Rop O., Řezníček V., Mlček J., Juríková T., Balík J., Sochor J., Kramářová D., 2011. Antioxidant and radical oxygen species scavenging activities of 12 cultivars of blue honeysuckle fruit. Hort. Sci. (Prague), 38: 63-70.The fruit of blue honeysuckle (Lonicera caerulea L. var. kamtchatica (Sevast.) Pojark.) belongs to the fruit of great value because of itsunique chemical composition. The aim of our measurement of this fruit species was to select the cultivars which could be the most suitable food supplement in relation to strengthening human immunity system. The comparison of the fruit of 12 cultivars was made. The highest contents of polyphenolic substances were recorded in the cultivar Zolushka with the value of 9.03 g of gallic acid/kg fresh mass. In particular cultivars the DPPH (2,2-diphenyl-1-picrylhydrazyl) test was performed to determine antioxidant activity which ranged from 6.59-10.17 g of ascorbic acid equivalent/kg fresh mass. For comparison, scavenging activity of reactive oxygen species (superoxide anion, hydroxyl radical, and nitric oxide) was determined by using a 25% methanolic extract of fruit of particular cultivars. Antioxidant potential was also assessed using the rat liver slice model. The highest values of scavenging activity were found in the cultivars Zolushka, Goluboe vreteno, and Gerda. The cultivars Zolushka, Goluboe vreteno, and Gerda had also high values of flavonoids. The presented results may be used when popularizing this fruit species and also when studying the properties of new food and genetic resources.