Synergistic Effect between Baicalein and Antibiotics against Clinic Methicillin and Vancomycin-Resistant Staphylococcus aureusYoung-Soo Lee1, Eun-Kyung Jung2 and Jeong-Dan Cha3*
- *Corresponding Author:
- Jeong-Dan Cha
Department of Natural Product Research
Institute of Jinan red ginseng
520-9 Banwol-ri, Jinan-eup
567-801 South Korea
Tel : +82-63-432-0913
Fax : +82-63-432-0910
E-mail: [email protected]
Received Date: December 6, 2014; Accepted Date: January 12, 2015; Published Date: January 25, 2015
Citation: Young-Soo Lee,Eun-Kyung Jung and Jeong-Dan Cha (2015) Synergistic Effect between Baicalein and Antibiotics against Clinic Methicillin and Vancomycin-Resistant Staphylococcus aureus. Chemotherapy 3:141. doi:10.4172/2167-7700.1000141
Copyright: © 2014 Jeong-Dan Cha. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Baicalein is one of the major flavonoids in Scutellaria baicalensis Georgi, which has long been used in several biological effects, such as antiviral, anti-inflammation, anti-hepatotoxicity, and anti-tumor properties, have been reported. In this study, baicalein demonstrated strong antibacterial activity against clinic isolated methicillin and vancomycin-resistant Staphylococcus aureus (MRSA and VRSA) in this experiment. Baicalein was determined against clinic isolated MRSA 1-16 with MIC and MBC values ranging from 64 to 256 and 64 to 512 μg/ml; for MSSA 1-2 from 128 and 256 μg/ml and 128 and 512 μg/ml; for VRSA 1-2 from 64 and 128 μg/ml and 64 and 512 μg/ml, respectively. The range of MIC50 and MIC90 of baicalein were 16-64 μg/ml and 64-256 μg/ml, respectively. The combination effects of baicalein with antibiotics were synergistic (FIC index <0.5) against most of tested clinic isolated MRSA, MSSA, and VRSA except additive, MRSA 7 in oxacillin and MRSA 8 and 15 in vancomycin (FIC index <0.625-0.75). Furthermore, a time-kill study showed that the growth of the tested bacteria was completely attenuated after 2-6 h of treatment with the ½ MIC of baicalein, regardless of whether it was administered alone or with ampicillin, oxacillin, or vacomycin. The results suggest that baicalein could be employed as a natural antibacterial agent against multidrug-resistant pathogens infection.