scholarly journals Effects of ultraviolet-C on the spores of Bacillus subtilis and Bacillus velezensis suspension in phosphate buffered saline with their structural and molecular analysis using Raman-AFM imaging

2020 ◽  
Vol 2 (7A) ◽  
Author(s):  
James Elegbeleye ◽  
Ramon Gervilla ◽  
Artur Roig-Sagues ◽  
Elna Buys
Keyword(s):  
Bacillus Subtilis ◽  
Flow Cytometric Analysis ◽  
Plate Count ◽  
Bacillus Velezensis ◽  
Afm Imaging ◽  
Ultraviolet C ◽  
A Cell ◽  
And Control ◽  
Syto 9 ◽  
Uv C

Bacterial spores are of concern in food processing due to their ubiquity and resistance. This study seeks to determine the effect of ultraviolet C (UV-C) in the inactivation of spores of Bacillus subtilis and Bacillus velezensis that can result in enzymatic spoilage in foods using PBS as the suspension medium. Purified spore samples were treated under 1 pass in a UV-C reactor using 10 mL of spore inoculum with one dose of the radiation (410 mJ/cm2) for 10secs at room temperature. Aliquots of the treated samples were plated on tryptone soy agar supplemented with 0.6% glucose and the colonies counted. Flow cytometry analysis was done using 500 μL of both treated and control samples with a cell concentration of a ≥106 CFU/ml with propidium iodide (15 μM) and SYTO 9 (500 nM) used as live/dead stains. Samples were processed for microscopy (SEM and Raman-AFM Imaging). The maximum lethality is 2.5 for B. velezensis and the minimum is 0.1 for B. subtilis. Microscopic imaging of treated spores shows significant morphological disruption of the spore structure. The Raman spectroscopy analysis reveals the B. subtilis isolates to have the highest concentrations of dipicolnic acid (Ca+2DPA) as well as other compounds belonging to other functional groups. Flow cytometric analysis of treated spores reveals sub-populations unaccounted for by plate count. UV-C shows a promising application in the inactivation of resistant spores during processing of liquid foods such as milk.

scholarly journals USE OF DIFFERENT PROBIOTICS FOR PREVENTION OF VIBRIOSIS DISEASE ON TIGER SHRIMP LARVAE REARED IN FIBERGLASS TANKSUSE OF DIFFERENT PROBIOTICS FOR PREVENTION OF VIBRIOSIS DISEASE ON TIGER SHRIMP LARVAE REARED IN FIBERGLASS TANKS

2018 ◽  
Vol 13 (2) ◽  
pp. 95 ◽  
Author(s):  
Nurbaya Nurbaya ◽  
Muharijadi Atmomarsono
Keyword(s):  
Bacillus Subtilis ◽  
Survival Rate ◽  
Sea Water ◽  
Ammonia Nitrogen ◽  
Plate Count ◽  
Powder Form ◽  
Liquid Form ◽  
Brevibacillus Laterosporus ◽  
Tiger Shrimp ◽  
And Control

To counter disease problems caused by vibriosis in shrimp hatchery, this recent study used three different probiotics to be tested on tiger shrimp (Penaeus monodon) postlarvae. The study arranged four treatments as follows: A: a combination of three liquid-form probiotics Brevibacillus laterosporus BT951, Bacillus subtilis BM12, and B. licheniformis BM58; B: a combination of three powder-form probiotics Brevibacillus laterosporus BT951, Bacillus subtilis BM12, and B. licheniformis BM58; C: a commercial powder probiotic containing Bacillus subtilis; and D: control (without probiotic), each treatment with three replications. This study was set up in a completely randomized design experiment using twelve fiberglass tanks filled with 750 L sterile sea water and stocked with 30,000 nauplii in the Awarange shrimp hatchery of the Research Institute for Brackishwater Aquaculture and Fisheries Extension Installation in Barru. Variables observed in this study were the survival rate of the shrimp postlarvae at the end of the experiment, total vibrio count (TBV) and total plate count of common bacteria (TPC) in the culture water. The results showed that the survival rate of tiger shrimp applied either in liquid (A: 61.5±4.7%) or powder form (B: 48.6±6.8%), and control (without probiotic) (D: 51.2±4.4%) were not significantly different (P>0.05). However, survival rates in these three treatments differed (P<0.05) with that of the commercial probiotic (C: 21.7±9.9%). TBV/TPC ratio in the tank waters treated with the commercial probiotic (2.26-37.52%) was much higher than that of the liquid form probiotic (0.86-1.98%), powder form probiotic (1.25-8.37%), and control (1.93-2.84%). Ammonia-nitrogen in treatment C (1.462-2.989 mg/L) was relatively higher than that of in treatment A (1.595-2.435 mg/L), treatment B (1.644-2.115 mg/L), and treatment D (1.051-1.858 mg/L).

scholarly journals Effectiveness of Ultraviolet-C Room Disinfection on Preventing Healthcare-Associated Clostridioides difficile Infection

2020 ◽  
Vol 41 (S1) ◽  
pp. s33-s33
Author(s):  
Michihiko Goto ◽  
Erin Balkenende ◽  
Gosia Clore ◽  
Rajeshwari Nair ◽  
Loretta Simbartl ◽  
...  
Keyword(s):  
Acute Care ◽  
Acute Care Hospitals ◽  
Incidence Rates ◽  
Positive Test ◽  
Negative Binomial Regression Model ◽  
Test Results ◽  
Clostridioides Difficile ◽  
Ultraviolet C ◽  
Healthcare Associated ◽  
Uv C

Background: Enhanced terminal room cleaning with ultraviolet C (UVC) disinfection has become more commonly used as a strategy to reduce the transmission of important nosocomial pathogens, including Clostridioides difficile, but the real-world effectiveness remains unclear. Objectives: We aimed to assess the association of UVC disinfection during terminal cleaning with the incidence of healthcare-associated C. difficile infection and positive test results for C. difficile within the nationwide Veterans Health Administration (VHA) System. Methods: Using a nationwide survey of VHA system acute-care hospitals, information on UV-C system utilization and date of implementation was obtained. Hospital-level incidence rates of clinically confirmed hospital-onset C. difficile infection (HO-CDI) and positive test results with recent healthcare exposures (both hospital-onset [HO-LabID] and community-onset healthcare-associated [CO-HA-LabID]) at acute-care units between January 2010 and December 2018 were obtained through routine surveillance with bed days of care (BDOC) as the denominator. We analyzed the association of UVC disinfection with incidence rates of HO-CDI, HO-Lab-ID, and CO-HA-LabID using a nonrandomized, stepped-wedge design, using negative binomial regression model with hospital-specific random intercept, the presence or absence of UVC disinfection use for each month, with baseline trend and seasonality as explanatory variables. Results: Among 143 VHA acute-care hospitals, 129 hospitals (90.2%) responded to the survey and were included in the analysis. UVC use was reported from 42 hospitals with various implementation start dates (range, June 2010 through June 2017). We identified 23,021 positive C. difficile test results (HO-Lab ID: 5,014) with 16,213 HO-CDI and 24,083,252 BDOC from the 129 hospitals during the study period. There were declining baseline trends nationwide (mean, −0.6% per month) for HO-CDI. The use of UV-C had no statistically significant association with incidence rates of HO-CDI (incidence rate ratio [IRR], 1.032; 95% CI, 0.963–1.106; P = .65) or incidence rates of healthcare-associated positive C. difficile test results (HO-Lab). Conclusions: In this large quasi-experimental analysis within the VHA System, the enhanced terminal room cleaning with UVC disinfection was not associated with the change in incidence rates of clinically confirmed hospital-onset CDI or positive test results with recent healthcare exposure. Further research is needed to understand reasons for lack of effectiveness, such as understanding barriers to utilization.Funding: NoneDisclosures: None

scholarly journals Ultraviolet-C as a Viable Reprocessing Method for Disposable Masks and Filtering Facepiece Respirators

Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 801
Author(s):  
Talita Nicolau ◽  
Núbio Gomes Filho ◽  
Andrea Zille
Keyword(s):  
Literature Review ◽  
Systematic Literature Review ◽  
Personal Protective Equipment ◽  
State Of The Art ◽  
Protective Equipment ◽  
Multiple Methods ◽  
Ultraviolet C ◽  
Single Use ◽  
Uv C ◽  
New Strategies

In normal conditions, discarding single-use personal protective equipment after use is the rule for its users due to the possibility of being infected, particularly for masks and filtering facepiece respirators. When the demand for these protective tools is not satisfied by the companies supplying them, a scenario of shortages occurs, and new strategies must arise. One possible approach regards the disinfection of these pieces of equipment, but there are multiple methods. Analyzing these methods, Ultraviolet-C (UV-C) becomes an exciting option, given its germicidal capability. This paper aims to describe the state-of-the-art for UV-C sterilization in masks and filtering facepiece respirators. To achieve this goal, we adopted a systematic literature review in multiple databases added to a snowball method to make our sample as robust as possible and encompass a more significant number of studies. We found that UV-C’s germicidal capability is just as good as other sterilization methods. Combining this characteristic with other advantages makes UV-C sterilization desirable compared to other methods, despite its possible disadvantages.

scholarly journals Inactivation of Candida auris and Candida albicans by Ultraviolet-C

2020 ◽  
Vol 41 (S1) ◽  
pp. s292-s292
Author(s):  
William Rutala ◽  
Hajime Kanamori ◽  
Maria Gergen ◽  
Emily Sickbert-Bennett ◽  
David Jay Weber
Keyword(s):  
Infection Prevention ◽  
Antifungal Drugs ◽  
Candida Auris ◽  
Healthcare Facilities ◽  
Environmental Surfaces ◽  
Route Of Transmission ◽  
Indirect Exposure ◽  
Ultraviolet C ◽  
Severe Infections ◽  
Uv C

Background:Candida auris is an emerging fungal pathogen that is often resistant to major classes of antifungal drugs. It is considered a serious global health threat because it has caused severe infections with frequent mortality in over a dozen countries. C. auris can survive on healthcare environmental surfaces for at least 7 days, and it causes outbreaks in healthcare facilities. C. auris has an environmental route of transmission. Thus, infection prevention strategies, such as surface disinfection and room decontamination technologies (eg, ultraviolet [UV-C] light), will be essential to controlling transmission. Unfortunately, data are limited regarding the activity of UV-C to inactivate this pathogen. In this study, a UV-C device was evaluated for its antimicrobial activity against C. auris and C. albicans. Methods: We tested the antifungal activity of a single UV-C device using the vegetative bacteria cycle, which delivers a reflected dose of 12,000 µW/cm2. This testing was performed using Formica sheets (7.6 × 7.6 cm; 3 × 3 inches). The carriers were inoculated with C. auris or C. albicans and placed horizontal on the surface or vertical (ie, perpendicular) to the vertical UV-C lamp and at a distance from 1. 2 m (~4 ft) to 2.4 m (~8 ft). Results: Direct UV-C, with or without FCS (log10 reduction 4.57 and 4.45, respectively), exhibited a higher log10 reduction than indirect UV-C for C. auris (log10 reduction 2.41 and 1.96, respectively), which was statistically significant (Fig. 1 and Table 1). For C. albicans, although direct UV-C had a higher log10 reduction (log10 reduction with and without FCS, 5.26 and 5.07, respectively) compared to indirect exposure (log10 reduction with and without FCS, 3.96 and 3.56, respectively), this difference was not statistically significant. The vertical UV had statistically higher log10 reductions than horizontal UV against C. auris and C. albicans with FCS and without FCS. For example, for C. auris with FCS the log10 reduction for vertical surfaces was 4.92 (95% CI 3.79, 6.04) and for horizontal surfaces the log10 reduction was 2.87 (95% CI, 2.36–3.38). Conclusions:C. auris can be inactivated on environmental surfaces by UV-C as long as factors that affect inactivation are optimized (eg, exposure time). These data and other published UV-C data should be used in developing cycle parameters that prevent contaminated surfaces from being a source of acquisition by staff or patients of this globally emerging pathogen.Funding: NoneDisclosures: None

scholarly journals Minimal, superficial DNA damage in human skin from filtered far‐ultraviolet‐C (UV‐C)

2021 ◽  
Author(s):  
R.P. Hickerson ◽  
M.J. Conneely ◽  
S.K. Hirata Tsutsumi ◽  
K. Wood ◽  
D.N. Jackson ◽  
...  
Keyword(s):  
Dna Damage ◽  
Human Skin ◽  
Ultraviolet C ◽  
Far Ultraviolet ◽  
Uv C

scholarly journals Combined Application of Rhizosphere Bacteria with Endophytic Bacteria Suppresses Root Diseases and Increases Productivity of Black Pepper (Piper nigrum L.)

Agriculture ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 15
Author(s):  
Sy Dinh Nguyen ◽  
Thi Huyen Trang Trinh ◽  
Trung Dzung Tran ◽  
Tinh Van Nguyen ◽  
Hoang Van Chuyen ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Endophytic Bacteria ◽  
Growth Promotion ◽  
Black Pepper ◽  
Rhizosphere Bacteria ◽  
Growth And Yield ◽  
Piper Nigrum ◽  
Bacillus Velezensis ◽  
Root Knot Nematode ◽  
Central Highland

Black pepper (Piper nigrum L.) is one of the most important crops and global demand continues to increase, giving it a high export value. However, black pepper cultivation has been seriously affected by a number of pathogenic diseases. Among them, “quick wilt” caused by Phytophthora sp., “slow decline” caused by Fusarium sp., and root-knot nematode Meloidogyne sp. have a serious negative effect on black pepper growth and productivity. There have been different chemical and biological methods applied to control these diseases, but their effectiveness has been limited. The aim of this research was to evaluate different combinations of rhizosphere bacteria and endophytic bacteria isolated from black pepper farms in the Central Highland of Vietnam for their ability to suppress pathogens and promote black pepper growth and yield. Formula 6, containing the strains Bacillus velezensis KN12, Bacillus amyloliquefaciens DL1, Bacillus velezensis DS29, Bacillus subtilis BH15, Bacillus subtilis V1.21 and Bacillus cereus CS30 exhibited the largest effect against Phytophthora and Fusarium in the soil and in the roots of black pepper. These bio-products also increased chlorophyll a and b contents, which led to a 1.5-fold increase of the photosynthetic intensity than the control formula and a 4.5% increase in the peppercorn yield (3.45 vs. 3.30 tons per hectare for the control). Our results suggest that the application of rhizosphere and endophytic bacteria is a promising method for disease control and growth-promotion of black pepper.

The analysis of surface saccharide profiles through fluorescein-labelled lectins in a rat pancreatic tissue with established metabolic syndrome model

2018 ◽  
Vol 44 (1) ◽  
pp. 98-104
Author(s):  
Yosun Mater ◽  
Sule Beyhan-Ozdas
Keyword(s):  
Metabolic Syndrome ◽  
Metabolic Diseases ◽  
Pancreatic Tissue ◽  
Control Group ◽  
High Fructose Diet ◽  
Tissue Sections ◽  
Membrane Surfaces ◽  
High Fructose ◽  
A Cell ◽  
And Control

Abstract“Glycans”, which are generally referred as oligosaccharides and polysaccharides, are structures that are present on all cellular surfaces with proteins and lipids being attached to their basic chain structures. Many studies in the field of glycobiology have identified the various and complicated biological roles of these glycans which make them perfect molecules to use in labelling and selecting body cells specifically. This study aims at analyzing the modifications in saccharide units of glycans on a cell membrane surfaces of the pancreatic tissue of rats to which normal and metabolic syndrome (MetS) are established. To this end, a MetS model was created through a high fructose diet in Spraque Dawley breed of rats and the pancreatic tissue sections of the group with MetS and control group animals were evaluated comparatively. The targeted saccharide units were examined with Fluorescent Microscope by using two different Fluorescein (FITC) labelled lectins, namely Maackia amurensis-1 lectin [FITC-(MAL-I)] and the Wheat Germ Agglutinin (FITC-WGA). It was observed that FITC-MAL-1-labelled Galβ4GlcNAc units did not change much due to high- fructose diet. On the other hand, more GlcNAc, Neu5Ac and β-GlcNAc units which are labelled with FITC-WGA lectin increase in numbers in pancreatic sections of high fructose diet, compared to control group. Thus, a rapid and specific labelling method, which can identify surface saccharide sequences specifically, was developed. The method can be used in early diagnosis and/or treatment for metabolic diseases.

scholarly journals Insights into the role of lipoteichoic acids in Bacillus subtilis- a new function for MprF

2021 ◽  
Author(s):  
Aurelie Guyet ◽  
Amirah Alofi ◽  
Richard A Daniel
Keyword(s):  
Bacillus Subtilis ◽  
Cell Envelope ◽  
Cellular Level ◽  
Penicillin Binding Proteins ◽  
Class A ◽  
Peptidoglycan Synthesis ◽  
A Cell ◽  
Antimicrobial Peptide Resistance ◽  
Lipoteichoic Acids

In Bacillus subtilis, the cell is protected from the environment by a cell envelope, which comprises of layers of peptidoglycan that maintain the cell shape and anionic teichoic acids polymers whose biological function remains unclear. In B. subtilis, loss of all Class A Penicillin-Binding Proteins (aPBPs) which function in peptidoglycan synthesis is conditionally lethal. Here we show that this lethality is associated with an alteration of the lipoteichoic acids (LTA) and the accumulation of the major autolysin LytE in the cell wall. We provide the first evidence that the length and abundance of LTA acts to regulate the cellular level of LytE. Importantly, we identify a novel function for the aminoacyl-phosphatidylglycerol synthase MprF which acts to modulate LTA biosynthesis in B. subtilis and in the pathogen Staphylococcus aureus. This finding has implications for our understanding of antimicrobial peptide resistance (particularly daptomycin) in clinically relevant bacteria and MprF-associated virulence in pathogens, such as methicillin resistant S. aureus.

scholarly journals Improving and Comparing Probiotic Plate Count Methods by Analytical Procedure Lifecycle Management

2021 ◽  
Vol 12 ◽  
Author(s):  
M. L. Jane Weitzel ◽  
Christina S. Vegge ◽  
Marco Pane ◽  
Virginia S. Goldman ◽  
Binu Koshy ◽  
...  
Keyword(s):  
Analytical Procedure ◽  
Health Benefit ◽  
Viable Cell ◽  
Plate Count ◽  
Data Set ◽  
Colony Forming Units ◽  
Specific Factors ◽  
And Control ◽  
Lifecycle Management ◽  
Development Laboratory

Probiotics are live microorganisms that confer a health benefit to the host when administered in adequate amounts. This definition links probiotic efficacy to microbial viability. The current gold standard assay for probiotic potency is enumeration using classical microbiology plating-based procedures, yielding results in colony-forming units (CFU). One drawback to plating-based procedures is high variability due to intrinsic and extrinsic uncertainties. These uncertainties make comparison between analytical procedures challenging. In this article, we provide tools to reduce measurement uncertainty and strengthen the reliability of probiotic enumerations by using analytical procedure lifecycle management (APLM). APLM is a tool that uses a step-by-step process to define procedure performance based on the concept that the reportable value (final CFU result) must be fit for its intended use. Once the procedure performance is defined, the information gathered through APLM can be used to evaluate and compare procedures. Here, we discuss the theory behind applying APLM and give practical information about its application to CFU enumeration procedures for probiotics using a simulated example and data set. Data collected in a manufacturer’s development laboratory is included to support application of the concept. Implementation of APLM can lead to reduced variability by identifying specific factors (e.g., the dilution step) with significant impact on the variability and providing insights to procedural modifications that lead to process improvement. Understanding and control of the analytical procedure is improved by using these tools. The probiotics industry can confidently apply the information and analytical results generated to make decisions about processes and formulation, including overage requirements. One benefit of this approach is that companies can reduce overage costs. More reliable procedures for viable cell count determinations will improve the quality evaluation of probiotic products, and hence manufacturing procedures, while ensuring that products deliver clinically demonstrated beneficial doses.

scholarly journals Mapping of UV-C dose and SARS-CoV-2 viral inactivation across N95 respirators during decontamination

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alisha Geldert ◽  
Alison Su ◽  
Allison W. Roberts ◽  
Guillaume Golovkine ◽  
Samantha M. Grist ◽  
...  
Keyword(s):  
Optical Simulation ◽  
Pathogen Inactivation ◽  
Viral Inactivation ◽  
Flexible Form ◽  
Measurement Tools ◽  
Ultraviolet C ◽  
N95 Respirators ◽  
Uv C ◽  
Dose Difference

AbstractDuring public health crises like the COVID-19 pandemic, ultraviolet-C (UV-C) decontamination of N95 respirators for emergency reuse has been implemented to mitigate shortages. Pathogen photoinactivation efficacy depends critically on UV-C dose, which is distance- and angle-dependent and thus varies substantially across N95 surfaces within a decontamination system. Due to nonuniform and system-dependent UV-C dose distributions, characterizing UV-C dose and resulting pathogen inactivation with sufficient spatial resolution on-N95 is key to designing and validating UV-C decontamination protocols. However, robust quantification of UV-C dose across N95 facepieces presents challenges, as few UV-C measurement tools have sufficient (1) small, flexible form factor, and (2) angular response. To address this gap, we combine optical modeling and quantitative photochromic indicator (PCI) dosimetry with viral inactivation assays to generate high-resolution maps of “on-N95” UV-C dose and concomitant SARS-CoV-2 viral inactivation across N95 facepieces within a commercial decontamination chamber. Using modeling to rapidly identify on-N95 locations of interest, in-situ measurements report a 17.4 ± 5.0-fold dose difference across N95 facepieces in the chamber, yielding 2.9 ± 0.2-log variation in SARS-CoV-2 inactivation. UV-C dose at several on-N95 locations was lower than the lowest-dose locations on the chamber floor, highlighting the importance of on-N95 dose validation. Overall, we integrate optical simulation with in-situ PCI dosimetry to relate UV-C dose and viral inactivation at specific on-N95 locations, establishing a versatile approach to characterize UV-C photoinactivation of pathogens contaminating complex substrates such as N95s.

Sign in / Sign up

Export Citation Format

Share Document