Study of the antioxidant properties and stability of Eucalyptus globulus and Calendula officinalis extracts for synthetic additive replacement.

DOS SANTOS, CRISTINA; PATRIARCA, ANDREA; PEREYRA GONZALES, ADRIANA; ABRAM, VERÓNIKA; POKLAR ULRIH, NATASA; BUERA, MARÍA DEL PILAR; MAZZOBRE, MARÍA FLORENCIA

Buenos Aires

Conferencia; VI International Conference on Polyphenols and Health (ICPH 2013).; 2013

Plant extracts have emerged as sources of natural antioxidants for food formulations to replace synthetic additives that are currently being questioned by consumers. Eucalyptus leaves, oil, fruits and barks and marigold flowers have been used in traditional medicine due to their antinflamatory, antibacterial and analgesic properties. The aim of this work was to determine the experimental conditions to maximize the polyphenols extraction from eucalyptus dried leaves extracts (Eucalyptus Globulus) and from marigold dried flowers (Calendula officialis) and also to analyze the relationship between polyphenols content and antioxidant activity. Extracts were obtained by stirring in water-methanol and water-ethanol solutions. After vacuum evaporation of solvents, extracts were freeze-dried and stored under nitrogen atmosphere. UV-Vis spectra of samples were determined in the range 800-200 nm. Total phenolic content (TPC) was evaluated by Folin?Ciocalteu and the antioxidant capacity (AOC) by HPLC with electrochemical detector and by DPPH assay. The maximum polyphenol content was achieved in methanol-water 70:30. A direct correlation between the amount of TPC and AOC was observed for all the analyzed extracts. Eucalyptus showed higher absorbance at  300-270 nm, and higher TPC contents and AOC than marigold extracts. Eucalyptus extracts could be sources of antioxidants to employ in the formulation of functional ingredients.