In recent years, agro-industrial waste has been subject of many scientific research due to its high content of bioactive compounds, especially polyphenols, whose consumption is linked with various positive effects on human health. In this thesis, banana peel, part of a tropic fruit from the Musaceae family, has been chosen as a secondary plant material for the extraction of polyphenolic compounds using conventional (infusion, decoction, maceration) and innovative extraction methods (ultrasound-assisted extraction, microwave-assisted extraction, subcritical water extraction). Obtained extracts were characterized by determining the total polyphenols content, dopamine content and antioxidant capacity, and the extract with the best bioactive parameters was further used for encapsulation in liposomes. Formulated liposomes were characterized by determining the encapsulation efficiency and physico-chemical parameters. Infusion (80 °C, 30 min) showed to be most successful technique in the extraction of total polyphenols (25,38 mg EGK gˉ¹ dmb), and decoction (100 °C, 20 min) in dopamine extraction (12,63 mg EGK gˉ¹ dmb). Extract obtained by decoction was also characterized with the highest antioxidant capacity (0,196 and 0,164 mmol Trolox gˉ¹ dmb) and was further used for encapsulation in liposomes. Encapsulation of banana peel’s extract resulted in a relatively low encapsulation efficiency of dopamine (35,10 – 41,12 %). Measured values of size, zeta potential and polydispersion index indicate the relative homogeneity and uniformity of the formulated liposomes.