Context. Usnea ghattensis G. Awasthi (Usneaceae) endemic fruticose lichen found growing luxuriantly in Northern Western Ghats of India, it also contains Usnic acid as a major chemical and tested against some human pathogenic bacteria. Objective. To explore antimicrobial properties of Usnea ghattensis against some human pathogenic bacteria. Materials and Methods. The lichen was extracted in acetone, methanol, and ethanol. In vitro antimicrobial activity was tested initially by Kirby-Bauer technique of disc diffusion method and was confirmed by minimum inhibitory concentration using Broth microdilution method according to the NCCLS guidelines. Results. Ethanol extract was most effective against Bacillus cereus and Pseudomonas aeruginosa with a zone of inhibition 29.8 ± 0.6？mm and 12.3 ± 0.5？mm diameters at a concentration of 0.2？mg/mL. Acetone and methanol extract demonstrated almost similar activity against Staphylococcus aureus and the zone of inhibition was 24.6 ± 0.5 and 24.7 ± 0.4？mm. Only methanol extract was showing activity against Streptococcus faecalis with a 13.5 ± 0.8？mm zone. MIC value noted against Staphylococcus aureus and Streptococcus faecalis was 6.25？μg/mL and 25？μg/mL, whereas against Bacillus cereus and Pseudomonas aeruginosa, MIC calculated was 3.125？μg/mL and 200？μg/mL, respectively. Conclusion. The present study demonstrates the relatively higher activity of this lichen against not only gram (+) but significantly also against gram (？) bacteria. This indicates that this lichen might be a rich source of effective antimicrobial agents. 1. Introduction Medicinal plants are well-known natural sources for the treatment of various diseases since ancient times. Lichens are among the most fascinating organisms on this planet. Lichen is not a single organism the way most other living things are, but rather it is a combination of two organisms which live together intimately. The fungus forms a thallus or lichenized stroma that may contain characteristic secondary metabolites in all lichens [1]. Lichens are valuable plant resources and are used as medicines, food, fodder, dyes perfume, spice, and for miscellaneous purposes. The lichen flora is rather poor in the vicinity of industrial areas and big cities [2], as lichens are very sensitive to various air pollutions. Thus, these organisms are used as air pollution monitors [3]. The specific, even extreme, conditions of their existence, slow growth, and long duration (maximum lifetime spans to several thousand years) are consistent with their abundance in protective metabolites against different
References
[1]
V. Ahmadijan, The Lichen Symbiosis, John Wiley & Sons, New York, NY, USA, 1993.
[2]
R. Hegnauer, Chemotaxonomy der Pflanzen. Band 1: Thallophyten, Bryophyten, Pteridophyten und Gymnospermen, Birkhaüser, Basel-Stuttgart, 1962.
[3]
A. Jezierski, E. Bylinska, and M. R. D. Seaward, “Electron paramagnetic resonance (EPR) investigations of lichens—1: effects of air pollution,” Atmospheric Environment, vol. 33, no. 28, pp. 4629–4635, 1999.
[4]
G. H. Denton and W. Karlen, “Lichenometry: its application to Holocene moraine studies in Southern Alaska and Swedish Lapland,” Arctic and Alpine Research, vol. 5, pp. 347–372, 1973.
[5]
K. O. Vartia, “The Lichens,” in Antibiotics in Lichens, V. Ahmadjian and M. E. Hale, Eds., pp. 547–561, Academic Press, New York, NY, USA, 1973.
[6]
L. A. Mitscher, S. Drake, S. R. Gollapudi, and S. K. Okwute, “A modern look at folkloric use of anti-infective agents,” Journal of Natural Products, vol. 50, no. 6, pp. 1025–1040, 1987.
[7]
K. Ingolfsdottir, M. A. Hjalmarsdottir, A. Sigurdsson, G. A. Gudjonsdottir, A. Brynjolfsdottir, and O. Steingrimsson, “In vitro susceptibility of Helicobacter pylori to protolichesterinic acid from the lichen Cetraria islandica,” Antimicrobial Agents and Chemotherapy, vol. 41, no. 1, pp. 215–217, 1997.
[8]
K. Hostettman and J. L. Wolfender, “The search for biologically active secondary metabolites,” Pesticide Science, vol. 51, pp. 471–482, 1997.
[9]
I. Karaman, F. Sanin, M. Gulluce, H. Ogütcü, M. Sengul, and A. Adiguzel, “Antimicrobial activity of aqueous and methanol extracts of Juniperus oxycedrusL,” Journal of Ethnopharmacology, vol. 85, pp. 231–235, 2003.
[10]
K. Molnár and E. Farkas, “Current results on biological activities of lichen secondary metabolites: a review,” Zeitschrift fur Naturforschung C, vol. 65, no. 3-4, pp. 157–173, 2010.
[11]
S. Huneck, “The significance of lichens and their metabolites,” Naturwissenschaften, vol. 86, no. 12, pp. 559–570, 1999.
[12]
N. T. Manojlovic, S. Solujic, and S. Sukdolak, “Antimicrobial activity of an extract and anthraquinones from caloplaca schaereri,” Lichenologist, vol. 34, no. 1, pp. 83–85, 2002.
[13]
N. T. Manojlovi？, P. Vasiljevi？, M. Juskovi？, S. Najman, S. Jankovi？, and A. Milenkovi？-Andjelkovi？, “HPLC analysis and cytotoxic potential of extracts from the lichen, Thamnolia vermicularis var. subuliformis,” Journal of Medicinal Plant Research, vol. 4, no. 9, pp. 817–823, 2010.
[14]
N. T. Manojlovic, P. J. Vasiljevic, and Z. S. Markovi？, “Antimicrobial activity of extracts and various fractions of chloroform extract from the lichen Laurera benguelensis,” Journal of Biological Research, vol. 13, pp. 27–34, 2010.
[15]
V. Shukla, G. P. Joshi, and M. S. M. Rawat, “Lichens as a potential natural source of bioactive compounds: a review,” Phytochemistry Reviews, vol. 9, no. 2, pp. 303–314, 2010.
[16]
N. Toma, L. Ghetea, R. Nitu, and D. I. Corol, “Progress and perspectives in the biotechnology of lichens,” Romanian Biotechnological Letters, vol. 6, pp. 1–15, 2001.
[17]
R. W. Bauer, M. D. K. Kirby, J. C. Sherris, and M. Turck, “Antibiotic susceptibility testing by standard single disc diffusion method,” American Journal of Clinical Pathology, vol. 45, pp. 493–496, 1966.
[18]
NCCLS, Methods For Dilution Antimicrobial Susceptibility Tests For Bacteria That Grow Aerobically, Approved Standard, 2nd edn edition, 1992.
[19]
S. C. Sati and S. Joshi, “Antibacterial activity of the Himalayanlichen Parmotrema nilgherrenseextracts,” British Microbiology Research Journal, vol. 1, no. 2, pp. 26–32, 2011.
[20]
O. J. Owolabi, E. K. I. Omogbai, and O. Obasuyi, “Antifungaland antibacterial activities of the ethanolic and aqueous extractof Kigelia africana(Bignoniaceae) stem bark,” African Journal of Biotechnology, vol. 6, no. 14, pp. 1677–1680, 2007.
[21]
NCCLS, PerFormance Standards For Antimicrobial Susceptibility Testing. Twelfth inFormational Supplement, Fort Wayne, Ind, USA, 2002.
[22]
Y. Yang and E. J. Anderson, “Antimicrobial activity of a porcine myeloperoxidase against plant pathogenic bacteria and fungi,” Journal of Applied Microbiology, vol. 86, no. 2, pp. 211–220, 1999.
[23]
P. Hugenholtz, “Exploring prokaryotic diversity in the genomicera,” Genome Biology, vol. 3, no. 2, pp. 1–3, 2002.
[24]
J. Van Heijenoort, “Formation of the glycan chains in thesynthesis of bacterial peptidoglycan,” Glycobiology, vol. 11, no. 3, pp. 25R–36R, 2001.
[25]
M. Gulluce, A. Aslan, M. Sokmen, et al., “Screening the antioxidant and antimicrobial properties of the lichens Parmelia saxatilis, Platismatia glauca, Ramalina pollinaria, Ramalina polymorpha and Umbilicaria nylanderiana,” Phytomedicine, vol. 13, no. 7, pp. 515–521, 2006.
[26]
M. Candan, M. Yilmaz, T. Tay, M. Erdem, and A. O. Turk, “Antimicrobial activity of extracts of the lichen Parmelia sulcata and its salazinic acid constituent,” Zeitschrift Fur Naturforschung C, vol. 62, no. 7-8, pp. 619–621, 2007.
[27]
B. Rankovic, M. Misic, and S. Sukdolak, “Antimicrobial activity of extracts of the lichens Cladonia furcata, Parmelia caperata, Parmelia pertusa, Hypogymnia physodes and Umbilicaria polyphylla,” British Journal of Biomedical Science, vol. 64, no. 4, pp. 143–148, 2007.
[28]
P. R. Burkholder, A. W. Evans, I. McVeigh, and H. K. Thornton, “Antibiotic activity of lichens,” Proceedings of the National Academy of Sciences of the United States of America, vol. 30, pp. 250–255, 1944.
[29]
J. G. Rowe, M. T. Saenz, and M. D. Garcia, “Contribution a a’le tudedel’ activiteantibacterienne de queques lichens du sudde l’Espagne,” Pharmaceutical Francaise, vol. 47, pp. 89–94, 1989.
[30]
D. A. Silva, J. Oliveira, J. E. Maileite, M. Q. Paulo, and L. X. Filho, “Antimicrobial activity of Brazilian lichens,” Biological Society Broteriana, vol. 59, pp. 87–96, 1986.
[31]
I. T. Madamombe and A. J. Afolayan, “Evaluation of antimicrobial activity of extracts from South African Usnea barbata,” Pharmaceutical Biology, vol. 41, no. 3, pp. 199–202, 2003.
[32]
B. C. Behera, N. Verma, A. Sonone, and U. Makhija, “Antioxidantand antibacterial activities of lichen Usnea ghattensis in vitro,” Biotechnology Letters, vol. 27, no. 14, pp. 991–995, 2005.
[33]
A. Karagoz, N. Dogruoz, Z. Zeybek, and A. Aslan, “Antibacterial activity of some lichen extracts,” Journal of Medicinal Plant Research, vol. 3, no. 12, pp. 1034–1039, 2009.
