Chemical Characterization and Antioxidant Activity of Nine Hypericum Species from Greece

Abstract

Hypericum L. comprises about 500 species distributed almost worldwide. Research has mainly focused on H. perforatum with confirmed biological activity on the alleviation of depression symptoms, among others. The compounds responsible for such activity are considered naphthodianthrones and acylphloroglucinols. Other Hypericum species are less studied or not studied, and further research is needed to complete the characterization of the genus. In this study we evaluated the qualitative and quantitative phytochemical profile of nine Hypericum species native to Greece, namely H. perforatum, H. tetrapterum, H. perfoliatum, H. rumeliacum subsp. apollinis, H. vesiculosum, H. cycladicum, H. fragile, H. olympicum and H. delphicum. Qualitative analysis was performed using the LC/Q-TOF/HRMS technique, while quantitative data were calculated with the single point external standard method. Additionally, we estimated the antioxidant activity of the extracts using DPPH and ABTS assays. Three species endemic to Greece (H. cycladicum, H. fragile, H. delphicum) were studied for the first time. Our results indicated that all studied species are rich in secondary metabolites, mainly of the flavonoids family, with strong antioxidant activity.

The In Vitro Assessment of Antibacterial and Antioxidant Efficacy in Rosa damascena and Hypericum perforatum Extracts against Pathogenic Strains in the Interplay of Dental Caries, Oral Health, and Food Microbiota

“…In our study, the aqueous extracts of R. damascene showed the highest values of scavenging activity, following by ethanolic and enzymatic extracts ( Table 3 ). This is perfectly consistent with the fact that the aqueous extracts had recorded high values of total phenolics content, strengthening the hypothesis expressed by researchers in previous studies, that the difference in the free radical scavenging activity of extracts is based on their chemical composition and content of total phenols and flavonoids [ 88 , 90 ]. Despite variations in extraction methods, all extract types exhibited noteworthy antioxidant capacity.…”

Comprehensive Bio-Screening of Phytochemistry and Biological Capacity of <em>Oregano </em>(<em>Origanum vulgare</em>) and <em>Salvia triloba</em> Extracts against Oral Cariogenic and Food-Origin Pathogenic Bacteria

“…This trend persisted across ethanolic and aqueous extracts, with the lowest activity observed in the latter. This indicates that variations in the free radical scavenging activity of extracts are strongly linked to both their chemical composition and the levels of total phenols and flavonoids, which are also concentration dependent [68,69]. High levels of Total Phenolic Content (TPC) and Total Flavonoid Content (TFC) were observed in Oreganoʹ extracts, supporting previous research suggesting a correlation between antioxidant activity and phenolic/flavonoid levels [70,71].…”

Comprehensive Bio-Screening of Phytochemistry and Biological Capacity of Oregano (Origanum vulgare) and Salvia triloba Extracts against Oral Cariogenic and Food-Origin Pathogenic Bacteria

“…This trend persisted across ethanolic and aqueous extracts, with the lowest activity observed in the latter. This indicates that variations in the free radical scavenging activity of extracts are strongly linked to both their chemical composition and the levels of total phenols and flavonoids, which are also concentration-dependent [ 68 , 69 ]. High levels of total phenolic content (TPC) and total flavonoid content (TFC) were observed in Oregano extracts, supporting previous research suggesting a correlation between antioxidant activity and phenolic/flavonoid levels [ 70 , 71 ].…”