Planta Med 2014; 80 - P2B12
DOI: 10.1055/s-0034-1394889

Antibacterial effect of crude dichloromethane extract and fractions obtained from Vexibia alopecuroides L. Jakovl

T Kustova 1, T Karpenyuk 1, M Jacob 2, C Cantrell 3, S Ross 2
  • 1Al-Farabi Kazakh National University, Faculty of Biology and Biotechnology, Almaty, Kazakhstan
  • 2School of Pharmacy, NCNPR, The University of Mississippi, University, USA
  • 3Natural Products Utilization Research Unit, USDA-ARS, University, USA

Diabetic foot infection (DFI) is one of the most frequent and complex problems among patients suffering from diabetes. DFI is polymicrobial in nature. Moreover most of the bacteria have multidrug resistance. Therefore, much attention has been paid to find biological active substances from plants that help to solve this problem. This study was designed to evaluate the antibacterial activity of the crude dichloromethane extract and fractions obtained from Vexibia alopecuroides L.. The roots of V. alopecuroides were extracted by sequential soaking with dichloromethane (DCM) and ethanol. The DCM crude extract showed good antibacterial activity. Therefore, the DCM crude extract was subjected to bioassay-guided fractionation. Column eluate was collected on the basis of TLC similarities and recombined into 10 fractions. Antimicrobial activity of crude extract from V. alopecuroides and extract fractions were evaluated using NCCLS modified version of broth micro-dilution assays [1, 2]. The antibacterial activity of the samples was more effective inhibiting the growth of Gram-positive bacteria than Gram-negative bacteria. Three fractions (D, E, H) showed the highest antibacterial activity against both methicillin-resistant Staphylococcus aureus and S. aureus with IC50 value < 0.8 µg/ml compared to the IC50 values of 0.1 µg/ml of standard drug ciprofloxacin. The present study demonstrated promising results against S. aureus and methicillin-resistant S. aureus, which represents an important step in searching and developing a new antibacterial agent against diabetic foot infections.

Keywords: Vexibia alopecuroides L., crude extract, fractions, antibacterial activity

References:

[1] NCCLS. Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria that Grow Aerobically M7-A5. National Committee on Clinical Laboratory Standards. 2000; 20(2).

[2] NCCLS. Reference Method for Broth Dilution Antifungal Susceptibility Testing of Conidium-Forming Filamentous Fungi; Proposed Standard, M38-P. National Committee on Clinical Laboratory Standards. 1998; 18(13).