Background: Antimicrobial combination is one of the promising treatment to combat bacterial pathogens, especially multidrug resistant bacteria, including methicillin resistant Staphylococcus aureus. Plant extracts haue been used to assess its minimum inhibitory concentration against S. aureus. However, study on combination of plant extract and comercially available antibiotics, such as oxacillin is still rare. So, we tried to combine selected plant extract with oxacillin to observe their efficacy against S.aureus.
Methods: We used plant extract from 22 spices and fruits, such as nutmeg, coriander,
mangosteen, black pepper, god's crown, clove, cinnamon, star anise, black cumin, bilimbi, centella, red ginger, bitter ginger, Java turmeric, turmeric, finger root, white turmeric, galangal, greater galangal, butterfly pea, shallot, garlic. Stophylocoecus aureus strain that used in this research was S.aureus KCTC 1621 (methicillin sensitive 5. aureus), and four strain methicillin resistant S.aureus (CCARM 3090, CCARM 3091, CCARM 309S, CCARM 3102). Microdilution broth assay was used to determine MIC of the plant extract, while checkerboard assay was used to assay combination treatment between oxacillin and plant extract.
Results: MIC determination of the plant extracts showed that mangosteen rind extract
MIC against methicillin resistant S.aureus(MIC4-8 mikrog/mL) was not different from methicillin sensitive S.aureus (MIC 4 mikrog/mL). Unfortunately, combination between oxacillin and mangosteen rind extract did not demonstrate synergistic effect (FICI >0.S). Synergistic effect (F1CJ <0.S) was demonstrated by combination betweeen oxacillin and extract of Java turmeric, finger root's rhizome, nutmeg, or '
cinnamon bark.
Conclusion: These results exhibited the potency of plant extract to be used in combination with oxacillin to combat methicillin resistant S.aureus. |