Published in: Journal, Article, Research Support, Non-U.S. Gov’t, Volume : 67, Issue : 7, Pages : 951-962
DOI : 10.1111/jphp.12397
Author : Sarkar, Ratul; Mondal, Chaitali; Bera, Rammohan; Chakraborty, Sumon; Barik, Rajib; Roy, Paramita; Kumar, Alekh; Yadav, Kirendra K.; Choudhury, Jayanta; Chaudhary, Sushil K.; Samanta, Samir K.; Karmakar, Sanmoy; Das, Satadal; Mukherjee, Pulok K.; Mukherjee, Joydeep; Sen, Tuhinadri
Abstract : This study investigates the antimicrobial properties of Kalanchoe blossfeldiana with a particular reference to quorum sensing (QS)-mediated biofilm formation. A methanol extract of K. blossfeldiana leaves (MEKB) was evaluated for antimicrobial properties including QS-controlled production of biofilm (including virulence factor, motility and lactone formation) in Pseudomonas aeruginosa. The methanol extract of K. blossfeldiana was also evaluated for anti-cytokine (tumor necrosis factor-alpha, interleukin-6 and interleukin-1 beta) properties in peripheral blood mononuclear cells (PBMC). The methanol extract of K. blossfeldiana exhibited an antimicrobial effect on clin. isolates, as well as standard reference strains. Pseudomonas aeruginosa exposed to MEKB [subminimum inhibitory concentration (MIC)] displayed reduced biofilm formation, whereas supra-MIC produced destruction of preformed biofilms. The methanol extract of K. blossfeldiana reduced the secretion of virulence factors (protease and pyoverdin) along with generation of acyl homoserine lactone (AHL). Confocal laser scanning microscopy images indicate reduction of biofilm thickness. The extract also reduced cytokine formation in lipopolysaccharide-stimulated PBMC. Thus, Kalanchoe blossfeldiana was found to interfere with AHL production, which in turn may be responsible for downregulating QS-mediated production of biofilm and virulence.