Raziskave topnosti in antioksidativne aktivnosti izvlečka vej bele jelke (Abies alba)

Udovič, Maja (author), Kreft, Samo (mentor)

Raziskave izvlečka iz bele jelke so pripeljale do ugotovitve, da ima izvleček antiaterosklerotično, kardioprotektivno ter antipsoriastično delovanje in zmanjšuje post-prandialni glikemični odziv. Izvleček vsebuje ogljikove hidrate in polifenole, ki z znano biološko, farmakološko in klinično aktivnostjo prispevajo k delovanju. Naš namen je bil z metodama lovljenja DPPH• in ABTS•+ radikalov ugotoviti antioksidativno aktivnost v izvlečku iz vej bele jelke. Z modifikacijo metod, kjer za ugotavljanje antioksidativne aktivnosti namesto metanola uporabimo vodo, dobimo realnejšo sliko, kaj se po zaužitju izvlečka dogaja v našem telesu. Zanimivo je bilo spoznanje, da ob menjavi topila iz vode v metanol ali obratno pride do obarjanja določenih snovi, ki lahko vplivajo na antioksidativno aktivnost. Koncentracija reagentov vpliva na meritev antioksidativne aktivnosti. Najboljši parameter za ugotavljanje antioksidativnega delovanja z DPPH• metodo je za standarda galno kislino in kvercetin naklon premice, za izvlečka Belinal in Belinal C pa IC50. Za metodo ABTS•+ je za standarda in izvlečka naklon premice najboljši parameter. S centrifugiranjem in filtracijo smo ugotovili, da delež izvlečka, ki se raztopi, znaša od 37 % do 98 %, kar je odvisno od vrste vzorca, metode, topila ter od razmerja med topilom in vzorcem. Z metodo centrifugiranja smo ugotavljali, kolikšen delež vzorca je netopen v metanolu ali v vodi, netopen v obeh topilih ali topen v le enem topilu. Z metodo filtriranja smo preverjali topnost izvlečka v različnih razmerjih med izvlečkom in vodo ter 0,01 M HCl. Belinal je v obeh topilih bolje topen kot Belinal C. Na topnost in vsebnost antioksidantov v izvlečku lahko vpliva leto poseka, obdobje poseka vej, okolje, proces predelave vej in starost vzorca ob izvajanju testov, ker vsi ti dejavniki vplivajo na sestavo izvlečka.

• Language: Slovenian
• Keywords: antioksidanti, bela jelka, izvleček iz vej, topila, topnost
• Work type: Master's thesis/paper
• Organization: FFA - Faculty of Pharmacy
• Year: 2020
• PID: 20.500.12556/RUL-121727
• Publication date in RUL: 24.10.2020

Secondary language

• Language: English
• Title: Research on the solubility and antioxidant activity of white fir branch extract (Abies alba)

Abstract

Research on white fir extract has led to the conclusion that the extract has antiatherosclerotic, cardioprotective, antipsoriastic activity and reduces the postprandial glycemic response. It contains carbohydrates, tannins and polyphenols that contribute to anti-inflammatory activity with known biological composition, as well as pharmacological and clinical activity. Our task was to identify the antioxidant content of the white fir branch extract using the DPPH• radical scavenging assay and ABTS•+ radical scavenging assay methods. By modifying the methods by using water instead of methanol to determine the antioxidant content, we get a more realistic idea of what is going on in our bodies after ingesting the extract. It was interesting to learn that when the solvent is changed from water to methanol or vice versa, certain substances precipitate, that can affect antioxidant activity. The concentration of antioxidant reagents influences the determination of the amount of antioxidants. The best parameter for determining the antioxidant activity of the DPPH• method is the slope of the line for standard gallic acid and quercetin, the IC50 for Belinal and Belinal C extracts. For the ABTS•+ method, the slope of the line is the best parameter for the standard and the extract. By means of centrifugation and filtration it was found that the proportion of the extract was dissolved from 37 % to 98 %, depending on the type of sample, method, solvent, and the solvent to sample ratio. With the centrifugation method we determined the insoluble fraction in methanol or water, the insoluble fraction in both solvents and the soluble fraction in only one solvent. With the filtration method we examined the solubility of the extract in different proportions of the extract to water and 0,01 M HCl. Belinal is better soluble than Belinal C in both solvents. The solubility and antioxidant content of the extract may be affected by the year of harvest, the branch felling period, the environment, the processing of the branches and the age of the sample itself when performing the tests, since all these factors affect the composition of the extract.

• Keywords: antioxidants, white fir, branch extract, solvents, solubility