Effect of different drying conditions for the viability of Candida albicans present on carriers
Journal Title: Roczniki Państwowego Zakładu Higieny - Year 2014, Vol 65, Issue 1
Abstract
Background. Problems in substantial under recovery of Pseudomonas aeruginosa and Candida albicans from carriers have been demonstrated for laboratories performing phase 2, step 2 efficacy tests on disinfectants relative to levels required by the EN 13697 standard. It was thus necessary to determine recoveries of these microorganisms following procedural losses incurred during drying and to optimise drying conditions such that recoveries then complied with the standard. Objectives. The aim of the study was to establish optimal drying conditions for the recovery of Candida albicans ATCC 10231 from carriers. Material and Methods. The evaluation was performed according to the EN 13697:2001 standard procedure. A test suspension of Candida albicans and interfering substance were inoculated onto the surface of carriers (2 cm diameter stainless steel discs) and then dried under different conditions consisting of: a 37°C incubation with and without an incubator fan as well as at 23°C (room temperature) in a laminar air flow cabinet. Carriers were dried until the surfaces appeared visibly dry and the number of surviving organisms then recovered from the surface were quantified. The following were calculated for colony forming units (cfu); N (log10 cfu in a 0.05 ml test suspension), NC (the control log10 cfu in neutralizing medium), Nts (cfu numbers remaining on the surface) and the N-NC difference which should not exceed 2 log10 when microorganism recoveries are adequate and without any toxicity effects of the neutralising medium. Experiments was conducted using validating procedure (NC) which is performed with distilled water. Results. Drying at 37°C adversely affected the survival of Candida albicans and prevented the levels of microbial recovery from carriers to reach those specified by the EN 13697 standard. However, drying at around room temperatures of 23°C reduced Candida albicans mortality and increased recoveries from the carrier to levels compliant with the standard, where the N-NC differences were not greater than 2 log10. Conclusions. The viability of Candida albicans ATCC 10231 is sufficiently improved when carriers are dried at 23°C, even if the drying time exceeds 60 minutes. The density of the initial test suspension (N) should also be increased.
Authors and Affiliations
E. Röhm-Rodowald, A. Chojecka, B. Jakimiak, O. Wiercińska, K. Kanclerski
Keywords
Related Articles
- EP ID EP246773
- DOI -
- Views 112
- Downloads 0
Microbiological purity assessment of cosmetics used by one and several persons and cosmetics after their expiry date
Background. Microbiological purity of cosmetics provides safety of users during their use, prevents physicochemical changes of a preparation, infections and diseases of the skin. Objective. The aim of this study was to...
Dietetic recommendations after bariatric procedures in the light of new guidelines regarding metabolic and bariatric surgery
The frequency of obesity occurrence is constantly increasing all over the world and becoming global epidemic. Facing the lack of the efficiency of conservative treatment, patients with II and III degree of obesity are q...
Development and validation of a method for determination of selected polybrominated diphenyl ether congeners in household dust
Background. Polybrominated diphenyl ethers (PBDEs) belong to group of so-called persistent organic pollutants (POPs). These compounds occur in nearly all elements of the environment, including household dust which consti...
Compliance of menus with nutritional standards in public and private kindergartens in Croatia
Background. It is necessary to ensure a variety of nutrients in weekly menus in kindergartens according to the recommendations and standards currently in effect. It is also important to follow the energy value of macronu...
Determination of volatile organic compounds in materials from polystyrene intended for contact with food: comparison of HS-GS/MS and SPME-GC/MS techniques
Background. Plastic materials intended for contact with food sometimes exhibit unfavorable organoleptic properties which is related to the presence of volatile organic compounds. These substances not only worsen organole...