{"title":"Synergistic antifungal effect of naturally-derived antimicrobials with penetration enhancer against Candida albicans biofilm at 5 °C and 22 °C","authors":"Byung Soo Ko, Seon Gyeong Park, Min Suk Rhee","doi":"10.1016/j.jiph.2025.102882","DOIUrl":null,"url":null,"abstract":"<div><h3>Background</h3><div>Biofilms of fungi such as <em>Candida albicans</em> (<em>C. albicans</em>) can survive even at cold temperatures and are generally difficult to eradicate with well-known antimicrobials. The aim of this study was to develop a novel synergistic technique against <em>C. albicans</em> biofilms using low concentrations of propylene glycol (PG), as a penetration enhancer. It helps naturally-derived antimicrobials [caprylic acid (CA) and carvacrol (CAR)] permeate <em>C. albicans</em> biofilms and cell membranes within short times even in cold environments.</div></div><div><h3>Methods</h3><div><em>C. albicans</em> biofilms formed on stainless steel coupons were treated with antifungal complexes (PG, CA and CAR at 0.6–1.2 mM) for 1 or 5 min at 5 and 22°C. PG was selected as the highest fungicidal efficacy, as well as its odourless, colourless nature and excellent solubility compared to other penetration enhancers (isopropyl citrate, laurocapram). To visualize cell damage by antifungal complex, treated biofilms at 5°C and 22°C were examined using the confocal microscopy and field emission scanning electron microscopy.</div></div><div><h3>Results</h3><div>Each substance (PG, CA, CAR), when applied alone to <em>C. albicans</em> biofilms for 5 min, showed less than 0.50 log reduction at both 5 and 22°C. <em>C. albicans</em> biofilm was completely eradicated by PG + CA + CAR (all 1.2 mM) after 5 min at 5 and 22°C (> 6.20 log reduction), but treatment mixtures without PG were incompletely eliminated after 1 min at 5°C (1.75 log reduction) and 22°C (3.75 log reduction). Based on the visualization of biofilms, PG + CA + CAR (all 1.2 mM) resulted in remarkable membrane disruption and cell detachment from stainless steel coupons in contrast to the other treatment conditions.</div></div><div><h3>Conclusion</h3><div>This study indicates that trace amounts of developed antifungal complex could be an effective way to inactivate fungal biofilms on the surfaces of the medical and healthcare field even at cold temperatures.</div></div>","PeriodicalId":16087,"journal":{"name":"Journal of Infection and Public Health","volume":"18 10","pages":"Article 102882"},"PeriodicalIF":4.7000,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Infection and Public Health","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S187603412500231X","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"INFECTIOUS DISEASES","Score":null,"Total":0}
引用次数: 0
Abstract
Background
Biofilms of fungi such as Candida albicans (C. albicans) can survive even at cold temperatures and are generally difficult to eradicate with well-known antimicrobials. The aim of this study was to develop a novel synergistic technique against C. albicans biofilms using low concentrations of propylene glycol (PG), as a penetration enhancer. It helps naturally-derived antimicrobials [caprylic acid (CA) and carvacrol (CAR)] permeate C. albicans biofilms and cell membranes within short times even in cold environments.
Methods
C. albicans biofilms formed on stainless steel coupons were treated with antifungal complexes (PG, CA and CAR at 0.6–1.2 mM) for 1 or 5 min at 5 and 22°C. PG was selected as the highest fungicidal efficacy, as well as its odourless, colourless nature and excellent solubility compared to other penetration enhancers (isopropyl citrate, laurocapram). To visualize cell damage by antifungal complex, treated biofilms at 5°C and 22°C were examined using the confocal microscopy and field emission scanning electron microscopy.
Results
Each substance (PG, CA, CAR), when applied alone to C. albicans biofilms for 5 min, showed less than 0.50 log reduction at both 5 and 22°C. C. albicans biofilm was completely eradicated by PG + CA + CAR (all 1.2 mM) after 5 min at 5 and 22°C (> 6.20 log reduction), but treatment mixtures without PG were incompletely eliminated after 1 min at 5°C (1.75 log reduction) and 22°C (3.75 log reduction). Based on the visualization of biofilms, PG + CA + CAR (all 1.2 mM) resulted in remarkable membrane disruption and cell detachment from stainless steel coupons in contrast to the other treatment conditions.
Conclusion
This study indicates that trace amounts of developed antifungal complex could be an effective way to inactivate fungal biofilms on the surfaces of the medical and healthcare field even at cold temperatures.
期刊介绍:
The Journal of Infection and Public Health, first official journal of the Saudi Arabian Ministry of National Guard Health Affairs, King Saud Bin Abdulaziz University for Health Sciences and the Saudi Association for Public Health, aims to be the foremost scientific, peer-reviewed journal encompassing infection prevention and control, microbiology, infectious diseases, public health and the application of healthcare epidemiology to the evaluation of health outcomes. The point of view of the journal is that infection and public health are closely intertwined and that advances in one area will have positive consequences on the other.
The journal will be useful to all health professionals who are partners in the management of patients with communicable diseases, keeping them up to date. The journal is proud to have an international and diverse editorial board that will assist and facilitate the publication of articles that reflect a global view on infection control and public health, as well as emphasizing our focus on supporting the needs of public health practitioners.
It is our aim to improve healthcare by reducing risk of infection and related adverse outcomes by critical review, selection, and dissemination of new and relevant information in the field of infection control, public health and infectious diseases in all healthcare settings and the community.