Objectives: To investigate the effectiveness of polyaminopropylbiguanide (ProntoLind), sodium chlorite (TheraBreath), povidone iodine (Betadine), Hamamelis virginiana extract (Systema), octenidine hydrochloride (Octenidol), chlorhexidine digluconate (Corsodyl), and essential oil mouthrinses (Listerine) against C. glabrata planktonic cells and biofilms. Methods: Standardized inocula of C. glabrata ATCC 90030 were prepared and minimum inhibitory concentrations (MICs) of the mouthrinses were determined in accordance with Clinical and Laboratory Standards Institute (CLSI) Guidelines for the broth microdilution assay. Minimum fungicidal concentrations (MFCs) were determined by culturing optically clear wells. Mouthrinse efficacy against pre-formed biofilms was evaluated after one minute, and after five minutes of exposure.
Results: Octenidine hydrochloride and polyaminopropylbiguanide exhibited the highest MICs (1:2048 dilution), while the latter agent and chlorhexidine demonstrated fungicidal activity at 1:512 dilution. The essential oil exhibited significantly greater anti-biofilm activity (p≤0.002) than the other mouthrinses at an exposure time of one minute, with a 52% reduction in viable counts. Chlorhexidine reduced viable counts by 37%, and was significantly more effective than polyaminopropylbiguanide (p=0.001), sodium chlorite (p>0.001), povidone iodine (p=0.001), Hamamelis virginiana extract (p<0.001), and octenidine hydrochloride (p<0.001). A 13% reduction was observed with Hamamelis virginiana extract, while no measurable reductions were evident with povidone iodine, polyaminopropylbiguanide, sodium chlorite, or octenidine hydrochloride. Anti-biofilm activity of the essential oil remained significantly greater (98%; p<0.001) than the other mouthrinses at a five minute exposure time. Viable count reductions with chlorhexidine (80%) were significantly greater than povidone iodine (73%; p=0.001), polyaminopropylbiguanide (68%; p=0.001), and octenidine hydrochloride (71%; p=0.022). Conclusions: The essential oil mouthrinse exhibited the greatest anti-biofilm activity at both one and five minute exposure times. The standard rinsing time of one minute recommended by most commercial mouthrinse manufacturers may be insufficient for the reduction of C. glabrata.
South East Asian Division Meeting
2015 South East Asian Division Meeting (Bali, Indonesia) Bali, Indonesia
2015 081 Microbiology / Immunology
Ng, Sam
( University of Hong Kong
, Hong Kong
, Hong Kong
)
Lai, Dominic
( University of Hong Kong
, Hong Kong
, Hong Kong
)
Cheung, Becky
( University of Hong Kong
, Hong Kong
, Hong Kong
)
Mcgrath, Colman
( University of Hong Kong
, Hong Kong
, Hong Kong
)
Tsang, Paul
( Technological and Higher Education Institute of Hong Kong
, Hong Kong
, Hong Kong
)
Lam, Otto
( University of Hong Kong
, Hong Kong
, Hong Kong
)