Phytochemical Composition and Antitumor Activities of New Salad Greens: Rucola (Diplotaxis tenuifolia) and Corn Salad (Valerianella locusta)

Plant Foods Hum Nutr. 2016 Jun;71(2):197-203. doi: 10.1007/s11130-016-0544-7.

Abstract

D. tenuifolia and V. locusta, two greens, were analyzed for active compounds and antitumor actions on colorectal cancer cells. Phenolics were determined by UHPLC-Orbitrap-MS; carotenoids and glucosinolates by HPLC-MS; and sterols and fatty acids by gas-liquid chromatography (GLC). For antitumor effects, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) tests were run on HT-29 colorectal cancer cells, and in CCD-18 untransformed enterocyte cells. Six main carotenoids were identified in both vegetables, while total carotenoids accounted for 3520 and 2970 μg · g(-1) dry weight in D. tenuifolia and V. locusta, respectively. Six phenolics were detected in D. tenuifolia (68,600 μg · g(-1) dry weight) and five in V. locusta (139,000 μg · g(-1) dry weight). Three glucosinolates (GSL) were found in D. tenuifolia (1960 μg · g(-1) dry wt. total). Low-polarity extracts from V. locusta and D. tenuifolia showed IC50 ~ 150 and ~200 μg · mL(-1) on HT-29 cells, while both plants lacked actions on CCD-18 cells. V. locusta inhibited HT-29 cancer cells viability more efficiently than D. tenuiofolia, but induced less cytotoxicity. This work highlights the importance of functional foods for colorectal cancer prevention.

Keywords: Bioactive compounds; Cytotoxicity; Diplotaxis tenuifolia; HT-29 colorectal cancer cells; Valerianela locusta.

MeSH terms

  • Antineoplastic Agents / analysis
  • Antineoplastic Agents / pharmacology*
  • Brassicaceae / chemistry*
  • Carotenoids / analysis
  • Colorectal Neoplasms / prevention & control*
  • Fatty Acids / analysis
  • Flavonoids / analysis
  • Functional Food*
  • Glucosinolates / analysis
  • HT29 Cells
  • Humans
  • Phenols / analysis
  • Phytochemicals / analysis
  • Phytochemicals / pharmacology*
  • Plant Leaves / chemistry
  • Sterols / analysis
  • Valerianella / chemistry*
  • Vegetables / chemistry

Substances

  • Antineoplastic Agents
  • Fatty Acids
  • Flavonoids
  • Glucosinolates
  • Phenols
  • Phytochemicals
  • Sterols
  • Carotenoids