in healthcare settings.

Electrolyzed Hypochlorous Acid (HOCl) Aqueous Solution as Low-Impact and Eco-Friendly Agent for Floor Cleaning and Sanitation.

Recently, the use of disinfectants has been becoming a diffused and sometimes indiscriminate practice of paramount importance to limit the spreading of infections. The control of microbial contamination has now been concentrated on the use of traditional agents (i.e., hypochlorite, ozone). However, their prolonged use can cause potential treats, for both human health and environment. Currently, low-impact but effective biocides that are prepared in a way that avoids waste, with a very low toxicity, and safe and easy to handle and store are strongly needed. In this study, produced electrochemically activated hypochlorous (HOCl) acid solutions are investigated and proposed, integrated in a scrubbing machine for floor cleaning treatment. Such an innovative machine has been used for floor cleaning and sanitation in order to evaluate the microbial charge and organic dirt removal capacity of HOCl in comparison with a machine charged with traditional Ecolabel standard detergent. The potential damage on floor materials has also been investigated by means of Scanning Electron Microscope (SEM). A comparative Life Cycle Assessment (LCA) analysis has been carried out for evaluating the sustainability of the use of the HOCl-based and detergent-based machine.

Efficacy of cold plasma-activated water as an environmentally friendly sanitizer in egg washing.

Eggs in the United States are typically washed using chemical sanitizers such as quaternary ammonia (QA) or chlorine. Such treatments generate wash water, which could be potentially hazardous to the environment. A novel, nonthermal sanitization technique for washing shell eggs using cold plasma-activated water (PAW) was investigated in this study. The inactivation efficacy of PAW on Klebsiella michiganensis and the impact of PAW on the cuticle of the eggshell and shell strength were tested in comparison to QA. Washing inoculated eggs with PAW and QA achieved a similar microbial reduction (>5.28 log CFU/egg). Colorimetric analysis showed that ∆E-value for PAW-treated eggs was significantly lower than QA-treated eggs, suggesting higher cuticle coverage in eggs treated with PAW. The texture analysis to test for shell egg strength indicated that washing eggs with PAW did not affect the structural integrity of the eggshell when compared to eggs washed with QA. According to this study, PAW has the potential as an alternative to commercial sanitizers like QA in the egg-washing industry. PAW does not detrimentally impact shell strength or cuticle coverage and provides similar microbial reduction efficacy.

Efficacy of UV and UV-LEDs Irradiation Models for Microbial Inactivation Applicable to Automated Sterile Drug Compounding.

LEDs development has attracted attention over conventional mercury lamps for the tiny size, high efficiency, long lifetime, low operating temperature. The antimicrobial effectiveness of traditional UV-lamps radiation (wavelength of 254 nm) compared to UV-C LEDs (LED1 wavelength range 275-286 nm and LED2 range 260-270 nm) was carried out, for possible applications to automated sterile drug compounding. The UV lamp and the tested UV-LED devices remarkably reduced microbial load, following a time-dose response, but the best performance was evidenced by LED1, which guaranteed the complete inactivation of high concentrations of bacteria, yeasts, and spores at doses between 200 and 2000 J/m2.

A multi-robot deep Q-learning framework for priority-based sanitization of railway stations.

Sanitizing railway stations is a relevant issue, primarily due to the recent evolution of the Covid-19 pandemic. In this work, we propose a multi-robot approach to sanitize railway stations based on a distributed Deep Q-Learning technique. The proposed framework relies on anonymous data from existing WiFi networks to dynamically estimate crowded areas within the station and to develop a heatmap of prioritized areas to be sanitized. Such heatmap is then provided to a team of cleaning robots - each endowed with a robot-specific convolutional neural network - that learn how to effectively cooperate and sanitize the station's areas according to the associated priorities. The proposed approach is evaluated in a realistic simulation scenario provided by the Italian largest railways station: Roma Termini. In this setting, we consider different case studies to assess how the approach scales with the number of robots and how the trained system performs with a real dataset retrieved from a one-day data recording of the station's WiFi network.