Action of benzalkonium chloride in different pH

Sarcopoterium spinosum (L.) is a medicinal plant traditionally used for the treatment of various diseases including cancer in the Near- and Middle East. The fractions and constituents of the ethanol extract of S. spinosum were screened for in vitro cytotoxic activities on Jurkat (acute T-lymphoblastic leukemia), HeLa (cervical adenocarcinoma), MCF-7 (mammary gland adenocarcinoma), Caco-2 (human colorectal adenocarcinoma), and MDA-MB-231 (mammary gland adenocarcinoma) cell lines using the MTT (3-(dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The ethanol extract was subsequently re-extracted with ethyl acetate and in its sub-fraction obtained by column chromatography three compounds (stachydrine, benzalkonium chloride and rutine) were the first time identified by nuclear magnetic resonance (NMR) analyses. The most active subfraction showed cytotoxic activity against HeLa, MCF-7, and Caco-2 cell lines. The three compounds mentioned, as standards of high-performance liquid chromatography (HPLC) quality, were studied individually and in combination. Cytotoxic activity observed might be due to the presence of benzalkonium chloride and rutin. Benzalkonium chloride showed the strongest growth suppression effect against HeLa cells (IC50 8.10−7 M) and MCF-7 cells (IC50 5.10−6 M). The mixture of stachydrine and benzalkonium chloride allowed a synergistic cytotoxic effect against all tested cancer and normal cells to be obtained. Anti-cancer activity of the plant extract of S. spinosum remains under-investigated, so this research describes how the three major compounds identified in the ethyl acetate extract can exert a significant dose dependent in vitro cytotoxicity.

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Accumulation and Phytotoxicity of Two Commercial Biocides in the Lichen Evernia prunastri and the Moss Brachythecium sp.

Stresses ◽

10.3390/stresses1020006 ◽

2021 ◽

Vol 1 (2) ◽

pp. 69-77

Author(s):

Andrea Vannini ◽

Giulia Canali ◽

Sergio Enrico Favero-Longo ◽

Stefano Loppi

Keyword(s):

Benzalkonium Chloride ◽

Photosynthetic Apparatus ◽

Model Species ◽

Evernia Prunastri ◽

Active Compounds ◽

Severe Impairment ◽

Over Time

This study investigated the accumulation and phytotoxicity of two commercial biocides widely used for the removal of biological colonization from monuments, namely Biotin T® (3%) and Preventol RI80® (2%), on lichen and moss model species, specifically, Evernia prunastri and Brachythecium sp. The active compounds, benzalkonium chloride (BAC) for Preventol RI80 and isothiazolinone (OIT) for Biotin T, were accumulated in similar amounts in both species without significant changes for up to 21 days. Both compounds caused a severe impairment of the photosynthetic apparatus of these species, without any recovery over time, although Biotin T showed a faster and stronger action, and the moss was more sensitive than the lichen. By shedding light on the accumulation of BAC and OIT in lichens and mosses and quantifying their effectiveness to photosynthetically devitalize these organisms, the obtained results are a useful comparison for the implementation of green alternative products for the control of biodeteriogens.

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Advanced Killing Potential of Thymol against a Time and Temperature Optimized Attached Listeria monocytogenes Population in Lettuce Broth

Biomolecules ◽

10.3390/biom11030397 ◽

2021 ◽

Vol 11 (3) ◽

pp. 397

Author(s):

Dimitra Kostoglou ◽

Parthena Tsaklidou ◽

Ioannis Iliadis ◽

Nikoletta Garoufallidou ◽

Georgia Skarmoutsou ◽

...

Keyword(s):

Listeria Monocytogenes ◽

Benzalkonium Chloride ◽

Planktonic Cells ◽

Antimicrobial Efficiency ◽

Fresh Vegetables ◽

Viable Bacteria ◽

Steel Surfaces ◽

Polymerase Chain ◽

Killing Action ◽

Foodborne Infections

Fresh vegetables and salads are increasingly implicated in outbreaks of foodborne infections, such as those caused by Listeria monocytogenes, a dangerous pathogen that can attach to the surfaces of the equipment creating robust biofilms withstanding the killing action of disinfectants. In this study, the antimicrobial efficiency of a natural plant terpenoid (thymol) was evaluated against a sessile population of a multi-strain L. monocytogenes cocktail developed on stainless steel surfaces incubated in lettuce broth, under optimized time and temperature conditions (54 h at 30.6 °C) as those were determined following response surface modeling, and in comparison, to that of an industrial disinfectant (benzalkonium chloride). Prior to disinfection, the minimum bactericidal concentrations (MBCs) of each compound were determined against the planktonic cells of each strain. The results revealed the advanced killing potential of thymol, with a concentration of 625 ppm (= 4 × MBC) leading to almost undetectable viable bacteria (more than 4 logs reduction following a 15-min exposure). For the same degree of killing, benzalkonium chloride needed to be used at a concentration of at least 20 times more than its MBC (70 ppm). Discriminative repetitive sequence-based polymerase chain reaction (rep-PCR) also highlighted the strain variability in both biofilm formation and resistance. In sum, thymol was found to present an effective anti-listeria action under environmental conditions mimicking those encountered in the salad industry and deserves to be further explored to improve the safety of fresh produce.

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Neutralization of the eye and skin irritant benzalkonium chloride using UVC radiation

Cutaneous and Ocular Toxicology ◽

10.1080/15569527.2021.1902339 ◽

2021 ◽

pp. 1-7

Author(s):

Manlong Xu ◽

Jacob G. Sivak ◽

David J. McCanna

Keyword(s):

Benzalkonium Chloride ◽

Uvc Radiation

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The Use of an Opacitometer to Compare the In Vitro Cornea Opacifying Effects of Timolol With and Without Benzalkonium Chloride

Alternatives to Laboratory Animals ◽

10.1177/026119299101900220 ◽

1991 ◽

Vol 19 (2) ◽

pp. 263-270

Author(s):

Haruyoshi Igarashi ◽

Yasunaga Katsuta ◽

Yoshiharu Nakazato ◽

Tohru Kawasaki

Keyword(s):

Benzalkonium Chloride ◽

Additive Effects ◽

Timolol Maleate ◽

Epithelial Surface ◽

Endothelial Surface ◽

Draize Test ◽

Corneal Opacities

We have evaluated a new in vitro opacitometer method as an alternative to the in vivo Draize test for ocular irritancy. Several concentrations of timolol maleate (timolol) with or without 0.005% benzalkonium chloride were applied to porcine isolated corneas which were either intact or with the epithelium, endothelium, or both epithelium and endothelium removed. Corneal opacities were measured using an opacitometer. In general, timolol with benzalkonium chloride caused a greater degree of opacity to develop in the cornea than did timolol alone. At the lower concentrations of timolol, the increased opacity probably represented additive effects of the two compounds. However, at the highest concentration of timolol (5 x 10 2M), there was an enhanced opacification in the presence of benzalkonium chloride, which may have been due to an increase in penetration, particularly through the epithelium. Timolol caused a greater degree of opacity to develop in the isolated intact porcine corneas when the drug was applied to the endothelial surface, than when applied to the epithelial surface or to both the epithelial and endothelial surfaces. However, timolol with benzalkonium chloride caused a greater degree of opacity in the intact cornea, when the drug was applied to both surfaces than when it was applied only to the epithelial or the endothelial surface.

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