Abstract:
Research has been done to determine the potential of bacteriocins in yogurt that found
on the market by tested against Shigella dysenteriae and Salmonella thypi. This study was
held in January and March 2013 with test samples of yogurt and yogurt supernatant against
test bacteria. The test method was using the well diffusion test on MHA. Bacteria grown in
media every 24 hours, perforated with tubes durham as well in order. Each of the wells fill
with yogurt and yogurt supernatant. Medium incubated on 37
0
C for 24 hours, the
antibacterial activity was measured by inhibition zone diameter formed. The results showed
the yogurt sample test, that the bacteriocins produced by lactic acid bacteria on commercial
yogurt can not inhibit Shigella dysenteriae and Salmonella thypi. In supernatant yogurt the
test, bacteriocin production by lactic acid bacteria from yogurt commercial that has been
centrifuged unable to inhibit Shigella dysenteriae and Salmonella thypi. The growing of lactic
acid bacteria was disturb and makes the bacteriocins results on the sample and supernatan can
not inhibit the bacterial test. Antibacterial potency of the yogurt sample and the supernatant
can not be determined because no inhibition zone formed.
