This study aimed to investigate the inhibitory effect of probiotic microorganisms against Streptococcus pyogenes. A total of 85 pharyngeal swaps were collected from children infected with pharyngitis. Four isolates S. pyogenes were obtained and then evaluated for the activity of its spreading factors for infection streptokinase and hyaluronidase. As a probiotic microorganism, Lactobacillus acidophilius after propagating in MRS medium, results revealed that’s both unconcentrated and concentrated filtrate possessed inhibitory activity against three (S16, S20 and S28) of the four isolates of S. pyogenes, while the fourth isolate S30 had no such effect. When Streptococcus salivarius was also used as a probiotic, it was able to exerts inhibitory activity against all four isolates of Streptococcus pyogenes by using the deferred antagonism test Adversely, concentrated filtrate of the probiotic yeast, Saccharomyces boulardii, had no inhibitory effect against any of the four isolates of pathogenic S. pyogenes used in the study. All Streptococcus pyogenes isolates were resistant to erythromycin, azithromycin, chloramphenicol, clindamycin, but sensitive to amoxicillin, tetracycline, and vancomycin, and have variant result with penicillin.When activity of the two enzymes (streptokinase and hyaluronidase ) produced by S. pyogenes was tested, results showed that all its four isolates possessed the ability to produce reptokinase by using both the casinolytic assay and radial caseinolysis assay.Regarding hyaluronidase, results showed that only three of the S.pyogenes isolates (S16, S20 and S28) were able to produce the enzyme
when detected by the two methods; plate assay and turbidity reduction assay, while isolate S30 was unable to do so by any of the two methods used. After subjection of the two crude enzymes reptokinase and hyaluronidase) to the treatment with each of the; crude extraction of bacteriocin from S. salivarius, concentrated filtrates of Lb. acidophilus, concentrated filtrates of S. boulardii and of the six antibiotics(erythromycin, azithromycin, chloramphenicol, clindamycin, amoxicillin, tetracycline, and vancomycin) results obtained could be summarized as follows:
Streptokinase activity was completely inhibited by the bacteriocin while it was partially inhibited by S. boulardii.
Streptokinase activity was not affected by the filtrate of Lb.
acidophilus.
Only amoxillin, tetracycline and chloramphenicol from those
antibiotics used in this study caused partial inhibition in the activity
of streptokinase.
Hyaluronidase activity was completely inhibited by the bacteriocin
that produced by S. salivarius.
Partial inhibition of hyaluronidase was occurred by treating with
each of the of S. boulardii and Lb. acidophilus filtrates.
Any of the six antibiotics used in this study had no effect on the
hyaluronidase activity.
