Detailed investigation of the composition and transformations of phenolic compounds in fresh and fermented Vaccinium floribundum berry extracts by high-resolution mass spectrometry and bioinformatics

Phytochem Anal. 2022 Jun;33(4):507-516. doi: 10.1002/pca.3105. Epub 2022 Jan 21.

Abstract

Introduction: Blueberries are known for their very high content of biologically active phenolic compounds; nonetheless, differently from the North American and European species of blueberries, Neotropical blueberries have not been extensively studied yet.

Objectives: In the present paper, the phenolic composition of Vaccinium floribundum Kunth, which is endemic to the Andean regions and grows 1,600 to 4,500 meters above sea level, was investigated by ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS). Native and fermented berries were compared in terms of phenolic composition as well as antioxidant activity, total phenolic content, and total anthocyanin content.

Materials and methods: V. floribundum native and fermented berries were extracted and analyzed by UHPLC-HRMS. The acquired datasets were processed by Compound Discoverer 3.1 using a dedicated data analysis workflow that was specifically set up for phenolic compound identification.

Results: In total, 309 compounds were tentatively identified, including anthocyanins, flavonoids, phenolic acids, and proanthocyanidins. The molecular transformations of phenolic compounds during fermentation were comprehensively investigated for the first time, and by a customized data processing workflow, 13 quinones and quinone methides were tentatively identified in the fermented samples. Compared to other species of the genus Vaccinium, a peculiar phenolic profile is observed, with low abundance of highly methylated compounds.

Conclusion: Andean berries are a rich source of a wide variety of phenolic compounds. Untargeted MS analyses coupled to a dedicated data processing workflow allowed expanding the current knowledge on these berries, improving our understanding of the fate of phenolic compounds after fermentation.

Keywords: Compound Discoverer; Neotropical berries; blueberry; high-resolution mass spectrometry; polyphenols; quercetin quinone.

MeSH terms

  • Anthocyanins / analysis
  • Antioxidants / analysis
  • Chromatography, High Pressure Liquid
  • Computational Biology
  • Fruit / chemistry
  • Mass Spectrometry
  • Phenols / analysis
  • Plant Extracts / chemistry
  • Vaccinium* / chemistry

Substances

  • Anthocyanins
  • Antioxidants
  • Phenols
  • Plant Extracts