Nutrition. 2016 Apr;32(4):486-90. doi: 10.1016/j.nut.2015.10.010. Epub 2015 Oct 30.

Kaffir lime leaves extract inhibits biofilm formation by Streptococcus mutans.

Kooltheat N1, Kamuthachad L1, Anthapanya M1, Samakchan N1, Sranujit RP2, Potup P1, Ferrante A3, Usuwanthim K4.

• 1Cellular and Molecular Immunology Research Unit, Faculty of Allied Health Sciences, Naresuan University, Phitsanulok, Thailand.
• 2Cellular and Molecular Immunology Research Unit, Faculty of Allied Health Sciences, Naresuan University, Phitsanulok, Thailand; Thai Traditional Medicine College, Rajamangala University of Technology Thanyaburi, Pathum Thani, Thailand.
• 3Department of Immunopathology, SA Pathology at Women's and Children's Hospital, Robinson Research Institute, University of Adelaide, South Australia.
• 4Cellular and Molecular Immunology Research Unit, Faculty of Allied Health Sciences, Naresuan University, Phitsanulok, Thailand. Electronic address: ajkarn_9@hotmail.com.

Abstract

OBJECTIVES:

Although kaffir lime has been reported to exhibit antioxidant and antileukemic activity, little is known about the antimicrobial effect of kaffir lime extract. Because Streptococcus mutans has been known to cause biofilm formation, it has been considered the most important causative pathogen of dental caries. Thus, the effective control of its effects on the oral biofilm is the key to the prevention of dental caries. The aims of the present study were to investigate the effect of kaffir lime leaves extract on biofilm formation and its antibacterial activity on S. mutans.

METHODS:

We examined the effect of kaffir lime leaves extract on growth and biofilm formation of S. mutans. For the investigation we used a kaffir lime extract with high phenolic content. The minimum inhibitory concentration of the extract was determined by broth microdilution assay. The inhibitory effect of the test substances on biofilm formation was also investigated by biofilm formation assay and qRT-PCR of biofilm formation-associated genes.

RESULTS:

Kaffir lime leaves extract inhibits the growth of S. mutans, corresponding to the activity of an antibiotic, ampicillin. Formation of biofilm by S. mutans was also inhibited by the extract. These results were confirmed by the down-regulation of genes associated with the biofilm formation.

CONCLUSIONS:

The findings highlight the ability of kaffir lime leaves extract to inhibit S. mutans activity, which may be beneficial in the prevention of biofilm formation on dental surface, reducing dental plaque and decreasing the chance of dental carries.

Copyright © 2016 Elsevier Inc. All rights reserved.

KEYWORDS:

Biofilm formation; Kaffir lime; Minimum inhibitory concentration; Streptococcus mutans

PMID:

26743975