HRMS Profile of a Hazelnut Skin Proanthocyanidin-rich Fraction with Antioxidant and Anti-Candida albicans Activities

J Agric Food Chem. 2016 Jan 27;64(3):585-95. doi: 10.1021/acs.jafc.5b05404. Epub 2016 Jan 15.


Roasted hazelnut skins (RHS) represent a byproduct of kernel industrial processing. In this research, a RHS extract (RHS-M) and its fraction RHS-M-F3 enriched in proanthocyanidins (PAs), with antioxidant activity, were characterized in terms of total phenolic compound and PA contents. RHS-M and RHS-M-F3 showed antifungal properties against Candida albicans SC5314 (MIC2 = 3.00 and 0.10 μg/mL and MIC0 = 5.00 and 0.50 μg/mL, respectively), determined by the microbroth dilution method and Candida albicans morphological analysis. No cytotoxic effect on HEKa and HDFa cell lines was exhibited by RHS-M and RHS-M-F3. The metabolite profiling of RHS-M and RHS-M-F3 was performed by thiolysis followed by HPLC-UV-HRMS analysis and a combination of HRMS-FIA and HPLC-HRMS(n). Extract and fraction contain oligomeric PAs (mDP of 7.3 and 6.0, respectively, and DP up to 10) mainly constituted by B-type oligomers of (epi)-catechin. Also, (epi)-gallocatechin and gallate derivatives were identified as monomer units, and A-type PAs were detected as minor compounds.

Keywords: Candida albicans; HPLC-HRMSn analysis; HRMS flow injection analysis; hazelnut skins; industry byproducts; proanthocyanidins.

MeSH terms

  • Antifungal Agents / chemistry*
  • Antifungal Agents / pharmacology
  • Antioxidants / chemistry*
  • Antioxidants / pharmacology
  • Candida albicans / drug effects*
  • Candida albicans / growth & development
  • Chromatography, High Pressure Liquid
  • Corylus / chemistry*
  • Mass Spectrometry
  • Plant Extracts / chemistry*
  • Plant Extracts / pharmacology
  • Proanthocyanidins / chemistry*
  • Proanthocyanidins / pharmacology
  • Seeds / chemistry


  • Antifungal Agents
  • Antioxidants
  • Plant Extracts
  • Proanthocyanidins
  • proanthocyanidin