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The measurement of antiradical activity of some plant raw materials and extracts with use of TAU734 (Total Antiradical Unit)

100%

Wojtasik S., Sroka Z., Zbikowska B., Drys A.

Herba Polonica

2011

tom 57

nr 4

The aim of this work was to measure the antiradical activity of plant extracts and plant raw materials with use of TAU734 (total antiradical unit). For the study, three raw materials were used: oak bark (Quercus cortex) rich in tannins, inflorescence of hawthorn (Crataegi inflorescentia) rich in flavonoids and seeds of coffee (Coffeae semen) rich in phenolic acids (caffeic, chlorogenic acids). The methanol-water (1:1) extract was obtained from each raw material. A part of the extract was evaporated under reduced pressure to obtain dry extract A. The remaining part of methanol-water extract was submitted for further extraction and evaporation in order to obtain final dry extracts B (precipitate), C (ethyl acetate) and D (remaining aqueous). The antiradical activity was measured using ABTS•+ radical (2,2’-azino-bis (3-ethylbenzothiazoline- 6-sulfonic acid) diammonium salt). Antiradical potential was demonstrated as a number of antiradical units per mg of extract (TAU734/mg) and g of raw materials (TAU734/g). The highest number of antiradical units per g of raw material (TAU734/g - 13837±1726) was noticed for bark of oak. The weakest antiradical properties were observed for seeds of coffee (TAU734/g - 5929±856). The largest number of antiradical units (TAU734/mg - 99.6±15.9) was noticed for mg of extract Bo from bark of oak. The weakest antiradical properties (TAU734/mg - 16.0±2.0) exhibited extract Bc from seeds of coffee.

Antiradical activity and amount of phenolic compounds in extracts obtained from some plant raw materials containing methylxanthine alkaloids

100%

Sroka Z., Janiak M., Drys A.

Herba Polonica

2015

tom 61

nr 3

Raw materials containing methylxanthine alkaloids such as yerba mate, guaraná, white and green tea, coffee seeds, chocolate and cacao seed powder and extracts obtained from these raw materials were investigated for their antioxidant features and the amount of phenolic compounds. The level of phenolic compounds was measured with the colorimetric method using Folin-Ciocalteu’s phenol reagent and antioxidant features was determined with the use of DPPH (2,2-diphenyl-1-picrylhydrazyl radical). Amounts of phenolic compounds were presented in percentages per mass of extracts and mass of raw materials. Antiradical potential was shown as the number of TAUDPPH units per mg of extracts and g of raw materials. The highest number of antiradical units TAUDPPH as well as the amount of phenolic compounds was calculated for white tea and its extracts and lowest for chocolate. The correlation coefficient between the content of phenolics and antiradical features of raw materials is equal to r=0.994.

Ograniczanie wyników

2 Herba Polonica

2 Drys A.

2 Sroka Z.

1 Janiak M.

1 Wojtasik S.

1 Zbikowska B.

1 2015

1 2011

Wyniki wyszukiwania

The measurement of antiradical activity of some plant raw materials and extracts with use of TAU734 (Total Antiradical Unit)

Antiradical activity and amount of phenolic compounds in extracts obtained from some plant raw materials containing methylxanthine alkaloids