20.500.12556/RUL-161398 Vrednotenje antioksidativne učinkovitosti izvlečka alg Dunalliela species Evaluation of Dunalliela species algae extract antioxidative activity različnimi spojinami s funkcionalnimi lastnostmi so antioksidanti med najbolj proučevanimi, saj je zanimanje za nove, varne in učinkovite antioksidante iz naravnih virov danes vse večje. Večina naravnih antioksidantov, ki se trenutno uporabljajo v kozmetični industriji, je pridobljenih iz kopenskih rastlin. Alge tako izkazujejo velik potencial kot alternativni vir antioksidantov. Alge Dunalliela sp. proizvajajo betakaroten, snov z antioksidativnim delovanjem. V okviru diplomske naloge smo vrednotili antioksidativno učinkovitost algnega izvlečka Dunalliela sp. Pri raziskovalnem delu smo uporabili dve metodi in vitro, in sicer difenilpikrilhidrazilno (DPPH) in feritiocianatno (FTC) pri čemer smo antioksidativne lastnosti algnega izvlečka primerjali z znanimi antioksidanti kot sta vitamin E in resveratrol. Za določanje antioksidativne učinkovitosti z DPPH metodo smo slednjo najprej prilagodili za optimalno določanje antioksidativne učinkovitosti algnega izvlečka. Pripravili smo več metanolnih in pufernih raztopin, od katerih je bila najbolj učinkovita raztopina algnega izvlečka v 5 mL 0,2 M fosfatnega pufra s pH 7. Rezultati raztopine algnega izvlečka so bili najbolj primerljivi z 0,01 % raztopino vitamina E in 0,003 % raztopino resveratrola. Pri izvedbi FTC metode smo v emulzijo z linolno kislino vgradili 20 % in 40 % raztopine algnega izvlečka v fosfatnem pufru. Obe koncentraciji sta bili sposobni zavirati lipidno peroksidacijo, pri čemer je bilo antioksidativno delovanje bolj izrazito v 40 % emulziji. Ob primerjavi z referenčnimi antioksidanti smo ugotovili, da je kinetika reakcije v prisotnosti raztopine algnega izvlečka drugačna. Antioksidativna učinkovitost algnega izvlečka je naraščala s časom obsevanja vzorcev, medtem ko so bili klasični antioksidanti najbolj učinkoviti v prvih dveh urah obsevanja vzorcev. Po osmih urah so testirane koncentracije antioksidantov in algnega izvlečka izkazovali primerljivo antioksidativno zaščito. V okviru diplomskega dela smo ugotovili, da algni izvleček Dunalliela sp. izkazuje antioksidativno učinkovitost, vendar ta ni tako močna kot antioksidativna učinkovitost nekaterih drugih antioksidantov. Izvleček Dunalliela sp. bi tako lahko uporabili v kozmetičnih izdelkih v kombinaciji z drugimi antioksidanti, kjer bi Dunalliela sp. izkazovala dolgotrajnejše delovanje kot kozmetično aktivna učinkovina, drugi vgrajeni antioksidanti pa bi zagotavljal oksidativno stabilnost izdelka. Among the various compounds with functional properties, antioxidants are among the most researched, as interest in new, safe and effective antioxidants from natural sources is growing nowadays. Most of the natural antioxidants used in the cosmetic industry are derived from terrestrial plants, but algae have shown potential as an alternative source of antioxidants. One such source is the alga Dunalliela sp., which is known to produce betacarotene, a substance with antioxidant activity. In the framework of the thesis, the antioxidant efficacy of algal extract of Dunalliela sp. was evaluated. Two in vitro methods were used, namely diphenylpicrylhydrazyl (DPPH) and ferricyanocyanate (FTC). For the determination of the antioxidant efficacy by the DPPH method, we had to first develop a suitable method, as no data were available on the efficacy of the algal extract. Several methanol and buffer solutions were prepared, the most effective of which was a solution of the algae in 5 mL of 0.2M phosphate buffer at pH 7. The extract of Dunalliela sp. was shown to be antioxidant effective. The results of the algae solution were more comparable with the 0,01 % vitamin E solution and the 0,003 % resveratrol solution. In the FTC method, 20 % and 40 % algal extract solutions were incorporated into the linoleic acid emulsion, which was prepared by dissolving the algal extract in 5 ml of 0.2 M phosphate buffer. Both concentrations were able be to inhibit lipid peroxidation, but the antioxidant activity was more pronounced in the emulsion containing 40 % algal extract. When compared with the reference antioxidants, we found that the kinetics of the reaction in the presence of the algal extract solution was different from that of the other antioxidants. The antioxidant efficacy of the algal extract increased with the irradiation time of the samples, whereas the conventional antioxidants were most effective during the first two hours of irradiation of the samples. After eight hours, the tested concentrations of antioxidants and algal extract showed comparable antioxidant protection. In our thesis, we found that the algal extract of Dunalliela sp. has antioxidant activity, but this is not as strong as that of some other antioxidants. Dunalliela sp. extract could be used in cosmetic products in combination with other antioxidants, where Dunalliela sp. would play the role of cosmetic active ingredient, while other antioxidants incorporated would ensure the oxidative stability of the product. Dunalliela species antioksidativna učinkovitost difenilpikrilhidrazilna metoda feritiocianatna metoda Dunalliela species antioxidant activity diphenylpicrylhydrazyl method ferricyanate method true false false Slovenski jezik Angleški jezik Diplomsko delo/naloga 2024-09-11 07:46:26 2024-09-11 07:46:30 2024-09-12 04:23:31 0000-00-00 00:00:00 2024 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 1970-01-01 107955 23440.pdf 23440.pdf 1 6141A2ABD931CF5012DAD60C9FC90D3C 4867fa34003469a589557c687dff838cdb004143d3a4c1dcc61de41d3fe4dadd 244b4dfc-7001-11ef-b232-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=190327 Fakulteta za farmacijo 0 0 0