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Zaradi vse večjega ozaveščanja o zdravi prehrani se vse pogosteje raziskujejo vplivi različnih snovi v sadju in zelenjavi na zdravje. Predvsem je poudarek na fenolnih spojinah, ki vplivajo na zmanjšanje verjetnosti obolenja za rakom in boleznim srca in ožilja. Ker so plodovi žlahntega jagodnjaka zelo priljubljeni pri potrošnikih in vsebujejo precej teh snovi, smo se odločili, da primerjamo tri rdečeplodne sorte žlahtnega jagodnjaka ('Clery', 'Albion' in 'Eliany') z dvema beloplodnima ('Natural albino' in 'Snow white') sortama. Izmerili smo maso plodov, njihovo trdoto ter barvne parametre. V plodovih smo analizirali vsebnosti sladkorjev, vitamina C, organskih kislin in fenolih spojin. Pri masi plodov so bili statistično značilno najtežji plodovi sorte 'Albion', najlažji pa plodovi sorte 'Natural albion'. Najmehkejši sorti sta bili 'Natural albino' in 'Snow white', ki sta bili mehkejši kar za tri do štiri krat od sorte 'Albion'. Pokazalo se je, da med vsebnostjo skupnih fenolov ni bilo razlik med sortami. Skupnih sladkorjev so največ vsebovali plodovi pri sorti 'Natural albino'. V vsebnosti skupnih organskih kislin med sortami ni bilo razlik. Vsebnost vitamina C je za 24 % večja v plodovih sorte 'Natural albino', kot v plodovih sorte 'Eliany', kjer je bila vsebnost najmanjša. Od vseh fenolnih spojin so plodovi obeh belih sort vsebovali več le flavanonov (sorta 'Natural albino') in derivatov hidroksicimetnih kislin (sorta 'Snow white'), ki predstavljajo le majhen odstotek skupnih analiziranih fenolnih spojin. Plodovi belih sort so vsebovali antocianine le v sledovih. Plodovi sorte 'Eliany' so vsebovali v povprečju več derivatov hidroksibenzojskih kislin in flavanolov. Plodovi sorte 'Clery' so vsebovali največ flavonov. Flavonolov so največ vsebovali plodovi sort 'Clery' in 'Albion'. The awareness of eating healthy food is rising, because of that, there is more studies about influences of different substances in fruits and vegetables on health. The emphasis is on phenolics. They are reducing the chance of some cardiovascular disease and cancer. Because the strawberries are very popular at consumers and they contain a lot of phenolics, we decided that we will compare three red fruited cultivars ('Clery', 'Albion' and 'Eliany') and two white fruited cultivars ('Natural albino' and 'Snow white'). We measured mass, hardness, and colour parameters and analyzed sugars, organic acids, vitamin C and phenolic compounds. The highest fruit mass had cultivar 'Albion' and the lowest 'Natural albino'. The softest fruits had cultivars 'Natural albino' and 'Snow white'. They were three to four times softer than the 'Albion' which had the most firm fruits. The results showed that there is no difference in content of total phenolic contents. Cultivar 'Natural albino' had the highest content of total sugars. There were no differences between cultivars in total organic acids. The highest content of vitamin C had fruits of 'Natural albino' (for 24% more than 'Eliany'), while 'Eliany' had the lowest. White cultivars had highest content of flavanones ('Natural albino') and derivates of hidroxycinnamic acids ('Snow white'). Cultivar 'Eliany' had higher content of hydroxybenzoic derivatives and flavanols. The highest content of flavones had cultivar 'Clery'. Flavonols content was the highest in cultivars 'Clery' and 'Albion'.

V diplomskem delu smo opisali razlike v vsebnostih vitamina C, prevladujočih sladkorjev, organskih kislin in fenolnih spojin med žlahtnim jagodnjakom (Fragaria × ananassa Duch.) in navadnim jagodnjakom (Fragaria vesca L.). Iz znanstvenih člankov in strokovnih knjig sem ugotovila, da je skupnih fenolov več v navadnem jagodnjaku in posledično je pri njem večja antioksidativna sposobnost plodov. V navadnem jagodnjaku so po vsebnosti prevladujoči flavonoli in elagna kislina. Vsebnosti vitamina C v plodovih so primerljive pri obeh rastlinskih vrstah. Od raziskovanih organskih kislin prevladujeta citronska in jabolčna kislina. Navadni jagodnjak ima večjo vsebnost skupnih organskih kislin kot nekatere sorte žlahtnega jagodnjaka. V plodovih je po vsebnosti glavni sladkor fruktoza, sledita ji glukoza in saharoza. Med vsebnostmi preučevanih sladkorjev med obema vrstama ni večjih razlik. Zagotovo pa so vsebnosti primarnih in sekundarnih metabolitov odvisne od rastišča in podnebja, zato lahko vrednosti analiziranih snovi variirajo zaradi vpliva okoljskih dejavnikov. The aim of my thesis was to evaluate the differences in vitamin C content, the predominant sugars, organic acids and phenolic compounds between the garden strawberry (Fragaria × ananassa Duch.) and wild strawberry (Fragaria vesca L.). According to scientific articles and professional books wild strawberry has higher total phenolic content in comparison to garden strawberry and has consequently higher antioxidant activity. The prevailing phenolic compounds in wild strawberry are flavonols and elagic acid. Vitamin C content is comparable between the two plant species. Citric and malic acid are prevalent among studied organic acids. The wild strawberry has higher content of total organic acids in comparison with some of the cultivars of garden strawberry. The major sugar in fruits is fructose followed by glucose and sucrose. There are no major differences between the contents of the sugars between the two species. The contents of primary and secondary metabolites greatly depend on the growing location and the climate, so the values of the analyzed compounds can vary due to the impact of environmental factors.