Xanthorrhizol (XTZ), isolated from Curcuma xanthorrhiza, has potent antifungal and antibacterial activity. It shows very strong activity against Gram-positive bacteria, such as Streptococcus mutans and Staphylococcus aureus, but is generally not active against Gram-negative bacteria. In this study, we explored the possibility of using a combination strategy for expanding the antimicrobial spectrum of XTZ against Gram-negative bacteria. To take advantage of XTZ being a food-grade material, 10 food-grade or generally recognized as safe (GRAS) antimicrobial compounds with low toxicities were selected for combination therapy. In addition, polymyxin B nonapeptide (PMBN), which is less toxic than polymyxin B, was also selected as an outer membrane permeabilizer. The antibacterial activity of various double or triple combinations with or without XTZ were assayed in vitro against four Gram-negative bacterial species (Escherichia coli, Salmonella enterica serovar Typhi, Salmonella enterica serovar Typhimurium, and Vibrio cholerae), with synergistic combinations exhibiting clear activity subjected to further screening. The combinations with the greatest synergism were XTZ + PMBN + nisin, XTZ + PMBN + carvacrol, and XTZ + PMBN + thymol. These combinations also showed potent antimicrobial activity against Shigella spp., Yersinia enterocolitica, and Acinetobacter baumannii. In time-kill assays, the three combinations achieved complete killing of E. coli within 2 h, and S. Typhi and V. cholera within 15 min. This is the first report on expanding the activity spectrum of XTZ against Gram-negative bacteria through combination with PMBN and food-grade or GRAS substances, with the resulting findings being particularly useful for increasing the industrial and medical applications of XTZ.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
Berenbaum, M. 1978. A method for testing for synergy with any number of agents. J. Infect. Dis. 137, J122–J130.
Clinical and Laboratory Standards Institute. 2018. Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically, 11th ed.: M07ed11. CLSI, Wayne, PA, USA.
Cosentino, S., Tuberoso, C.I.G., Pisano, B., Satta, M., Mascia, V., Arzedi, E., and Palmas, F. 1999. In-vitro antimicrobial activity and chemical composition of Sardinian Thymus essential oils. Lett. Appl. Microbiol. 29, 130–135.
de Arauz, L.J., Jozala, A.F., Mazzola, P.G., and Penna, T.C.V. 2009. Nisin biotechnological production and application: A review. Trends Food Sci. Technol. 20, 146–154.
Duwe, A.K., Rupar, C.A., Horsman, G.B., and Vas, S.I. 1986. In vitro cytotoxicity and antibiotic activity of polymyxin B nonapeptide. Antimicrob. Agents Chemother. 30, 340–341.
Hancock, R. and Wong, P. 1984. Compounds which increase the permeability of the Pseudomonas aeruginosa outer membrane. Antimicrob. Agents Chemother. 26, 48–52.
Hwang, J.K., Shim, J.S., Baek, N.I., and Pyun, Y.R. 2000a. Xanthorrhizol: A potential antibacterial agent from Curcuma xanthorrhiza against Streptococcus mutans. Planta Med. 66, 196–197.
Hwang, J., Shim, J., and Pyun, Y. 2000b Antibacterial activity of xanthorrhizol from Curcuma xanthorrhiza against oral pathogens. Fitoterapia 71, 321–323.
Hyldgaard, M., Mygind, T., and Meyer, R.L. 2012. Essential oils in food preservation: Mode of action, synergies, and interactions with food matrix components. Front. Microbiol. 3, 12.
Jeu, L. and Fung, H.B. 2004. Daptomycin: A cyclic lipopeptide antimicrobial agent. Clin. Ther. 26, 1728–1757.
Jorge, P., Pérez-Pérez, M., Rodríguez, G.P., Pereira, M.O., and Lourenço, A. 2017. A network perspective on antimicrobial peptide combination therapies: The potential of colistin, polymyxin B and nisin. Int. J. Antimicrob. Agents 49, 668–676.
Kim, J.E., Kim, H.E., Hwang, J.K., Lee, H.J., Kwon, H.K., and Kim, B.I. 2008. Antibacterial characteristics of Curcuma xanthorrhiza extract on Streptococcus mutans biofilm. J. Microbiol. 46, 228.
Lee, L.Y., Shim, J.S., Rukayadi, Y., and Hwang, J.K. 2008. Antibacterial activity of xanthorrhizol isolated from Curcuma xanthorrhiza Roxb. against foodborne pathogens. J. Food Prot. 71, 1926–1930.
Magi, G., Marini, E., and Facinelli, B. 2015. Antimicrobial activity of essential oils and carvacrol, and synergy of carvacrol and erythromycin, against clinical, erythromycin-resistant Group A Streptococci. Front. Microbiol. 6, 165.
Ofek, I., Cohen, S., Rahmani, R., Kabha, K., Tamarkin, D., Herzig, Y., and Rubinstein, E. 1994. Antibacterial synergism of polymyxin B nonapeptide and hydrophobic antibiotics in experimental Gram-negative infections in mice. Antimicrob. Agents Chemother. 38, 374–377.
Oon, S.F., Nallappan, M., Tee, T.T., Shohaimi, S., Kassim, N.K., Sa’ariwijaya, M.S.F., and Cheah, Y.H. 2015. Xanthorrhizol: A review of its pharmacological activities and anticancer properties. Cancer Cell Int. 15, 100.
Park, Y. and Hahm, K. 2005. Antimicrobial peptides (AMPs): Peptide structure and mode of action. J. Biochem. Mol. Biol. 38, 507–516.
Shin, J.M., Gwak, J.W., Kamarajan, P., Fenno, J.C., Rickard, A.H., and Kapila, Y.L. 2016. Biomedical applications of nisin. J. Appl. Microbiol. 120, 1449–1465.
Shin, B. and Park, W. 2017. Antibiotic resistance of pathogenic Acinetobacter species and emerging combination therapy. J. Microbiol. 55, 837–849.
Vaara, M. 1992. Agents that increase the permeability of the outer membrane. Microbiol. Rev. 56, 395–411.
Wiedemann, I., Benz, R., and Sahl, H.G. 2004. Lipid II-mediated pore formation by the peptide antibiotic nisin: A black lipid membrane study. J. Bacteriol. 186, 3259–3261.
Xu, J., Zhou, F., Ji, B.P., Pei, R.S., and Xu, N. 2008. The antibacterial mechanism of carvacrol and thymol against Escherichia coli. Lett. Appl. Microbiol. 47, 174–179.
Zavascki, A.P., Goldani, L.Z., Li, J., and Nation, R.L. 2007. Polymyxin B for the treatment of multidrug-resistant pathogens: A critical review. J. Antimicrob. Chemother. 60, 1206–1215.
Supplemental material for this article may be found at https://doi.org/www.springerlink.com/content/120956.
Electronic supplementary material
About this article
Cite this article
Kim, M.S., Kim, HR., Kim, H. et al. Expansion of antibacterial spectrum of xanthorrhizol against Gram-negatives in combination with PMBN and food-grade antimicrobials. J Microbiol. 57, 405–412 (2019). https://doi.org/10.1007/s12275-019-8511-2
- synergistic effect