Harvest time affects antioxidant capacity, total polyphenol and flavonoid content of Polish St John's wort's (Hypericum perforatum L.) flowers

• Published in: Scientific reports Vol. 11; no. 1; pp. 3989 - 12
• Main Authors: Makarova, Katerina, Sajkowska-Kozielewicz, Joanna J, Zawada, Katarzyna, Olchowik-Grabarek, Ewa, Ciach, Michał Aleksander, Gogolewski, Krzysztof, Dobros, Natalia, Ciechowicz, Paulina, Freichels, Hélène, Gambin, Anna
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 17.02.2021; Nature Publishing Group UK; Nature Portfolio
• Subjects: Anthracenes - chemistry; Antioxidants; Antioxidants - chemistry; Antioxidants - pharmacology; Benzhydryl Compounds - chemistry; Bisphenol A; Erythrocytes; Ethanol; Ethanol - chemistry; Flavonoids; Flavonoids - chemistry; Flowers; Flowers - chemistry; Harvesting; Humans; Hypericin; Hypericum - chemistry; Iron; NMR; Nuclear magnetic resonance; Perylene - analogs & derivatives; Perylene - chemistry; Phenols - chemistry; Phloroglucinol - analogs & derivatives; Phloroglucinol - chemistry; Plant Extracts - chemistry; Plant Extracts - pharmacology; Poland; Polyphenols - chemistry; Polyphenols - pharmacology; Principal Component Analysis; Principal components analysis; Terpenes - chemistry; Poland
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-021-83409-4

The polyphenol content and antioxidant capacity of hyperforin and hypericin-standardized H. perforatum L. extracts may vary due to the harvest time. In this work, ethanol and ethanol-water extracts of air-dried and lyophilized flowers of H. perforatum L., collected throughout a vegetation season in central Poland, were studied. Air-dried flowers extracts had higher polyphenol (371 mg GAE/g) and flavonoid (160 mg CAE/g) content, DPPH radical scavenging (1672 mg DPPH/g), ORAC (5214 µmol TE/g) and FRAP (2.54 mmol Fe /g) than lyophilized flowers extracts (238 mg GAE/g, 107 mg CAE/g, 1287 mg DPPH/g, 3313 µmol TE/g and 0.31 mmol Fe /g, respectively). Principal component analysis showed that the collection date influenced the flavonoid and polyphenol contents and FRAP of ethanol extracts, and DPPH and ORAC values of ethanol-water extracts. The ethanol extracts with the highest polyphenol and flavonoid content protected human erythrocytes against bisphenol A-induced damage. Both high field and benchtop NMR spectra of selected extracts, revealed differences in composition caused by extraction solvent and raw material collection date. Moreover, we have shown that benchtop NMR can be used to detect the compositional variation of extracts if the assignment of signals is done previously.