Middle East International Conference on Contemporary Scientific Studies-V, Ankara, Turkey, 27 - 28 March 2021, pp.474-479
Hypericum perforatum is a medicinal plant known as "sarı kantaron" in Turkey and “St. John's Wort" in Europe and America. It grows naturally in many countries of the world and blooms from July to September. It contains tannin, essential oils, flavone derivatives, hypericin, carotene and Vitamin C. Thanks to these antioxidant substances it contains, it can neutralize reactive oxygen species and prevent various damages that may occur as a result of oxidation. In this study, essential oil, extract and distilled water of St. John’s Wort were obtained by Clevenger apparatus. The samples were characterized by the determination of total phenolic content and antioxidant capacity. The total phenolic contents were determined by Folin-Ciocalteu method and also total antioxidant capacities of samples were determined by ABTS method. It was determined that the essential oil had better antioxidant properties. The protective powers of essential oil, extract and distillated water of St. John’s Wort against oxidatively induced DNA base damage were examined by gas chromatography triple quadrupole mass spectrometry (GC–MS/MS) relying on sensitive determination of the DNA base damage products. It was determined that the essential oil of St. John's Wort best protected DNA against oxidation.