Thermal, Chemical, and Photocatalytic Inactivation of Lactobacillus plantarum Bacteriophages

2009 ◽  
Vol 72 (5) ◽  
pp. 1012-1019 ◽  
Author(s):  
MARIÁNGELES BRIGGILER MARCÓ ◽  
GRACIELA L. DE ANTONI ◽  
JORGE A. REINHEIMER ◽  
ANDREA QUIBERONI
Keyword(s):  
Thermal Resistance ◽  
Lactobacillus Plantarum ◽  
Sodium Hypochlorite ◽  
Peracetic Acid ◽  
Skim Milk ◽  
Thermal Treatments ◽  
Glucose Medium ◽  
Industrial Plants ◽  
Complete Inactivation ◽  
Photocatalytic Inactivation

The effect of several biocides, thermal treatments, and photocatalysis on the viability of four Lactobacillus plantarum phages was investigated. Times to achieve 99% inactivation (T99) of phages at 63, 72, and 90°C were evaluated in four suspension media: deMan Rogosa Sharpe broth, reconstituted skim milk, a commercial EM-glucose medium, and Tris magnesium gelatin buffer. The four phages studied were highly resistant to 63°C(T99 > 45 min); however, counts < 10 PFU/ml were achieved by heating at 90°C for 5 min. Higher thermal resistance at 72°C was observed when reconstituted skim milk and EM-glucose medium were assayed. Peracetic acid (0.15%, vol/vol) was an effective biocide for the complete inactivation of all phages studied within 5 min of exposure. Sodium hypochlorite (800 ppm) inactivated the phages completely within 30 min. Ethanol (100%) did not destroy phage particles even after 45 min. Isopropanol did not have any effect on phage viability. Phage counts < 50 PFU/ml were obtained within 180 min of photocatalytic treatment. The results obtained in this work are important for establishing adequate methods for inactivating phages in industrial plants and laboratory environments.

Inactivation of Lactobacillus helveticus Bacteriophages by Thermal and Chemical Treatments

1999 ◽  
Vol 62 (8) ◽  
pp. 894-898 ◽  
Author(s):  
A. QUIBERONI ◽  
V. B. SUÁREZ ◽  
J. A. REINHEIMER
Keyword(s):  
Sodium Hypochlorite ◽  
Peracetic Acid ◽  
High Titer ◽  
Skim Milk ◽  
Lactobacillus Helveticus ◽  
Thermal Treatments ◽  
Laboratory Equipment ◽  
Chemical Treatments ◽  
Complete Inactivation ◽  
Dairy Plant

The effect of several biocides and thermal treatments on the viability of four Lactobacillus helveticus phages was investigated. Times to achieve 99% inactivation of phages at 63°C and 72°C in three suspension media were calculated. The three suspension media were tris magnesium gelatin buffer (10 mM Tris-HCl, 10 mM MgSO4, and 0.1% wt/vol gelatin), reconstituted skim milk sterile reconstituted commercial nonfat dry skim milk, and Man Rogosa Sharpe broth. The thermal resistance depended on the phage considered, but a treatment of 5 min at 90°C produced a total inactivation of high titer suspensions of all phages studied. The results obtained for the three tested media did not allow us to establish a clear difference among them, since some phages were more heat resistant in Man Rogosa Sharpe broth and others in tris magnesium gelatin buffer. From the investigation on biocides, we established that sodium hypochlorite at a concentration of 100 ppm was very effective in inactivating phages. The suitability of ethanol 75%, commonly used to disinfect utensils and laboratory equipment, was confirmed. Isopropanol turned out to be, in general, less effective than ethanol at the assayed concentrations. In contrast, peracetic acid (0.15%) was found to be an effective biocide for the complete inactivation of all phages studied after 5 min of exposure. The results allowed us to establish a basis for adopting the most effective thermal and chemical treatments for inactivating phages in dairy plant and laboratory environments.

Inactivation of Lactobacillus Virulent Bacteriophage by Thermal and Chemical Treatments

2018 ◽  
Vol 81 (10) ◽  
pp. 1673-1678 ◽  
Author(s):  
XIA CHEN ◽  
YING LIU ◽  
SHIYU CHAI ◽  
JING GUO ◽  
WENRU WU
Keyword(s):  
Sodium Hypochlorite ◽  
Peracetic Acid ◽  
Additional Data ◽  
Skim Milk ◽  
Thermal Treatments ◽  
Log Reduction ◽  
Chemical Treatments ◽  
Bacteriophage P2 ◽  
De Man ◽  
Minimum Heat

ABSTRACT The uses of thermal and chemical treatments were evaluated with respect to the inactivation of the Lactobacillus virulent bacteriophage P2. Thermal treatments consisted of heating the phage at 63, 72, and 90°C in three broth media: de Man Rogosa Sharpe broth, reconstituted skim milk, and Tris magnesium gelatin buffer. Chemical treatments evaluated were ethanol, isopropanol, sodium hypochlorite, and peracetic acid at various concentrations. Phage P2 was completely inactivated in 20 and 5 min at 72 and 90°C, respectively. Reconstituted skim milk and de Man Rogosa Sharpe broth provided optimum and minimum heat protection, respectively. Only sodium hypochlorite at 400 and 800 ppm completely inactivated the phage in 50 and 30 min, respectively. Treatment with 100% ethanol and isopropanol resulted in only a ca. 5.1-log reduction. Peracetic acid at the highest concentration used (0.45%) resulted in only a 1.40-log reduction of the phage within 60 min. These results provide additional data for establishing effective methods of controlling phage contamination in dairy and laboratory environments.

Effectiveness of Thermal Treatments and Biocides in the Inactivation of Argentinian Lactococcus lactis Phages

2002 ◽  
Vol 65 (11) ◽  
pp. 1756-1759 ◽  
Author(s):  
VIVIANA B. SUÁREZ ◽  
JORGE A. REINHEIMER
Keyword(s):  
Lactococcus Lactis ◽  
Sodium Hypochlorite ◽  
Chemical Resistance ◽  
High Titer ◽  
Skim Milk ◽  
The Other ◽  
Thermal Treatments ◽  
Viral Particles ◽  
Protective Medium ◽  
The Times

The thermal and chemical resistance levels of four autochthonal bacteriophages of Lactococcus lactis subsp. lactis, isolated from cheese processes, was investigated. The times required to obtain 99% inactivation of phages (T99) at 63 and 72°C in three suspension media (M17 broth, reconstituted commercial nonfat skim milk, and Tris magnesium gelatin buffer) were determined. Thermal resistance was dependent on the phage studied, and the results of this study demonstrate that pasteurization treatments used in dairy industries may leave viable viral particles in milk. It was possible to determine that M17 broth was generally the least protective medium, while phosphate buffer was the most protective one. Peracetic acid (0.15%, vol/vol) was the most effective viricidal agent, with exposures of 5 min being sufficient to inactivate high-titer phage suspensions (>106 PFU/ml). To achieve total inactivation (<10 PFU/ml) of viral suspensions, sodium hypochlorite was effective at 100 ppm for only two phages, while the other two phages needed concentrations of 200 and 300 ppm. Ethanol at concentrations of 100 and 75% proved to be very efficient in inactivating phages, but isopropanol was not effective against them.

An Assessment of Pasteurization Treatment of Water, Media, and Milk with Respect to Bacillus Spores†

2005 ◽  
Vol 68 (4) ◽  
pp. 751-757 ◽  
Author(s):  
JOHN S. NOVAK ◽  
JEFFREY CALL ◽  
PEGGY TOMASULA ◽  
JOHN B. LUCHANSKY
Keyword(s):  
Thermal Resistance ◽  
Skim Milk ◽  
Brain Heart Infusion ◽  
Brain Heart Infusion Broth ◽  
Complete Inactivation ◽  
Milk Pasteurization ◽  
Water Media ◽  
Bacillus Spp ◽  
Bacillus Spores ◽  
Synthetic Media

This study evaluated the ability of spore-forming Bacillus spp. to resist milk pasteurization conditions from 72 to 150°C. Spores from the avirulent surrogate Sterne strain of Bacillus anthracis, as well as a representative strain of a common milk contaminant that is also a pathogen, Bacillus cereus ATCC 9818, were heated at test temperatures for up to 90 min in dH2O, brain heart infusion broth, or skim milk. In skim milk, characteristic log reductions (log CFU per milliliter) for B. anthracis spores were 0.45 after 90 min at 72°C, 0.39 after 90 min at 78°C, 8.10 after 60 min at 100°C, 7.74 after 2 min at 130°C, and 7.43 after 0.5 min at 150°C. Likewise, log reductions (log CFU per milliliter) for viable spores of B. cereus ATCC 9818 in skim milk were 0.39 after 90 min at 72°C, 0.21 after 60 min at 78°C, 7.62 after 60 min at 100°C, 7.37 after 2 min at 130°C, and 7.53 after 0.5 min at 150°C. No significant differences (P < 0.05) in thermal resistance were observed for comparisons of spores heated in dH2O or brain heart infusion broth compared with results observed in skim milk for either strain tested. However, spores from both strains were highly resistant (P < 0.05) to the pasteurization temperatures tested. As such, pasteurization alone would not ensure complete inactivation of these spore-forming pathogens in dH2O, synthetic media, or skim milk.

Thermal and Chemical Inactivation of Indigenous Streptococcus thermophilus Bacteriophages Isolated from Argentinian Dairy Plants

2000 ◽  
Vol 63 (4) ◽  
pp. 509-515 ◽  
Author(s):  
A. G. BINETTI ◽  
J. A. REINHEIMER
Keyword(s):  
Sodium Hypochlorite ◽  
Peracetic Acid ◽  
Chemical Resistance ◽  
Skim Milk ◽  
Streptococcus Thermophilus ◽  
Fast Inactivation ◽  
Effective Agent ◽  
Chemical Inactivation ◽  
Chemical Treatments ◽  
Practical Implications

Thermal and chemical resistance of five autochthonal bacteriophages of Streptococcus thermophilus, isolated from Cuartirolo cheese wheys and yogurt, was investigated. Times to obtain 99% inactivation of phages (T99)at63°C and 72°C in three suspension media (enriched tryptic soy broth, reconstituted commercial nonfat skim milk, and tris magnesium gelatin buffer) were determined. The thermal resistance was dependent on the phages studied but not detectable counts (<10 PFU/ml) were only achieved by heating at 90°C during 5 min. The data obtained for the three assayed media did not permit verifying significant differences among them. Sodium hypochlorite (100 ppm) provided a fast inactivation of bacteriophage particles (<10 PFU/ml after 5 min). Ethanol, at concentrations of 75% and 100%, was also effective for phage destruction. Isopropanol was slightly less effective than ethanol at the same concentrations. Peracetic acid (0.15%) was also a very effective agent for phage inactivation. The results showed that these autochthonal bacteriophages were not completely inactivated neither by normal pasteurization treatments nor by some biocides commonly used in disinfection, except sodium hypochlorite and peracetic acid. The practical implications of these findings have pointed out the necessity of recognizing the importance of establishing adequate conditions to assure effective thermal and chemical treatments in dairy plants and laboratory environments.

Antimicrobial activity of Chlorhexidine, Peracetic acid and Sodium hypochlorite/etidronate irrigant solutions againstEnterococcus faecalisbiofilms

2015 ◽  
Vol 48 (12) ◽  
pp. 1188-1193 ◽  
Author(s):  
M. T. Arias-Moliz ◽  
R. Ordinola-Zapata ◽  
P. Baca ◽  
M. Ruiz-Linares ◽  
E. García García ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Sodium Hypochlorite ◽  
Peracetic Acid

Leakage of Endotoxins through the Endotoxin Retentive Filter: An in vitro Study

2022 ◽  
pp. 1-9
Author(s):  
Hiroshi Nozaki ◽  
Yoshihiro Tange ◽  
Yoji Inada ◽  
Takashi Uchino ◽  
Nakanobu Azuma
Keyword(s):  
Sodium Hypochlorite ◽  
Peracetic Acid ◽  
In Vitro Study ◽  
Dialysis Fluid ◽  
High Concentration ◽  
Membrane Pores ◽  
Polyether Sulfone ◽  
Repeated Use ◽  
High Concentrations

<b><i>Introduction:</i></b> Ultrapurification of dialysis fluid has enabled highly efficient dialysis treatments. Online hemodiafiltration is one such treatment that uses a purified dialysis fluid as a supplemental fluid. In this method, an endotoxin retentive filter (ETRF) is used in the final step of dialysis fluid purification, with the aim of preventing leakage of endotoxins. Sodium hypochlorite and peracetic acid are used as disinfecting agents for the dialysis fluid pipes containing the ETRF; however, the effects of these agents on ETRF membrane pores have not been fully clarified. <b><i>Methods:</i></b> Water permeability (flux) and endotoxin permeability were assessed in 3 types of ETRFs made with different membrane materials: polyester polymer alloy (PEPA), polyether sulfone (PES), and polysulfone (PS). High-concentration sodium hypochlorite and 2 types of peracetic acid were used as disinfecting agents, and the changes in flux and the endotoxin sieving coefficient (SC) were measured. <b><i>Results:</i></b> After repeated use of high concentrations of sodium hypochlorite and peracetic acid, the PEPA and PES ETRFs did not permit passage of endotoxins, regardless of their flux. However, in the PS ETRF, the flux and endotoxin SC increased with the number of cleaning cycles. No differences were observed according to the concentration of peracetic acid disinfecting agents. <b><i>Conclusion:</i></b> PEPA and PES ETRFs completely prevent endotoxin leakage and can be disinfected at concentrations higher than the conventionally recommended concentration without affecting pore expansion. Even new PS ETRFs have low levels of endotoxin leakage, which increase after disinfection cycles using sodium hypochlorite and peracetic acid.

Comparative Evaluation of the Sterilization Effect of Six Kinds of Commercial Disinfectants against Four Pathogenic Bacteria

2021 ◽  
Author(s):  
Wenxia Wang ◽  
Xiaoting Liang ◽  
Junxia Zheng ◽  
Qi He
Keyword(s):  
Sodium Hypochlorite ◽  
Peracetic Acid ◽  
Pathogenic Bacteria ◽  
Antibacterial Effect ◽  
Antibacterial Properties ◽  
Water Soluble ◽  
Absolute Ethanol ◽  
Dilution Method ◽  
Clostridium Sporogenes ◽  
Sterilization Effect

Abstract In this work, we systematically investigate the sterilization effect of six kinds of commonly used commercial disinfectants, including the DuPont Virkon disinfectant, peracetic acid disinfectant, sodium hypochlorite, bromogeramine disinfectant, water-soluble allicin, and absolute ethanol, against the Escherichia coli, Staphylococcus aureus, Monilia albican and Clostridium sporogenes. The inhibition zone was used to qualitatively determine the antibacterial effects of the six disinfectants, and then the minimum two-fold dilution method was used to quantitatively determine the minimum inhibitory concentration and minimum bactericidal concentration of the six disinfectants on the four pathogens. The result illustrated that the antibacterial effect of peracetic acid disinfectant is the best, and clostridium sporogenes is the most sensitive to it, followed by bromogermine disinfectant, which can inhibit the four pathogenic bacteria at the concentration recommended by the manufacturer. The antibacterial effect of DuPont Virkon disinfectant, sodium hypochlorite, water-soluble allicin and absolute ethanol is not as good as expected, and cannot inhibit the four kinds of pathogenic bacteria at the recommended concentration. In summary, the antibacterial effect of peracetic acid disinfectant is the strongest, followed by the bromogermine disinfectant, DuPont Virkon disinfectant, sodium hypochlorite and water-soluble allicin. The absolute ethanol exhibits the worst antibacterial properties.

Evaluation of a Sporicidal Peracetic Acid/Hydrogen Peroxide–Based Daily Disinfectant Cleaner

2014 ◽  
Vol 35 (11) ◽  
pp. 1414-1416 ◽  
Author(s):  
Abhishek Deshpande ◽  
Thriveen S. C. Mana ◽  
Jennifer L. Cadnum ◽  
Annette C. Jencson ◽  
Brett Sitzlar ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Staphylococcus Aureus ◽  
Clostridium Difficile ◽  
Sodium Hypochlorite ◽  
Peracetic Acid ◽  
Infect Control Hosp ◽  
Organic Load ◽  
Methicillin Resistant

OxyCide Daily Disinfectant Cleaner, a novel peracetic acid/hydrogen peroxide–based sporicidal disinfectant, was as effective as sodium hypochlorite for in vitro killing of Clostridium difficile spores, methicillin-resistant Staphylococcus aureus, and vancomcyin-resistant enterococci. OxyCide was minimally affected by organic load and was effective in reducing pathogen contamination in isolation roomsInfect Control Hosp Epidemiol 2014;35(11):1414–1416

Biofilm Formation and Biocides Sensitivity of Pseudomonas marginalis Isolated from a Maple Sap Collection System

2006 ◽  
Vol 69 (10) ◽  
pp. 2411-2416 ◽  
Author(s):  
L. LAGACÉ ◽  
M. JACQUES ◽  
A. A. MAFU ◽  
D. ROY
Keyword(s):  
Sodium Hypochlorite ◽  
Peracetic Acid ◽  
Biofilm Formation ◽  
Planktonic Cells ◽  
Collection System ◽  
Biofilm Growth ◽  
Biofilm Production ◽  
Different Temperatures ◽  
Maple Sap ◽  
Scanning Electron

The susceptibility of planktonic and biofilm cells of Pseudomonas marginalis toward four commonly used biocides at different temperatures (15 and 30°C) and biofilm growth times (24 and 48 h) was assessed. Using the MBEC biofilm device, biofilm production in maple sap was shown to be highly reproducible for each set of conditions tested. Biofilm formation was influenced by growth temperature and time. A temperature of 15°C and incubation time of 24 h yielded fewer CFU per peg and showed fewer adhered cells and typical biofilm structures, based on scanning electron microscopy observations as compared with other conditions. Minimal biofilm eradication concentration values for P. marginalis were significantly greater (P &lt; 0.001) than were MBCs for planktonic cells and for every biocide tested, with the exception of minimal biofilm eradication concentration values for peracetic acid at 15°C and 24 h. Sodium hypochlorite and peracetic acid sanitizers were able to eliminate P. marginalis biofilms at lower concentrations as compared with hydrogen peroxide– and quaternary ammonium– based sanitizers (P &lt; 0.001). According to the results obtained, sodium hypochlorite and peracetic acid sanitizers would be more appropriate for maple sap collection system sanitation.

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