{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T14:07:45Z","timestamp":1776089265346,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2019,11,5]],"date-time":"2019-11-05T00:00:00Z","timestamp":1572912000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Antimicrobial photodynamic therapy (aPDT) has been shown as a promising technique to inactivate foodborne bacteria, without inducing the development of bacterial resistance. Knowing that addition of inorganic salts, such as potassium iodide (KI), can modulate the photodynamic action of the photosensitizer (PS), we report in this study the antimicrobial effect of eosin (EOS) and rose bengal (RB) combined with KI against Salmonella enterica serovar Typhimurium and Staphylococcus aureus. Additionally, the possible development of bacterial resistance after this combined aPDT protocol was evaluated. The combination of EOS or RB, at all tested concentrations, with KI at 100 mM, was able to efficiently inactivate S. Typhimurium and S. aureus. This combined approach allows a reduction in the PS concentration up to 1000 times, even against one of the most common foodborne pathogenics, S. Typhimurium, a gram-negative bacterium which is not so prone to inactivation with xanthene dyes when used alone. The photoinactivation of S. Typhimurium and S. aureus by both xanthenes with KI did not induce the development of resistance. The low price of the xanthene dyes, the non-toxic nature of KI, and the possibility of reducing the PS concentration show that this technology has potential to be easily transposed to the food industry.<\/jats:p>","DOI":"10.3390\/antibiotics8040211","type":"journal-article","created":{"date-parts":[[2019,11,5]],"date-time":"2019-11-05T06:47:57Z","timestamp":1572936477000},"page":"211","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["The Remarkable Effect of Potassium Iodide in Eosin and Rose Bengal Photodynamic Action against Salmonella Typhimurium and Staphylococcus aureus"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3061-6669","authenticated-orcid":false,"given":"Adriele R.","family":"Santos","sequence":"first","affiliation":[{"name":"Postgraduate Program in Food Science, State University of Maring\u00e1, Maring\u00e1 87020-900, Brazil"}]},{"given":"Andr\u00e9ia F. P.","family":"Batista","sequence":"additional","affiliation":[{"name":"Postgraduate Program in Food Science, State University of Maring\u00e1, Maring\u00e1 87020-900, Brazil"}]},{"given":"Ana T. P. C.","family":"Gomes","sequence":"additional","affiliation":[{"name":"Department of Biology and CESAM, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7953-8166","authenticated-orcid":false,"given":"Maria da Gra\u00e7a P. M. S.","family":"Neves","sequence":"additional","affiliation":[{"name":"QOPNA&amp; LAQV-REQUIMTE and Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4423-3802","authenticated-orcid":false,"given":"Maria Amparo F.","family":"Faustino","sequence":"additional","affiliation":[{"name":"QOPNA&amp; LAQV-REQUIMTE and Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8422-8664","authenticated-orcid":false,"given":"Adelaide","family":"Almeida","sequence":"additional","affiliation":[{"name":"Department of Biology and CESAM, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Noboru","family":"Hioka","sequence":"additional","affiliation":[{"name":"Department of Chemistry, State University of Maring\u00e1, Maring\u00e1 87020-900, Brazil"}]},{"given":"Jane M. G.","family":"Mikcha","sequence":"additional","affiliation":[{"name":"Department of Clinical Analysis and Biomedicine, State University of Maring\u00e1, Maring\u00e1 87020-900, Brazil"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1936","DOI":"10.1016\/j.foodres.2009.09.013","article-title":"Environmental impact of novel thermal and non-thermal technologies in food processing","volume":"43","author":"Pereira","year":"2010","journal-title":"Food Res. Int."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"S3","DOI":"10.1016\/j.ijfoodmicro.2010.01.021","article-title":"Food-borne diseases\u2014The challenges of 20 years ago still persist while new ones continue to emerge","volume":"139","author":"Newell","year":"2010","journal-title":"Int. J. Food Microbiol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"667","DOI":"10.1080\/1040841X.2018.1491528","article-title":"Photodynamic inactivation as an emergent strategy against foodborne pathogenic bacteria in planktonic and sessile states","volume":"44","author":"Silva","year":"2018","journal-title":"Crit. Rev. Microbiol."},{"key":"ref_4","unstructured":"European Food Safety Authority (2019, September 08). European Food Safety Authority Food-Borne Zoonotic Diseases. Available online: https:\/\/www.efsa.europa.eu\/en\/topics\/topic\/foodborne-zoonotic-diseases."},{"key":"ref_5","unstructured":"World Health Organization (2019, September 08). Food Safety. Available online: http:\/\/www.who.int\/en\/news-room\/fact-sheets\/detail\/food-safety."},{"key":"ref_6","unstructured":"US Food and Drug Administration (2019, September 08). What You Need to Know About Foodborne Illnesses, Available online: https:\/\/www.fda.gov\/food\/consumers\/what-you-need-know-about-foodborne-illnesses."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1016\/j.cofs.2019.04.002","article-title":"Klebsiella pneumonia carbapenemase (KPC), methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant Enterococcus spp. (VRE) in the food production chain and biofilm formation on abiotic surfaces","volume":"26","author":"Alonso","year":"2019","journal-title":"Curr. Opin. Food Sci."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1158","DOI":"10.5897\/AJMRx12.014","article-title":"The challenges of foodborne pathogens and antimicrobial chemotherapy: A global perspective","volume":"7","author":"Nyenje","year":"2013","journal-title":"Afr. J. Microbiol. Res."},{"key":"ref_9","unstructured":"Centers for Disease Control and Prevention (2019, September 08). Centers for Disease Control and Prevention Antibiotic\/Antimicrobial Resistance (AR\/AMR), Available online: https:\/\/www.cdc.gov\/drugresistance\/food.html."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"152","DOI":"10.1016\/j.jgar.2018.10.005","article-title":"Prevalence, multidrug resistance and molecular typing of methicillin-resistant Staphylococcus aureus (MRSA) in retail meat from Punjab, India","volume":"16","author":"Zehra","year":"2019","journal-title":"J. Glob. Antimicrob. Resist."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1016\/j.ijfoodmicro.2017.03.001","article-title":"Methicillin-resistant and-susceptible Staphylococcus aureus from retail meat in Denmark","volume":"249","author":"Tang","year":"2017","journal-title":"Int. J. Food Microbiol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"2697","DOI":"10.3389\/fmicb.2017.02697","article-title":"Prevalence, virulence genes and antimicrobial resistance profiles of Salmonella serovars from retail beef in Selangor, Malaysia","volume":"8","author":"Thung","year":"2017","journal-title":"Front. Microbiol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"132","DOI":"10.1016\/j.foodcont.2016.01.024","article-title":"Contamination of post-harvest poultry products with multidrug resistant Staphylococcus aureus in Maryland-Washington DC metro area","volume":"65","author":"Teramoto","year":"2016","journal-title":"Food Control"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"947","DOI":"10.4315\/0362-028X.JFP-16-407","article-title":"Prevalence and antimicrobial resistance of Salmonella isolates from chicken carcasses in retail markets in Yangon, Myanmar","volume":"80","author":"Moe","year":"2017","journal-title":"J. Food Protect."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"534","DOI":"10.1142\/S1088424619500408","article-title":"Advances in aPDT based on the combination of a porphyrinic formulation with potassium iodide: Effectiveness on bacteria and fungi planktonic\/biofilm forms and viruses","volume":"23","author":"Vieira","year":"2019","journal-title":"J. Porphyr. Phthalocyanines"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"267","DOI":"10.3389\/fmicb.2016.00267","article-title":"Effect of photodynamic therapy on the virulence factors of Staphylococcus aureus","volume":"7","author":"Bartolomeu","year":"2016","journal-title":"Front. Microbiol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1659","DOI":"10.1039\/c1pp05097d","article-title":"Mechanisms of photodynamic inactivation of a gram-negative recombinant bioluminescent bacterium by cationic porphyrins","volume":"10","author":"Tavares","year":"2011","journal-title":"Photochem. Photobiol. Sci."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"198","DOI":"10.1016\/j.lwt.2016.07.037","article-title":"Photodynamic inactivation of foodborne and food spoilage bacteria by curcumin","volume":"76","author":"Penha","year":"2017","journal-title":"LWT Food Sci. Technol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1617","DOI":"10.1111\/jam.13727","article-title":"Photodynamic inactivation of foodborne bacteria by eosin Y","volume":"124","author":"Bonin","year":"2018","journal-title":"J. Appl. Microbiol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1230","DOI":"10.1111\/php.13104","article-title":"Xanthene dyes and green LED for the inactivation of foodborne pathogens in planktonic and biofilm states","volume":"95","author":"Silva","year":"2019","journal-title":"Photochem. Photobiol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1007\/s00284-015-0827-5","article-title":"Photodynamic inactivation mediated by erythrosine and its derivatives on foodborne pathogens and spoilage bacteria","volume":"71","author":"Yassunaka","year":"2015","journal-title":"Curr. Microbial."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"415","DOI":"10.1016\/j.foodchem.2018.08.042","article-title":"Effects of curcumin-based photodynamic treatment on the storage quality of fresh-cut apples","volume":"274","author":"Tao","year":"2019","journal-title":"Food Chem."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1016\/j.foodres.2018.05.042","article-title":"Photodynamic inactivation of Burkholderia cepacia by curcumin in combination with EDTA","volume":"111","author":"Hu","year":"2018","journal-title":"Food Res. Int."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"80","DOI":"10.1016\/j.dyepig.2014.05.016","article-title":"A new insight on nanomagnet-porphyrin hybrids for photodynamic inactivation of microorganisms","volume":"110","author":"Alves","year":"2014","journal-title":"Dyes Pigments"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1221","DOI":"10.4155\/fmc.15.59","article-title":"Photodynamic inactivation of bacteria: Finding the effective targets","volume":"7","author":"Almeida","year":"2015","journal-title":"Future Med. Chem."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Mesquita, M.Q., Dias, C.J., Neves, M.G.P.M.S., Almeida, A., and Faustino, M.A.F. (2018). Revisiting current photoactive materials for antimicrobial photodynamic therapy. Molecules, 23.","DOI":"10.3390\/molecules23102424"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1016\/j.pdpdt.2018.04.009","article-title":"Is the chlorophyll derivative Zn(II)e6Me a good photosensitizer to be used in root canal disinfection?","volume":"22","author":"Diogo","year":"2018","journal-title":"Photodiagn. Photodyn. Ther."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"498","DOI":"10.3389\/fmicb.2017.00498","article-title":"Antimicrobial photodynamic therapy against endodontic Enterococcus faecalis and Candida albicans mono and mixed biofilms in the presence of photosensitizers: A comparative study with classical endodontic irrigants","volume":"8","author":"Diogo","year":"2017","journal-title":"Front. Microbiol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1387","DOI":"10.1111\/php.12331","article-title":"Photodynamic inactivation of bacterial and yeast biofilms with a cationic porphyrin","volume":"90","author":"Beirao","year":"2014","journal-title":"Photochem. Photobiol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"278","DOI":"10.1016\/j.antiviral.2011.06.007","article-title":"Evaluation of resistance development and viability recovery by a non-enveloped virus after repeated cycles of aPDT","volume":"91","author":"Costa","year":"2011","journal-title":"Antivir. Res."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Silva, A.F., Borges, A., Freitas, C.F., Hioka, N., Mikcha, J.M.G., and Simoes, M. (2018). Antimicrobial photodynamic inactivation mediated by rose bengal and erythrosine is effective in the control of food-related bacteria in planktonic and biofilm states. Molecules, 23.","DOI":"10.3390\/molecules23092288"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"626","DOI":"10.1039\/c3pp50195g","article-title":"Photodynamic inactivation of multidrug-resistant bacteria in hospital wastewaters: Influence of residual antibiotics","volume":"13","author":"Almeida","year":"2014","journal-title":"Photochem. Photobiol. Sci."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"790","DOI":"10.1111\/php.12645","article-title":"Nanostructured polymeric micelles carrying xanthene dyes for photodynamic evaluation","volume":"92","author":"Pellosi","year":"2016","journal-title":"Photochem. Photobiol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1016\/j.jphotochemrev.2015.05.002","article-title":"Enhancing photodynamic therapy of refractory solid cancers: Combining second-generation photosensitizers with multi-targeted liposomal delivery","volume":"23","author":"Weijer","year":"2015","journal-title":"J. Photochem. Photobiol. C"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"30","DOI":"10.1016\/j.jphotochem.2014.04.015","article-title":"Interaction of eosin and its ester derivatives with aqueous biomimetic micelles: Evaluation of photodynamic potentialities","volume":"287","author":"Pellosi","year":"2014","journal-title":"J. Photochem. Photobiol. A"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"2665","DOI":"10.3389\/fmicb.2018.02665","article-title":"An insight into the potentiation effect of potassium iodide on aPDT efficacy","volume":"9","author":"Vieira","year":"2018","journal-title":"Front. Microbiol."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1059","DOI":"10.1080\/14787210.2017.1397512","article-title":"Potentiation of antimicrobial photodynamic inactivation by inorganic salts","volume":"15","author":"Hamblin","year":"2017","journal-title":"Expert Rev. Anti Infect. Ther."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1016\/j.jphotobiol.2017.10.036","article-title":"Potentiation by potassium iodide reveals that the anionic porphyrin TPPS4 is a surprisingly effective photosensitizer for antimicrobial photodynamic inactivation","volume":"178","author":"Huang","year":"2018","journal-title":"J. Photochem. Photobiol. B"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"5203","DOI":"10.1128\/AAC.00019-15","article-title":"Bacterial photodynamic inactivation mediated by methylene blue and red light is enhanced by synergistic effect of potassium iodide","volume":"59","author":"Vecchio","year":"2015","journal-title":"Antimicrob. Agents Chemother."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"320","DOI":"10.1021\/acsinfecdis.7b00004","article-title":"Potassium iodide potentiates broad-spectrum antimicrobial photodynamic inactivation using photofrin","volume":"3","author":"Huang","year":"2017","journal-title":"ACS Infect. Dis."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"e00467-17","DOI":"10.1128\/AAC.00467-17","article-title":"Potassium iodide potentiates antimicrobial photodynamic inactivation mediated by rose bengal in in vitro and in vivo studies","volume":"61","author":"Wen","year":"2017","journal-title":"Antimicrob. Agents Chemother."},{"key":"ref_42","unstructured":"Food and Drug Administration (2001). Guidance Potassium Iodide as a Thyroid Blocking Agent in Radiation Emergencies, Food and Drug Administration."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"402","DOI":"10.1111\/1541-4337.12418","article-title":"Perspectives and trends in the application of photodynamic inactivation for microbiological food safety","volume":"18","author":"Ghate","year":"2019","journal-title":"Compr. Rev. Food Sci. Food Saf."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"e12988","DOI":"10.1111\/jfpe.12988","article-title":"Efficacy of photoactivated curcumin to decontaminate food surfaces under blue light emitting diode","volume":"42","author":"Aurum","year":"2019","journal-title":"J. Food Process. Eng."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1016\/j.jphotobiol.2011.06.011","article-title":"Microbial control of food-related surfaces: Na-Chlorophyllin-based photosensitization","volume":"105","author":"Luksiene","year":"2011","journal-title":"J. Photochem. Photobiol. B"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1016\/j.jphotochem.2012.04.012","article-title":"Singlet oxygen dosimetry using uric acid as a chemical probe: Systematic evaluation","volume":"238","author":"Rabello","year":"2012","journal-title":"J. Photochem. Photobiol. A"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"7257","DOI":"10.1038\/s41598-018-25365-0","article-title":"Antimicrobial photodynamic therapy mediated by methylene blue and potassium iodide to treat urinary tract infection in a female rat model","volume":"8","author":"Huang","year":"2018","journal-title":"Sci. Rep."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"5445","DOI":"10.1128\/AAC.00980-16","article-title":"Broad-spectrum antimicrobial effects of photocatalysis using titanium dioxide nanoparticles are strongly potentiated by addition of potassium iodide","volume":"60","author":"Huang","year":"2016","journal-title":"Antimicrob. Agents Chemother."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1016\/j.jphotobiol.2018.07.027","article-title":"Comparison of two functionalized fullerenes for antimicrobial photodynamic inactivation: Potentiation by potassium iodide and photochemical mechanisms","volume":"186","author":"Huang","year":"2018","journal-title":"J. Photochem. Photobiol. B"},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"468","DOI":"10.1039\/b200977c","article-title":"Photoinactivation of bacterial strains involved in periodontal diseases sensitized by porphycene-polylysine conjugates","volume":"1","author":"Lauro","year":"2002","journal-title":"Photochem. Photobiol. Sci."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"91","DOI":"10.3390\/md8010091","article-title":"Antimicrobial photodynamic therapy: Study of bacterial recovery viability and potential development of resistance after treatment","volume":"8","author":"Tavares","year":"2010","journal-title":"Mar. Drugs"}],"container-title":["Antibiotics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-6382\/8\/4\/211\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:31:57Z","timestamp":1760189517000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-6382\/8\/4\/211"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,11,5]]},"references-count":51,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2019,12]]}},"alternative-id":["antibiotics8040211"],"URL":"https:\/\/doi.org\/10.3390\/antibiotics8040211","relation":{},"ISSN":["2079-6382"],"issn-type":[{"value":"2079-6382","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,11,5]]}}}