scholarly journals A Double-Edged Sword of Surfactant Effect on Hydrophobic Surface Broccoli Leaf as a Model Plant: Promotion of Pathogenic Microbial Contamination and Improvement to Disinfection Efficiency of Ozonated Water

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 679
Author(s):  
Hyun Jong Song ◽  
Min Hwan Kim ◽  
Kang-Mo Ku

Pathogenic microbial contamination is significantly influenced by the crop surface properties and surfactant use, which are crucial factors for the postharvest washing process. However, there is little information on the interaction between surfactant and food pathogens on food crops. Thus, this study (1) investigated whether the attachment of Salmonella increases as pesticides denature epicuticular wax crystals and (2) tested if the antibacterial effect of ozonated water can be improved on waxy produce surfaces by adding surfactant to ozonated water. As a result, significantly lower levels of Salmonella Typhimurium attached to waxy leaf surfaces than they did to glossy and pesticide-treated waxy leaf surfaces (3.28 as opposed to 4.10 and 4.32 Log colony forming units (CFU)/cm2, respectively), suggesting that the pesticide containing a surfactant application increased the attachment of S. Typhiumurium on waxy leaf surfaces. There was no significant washing effect on waxy leaf surfaces washed with ozonated water. On the other hand, S. Typhimurium were not detected on waxy leaf surfaces after washing with surfactant-added ozonated water.

2008 ◽  
Vol 56 (8) ◽  
pp. 644 ◽  
Author(s):  
Simona Dragota ◽  
Markus Riederer

The present study describes fine structure and chemical composition of the epicuticular leaf waxes of three Araucariaceae species. The leaf surfaces of samples from greenhouse-grown juvenile trees of Araucaria araucana K.Koch and Agathis robusta F.Muell. were investigated by scanning electron microscopy (SEM) and compared with data for a young greenhouse-grown Wollemia nobilis W.G.Jones, K.D.Hill & J.M.Allen cutting characterised earlier. The chemical compositions of the epicuticular waxes selectively removed from the adaxial and abaxial leaf surfaces of A. araucana, A. robusta and W. nobilis were studied by gas chromatography combined with mass spectroscopy (GC–MS). The main components of the leaf cuticular waxes of A. araucana, A. robusta and W. nobilis are members of the following three major compound classes: n-alkanes, secondary alcohols and alkane diols. It was shown earlier that the latter two classes contribute to the formation of the tubular epicuticular-wax crystals on the leaf surfaces. The present comparative study also revealed differences in the crystalline microstructure and chemical composition of the epicuticular leaf waxes among the three species.


Author(s):  
Can Banu Uygun ◽  
Özbay Gizem ◽  
Altundal Hatice ◽  
Durmazpinar Parla Meva ◽  
Kitiki Burak ◽  
...  

Author(s):  
Silvia Oktavia Nur Yudiastuti ◽  
Rizza Wijaya

The objective of this article was to study the effect of washing edamame using ozonated water to reduce residual chlorine contained in edamame through a continuous washing process. Chlorine residue in edamame was caused by the use of fertilizers and pesticides that contain chlorine compounds. The research method used was descriptive explanatory research consist of two treatment levels of ozonation time (0, 10, and 15 minutes) and ozone contact time (0, 12, 18, and 24 minutes) which were repeated twice. The residual chlorine and pesticide concentrations were calculated using the titration method. Based on research results, ozone can reduce chlorine in edamame. The lowest detected chlorine was in edamame which had been washed using ozone water with an ozonation time of 15 minutes with the amount of chlorine reduced by 56%. The longer the contact time, the greater the amount of reduced chlorine and the lower the concentration of ozone remaining in the washing water. Based on the research results, a brief conclusion that can be explained was ozone could reduce chlorine in edamame caused by fertilizer and disinfectant overuse until 50%.


2013 ◽  
Vol 2 (4) ◽  
pp. 1 ◽  
Author(s):  
Gabriele Messina ◽  
Emma Ceriale ◽  
Sandra Burgassi ◽  
Carmela Russo ◽  
Chiara Defranceschi ◽  
...  

Background: Computers and telephones are ubiquitous in the hospital and have been shown to be contaminated with potentially pathogenic microorganism. The aim of the study was to determine microbial contamination on computer keyboards and telephone handsets and the effectiveness of a disinfecting technique (DT). Methods: A matched cross-over study, involving an overall of 50 computer keyboards and 50 telephone handsets, was conducted in three hospitals, located in the Local Health Area of Siena (Italy) before and after the use of an innovative DT consisting of a malleable-elastic compound, containing ethanol, which adheres to surfaces, removes dirt and disinfects. Total bacterial count was evaluated and several types of bacteria and fungi were researched pre- and post- use of the DT. Non parametric tests: Wilcoxon signed rank and Mann Whitney, were used, when appropriate. Results: The DT was effective in disinfecting the objects. In fact, Colony-Forming Units (CFUs) decreased to zero in most comparisons. All the comparisons showed significant differences (p<0.001) after the DT, both for computer keyboards and telephone handsets. The only exception was found for molds in telephones (p=0.062). Keyboards emerged to be dirtier than telephones handsets (p<0.05) for several types of bacteria. Conclusions: The data suggest that microbial contamination of keyboards and telephones is considerable. These objects can be a vehicle for Health Care-Associated Infections HAIs and their disinfection should not be neglected. The DT showed to be appropriate for the disinfecting purpose.


2003 ◽  
Vol 14 (1) ◽  
pp. 55-57 ◽  
Author(s):  
Maria Cristina Monteiro de Souza-Gugelmin ◽  
Carolina Della Torre Lima ◽  
Sergio Narciso Marques de Lima ◽  
Henis Mian ◽  
Izabel Yoko Ito

The quality of water in a dental unit is of considerable importance because patients and dental staff are regularly exposed to water and aerosol generated from the dental unit. The aim of this study was to evaluate the occurrence of microbial contamination in dental unit waterlines. Water samples were collected aseptically from the waterlines (reservoir, triple-syringe, high-speed) of 15 dental units. After serial dilution to 1:10(6) in APHA, the samples were seeded by the pour-plate technique and cultured in plate count agar (Difco) for 48 h at 32ºC. Analysis was based on the number of colony forming units (CFU). The Wilcoxon non-parametric test indicated that the levels of water contamination were highest in the triple-syringe (13 of 15) and in the high-speed (11 of 15); both levels were higher than those of the water reservoir. There was no significant statistical difference between the level of contamination in the triple-syringe and the high-speed as determined by the Mann-Whitney test [p(H0) = 40.98%; Z = - 0.2281]. Because biofilm forms on solid surfaces constantly bathed by liquid where microorganisms are present, these results indicate that the water in the dental unit may be contaminated by biofilm that forms in these tubules.


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