Abstract
Crude ethanol extracts from dried Phyllanthus niruri (DPN), fresh (FPB) and dried Piper betle Linn. (DPB) were tested for their inhibitory activity against three foodborne pathogenic microorganisms (Escherichia coli, Staphylococcus aureus and Salmonella derby) and five foodborne spoilage microorganisms (Pseudomonas aeruginosa, Bacillus subtilis, Lactobacillus sp., Saccharomyces cerevisiae and Aspergillus niger). Screening for antimicrobial activity using disc diffusion assay showed the inhibition of all tested microorganisms by DPB. On the other hand, only two of the test microorganisms (S. aureus and Lactobacillus sp.) were inhibited by FPB. Likewise, Lactobacillus sp. was the only test microorganism inhibited by DPN. Minimum inhibitory concentrations (MIC’s) of the extracts were determined using agar dilution method on the same test microorganisms. Extract from DPB gave MIC values ranging from 160 to 10,240 parts per million (ppm). Results showed S. cerevisiae as the most sensitive and B. subtilis as the least sensitive to the extract. Both FPB and DPN extracts did not show growth inhibition of test microorganisms at the highest concentration used (10,240 ppm)