associated with yield (number and size of inflorescences), chemical composition of inflorescences, growth characteristics, uniformity of flowering, and resistance to pests and diseases. Our studies indicate that interspecific hybridization efficiently increases the variation in the chemical composition of elderberry fruits (Mikulic-Petkovsek et al., 2014.Polyphenolic compounds are regarded as important chemical compounds due to their high antioxidant efficacy (Ozgen et al., 2010), which has a positive impact on people's health, and may impede the development of cancer and inhibit oxidative damage (Akbulut et al., 2009). Phenolic compounds possess various pharmacological effects: antiviral, antibacterial, antiinflammatory, and anticancer functions. Positive effects of flavonoids and phenolic acids have also been reported in connection with cardiovascular diseases (Olthof et al., 2001;Netzel et al., 2002;Murkovic et al., 2004). It has been reported that the concentration of phenolics is closely connected with the antioxidant activity of plant tissue and thus an assessment of the phenolic profile is important for the determination of antioxidant capacity (Choi and Kwak, 2014). The antioxidant activity of elderberry inflorescence extracts ranged from 44.8 to 118.2 mM TE/kg DW (Mikulic-Petkovsek et al., 2016).