• Vinothkannan Ravichandiran Quorum sensing Laboratory, Centre for Research on Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA University, Thanjavur, Tamil Nadu, India
  • Hema M Quorum sensing Laboratory, Centre for Research on Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA University, Thanjavur, Tamil Nadu, India
  • Adline Princy S Quorum sensing Laboratory, Centre for Research on Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA University, Thanjavur, Tamil Nadu, India


Objective: To investigate the potentiality of Meliadubiastem extracts for quorum sensing (SdiA-selective) inhibitory activity against uropathogenic Escherichia coli (UPEC).

Methods: The antimicrobial (cell-density) and anti-virulent (swarming motility, protein, protease, hemolysis, hemagglutination, hydrophobicity and biofilm inhibition) properties of the Meliadubia stem extracts were performed.

Results: The biofilm, hemolysis, swarming motility were inhibited by 45.71%, 12.97 % and 33.33% respectively when the media were supplemented with 30 mg/ml of ethanolic extract. The GC-MS spectrum of ethanolic extract showed an array of 49 structurally unrelated compounds with the natural ligand, AHL. Their interaction with the quorum regulator, SdiA, was predicted by Glide module of Schrödinger suite and the ligands C 7, C 20, C 28 showed appreciable activity with the following G-Score 11.4, 10.7, 9.9 respectively. In vitro and in silico molecular docking analysis data showed fairly good correlation, suggesting that the ethanolic extract has the potential to attenuate the quorum sensing of UPEC. Further investigation is desired to study the antagonistic effect of the above ligand by in vitro and in vivo strategies.

Conclusion: The quorum quenching activity of Meliadubia stem was proven from the overall analysis and its effect towards the inhibition of biofilm and virulence factors were analyzed.


Keywords: Quorum sensing, Quorum quenching, Meliadubia, Uropathogenic E. coli, SdiA


Download data is not yet available.


1. Nicolle LE. Uncomplicated urinary tract infection in adults including uncomplicated pyelonephritis. Urol Clin North Am 2008;35:1-12.
2. Hirakawa H, Inazumi Y, Masaki T, Hirata T, Yamaguchi A. Indole induces the expression of multidrug exporter genes in Escherichia coli. Mol Microbiol 2005;55:1113-26.
3. Anyanful A. Paralysis and killing of Caenorhabditis elegans by enteropathogenic Escherichia coli requires the bacterial tryptophanase gene. Mol Microbiol 2005;57:988-1007.
4. Lee J. Indole cell signaling occurs primarily at low temperatures in Escherichia coli. ISME J 2008;2:1007-23.
5. Yao Y, Martinez-Yamoat, MA, Dyson HJ. Backbone and side chain H1, C13 and N15 assignments of Escherichia coli SdiA1-171, the autoinducer binding domains of a Quorum sensing protein NMR. J Biomol Struct Dyn 2005;31:373-4.
6. Wei Y, Vollmer AC, LaRossa RA. In vivo titration of mitomycin C action by four Escherichia coli genomic regions on multicopy plasmids. J Bacteriol 2001;183:2259-64.
7. Lee J, Maeda T, Hong SH, Wood TK. Reconfiguring the quorum-sensing regulator SdiA of Escherichia coli to control biofilm formation via indole and N-acylhomoserine lactones. Appl Environ Microbiol 2009;75:1703-16.
8. Hema M, Balasubramanian S, Princy SA. Meddling vibrio cholerae murmurs: a neoteric advancement in cholera research. Indian J Microbiol 2015;55:121-30.
9. Adline Princy S, Vinothkannan Ravichandiran, Surasikha Rangarajan. E. coli quorum sensing: appraisal towards curtailing pathogenesis. Biotechnol Indian J 2014;9:41-7.
10. Susheela T, Balaravi P, Theophilus J, Narender Reddy T, Reddy P. Evaluation of hypoglycaemic and antidiabetic effect of Melia dubia CAV fruits in mice. Curr Sci 2008;94:1191-5.
11. Vinothkannan Ravichandiran SK, Shrimathi R, Princy SA. Virtual screening of SdiA Inhibitors from melia dubia to curtail uropathogenic E. coli Quorum Sensing. Asian J Chem 2013;25:95-100.
12. Malarvannan S, Giridharan R, Sekar S, Prabavathy V, Nair S. Ovicidal activity of crude extracts of few traditional plants against Helicoverpa armigera (Hubner)(Noctuidae: Lepidoptera). J Biopestic 2009;2:64-71.
13. Gupta V, Saggu S, Tulsawani R, Sawhney R, Kumar R. A dose dependent adaptogenic and safety evaluation of Rhodiola imbricata Edgew, a high altitude rhizome. Food Chem Toxicol 2008;46:1645-52.
14. Carlberg D. Determining the effects of antibiotics on bacterial growth by optical and electrical methods. Antibiotics Laboratory Med 1986;64-92.
15. Lee J, Bansal T, Jayaraman A, Bentley WE, Wood TK. Enterohemorrhagic Escherichia coli biofilms are inhibited by 7-hydroxyindole and stimulated by isatin. Appl Environ Microbiol 2007;73:4100-9.
16. Lowry OH, Rosebrough NJ, Farr AL, Randall RJ. Protein measurement with the Folin phenol reagent. J Biol Chem 1951;193:265-75.
17. Kunitz M. Isolation of a crystalline protein compound of trypsin and of soybean trypsin-inhibitor. J Gen Physiol 1947;30:311-20.
18. Van Den Bosch JF, Postma P, De Graaff J, MacLaren DM. Determination of the α-haemolytic activity of haemolytic urinary Escherichia coli strains. FEMS Microbiol Lett 1980;8:75-7.
19. Evans DG, Evans DJ, Tjoa W. Hemagglutination of human group A erythrocytes by enterotoxigenic Escherichia coli isolated from adults with diarrhea: correlation with colonization factor. Infect Immun 1977;18:330-7.
20. Chapman JS, Georgopapadakou NH. Routes of quinolone permeation in Escherichia coli. Antimicrob Agents Chemother 1988;32:438-42.
21. Vandeputte OM. Identification of catechin as one of the flavonoids from Combretum albiflorum bark extract that reduces the production of quorum-sensing-controlled virulence factors in Pseudomonas aeruginosa PAO1. Appl Environ Microbiol 2010;76:243-53.
22. Hema M, Karthi S, Adline Princy S. Design of LuxO based inhibitors to reverse engineer the genetic circuit of Vibrio cholera-an anti-virulent cholera therapy. J Chem Pharm Res 2015;7:1544-52.
23. Chakraborty SP, Sahu SK, Pramanik P, Roy S. Biocompatibility of folate–modified chitosan nanoparticles. Asian Pac J Trop Biomed 2012;2:215-9.
24. Hentzer M. Inhibition of quorum sensing in Pseudomonas aeruginosa biofilm bacteria by a halogenated furanone compound. Microbiol 2002;148:87-102.
25. JH Z. Biostatistical analysis, fourth ed. Prentice Hall International, Inc. Press; 1988.
26. Ren D, Sims J, Wood T. Inhibition of biofilm formation and swarming of Bacillus subtilis by (5Z)‐4‐bromo‐5‐(bromomethylene)‐3‐butyl‐2 (5H)‐furanone. Lett Appl Microbiol 2002;34:293-9.
27. You J. Inhibition of vibrio biofilm formation by a marine actinomycete strain A66. Appl Microbiol Biotechnol 2007;76:1137-44.
28. Kunze B. Damage of Streptococcus mutans biofilms by carolacton, a secondary metabolite from the myxobacterium Sorangium cellulosum. BMC Microbiol 2010;10:199.
29. Balagué CE, De Ruiz CS, Rey R, De Duffard AMaE, Nader-Macı́as MaE. Effect of the herbicide 2, 4-dichlorophenoxyacetic acid on uropathogenic Escherichia coli virulence factors. Toxicology 2002;177:143-55.
30. Boyer RR. Influence of curli expression by Escherichia coli O157:H7 on the cell's overall hydrophobicity, charge, and ability to attach to lettuce. J Food Protection® 2007;70:1339-45.
31. Evans D, Allison D, Brown M, Gilbert P. Susceptibility of Pseudomonas aeruginosa and Escherichia coli biofilms towards ciprofloxacin: effect of specific growth rate. J Antimicrob Chemother 1991;27:177-84.
32. Bakri I, Douglas C. Inhibitory effect of garlic extract on oral bacteria. Arch Oral Biol 2005;50:645-51.
33. Wang W-B. Inhibition of swarming and virulence factor expression in proteus mirabilis by resveratrol. J Med Microbiol 2006;55:1313-21.
34. Inoue T, Shingaki R, Fukui K. Inhibition of swarming motility of Pseudomonas aeruginosa by branched-chain fatty acids. FEMS Microbiol Lett 2008;281:81-6.
35. Stepanović S, Ćirković I, Ranin L. Biofilm formation by salmonella spp. and listeria monocytogenes on plastic surface. Lett Appl Microbiol 2004;38:428-32.
36. Adline Princy S, Vinod kannan R, Navya Rajesh D, Priyadarshini D, Praveen Krishna V. Myristic acid methyl ester: a potential quorum quencher from Melia dubia against uropathogenic E. coli. Biotechnology. Indian J 2014;9:94-103.
37. Adline Princy S, Vinod kannan R, Bharath D, Vasudevan R. Studies on epidemiology and screening of a quorum quencher from Melia dubia against urinary tract infections during pregnancy. BioTechnol: Indian J 2014;9:48-55.
262 Views | 752 Downloads
How to Cite
Ravichandiran, V., H. M, and A. P. S. “INHIBITORS FROM MELIA DUBIA AGAINST SDIA MEDIATED QUORUM SENSING OF UROPATHOGENIC E. COLI”. International Journal of Pharmacy and Pharmaceutical Sciences, Vol. 7, no. 13, Sept. 2015, pp. 161-6,