Antimicrobial activities of gynura procumbens leaves extract against selected bacteria / Liliwirianis Nawi ...[et al.]

Gynura procumbens or Sambung Nyawa is a tropical plants species from the Asteraceae family.
The objectives of this study were to determine antimicrobial activity and Minimal Inhibition
Concentration (MIC) of G. procumbens leaf extracts against selective Gram-positive and Gramnegative bacteria. Methanol and hexane were the two extraction solvents that had been used. Four
concentrations of extracts; 50 mg/mL, 100 mg/mL, 200 mg/mL, and 400 mg/mL were prepared
for antimicrobial activity. Meanwhile for MIC determination, 6.25 mg/mL, 12.5 mg/mL, 25
mg/mL and 50 mg/mL concentrations were prepared. By using disc diffusion method, the
methanol extract of G. procumbens leaves showed antimicrobial activities against Staphylococcus
aureus, Bacillus subtilis, Klebsiella pneumoniae, and Pseudomonas aeruginosa compared to
hexane extract. Highest antimicrobial activities were recorded against S. aureus at 400 mg/mL
concentrations with 10.5 mm of inhibition zone. Broth dilution assay resulted MIC for methanol
crude extract against S. aureus, B. subtilis, K. pneumoniae, and P. aeruginosa were at 12.5 mg/mL,
25 mg/mL, and 50 mg/mL, respectively