# Chemical Composition, Nutritional Profile, and Bioactive Properties of Diplotaxis tenuifolia, a Health-Promoting Food

## TL;DR

This study explores the nutritional and bioactive properties of Diplotaxis tenuifolia, showing it is rich in minerals, antioxidants, and unique compounds, making it a promising health-promoting food.

## Contribution

The first comprehensive characterization of D. tenuifolia's chemical composition and bioactive properties, including the first report of sulfoglucobrassicin in this species.

## Key findings

- D. tenuifolia leaves are rich in essential minerals and dietary fiber with low heavy metal content.
- Phenolic compounds extracted in 80% methanol showed high antioxidant activity and included novel compounds like sulfoglucobrassicin.
- The plant contains unique fatty acids and bioactive molecules not previously reported in this species.

## Abstract

Diplotaxis tenuifolia (Brassicaceae), valued for its culinary use and bioactive potential, has not yet been comprehensively characterized in terms of its chemical composition and biological properties. This study investigated the nutritional profile, phytochemical composition, and antioxidant activity of D. tenuifolia cultivated in Portugal. The leaves contain substantial levels of essential minerals, particularly calcium, potassium, magnesium, iron, manganese, and chromium, while heavy metal levels were below regulatory safety limits. The nutritional profile also revealed high dietary fiber content, enriched glutamic and aspartic acids in the protein fraction, and α-linolenic acid as the predominant fatty acid. Phenolic compounds were most efficiently extracted by boiling them in 80% methanol, yielding the highest total phenolic (125.41 mg gallic acid equivalents g−1) and flavonoid contents (3.72 mg quercetin equivalents g−1). HPLC-PDA-ESI-MSn analysis enabled the detailed characterization of phenolic acids, flavonol glycosides, and glucosinolates, highlighting the first report of sulfoglucobrassicin in D. tenuifolia. Additionally, 6-methylsulfonyl-3-oxohexyl-glucosinolate, proline, pipecolic acid, glucaric acid, eicosanoic acid, 9,10,12,13-tetrahydroxy-octadecanoic acid (sativic acid) and 9,12,13-trihydroxyoctadec-10-enoic acid were described for the first time in this species. The extract exhibited also antioxidant activity, with ABTS IC50 57.54 ± 0.18 µg mL−1, DPPH IC50 302.73 ± 2.36 µg mL−1, and FRAP 752.71 ± 4.59 µmol eq. Fe(II) g−1. These findings establish D. tenuifolia as a nutritionally rich plant and a promising source of natural antioxidants for nutraceutical and pharmaceutical applications.