The Oxidation Mechanism of Flavan-3-ols by an Enzymatic Reaction Using Liquid Chromatography-Mass Spectrometry-Based Metabolomics Combined with Captured o-Quinone Intermediates of Flavan-3-ols by o-Phenylenediamine

Zha M., Lian L., Wen M., Ercisli S., Ren Y., Jiang Z., ...Daha Fazla

JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, cilt.70, sa.18, ss.5715-5727, 2022 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 70 Sayı: 18
  • Basım Tarihi: 2022
  • Doi Numarası: 10.1021/acs.jafc.2c01416
  • Dergi Adı: JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Analytical Abstracts, Applied Science & Technology Source, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, Chimica, Compendex, EMBASE, Environment Index, Food Science & Technology Abstracts, MEDLINE, Pollution Abstracts, Veterinary Science Database, DIALNET
  • Sayfa Sayıları: ss.5715-5727
  • Anahtar Kelimeler: tea oxidation, o-phenylenediamine, theaflavins, theasinensins, BLACK TEA, EPIGALLOCATECHIN, THEARUBIGINS, IDENTIFICATION, THEAFLAVIN, FERMENTATION, POLYPHENOLS, EPICATECHIN, PYROGALLOL, PRODUCTS
  • Atatürk Üniversitesi Adresli: Evet

Özet

During the enzymatic oxidation of black tea, flavan-3-ols undergo a complicated chemical transformation and generate theaflavins and thearubigins. So far, the oxidation mechanism of flavan-3-ols has not been clarified. Liquid chromatography-tandem mass spectrometry-based metabolomics combined with o-quinone intermediates captured by o-phenylenediamine was developed and successfully applied in the liquid incubation of fresh tea homogenates. During the oxidation, the contents of catechins continuously decreased, while theaflavins increased first but decreased subsequently at the end of incubation. Meanwhile, the content of thearubigins greatly increased at the late stage of incubation. Dehydrotheasinensins were accumulated at the end of oxidation along with the decrease of theasinensins. Through o-phenylenediamine derivation, several adducts of (-)-epigallocatechin gallate, (-)-epigallocatechin, theasinensins A, B, C, and D, and corresponding dehydrotheasinensins were identified, which were considered as the substrates of thearubigins. These results suggested that theaflavins and these oxidation products contributed to the formation of thearubigins.