# Evaluation of Decay Kinetics of Black Elderberry Antioxidants from Fruits and Flowers

## TL;DR

This study compares the antioxidant activity of black elderberry flowers and fruits, finding that flowers have higher antioxidant activity and that the process follows second-order reaction kinetics.

## Contribution

The study introduces the use of second-order reaction kinetics to describe the decay of radicals in black elderberry infusions.

## Key findings

- Flower infusions showed higher antioxidant activity than fruit infusions against DPPH and Glv radicals.
- The quenching of radicals by Sambucus nigra infusions follows second-order reaction kinetics.
- Flower infusions quenched radicals faster than fruit infusions.

## Abstract

The health-promoting properties of black elderberry are related to its high content of polyphenols (natural antioxidants), which eliminate free radicals and prevent the formation of oxidative stress responsible for many diseases. The aim of this work was to determine, the anti-radical effect of Sambucus nigra infusions based on the reaction with 2,2-diphenyl-1-picrylhydrazyl (DPPH) and galvinoxyl (Glv) radicals and to determine the function describing the disappearance curves of these radicals. The antioxidant properties of infusions obtained from the flowers and fruits of this plant were tested using the modified Brand-Williams method using DPPH and Glv radicals. Higher antioxidant activity towards both the DPPH and Glv radicals was found in flowers compared to fruits. In addition, it was found that the process of quenching radicals in the reaction with Sambucus nigra infusions proceeds in accordance with the assumptions of second-order reaction kinetics. The infusion obtained from flowers quenched radicals faster than fruit infusions. The applied second-order kinetics equation may enable estimation of antioxidants levels in natural sources of radicals.