Fig. 2.

Cleansing effect of L-arginine on the salivary biofilm formed on plastic discs. a Crystal violet staining of the biofilm retaining on the discs after washing. The biofilm formed on the plastic disc was washed for 30 min with 10 mM citrate buffer (pH3.5; Cit), 0.5 M each of L-arginine (Arg), L-glycine (Gly), L-lysine (Lys) or L-alanine (Ala), which were adjusted the pH to 3.5 with 10 mM citrate buffer. b Quantification of the salivary biofilm retaining on the discs. The crystal violet was eluted from the discs shown in panel A with acetic acid and their absorbance at 550 nm was measured. Relative values to citrate sample are shown