ultraviolet-C Irradiation Research Articles

The effect of ultraviolet-C on the senescence of bitter gourd fruit and the key factors analyzed by transcriptomic and metabolomic analyses

Bitter gourd (Momordica charantia L.) is a tropical and subtropical vegetable that is popular for its rich nutritional content. However, its immature fruit has a short shelf life and spoils easily. This study assessed the effects of ultraviolet-C (UV-C) irradiation on the storage and quality of postharvest bitter gourd fruit. Exposure for 40 s maintained fruit firmness, delayed senescence, increased the antioxidant capacity and minimized damage by reactive oxygen species. Transcriptomic and metabolomic analyses identified 12,733 differentially expressed genes and 282 metabolites during storage. The downregulation of genes for ethylene synthesis and cell wall degradation delayed ripening and senescence, while the upregulation of phenylpropanoid biosynthetic genes enhanced its antioxidant properties. Key transcription factors, such as MYB, bHLH, and bZIP, were implicated in the delayed senescence treatment. This research elucidates the mechanisms of prevention of bitter gourd with UV-C and offers insights into the genetic and metabolite candidates for enhanced strategies of postharvest preservation.

Colorimetric sensors of ultraviolet-C light using diacetylene-zinc(II)-zinc oxide nanocomposites with tunable sensitivity

Polydiacetylene (PDA) material-based colorimetric sensors have been devised for monitoring ultraviolet-C (UVC) light. However, it is rather difficult to systematically control their sensitivity. This work introduces an easy and inexpensive approach for developing diacetylene/zinc(II)/zinc oxide (DA/Zn2+/ZnO) nanocomposites as colorimetric sensors of UVC light. Here, we demonstrate the ability to tune the sensitivity of the nanocomposites to UVC light by varying different parameters including ZnO ratio, ZnO size, and alkyl chain length of DA monomers. We have found that the increase of ZnO ratio significantly enhances the UVC sensitivity. Furthermore, the color transition from blue to purple upon prolonged exposure to UVC light can be controlled by adjusting the ZnO ratio. Interestingly, the use of ZnO quantum dots with a diameter of 3.8 nm drastically increases the sensitivity to UVC light. The adjustment in DA alkyl chain length also enables fine-tuning of sensitivity. The shortening of the alkyl chain length at the tail and headgroup position strongly influences the color-transition behaviors of the nanocomposites upon increasing the UVC irradiation time. Two different types of UVC sensors can be fabricated including flexible film and hydrogel bead sensors. These sensors exhibit a color transition from yellow to green to red as UVC exposure increases from 0 to 16.4 J/cm2.

Bactericidal effect of far ultraviolet-C irradiation at 222 nm against bacterial peritonitis.

Far ultraviolet-C irradiation at 222 nm has potent bactericidal effects against severe infections such as peritonitis, with minimal cytotoxicity. Bacterial peritonitis due to bowel perforation is a serious condition with high mortality despite current treatments. This study investigated the safety and efficacy of intraperitoneal far ultraviolet-C irradiation at 222 nm. In vitro experiments optimized the fluid conditions for bacterial or protein concentrations prior to in vivo evaluation. In vivo efficacy was assessed in a rat peritonitis model induced by Escherichia coli, measuring intra-abdominal bacterial concentration, blood cytokine levels, and mortality rates. Safety was evaluated by analyzing cyclobutane pyrimidine dimers as markers of DNA damage in five abdominal organs: stomach, small intestine, colon, liver, and spleen. Statistical analyses employed parametric methods for normally distributed data and non-parametric methods for data without normality. Optimal in vitro conditions included 106 CFU/mL bacteria, 0.5 mW/cm2 irradiation, and 10-3 mg/mL protein. In the rat model, far ultraviolet-C irradiation at 222 nm significantly decreased intra-abdominal bacteria, reduced blood cytokines (interleukin-1β and interleukin-6), and elevated survival rates from 20% to 60%, compared to lavage alone. The formation of cyclobutane pyrimidine dimers was significantly lower with 222 nm irradiation than with 254 nm, suggesting reduced DNA damage. These findings indicate that far ultraviolet-C irradiation at 222 nm, when combined with lavage, represents a promising therapeutic strategy for bacterial peritonitis, providing effective bacterial reduction and a favorable safety profile. Further research is needed to verify these findings and investigate long-term safety and potential clinical applications.

Effect of UV-C Treatment on the Quality of Fresh-Cut Potatoes Obtained from Tubers of Different Ages

The physico-chemical properties of potato tubers change with age, which can affect not only the quality of the tubers but also the quality and shelf-life of fresh-cut potatoes (FCP) produced from older tubers. One of the methods that has proven useful for extending the shelf-life of some foods is ultraviolet-C (UV-C) irradiation. This study investigated whether UV-C irradiation can mitigate the negative effects of tuber age. FCP from tubers after storage (1 and 9 months), vacuum-packaged, were irradiated with UV-C (2.70 kJ m−2) and stored (6 °C/15 days). The total aerobic mesophilic bacteria count (TAMBC), total and soluble solids content, pH, firmness, color, chlorogenic acid, reducing sugars, sensory properties of raw FCP and subsequently boiled and fried FCP, and acrylamide content in fried FCP were monitored. UV-C irradiation of FCP does not affect all parameters equally for both tuber ages, but was generally effective in reducing TAMBC, and UV-C-treated samples reached a shelf-life of 15 days. UV-C irradiation improved the sensory properties of raw and thermally processed FCP at both ages. UV-C irradiation caused an increase in acrylamide content in fried FCP, regardless of. the tubers age, but all samples were safe in this respect.

Application of UV-C Technology in Managing the Monkeypox Epidemic: Surface, Air, and PPE Decontamination

The outbreak of monkeypox, a zoonotic viral disease, necessitates effective strategies for infection control and decontamination. Ultraviolet-C (UV-C) radiation, with its germicidal properties, has long been utilized for sterilization in various settings. This paper explores the potential of UV-C technology in managing the monkeypox epidemic, focusing on its applications for surface, air, and Personal Protective Equipment (PPE) decontamination. Traditional UV-C methods have demonstrated effectiveness in reducing viral loads on surfaces and in the air, potentially mitigating the spread of monkeypox. Additionally, UV-C can aid in the sterilization of PPE, crucial for protecting healthcare workers and managing supply shortages. The paper also addresses environmental considerations, including the energy consumption and water footprint associated with UV-C systems. The transition to energy-efficient UV-C LEDs and sustainable practices is highlighted as a means to balance efficacy with environmental impact. By integrating UV-C technology with other infection control measures, healthcare facilities and high-risk environments can enhance their response to the monkeypox epidemic while minimizing ecological concerns.

Dry biofilms on polystyrene surfaces: the role of oxidative treatments for their mitigation

Candida auris and Staphylococcus aureus are associated with a wide range of infections, as they exhibit multidrug resistance – a growing health concern. In this study, gaseous ozone, and ultraviolet-C (UVC) radiation are applied as infection control measures to inactivate dry biofilms of these organisms on polystyrene surfaces. The dosages utilised herein are 1000 and 3000 ppm.min for ozone and 2864 and 11592 mJ.cm−2 for UVC. Both organisms showed an increased sensitivity to UVC relative to ozone exposure in a bespoke decontamination chamber. While complete inactivation of both organisms (>7.5 CFU log) was realized after 60 mins of UVC application, this could not be achieved with ozonation for the same duration. However, a combined application of ozone and UVC yielded complete inactivation in only 20 mins. For both treatment methods, it was observed that dry biofilms of S. aureus were more difficult to inactivate than dry biofilms of C. auris. Compared to dry biofilms of C. auris, micrographs of wet C. auris biofilms revealed the presence of an abundance of extracellular material after treatments. Interestingly, wet biofilms were more difficult to inactivate than dry biofilms. These insights are crucial to preventing recalcitrant and recurrent infections via contact with contaminated polymeric surfaces.

Influence of ultraviolet-C irradiation treatment on quality and shelf life of mung bean sprouts during storage

This research analyzed the impact of exposing mung bean sprouts to ultraviolet-C (UV-C) radiation for different periods (2, 5, and 10 min). Treated sprouts were preserved at 5°C and 85-95% relative humidity for 6 days. Irradiation for 10 min effectively reduced fresh weight loss, electrolyte leakage, and microbial count and maintained the firmness of sprouts. It also positively influenced the bioactive components, including antioxidants, total phenols, and protein, potentially providing health benefits to consumers. In addition, prolonged UV-C exposure for 10 min leads to oxidative stress, marked by a rise in malondialdehyde, proline, and hydrogen peroxide content. These compounds assist in stress reduction and preserve secondary metabolites. This research implies that postharvest 10 min UV-C irradiation offers a potential approach to uphold quality while maximizing the nutritional value of mung bean sprouts.

The effect of UV-C radiation and cytokinin on pea plants

Aim. The effect of ultraviolet C (UV-C) radiation and cytokinin benzylaminopurine (BAP) on the growth and content of photosynthetic pigments in leaves of pea plants (Pisum sativum L.) was studied. Methods. Pea plants cultivar Aronis were irradiated by UV-C at a dose of 15 kJ/m2 with a power of 7 W/m2. Part of the non-irradiated plants was treated with BAP, part of the plants was treated with BAP one day before irradiation and part of plants were treated with BAP in one day after UV-C irradiation. Length and mass of plant shoots and roots were measured during the experiment. Content of photosynthetic pigments in leaves were determined during all time the experiment. Results. It was shown that pea plants growth delayed content of carotenoids in leaves reduced after the UV-C radiation of pea plants. Treatment of plants with BAP after the end of the UV-C radiation accelerated the restoration of photosynthetic pigments content. Conclusions. It was shown that UV-C radiation of pea plants by dose of 15 kJ/m2 caused inhibition of growth, decreasing photosynthetic pigments content in leaves. The BAP treatment after radiation stimulated the restoration of photosynthetic pigments content in the leaves.

Global Health Alert: Racing to Control Antimicrobial-Resistant Candida auris and Healthcare Waste Disinfection Using UVC LED Technology

Emerging antimicrobial-resistant (AMR) Candida auris presents a formidable global health challenge, causing severe healthcare-associated infections (HAIs) with high mortality rates. Its ability to colonize surfaces and resist standard disinfectants undermines traditional hygiene practices, prompting an urgent need for new strategies. Ultraviolet C (UVC) light offers a promising approach with rapid and broad-spectrum germicidal efficacy. This review examines current literature on UVC LED technology in combating C. auris, highlighting its effectiveness, limitations, and applications in healthcare hygiene. UVC light has potent activity against C. auris, with up to 99.9999% inactivation depending on certain conditions such as microbial load, type of organism, surface, environmental, equipment, and UVC radiation factors. UVC LEDs can effectively combat C. auris, driving down healthcare costs and reducing attributable global mortality. Here, we explore implementation strategies for the targeted disinfection of high-risk areas and equipment, air handling units (AHUs), and water treatment systems. Challenges associated with UVC LED disinfection devices in healthcare settings, current performance limitations, and radiation safety are discussed. This will help in optimizing application protocols for effective disinfection and radiation safety. To further strengthen healthcare facility hygiene practices and curb the global spread of C. auris, recommendations for integrating UVC LED disinfection into infection control programs are shared.

Evaluating the Impact of UVC Exposure on Forage Maize Seeds under Hydroponic Condition

Background: UV radiation, with shorter wavelengths than visible light, plays a pivotal role in stimulating growth processes and boosting the synthesis of beneficial compounds in plants. Moreover, it triggers morphological changes and genetic responses, shaping plants’ physical traits and adaptability. Nevertheless, a nuanced understanding is necessary as excessive UV exposure can also cause harm, underscoring the complexity of the relationship between UV radiation and plants. The study aimed to evaluate the effect of ultraviolet C (UVC) light exposure on the germination and growth of forage maize seeds under controlled conditions in an indoor crop. One sample of seeds was exposed to UVC light, while the other was not. Methods: The experiment was carried out for 14 days, with the plants subjected to mixed blue-red light, fertigation and kept at a maximum external temperature of 30°C and maximum internal temperature of 25.1°C. UVC light is applied for 10 minutes to the seeds before germination. Result: The results showed that the plants exposed to UVC light had an average growth increase of 3cm compared to those that did not receive the treatment. However, the protein content of both sets of seedlings was similar. The study suggests that further research is necessary to determine the optimal duration and distance for UVC exposure to minimize any potential negative effects on the plants. It also highlights the need to investigate the effect of UVC radiation on the nutritional content of hydroponic crops to ensure that the increased growth does not come at the expense of nutritional quality. The experiment was carried out in Medellin, Colombia, with a maximum solar radiation of 1000 W/m2 and an altitude of 1500 meters. Overall, the study provides evidence that UVC radiation can enhance the growth of hydroponic maize seedlings, but more research is needed to fully understand its effects. At the end, there is an improvement in the growth of forage corn in seeds that have been subjected to UVC light compared to those that have not. It is worth highlighting the need for more research on changes in nutritional components in general.

Surface Cleaning with a Microfiber Cloth and Water followed by Ultraviolet-C Light Exposure Achieves Non-Inferior Disinfection of a Pathogenic Staphylococcus aureus Strain versus Use of Germicidal Wipes.

We hypothesized that ultraviolet-C (UV-C) irradiation (Surfacide, Waukesha, WI) following use of microfiber cloths (Sanny Shop LLC, Longmont, CO) soaked in waterwould be noninferior to surface disinfection wipes containing a quaternary ammonium compound and alcohol (PDI Healthcare, Woodcliff Lake, NJ)for the pathogenic Staphylococcus aureus (S. aureus) sequence type 5 (ST5). This was a randomized laboratory study of disinfection approaches for S. aureusST5. A total of 270 polycarbonate slides loaded with ST5 were prepared for the standard surface disinfection group (N=18) and water-soaked microfiber cloths and UV-C treatment group (N=144), along with positive and negative microbiological controls. All 18 samples of S. aureus ST5 bacteria treated with standard chemical wipes showed complete disinfection (colony forming units (CFU) = 0). All 144 treatments with water-soaked microfiber wipes followed by UV-C exposure showed complete disinfection (CFU =0) regardless of soiling, height from the floor, or orientation to the emitters. The upper 95% exact one-sided confidence limit for any CFU >0 was 2.1%. These data affirm our hypothesis that surface wiping with a damp cloth followed by triangular UV-C irradiation delivery is noninferior to surface disinfection for S. aureusST5 using germicidal wipes, even when UV-C is compromised by height from the floor and orientation to the emitters and surface disinfection is targeted. Removing bioburden with chemical-free microfiber cloths followed by triangular UV-C delivery is a noninferior strategy to targeted surface disinfection with chemical disinfecting wipes for the pathogenicS. aureusST5 strain in the laboratory setting.

Thermoluminescence and ATR-FTIR study of UVC-irradiated low-density polyethylene (LDPE) food packaging

This research aims to study the effects of ultraviolet C (UVC) radiation on low-density polyethylene (LDPE) food packaging. Main objectives include evaluating LDPE degradation and detecting UVC radiation using thermoluminescent dosimeters (TLDs) placed under LDPE samples. Results confirm accurate UVC detection after one hour of exposure, providing a useful tool for optimize food treatment procedures.ATR-FTIR spectroscopy analysis revealed subtle alterations (<8 % transmittance relative) in UVC-irradiated LDPE samples, including possible CH breakage (2910 and 2848 cm−1) and potential CC bond vibrations (1470 cm−1), among others. However, observed variations may stem from LDPE properties rather than entirely from UVC radiation. A comparative study of UVC-induced thermoluminescence (TL) emissions provided insights into various TLDs materials. TL kinetic analysis, using computerised glow curve deconvolution (CGCD) method, unveiled trap charge activation due to UVC exposure, including partial ionization, bleaching effect and photo-transfer (PTTL) processes. LDPE samples amplified UVC-TL responses, revealing intensity differences between the TLDs attributed to the PTTL process, accentuated by the lack of an annealing treatment. Additionally, chemical composition of the TL detectors such as, type, concentration, number, oxidation states and ionic radii of their dopants may influence UVC-TL response. Consequently, TL intensity ratios follow as: GR-200 (LiF: Mg, Cu, P) > TLD-100 (LiF: Ti, Mg) > TLD-400 (CaF2: Mn) > TLD-200 (CaF2: Dy). Thus, GR-200 detects ionizing radiation but cannot distinguish between ionizing and non-ionizing UVC radiation, while TLD-100 has limited effectiveness as a UVC radiation detector. In contrast, TLD-400 is suitable for detecting UVC radiation and TLD-200 emerges as the most favorable UVC detector, showing consistent response levels and minimal PTTL effect placed under the LDPE samples without the need of a thermal annealing treatment that makes the TLD-200 to be reusable in a low-cost measurement protocol.

Impact of Ultraviolet-C Exposure and Mechanical Stress on Conidium Production in Corynespora cassiicola Isolates From Cotton and Soybean

The procurement of inoculum for bioassays with target spot, a significant disease in cotton and soybeans, caused by Corynespora cassiicola can be hindered by the low production of conidia on artificial culture media. The study aimed to determine whether mechanical stress on the mycelium and exposure to ultraviolet-C (UV-C) radiation for varying durations could enhance conidial production in C. cassiicola isolates. Eight isolates from cotton and soy were used, grown in V8 juice medium. After five days of incubation in a climate-controlled chamber, each isolate either underwent mycelium scraping or remained unscraped and was subsequently exposed to UV-C radiation for either 1.0, 1.5 or 2.0 min, in comparison to a control group with zero UV exposure time. Following these procedures, conidial suspensions from each isolate were obtained and quantified (conidia per mL) using a Neubauer chamber The ISO 3S and ISO 4S isolates were found to produce more conidia than the other isolates, regardless of whether they were subjected to mycelium scraping or exposure to UV-C radiation. For most isolates, exposure to UV-C radiation for 1.0-1.5 min led to increased conidium production. Generally, it was not feasible to discern differences in conidial production with respect to the mycelium scraping process. Nevertheless, exposure to UV-C radiation for 1.0 min can be used to induce conidium production in C. cassiicola isolates.

Full-length GSDME mediates pyroptosis independent from cleavage.

Gasdermin (GSDM) family proteins, known as the executors of pyroptosis, undergo protease-mediated cleavage before inducing pyroptosis. We here discovered a form of pyroptosis mediated by full-length (FL) GSDME without proteolytic cleavage. Intense ultraviolet-C irradiation-triggered DNA damage activates nuclear PARP1, leading to extensive formation of poly(ADP-ribose) (PAR) polymers. These PAR polymers are released to the cytoplasm, where they activate PARP5 to facilitate GSDME PARylation, resulting in a conformational change in GSDME that relieves autoinhibition. Moreover, ultraviolet-C irradiation promotes cytochrome c-catalysed cardiolipin peroxidation to elevate lipid reactive oxygen species, which is then sensed by PARylated GSDME, leading to oxidative oligomerization and plasma membrane targeting of FL-GSDME for perforation, eventually inducing pyroptosis. Reagents that concurrently stimulate PARylation and oxidation of FL-GSDME, synergistically promoting pyroptotic cell death. Overall, the present findings elucidate an unreported mechanism underlying the cleavage-independent function of GSDME in executing cell death, further enriching the paradigms and understanding of FL-GSDME-mediated pyroptosis.

Optimized Ultraviolet-C Processing Inactivates Pathogenic and Spoilage-Associated Bacteria while Preserving Bioactive Proteins, Vitamins, and Lipids in Human Milk.

Holder pasteurization (HoP) enhances donor human milk microbiological safety but damages many bioactive milk proteins. Though ultraviolet-C irradiation (UV-C) can enhance safety while better preserving some milk proteins, it has not been optimized for dose or effect on a larger array of bioactive proteins. We determined the minimal UV-C parameters that provide >5-log reductions of relevant bacteria in human milk and how these treatments affect an array of bioactive proteins, vitamin E, and lipid oxidation. Treatment at 6000 and 12 000 J/L of UV-C resulted in >5-log reductions of all vegetative bacteria and bacterial spores, respectively. Both dosages improved retention of immunoglobulin A (IgA), IgG, IgM, lactoferrin, cathepsin D, and elastase and activities of bile-salt-stimulated lipase and lysozyme compared with HoP. These UV-C doses caused minor reductions in α-tocopherol but not γ-tocopherol and no increases in lipid oxidation products. UV-C treatment is a promising approach for donor human milk processing.

Ultraviolet-C (UV-C) Effectiveness for Bacterial Decontamination in The Hospital Setting: A Systematic Review

Introduction: Bacteria are the most common agent reported to cause hospital-acquired infection (HAI) and nurses play a key role in achieving optimal decontamination. Ultraviolet-C (UV-C) is a promising candidate to reduce the bacteria infection burden. Therefore, this review aims to explore the UV-C application and its effectiveness in reducing bacteria contamination on various objects that can act as sources of HAI transmission. Methods: Searches were conducted on the PubMed, ScienceDirect, Scopus, and Cumulative Index to Nursing and Allied Health Literature databases. The inclusion criteria were randomized clinical trials, and non-randomized clinical intervention studies, written in English and published between January 2018 and March 2023. The search strategy used a population (P), intervention (I), comparator (C), and outcome (O) approach. Results: A total of 21 eligible studies were included in this review with four being related to decontaminating medical devices, two to personal equipment, nine to communication devices, and the remaining six to the environment. The exposure to UV-C radiation varies ranging from 24 s to 24 h (continuously) and it reduced the level of bacteria even up to 100%. Meanwhile, previously the objects were detected to be contaminated with pathogenic and resistant bacteria. Conclusion: UV-C exposure can be effectively used to decontaminate various objects in hospitals. However, special consideration should be given to semi-critical devices due to contact with mucosal tissue. Further studies are needed regarding the application of doses and duration of UV-C exposure to eliminate bacteria completely.

Far-UVC (222 nm) irradiation effectively inactivates ssRNA, dsRNA, ssDNA, and dsDNA viruses as compared togermicidal UVC (254 nm).

Ultraviolet-C (UVC) irradiation is being used as an effective approach for the disinfection of pathogenic viruses present in air, surfaces, and water. Recently, far-UVC radiation (222 nm) emitted by KrCl* (krypton-chloride) excimer lamps have been recommended for disinfecting high-risk public spaces to reduce the presence and transmission of infectious viruses owing to limited human health exposure risks as compared to germicidal UVC (254 nm). In this study, the UVC inactivation performances of individual filtered KrCl* excimer lamp (222 nm) and germicidal UVC lamp (254 nm) were determined against four viruses, bacteriophages MS2, Phi6, M13, and T4, having different genome compositions (ssRNA, dsRNA, ssDNA and dsDNA, respectively) and shapes (i.e., spherical (Phi6), linear (M13), and icosahedral (MS2 and T4)). Here, the disinfection efficacies of filtered KrCl* excimer lamp (222 nm) and germicidal UVC lamp (254 nm) were evaluated for highly concentrated virus droplets that mimic the virus-laden droplets released from the infected person and deposited on surfaces as fomites. Filtered KrCl* excimer (222 nm) showed significantly better inactivation against all viruses having different genome compositions and structures compared to germicidal UVC (254 nm). The obtained sensitivity against the filtered KrCl* excimer (222 nm) was found to be in the order, T4 > M13 > Phi6 > MS2 whereas for the germicidal UVC (254 nm) it was T4 > M13 > MS2 > Phi6. These results provide a strong basis to promote the use of filtered KrCl* excimer lamps (222 nm) in disinfecting contagious viruses and to limit the associated disease spread in public places and other high-risk areas.

Combined hurdle effects of pulsed electric field and ultraviolet-C irradiation on microbial load reduction and composition of hemeproteins from Asian seabass gills

The combined effects of two non-thermal technologies, namely pulsed electric field (PEF) and ultraviolet-C (UV–C) irradiation, on microbial load reduction and composition of crude hemeprotein extract (CHPE) from Asian seabass gills were investigated. PEF at two intensities (15 kV and 17.5 kV) for different times (0, 1, 2.5, 5 and 10 min) was employed to treat CHPE solution. Subsequently freeze-dried PEF treated powders were exposed to UV-C for varying durations (0, 15 and 30 min). Microbial community in gill and selected CHPE powders was also determined using next generation sequencing (NGS). PEF treatment effectively reduced the initial microbial load (8.0 log10 CFU/g) when high PEF intensity (17.5 kV) for longer treatment time (5 min) was employed, leading to microbial load reduction to 5.5 log10 CFU/g. However, prolonged PEF treatment adversely affected CHPE properties, as witnessed by the decreased heme iron content and alterations in protein patterns. Subsequent UV-C irradiation of freeze-dried PEF-treated CHPE powder for 15 min demonstrated a synergistic effect on further reduction of microbial counts to 3.0 log10 CFU/g. NGS analysis showed the dominance of Flavobacteriaceae families in the microbial community composition in gill, untreated CHPE powder and PEF-UV-C treated CHPE powder. Nevertheless, no Vibrio parahaemolyticus and other Vibrio spp. were detected in all samples. The study revealed the potential of combined non-thermal hurdle technologies, under appropriate conditions, in ensuring microbiological safety and maintaining quality of CHPE. CHPE powder could therefore be used for fortification in food products as an iron supplement to alleviate iron-deficient anemia.

Pilot randomized experimental study evaluating isopropyl alcohol and ultraviolet-C radiation in the disinfection of healthcare workers' smartphones

Smartphones in medical settings pose infection risks due to harbouring pathogenic bacteria. This pilot study assessed the effectiveness duration of sanitization methods, focusing on 70% isopropyl alcohol wipes and ultraviolet-C (UVC) boxes, aiming to obtain preliminary data on the reduction in total bacterial load 3h post-sanitization. A randomized monocentric trial with two intervention arms (wipes and UVC boxes) was designed. As participants, healthcare workers from three wards at Fondazione Policlinico Universitario 'A. Gemelli' IRCCS Hospital were recruited, stratified by ward, and block randomized within each ward to control confounders. Seventy-one healthcare workers, mostly nurses (62%) were included in the study. Initial bacterial load reduction was significant with both disinfection techniques, but after 3h both methods showed increased bacterial levels, with wipes displaying potentially higher residual efficacy (P=0.056). To adequately size a trial (89% power, significance level 0.05) for assessing the residual efficacy of alcohol-impregnated wipes compared with UVC boxes at 3h post-sanitization, 503 professionals per group were required. This study highlights the necessity for guidelines on hospital smartphone sanitization and educational initiatives for healthcare workers and patients. Further studies, adequately sized, are necessary to determine optimal sanitization intervals and assess pathogen transmission risks.

Ultraviolet C radiation on polypropylene: A potential way to reduce plastic pollution

This study investigates the application of ultraviolet C (UVC) radiation to extend the lifetime of healthcare items containing polypropylene (PP), particularly personal protective equipment (PPE). The main objectives involve assessing possible PP damage from UVC exposure and detecting UVC treatment within PP samples. FTIR spectroscopy and Raman spectroscopy reveal slight degradation in UVC-irradiated PP samples, demonstrating resilience post-treatment. Investigations using commercial thermoluminescence dosimeters (TLD-100, TLD-200, TLD-400 and GR-200) positioned under varying thicknesses of PP (0.20 and 0.80 mm) identify TLD-100 as a promising UVC detector. Conversely, TLD-200 and TLD-400 do not prove to be effective detectors, exhibiting similar behavior to the dosimeters without a plastic sample. And GR-200 does not possess the capability to differentiate between ionizing and non-ionizing components of UVC radiation. This research emphasizes the role of UVC to prolong the lifetime of healthcare items containing PP, thus aiding in efforts to reduce plastic pollution.