To evaluate the antimicrobial and antibiofilm activity of A. lakoocha
extract against oral pathogens by an in vitro method.
The dried powder of the aqueous extract of A. lakoocha
was purchased from a Thai traditional drug store. Representative strains of oral pathogens ( Streptococcus mutans
ATCC 25175, Streptococcus sobrinus
ATCC 33478, Enterococcus faecalis
ATCC 19433, Lactobacillus fermentum
ATCC 14931, Lactobacillus salivarius
ATCC 11741, Aggregatibacter actinomycetemcomitans
ATCC 33384, Porphyromonas gingivalis
ATCC 33277, Prevotella intermedia
ATCC 25611, Prevotella nigrescens
ATCC 25261, Fusobacterium nucleatum
ATCC 25586 and Tanerella forsythia
ATCC 43037) were tested for minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) using a microdilution technique, as well as by a time kill assay. Antibiofilm activity was investigated by a 3-[4, 5-dimethyl-2-thiazolyl]-2, 5-diphenyl-2H-tetrazolium-bromide (MTT) assay.
All tested strains were susceptible to A. lakoocha
extract with variable degrees of antimicrobial inhibition. The extract was effective against both Gram-negative bacteria (Aggregatibacter actinomycetemcomitans
, Porphyromonas gingivalis
) and Gram-positive bacteria (Streptococcus mutans
, Streptococcus sobrinus
), with MIC ranging from 0.10 – 0.39 mg/ml and MBC from 0.10 – 3.12 mg/ml. Killing activity depended on time and concentrations of the extract. The extract acted as a potent antibiofilm agent with dual actions, preventing biofilm formation and also eradicating the existing biofilm. Conclusion: A. lakoocha
extract possesses compounds with good antimicrobial properties that may be used for oral infectious diseases caused by certain oral pathogens associated with dental caries and/or periodontal diseases. For the application, A. lakoocha
extract may be incorporated in mouthwash or toothpaste.