# Antioxidant Activity of Different Phenolic‐Rich Fractions Obtained From Peels of Turkish Dark Purple Eggplant

## TL;DR

This study explores the antioxidant potential of phenolic compounds extracted from Turkish dark purple eggplant peels using various solvents and methods.

## Contribution

The study introduces a comparative analysis of different solvent systems and extraction methods for maximizing antioxidant activity from eggplant peels.

## Key findings

- Soxhlet extraction with absolute ethanol yielded the highest phenolic content and strongest antioxidant activity.
- Anthocyanin-rich fractions showed high anthocyanin content and significant antioxidant properties.
- Hot water bath extraction in an acidic medium effectively extracted flavonoid compounds.

## Abstract

This study investigated the extraction of phenolic compounds and the antioxidant potential of eggplant peel using various extraction methods and GRAS solvent systems. Ethanol absolute and (EtOH: water) (70:30) system solvents were used separately to extract phenolic compounds, while the (EtOH: water: citric acid) (70:30:0.5) system was utilized for anthocyanin extraction. Otherwise, to test the antioxidant activity of anthocyanin separately, an aqueous anthocyanin‐rich fraction was recovered from eggplant peel crude extract using successive liquid/liquid extractions with solvents of different polarities. The presence of total phenolics, anthocyanins and proanthocyanidin were detected, and HPLC analysis was realized. The antioxidant activity was performed by the (DPPH) free radicals method. Soxhlet extraction using absolute ethanol provides a high yield of phenolic compounds. Otherwise, the anthocyanin extract showed a high level of anthocyanin contents. The liquid chromatographic analysis presented an important percentage of flavonoids. Soxhlet extract was the most effective in scavenging free radicals.

Polyphenol contents of Turkish eggplant peels were extracted by different solvent systems and extraction methods. Liquid–liquid extraction was performed for anthocyanin separation. Qualitative and quantitative differences in phenolic profiles were observed. Soxhlet extraction by absolute ethanol showed the highest total phenolic content and strongest antioxidant activity. Hot water bath extraction with an acidic medium yielded a high extraction of flavonoid compounds.