Curcumin Antibacterial Effects on Mycoplasma hominis clinical isolates from Vaginosis

Aims: Mycoplasma hominis is involved in the development of non-gonococcal urethritis, bacterial vaginosis, postpartum fever, and rarely bacteremia, peritonitis, arthritis, and meningitis. This study investigated the effect of curcumin against M. hominis species isolated from vaginosis.
Materials & Methods: About 550 samples from female patients with vaginosis were examined. The minimum inhibitory concentration (MIC) ranges of tetracycline, doxycycline, clarithromycin, azithromycin, moxifloxacin, ciprofloxacin, and erythromycin were determined. For this purpose, dilutions ranging from 0.25-4 µg/mL were prepared. In addition, curcumin compound was diluted at 5 and 10 µg/mL concentrations and added to the bacterial suspension in SP-4 broth medium. qRT-PCR was performed to examine the MH16srRNA gene expression upon exposure to 10 µg/mL curcumin.
Findings: Of the 550 samples, 20 were positive for M. hominis. The patients’ age ranged from 23-35 (mean: 26.5±2) years. The MIC ranges of antibiotics included 1->4 µg/mL for doxycycline, 2->4 µg/mL for clarithromycin, 2->4 µg/mL for azithromycin, 2->4 µg/mL for moxifloxacin, 2->4 µg/mL for ciprofloxacin, and 1->4 µg/mL for erythromycin. Exposure to 5 µg/mL curcumin resulted in the inhibition of eight isolates. Curcumin at a 10 µg/mL concentration inhibited the growth of 15 out of 20 isolates after 72 hrs of incubation. The mean expression level of MH16srRNA gene at these concentrations decreased 0.8-1-fold among the isolates compared to the control.
Conclusion: Low levels of M. hominis were detected in vaginal samples in Samawah, Iraq. Curcumin could inhibit the growth of M. hominis causing vaginosis. More in-depth and inclusive studies are required to verify the findings.