Abstract:
Infection from pathogenic bacteria can cause various diseases in humans, such
as diarrhea. The diarrheal disease can be caused by bacteria Escherichia coli,
Salmonella typhimurium, and Shigella flexineri. Meanwhile, actinomycetes are reported
to be one of the producers of antibiotics. The actinomycetes used were isolated from
soil in the Universitas Riau Arboretum, namely isolates B1.06, B3.13, C2.18, A2.01,
and C2.20. The purpose of this study was to study the antibacterial activity of secondary
metabolites of Actinomycetes extracted using ethyl acetate against pathogenic bacteria
that cause diarrheal diseases. The disk diffusion method was used for testing
antibacterial activity. From the results, it was found that the actinomycetes isolate was
able to overcome the pathogenic bacteria, with a diameter of inhibition zone formed was
8.2 mm against Salmonella typhimurium and 20.6 mm against Shigella flexineri. The
diameter of the inhibition zone formed was compared with the tetracylcline and
produced antibacterial activity criteria of actinomycetes isolates that were resistant,
intermediate and sensitive.
