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V doktorski disertaciji smo preučili vpliv različnih biotehnoloških procesov (kaljenja, fermentacije, encimske obdelave) na vsebnost in dostopnost ekstraktibilnih in vezanih fenolnih spojin v semenih pire in na njihovo in vitro ter in vivo antioksidativno aktivnost. Glavne identificirane fenolne spojine v pirinih semenih so bile ferulna, p-kumarna, kavna in p-hidroksibenzojska kislina. Pri iskanju optimalnih pogojev abiotskega stresa med kaljenjem semen za čim večji prirast fenolov, je kaljenje pri povečani slanosti in osmolarnosti brez aplicirane mehanske poškodbe najbolj povečalo vsebnost fenolnih spojin in izboljšalo njihovo antioksidativno aktivnost. Kombiniranje različnih biotehnoloških procesov predstavlja bistveno učinkovitejši način za povečanje vsebnosti fenolnih spojin kot posamezen proces. Največjo absolutno vsebnost ekstraktibilnih in vezanih posameznih fenolnih kislin smo določili v kaljenih semenih, fermentiranih s S. cerevisiae. Nadalje je obdelava kaljenih in fermentiranih semen s petimi hidrolitičnimi encimi znatno povečala vsebnost ekstraktibilnih fenolnih spojin, hkrati pa je imela negativen vpliv na vsebnost vezanih fenolnih spojin. Fenolne spojine iz kaljenih semen niso zaščitile modelnega organizma S. cerevisiae pred oksidacijo, medtem ko je večina ekstraktibilnih fenolnih spojin iz fermentiranih in encimsko obdelanih semen znižala znotrajcelično oksidacijo. Večji celični privzem fenolnih spojin ne pomeni nujno tudi večje antioksidativne aktivnosti in vivo, poleg količine je pomembna tudi oblika fenolnih spojin, ki vstopajo v celico. Rezultati kažejo na spremembe v sestavi ekstraktov med simulirano in vitro prebavo, saj so antioksidanti istega ekstrakta pokazali drugačen odziv proti različnim prostim radikalom v primerjavi z neobdelanimi semeni. Največjo vsebnost biološko dostopnih fenolnih spojin smo ugotovili v kaljenih semenih, fermentiranih s S. cerevisiae. Izgube fenolnih spojin po prebavi so bile velike, kljub temu pa so biološko obdelana semena imela še vedno znatno večjo vsebnost fenolnih spojin v primerjavi z neobdelanimi semeni. Within the scope of the doctoral dissertation, we investigated the influence of different biotechnological processes (germination, fermentation, enzymatic treatment) on the content and accessibility of extractable and bound phenolic compounds in spelt seeds, as well as on their antioxidant activity in vitro and in vivo. The major phenolic compounds identified in spelt seeds were ferulic, p-coumaric, caffeic and p-hydroxybenzoic acids. When searching for the optimal conditions of abiotic stress during seed germination to produce the greatest increase in phenolics, germination at increased salinity and osmolarity without applied mechanical damage showed the highest increase in phenolic compounds content and antioxidant activity. Combining different biotechnological processes represents the more effective way to increase the content of phenolic compounds than a single process. The highest absolute content of extractable and bound individual phenolic acids was found in germinated seeds fermented with S. cerevisiae. Moreover, treatment of germinated and fermented seeds with five hydrolytic enzymes significantly increased the content of extractable phenolic compounds, but at the same time had a negative effect on the content of bound phenolic compounds. Phenolic compounds of germinated seeds could not protect the model organism S. cerevisiae from oxidation, whereas most extractable phenolic compounds from fermented and enzymatic treated seeds reduced intracellular oxidation. Greater cellular uptake of phenolic compounds does not necessarily mean greater antioxidant activity in vivo, in addition to the quantity, the form of phenolic compounds entering the cell is also important. The results suggest changes in the composition of the extracts during simulated in vitro digestion, since antioxidants of the same extract showed a different response against various free radicals compared to the raw seeds. The highest content of bioaccessible phenolic compounds was found in germinated seeds fermented with S. cerevisiae. Losses of phenolic compounds after digestion were high, however, the bioprocessed seeds still contained higher content of phenolic compounds compared to raw seeds.