Gram-negative bacteria, silver nanoparticles

Sondi, I., Salopek-Sondi, B., 2004. Silver nanoparticles as antimicrobial agent a case study on E. coli as a model for Gram-negative bacteria. J. Colloid Interface Sci 275, 177-182. 

Lactonic sophorolipids exhibit antimicrobial activity and degree of antimicrobial activity is related to the structure of sophorolipids, which is determined by the type of carbon source used for fermentation." Sophorolipids derivatives such as sophorolipids diacetate ethyl ester derivatives have been reported as having spermicidal and virucidal activity and can be used in preparation of microbicidal contraceptions." Administration of sophorolipids reduces the mortality associated with septic shock in rats due their immunomodulatory function." Sophorolipids capped silver nanoparticles are very stable and show strong antimicrobial activity against gram-positive and gram-negative bacteria." ... 

To compare the bactericidal efficacy of silver nanoparticles and silver ions, the minimum inhibitory concentration (MIC) assays were conducted for gram-negative bacterium E. coli, gram-positive bacteria S. aureus and B. subtilis and fungus P. phoeniceum. The data on MICs are summarized in Table 18.1. The results demonstrated that the antimicrobial activity of silver ions was superior to that of silver nanoparticles against all microbes tested. 

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