Antimicrobical and antivirial impact of novel quercetin-enriched lecithin

Abstract

The antimicrobical and antiviral effects of native soy lecithin, quercetin and quercetin-enriched lecithin formulations were studied. The preparation of quercetin-enriched lecithin was described for the first time. In general, antimicrobial and antiviral activities of quercetin-enriched lecithin formulations were found to be better than individual lecithin or quercetin, most likely as a consequence of synergism between polar lipids and quercetin. Quercetin-enriched lecithin formulations exhibited strong antimicrobial action in comparison with native lecithin and quercetin. Increases in the concentration of quercetin in the formulation resulted in an increase in its antimicrobial activities. In addition, quercetin-enriched lecithin formulation (1:99, w/w) also showed high antibacterial activity against gram-positive bacteria with minimum inhibitory concentration between 750 and 1,000 μg/mL. Quercetin-enriched lecithin formulation (3:97 w/w) had a drastic effect on the biosynthesis of protein in cells of Bacillus subtilis, but the effect was slightly noted on the biosynthesis of DNA and RNA. The results are of great importance for improving the biological activity, functionality and health impact of commercial lecithin that could be applied in different food and pharmaceutical applications. PRACTICAL APPLICATIONS Plant phenolics, especially dietary flavonoids, are currently of growing interest, owing to their supposed functional properties in promoting human health. On the other side, phospholipids are used for many nutritional and pharmaceutical applications. In the current study, the preparation of quercetin-enriched lecithin is described for the first time. Antimicrobial and antiviral activities of quercetin-enriched lecithin formulations were shown to be superior to native lecithin and/or quercetin, most likely as a consequence of synergism between polar lipids and quercetin. The optimal concentration of quercetin-enriched lecithin formulation will depend on the actual application. Novel quercetin-enriched lecithin can be targeted for specific applications in functional foods, pharmaceuticals and cosmetics. © 2009, Wiley Periodicals, Inc.