The analysis of methylxanthine fractions obtained from Camellia sinensis cultivated in Turkey and effects on the in vitro inhibition of CYP2D6 enzyme


Biotechnology and Applied Biochemistry, 2022 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Publication Date: 2022
  • Doi Number: 10.1002/bab.2325
  • Journal Name: Biotechnology and Applied Biochemistry
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Applied Science & Technology Source, BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, Compendex, Computer & Applied Sciences, EMBASE, Environment Index, Food Science & Technology Abstracts, INSPEC, MEDLINE, Veterinary Science Database
  • Keywords: Black Sea tea, Camellia sinensis, in vitro inhibition, methylxanthines, CYP1A2, CYP3A4
  • Istanbul Technical University Affiliated: No


© 2022 International Union of Biochemistry and Molecular Biology, Inc.Tea is a worldwide consumed herbal beverage and it was aimed in this study to reveal the major fractions of green and black tea in order to enlighten the in vitro inhibition potency on the well-known drug metabolizing enzyme CYP2D6 activity. Methylxanthine fractions were extracted from green and black tea and a yield of 0.265 g (1.06%) for 25 g of dried black tea and 0.302 g (1.2%) for 25 g of green tea was calculated. High-performance liquid chromatography analysis represented that the major components of the methylxanthine fractions were caffeine, theobromine, and theophylline. Methylxanthine content of black tea was 368.25 ± 4.6 μg/ml caffeine, 89.30 ± 2.3 μg/ml theobromine, and 3.40 ± 0.5 μg/ml theophylline, whereas that of green tea was 176.50 ± 3.7 μg/ml caffeine, 53.85 ± 1.4 μg/ml theobromine, and 2.06 ± 0.7 μg/ml theophylline. The results of concentration-dependent inhibition studies were 76% green tea, 75% black tea, and 55% caffeine at concentration of 10 mg/ml. The inhibition rates of green and black tea on CYP2D6 activity were 76% and 75%, respectively, where that of quinidine, the well-known inhibitor of CYP2D6, was 82%. Our results indicate that green and black tea is very likely to modify the CYP2D6 enzyme activity.