| Sažetak | U ovom je diplomskom radu provedena kvalitativna i kvantitativna analiza polifenolnih tvari u listovima lovora (Laurus nobilis L., Lauraceae), populacije sjevernog i srednjeg Jadrana: Lovran, Cres, Mali Lošinj, Dugi Otok, Žirje i Split. Prisutnost polifenolnih tvari dokazana je općim reakcijama stvaranja obojenih produkata i/ili taloga. Kvantitativna analiza ukupnih polifenola i trjeslovina provedena je spektrofotometrijskom metodom s Folin-Ciocalteuovim fenolnim reagensom. Sadržaj ukupnih polifenola bio je najveći u uzorku s otoka Žirja 7,45% (720 nm), odnosno 7,65% (749 nm), dok je najmanji polifenolni udio iznosio 6,07% (720 nm), tj. 6,23% (749 nm), a određen je u uzorcima s Dugog otoka. Najveća količina trjeslovina u ekstraktima listova lovora zabilježena je u uzorku Split (3,53%, 720 nm; 3,49%, 749 nm), dok je najmanji sadržaj trjeslovina određen za Dugi otok (1,77%, 720 nm; 1,85%, 749 nm). Provedena fitokemijska karakterizacija predstavlja prilog znanstvenom istraživanju roda Laurus, pridonosi dosadašnjim znanstvenim spoznajama o hrvatskim populacijama vrste Laurus nobilis L. te upotpunjuje dosadašnje spoznaje o fitoterapijskom potencijalu lovora. |
| Sažetak (engleski) | The qualitative and quantitative analysis of polyphenols in leaves of Laurus nobilis L., Lauraceae (northern and middle Adriatic populations: Lovran, Cres, Mali Lošinj, Dugi Otok, Žirje and Split) was carried out in this graduate thesis. The presence of polyphenols was proven by using general reactions of developing colored products and precipitates. The quantitative analysis of total polyphenols and tannins was performed by spectrophotometric method with the Folin-Ciocalteu’s phenol reagent. The content of total polyphenols was the largest in the sample from the island of Žirje 7.45% (720 nm) and 7.65% (749 nm), while the lowest polyphenol content was 6.07% (720 nm), i.e. 6.23 % (749 nm) and was measured in samples from Dugi otok. The highest amount of tannins in the leaves of laurel was recorded in Split (3.53%, 720 nm, 3.49%, 749 nm), while the smallest content was determined in the sample from Dugi otok (1.77%, 720 nm; 1.85%, 749 nm). This phytochemical characterization is a contribution to the scientific research of the genus Laurus, it also contributes to the study of the Croatian populations of Laurus nobilis L., completing the present knowledge of phytotherapeutic potential of the investigated herbal species. |
