scholarly journals Kinetic Modeling of Slightly Acidic Electrolyzed Water Decay Characteristics in Fresh Cabbage Disinfection Against Human Norovirus

2021 ◽  
Vol 12 ◽  
Author(s):  
Miran Kang ◽  
Boyeon Park ◽  
Ji-Hyoung Ha

To consistently disinfect fresh vegetables efficiently, the decay of disinfectants such as chlorine, electrolyzed oxidizing water (EOW), ozonated water, and plasma-activated water during the disinfection maintenance stage needs to be understood. The aim of our study was to evaluate the changes in the inactivation kinetics of slightly acidic electrolyzed water (SAEW) against human norovirus (HuNoV), based on the cabbage-to-SAEW ratio. After disinfection of fresh cabbage with disinfected SAEW solution, SAEW samples were collected and analyzed for physicochemical properties such as pH, available chlorine concentrations (ACCs), and oxidation-reduction potential (ORP). SAEW virucidal effects were evaluated. We confirmed the decay of post-disinfection SAEW solution and demonstrated the different patterns of the decay kinetic model for HuNoV GI.6 and GII.4. In addition, the goodness of fit of the tested models based on a lower Akaike information criterion, root-mean-square error (RMSE), and residual sum of squares (RSS) was close to zero. In particular, the change in both the HuNoV GI.6 and GII.4 inactivation exhibited a strong correlation with the changes in the ACC of post-disinfection SAEW. These findings demonstrate that physicochemical parameters of SAEW play a key role in influencing the kinetic behavior of changes in the disinfection efficiency of SAEW during the disinfection process. Therefore, to optimize the efficiency of SAEW, it is necessary to optimize the produce-to-SAEW ratio in future studies.

2001 ◽  
Vol 671 ◽  
Author(s):  
Kunkul Ryoo ◽  
Byeongdoo Kang

ABSTRACTA present semiconductor cleaning technology is based upon RCA cleaning technology which consumes vast amounts of chemicals and ultra pure water(UPW) and is the high temperature process. Therefore, this technology gives rise to the many environmental issues, and some alternatives such as functional water cleaning are being studied. The electrolyzed water was generated by an electrolysis system which consists of anode, cathode, and middle chambers. Oxidative water and reductive water were obtained in anode and cathode chambers, respectively. In case of NH4Clelectrolyte, the oxidation-reduction potential and pH for anode water(AW) and cathode water(CW) were measured to be +1050mV and 4.8, and -750mV and 10.0, respectively. AW and CW were deteriorated after electrolyzed, but maintained their characteristics for more than 40 minutes sufficiently enough for cleaning. Their deterioration was correlated with CO2 concentration changes dissolved from air. It was known that AW was effective for Cu removal, while CW was more effective for Fe removal. The particle distributions after various particle removal processes maintained the same pattern. In this work, RCA consumed about 9 chemicals, while EW did only 400ml HCl electrolyte or 600ml NH4Cl electrolyte. It was hence concluded that EW cleaning technology would be very effective for eliminating environment, safety, and health(ESH) issues in the next generation semiconductor manufacturing.


Food Research ◽  
2020 ◽  
Vol 4 (S6) ◽  
pp. 146-149
Author(s):  
N.S. Sulaiman ◽  
N.I. Khalid ◽  
E.M.H. Fauzi ◽  
N. Ab Aziz ◽  
N.A. Yusof ◽  
...  

The lab-scale electrolytic cell was designed to produce acidic and alkaline electrolyzed water for cleaning study. Electrolyzed water (EW) was produced by electrolysis of a dilute sodium chloride solution. The generation of free chlorine, pH and oxidation-reduction potential from the electrolysis process by the electrolytic cell were far from the expected value. Thus, the lab-scale electrolytic cell was revamped by using the acrylic slot to hold the electrode plate and a membrane holder without metal screws. This revamp work is to reduce the resistance for current flow with the aim to increase the value of chemical properties (pH, oxidation-reduction potential, free chlorine) for acidic and alkaline electrolyzed water. Findings have shown that the current was increased from 0.013A to 2.5A after the revamp process. As a result of the revamp, the value of pH, oxidationreduction potential and free chlorine for acidic electrolyzed water was increased by 1.7 times, 2.7 times, and 20 times higher than previous results respectively. While for alkaline electrolyzed water, the value of pH and oxidation-reduction potential was increased by 1.4 times and 6.2 times higher than previous results respectively.


2018 ◽  
Vol 81 (5) ◽  
pp. 860-869 ◽  
Author(s):  
MOHAMMAD SHAKHAWAT HUSSAIN ◽  
MINYEONG KWON ◽  
CHARLES NKUFI TANGO ◽  
DEOG HWAN OH

ABSTRACT This study examined the disinfection efficacy and mechanism of electrolyzed water (EW) on Bacillus cereus biofilms. B. cereus strains, ATCC 14579 and Korean Collection for Type Cultures (KCTC) 13153 biofilms, were formed on stainless steel (SS) and plastic slide (PS) coupons. Mature biofilms were treated with slightly acidic EW (SAEW), acidic EW (AEW), and basic EW (BEW). SAEW (available chlorine concentration, 25 ± 1.31 mg L−1; pH 5.71 ± 0.16; and oxidation reduction potential, 818 to 855 mV) reduced ATCC 14579 biofilms on plastic slides to below the detection limit within 30 s. However, biofilms on SS coupons showed a higher resistance to the SAEW treatment. When the disinfection activities of three types of EW on biofilms were compared, AEW showed a higher bactericidal activity, followed by SAEW and BEW. In contrast, BEW showed a significantly (P < 0.05) higher biofilm dispersal activity than AEW and SAEW. SAEW disinfection of the B. cereus biofilms was due to the disruption of the B. cereus plasma membrane. The higher resistance of biofilms formed on the SS coupon might be due to the higher number of attached cells and extracellular polymeric substances formation that reacts with the active chlorine ions, such as hypochlorous acid and hypochlorite ion of SAEW, which decreased the disinfection efficacy of SAEW. This study showed that the EW treatment effectively disinfected B. cereus biofilms, providing insight into the potential use of EW in the food processing industry to control the biofilm formation of B. cereus.


2018 ◽  
Vol 61 (1) ◽  
pp. 305-314 ◽  
Author(s):  
Zhangying Ye ◽  
Shuo Wang ◽  
Weishan Gao ◽  
Songjian Nan ◽  
Songming Zhu ◽  
...  

Abstract. This study investigated the suppressive effect and the inactivation mechanism of slightly acidic electrolyzed water (SAEW) on . The experiment compared different inhibition effects with SAEW and two antibiotics, gentamicin and norfloxacin. The conditions of pH of 6.5, oxidation-reduction potential (ORP) of 890 mV, available chlorine concentration (ACC) of 28 mg L-1 of SAEW, and volume ratios of 1:10, 1:15, and 1:20 were used. Using exposure times of 5 and 10 min to analyze the inactivation mechanism of SAEW from the perspectives of cell membrane permeability, cell nuclear morphology, cell fluorescence staining, and other aspects, the anti-infection effects of SAEW were tested using tilapia () culture experiments. SAEW had a stronger bacteriostasis effect than the antibiotics used. SAEW can inhibit the ability to reproduce, causing abnormal cell morphology and cell elongation. The cell volume was increased with a change in the membrane permeability. The cell nuclear morphology was changed, further inducing apoptosis. Based on study of tilapia in a control group, the organs (intestine, stomach, and liver) developed different degrees of infection. No obvious infection was observed in muscle samples. After SAEW treatment, SAEW showed a better antibacterial effect and improvement effects on the inflammation and structural damage induced by , which could be helpful in aquaculture application. Keywords: A. hydrophila, Antibiotics, Anti-infection, Cell apoptosis, Membrane permeability, Slightly acidic electrolyzed water.


2008 ◽  
Vol 71 (9) ◽  
pp. 1934-1947 ◽  
Author(s):  
D. HRICOVA ◽  
R. STEPHAN ◽  
C. ZWEIFEL

Electrolyzed water (EW) is gaining popularity as a sanitizer in the food industries of many countries. By electrolysis, a dilute sodium chloride solution dissociates into acidic electrolyzed water (AEW), which has a pH of 2 to 3, an oxidation-reduction potential of >1,100 mV, and an active chlorine content of 10 to 90 ppm, and basic electrolyzed water (BEW), which has a pH of 10 to 13 and an oxidation-reduction potential of −800 to −900 mV. Vegetative cells of various bacteria in suspension were generally reduced by >6.0 log CFU/ml when AEW was used. However, AEW is a less effective bactericide on utensils, surfaces, and food products because of factors such as surface type and the presence of organic matter. Reductions of bacteria on surfaces and utensils or vegetables and fruits mainly ranged from about 2.0 to 6.0 or 1.0 to 3.5 orders of magnitude, respectively. Higher reductions were obtained for tomatoes. For chicken carcasses, pork, and fish, reductions ranged from about 0.8 to 3.0, 1.0 to 1.8, and 0.4 to 2.8 orders of magnitude, respectively. Considerable reductions were achieved with AEW on eggs. On some food commodities, treatment with BEW followed by AEW produced higher reductions than did treatment with AEW only. EW technology deserves consideration when discussing industrial sanitization of equipment and decontamination of food products. Nevertheless, decontamination treatments for food products always should be considered part of an integral food safety system. Such treatments cannot replace strict adherence to good manufacturing and hygiene practices.


2001 ◽  
Vol 64 (5) ◽  
pp. 652-658 ◽  
Author(s):  
SHIGENOBU KOSEKI ◽  
KYOICHIRO YOSHIDA ◽  
SEIICHIRO ISOBE ◽  
KAZUHIKO ITOH

The disinfectant effect of acidic electrolyzed water (AcEW), ozonated water, and sodium hypochlorite (NaOCl) solution on lettuce was examined. AcEW (pH 2.6; oxidation reduction potential, 1140 mV; 30 ppm of available chlorine) and NaOCl solution (150 ppm of available chlorine) reduced viable aerobes in lettuce by 2 log CFU/g within 10 min. For lettuce washed in alkaline electrolyzed water (AlEW) for 1 min and then disinfected in AcEW for 1 min, viable aerobes were reduced by 2 log CFU/g. On the other hand, ozonated water containing 5 ppm of ozone reduced viable aerobes in lettuce 1.5 log CFU/g within 10 min. It was discovered that AcEW showed a higher disinfectant effect than did ozonated water significantly at P < 0.05. It was confirmed by swabbing test that AcEW, ozonated water, and NaOCl solution removed aerobic bacteria, coliform bacteria, molds, and yeasts on the surface of lettuce. Therefore, residual microorganisms after the decontamination of lettuce were either in the inside of the cellular tissue, such as the stomata, or making biofilm on the surface of lettuce. Biofilms were observed by a scanning electron microscope on the surface of the lettuce treated with AcEW. Moreover, it was shown that the spores of bacteria on the surface were not removed by any treatment in this study. However, it was also observed that the surface structure of lettuce was not damaged by any treatment in this study. Thus, the use of AcEW for decontamination of fresh lettuce was suggested to be an effective means of controlling microorganisms.


2020 ◽  
Vol 83 (10) ◽  
pp. 1838-1843 ◽  
Author(s):  
ZACHARY BLOCK ◽  
ALIETA EYLES ◽  
ROSS CORKREY ◽  
ROGER STANLEY ◽  
TOM ROSS ◽  
...  

ABSTRACT Neutral electrolyzed water (NEW) is an oxidizing sanitizer that can be made locally on-site; it is often stored in a ready-to-use format to accumulate the large volumes required for periodic or seasonal use. The shelf stability of NEW sanitizer was, therefore, assessed under various storage conditions to guide the development of protocols for its industrial application. To that end, fresh NEW with an available chlorine concentration (ACC) of 480 mg/L, pH 6.96, and oxidation reduction potential (ORP) of 916 mV was stored under different conditions. These were open or sealed polypropylene bottles, three different surface area–to–volume (SA:V) ratios (0.9, 1.7, and 8.7), and two temperatures (4 and 25°C). NEW stored at 4°C was significantly more stable than NEW stored at 25°C; ACC and pH decreased by 137 mg/L and 0.7, respectively, whereas ORP increased by 23 mV, after 101 days of storage. At 25°C, ACC decreased to <0.01 mg/L after 52 days in bottles with a SA:V ratio of 8.7, with a similar decrease after 101 days in bottles with a SA:V ratio of 1.7. However, pH decreased by up to 3.7 pH units, and ORP increased by up to 208 mV. The antimicrobial efficacy of “aged” electrolyzed oxidizing (EO) water with different ACC and ORP, but the same pH (i.e., 3.4 ± 0.2), was evaluated against Escherichia coli and Listeria innocua to determine any differences in residual antimicrobial activity. EO water with an ACC of ≥7 mg/L and an ORP of 1,094 mV caused a reduction of at least 4.7 log, whereas EO water with nondetectable ACC and considerably high ORP (716 mV) had little antimicrobial effect (<1-log reduction). Results from this study indicate that the efficacy of NEW as a sanitizer for large-scale applications such as horticulture can be maintained for at least 3 months when it is stored in closed containers with low SA:V ratio at low temperatures. HIGHLIGHTS


Plant Disease ◽  
2003 ◽  
Vol 87 (6) ◽  
pp. 712-718 ◽  
Author(s):  
M. R. Bonde ◽  
S. E. Nester ◽  
N. W. Schaad ◽  
R. D. Frederick ◽  
D. G. Luster

Acidic electrolyzed water (AEW) is a germicidal product of electrolysis of a dilute solution (e.g., 0.4% vol/vol) of sodium chloride. This solution can be used to disinfest wheat seed or soil samples being tested for teliospores of Tilletia indica, causal agent of Karnal bunt, without risk of damaging the teliospores. The AEW used in this study had a pH of 2.5 to 2.8 and oxidation-reduction potential of approximately 1,130 mV. In simulations of routine extractions of wheat seed to detect teliospores of T. indica, the effectiveness of a 30-min AEW treatment was compared with a 2-min 0.4% sodium hypochlorite (NaOCl) treatment to eradicate bacteria and nonsmut fungi. Each treatment reduced bacterial and fungal populations in wheat seed extracts by 6 to 7 log10 units when determined on 2% water agar with antibiotics. Reductions of 5 log10 units or more were observed on other media. NaOCl and AEW also were very effective at eliminating bacteria and fungi from soil extracts. In studies to detect and quantitate T. indica teliospores in soil, AEW was nearly 100% effective at eliminating all nonsmut organisms. Free chlorine levels in AEW were very low, suggesting that compounds other than those with chlorine play a significant role in sanitation by AEW. The low pH of AEW was shown to contribute substantially to the effectiveness of AEW to reduce microorganisms. A standardized protocol is described for a 30-min AEW treatment of wheat seed washes or soil extracts to eliminate contaminating microorganisms. A significant advantage of the use of AEW over NaOCl is that, with AEW, teliospore germination is not reduced and usually is stimulated, whereas teliospore germination declines after contact with NaOCl. The protocol facilitates detection and enumeration of viable teliospores of T. indica in wheat seed or soil and the isolation of pure cultures for identification by polymerase chain reaction. The germicidal effects of AEW, as demonstrated in this study, illustrate the potential of AEW as an alternative to presently used seed disinfestants.


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