Ontogenetic changes in phenolic contents and volatile composition of Hypericum androsaemum and Hypericum xylosteifolium

Tocopherol and Tocotrienol Content in the Leaves of the Genus Hypericum: Impact of Species and Drying Technique

α-Tocopherol (α-T) predominates in photosynthetic tissues, while tocotrienols (T3s) are reported very rarely. The genus Hypericum stands out as one of the few exceptions. Given the potential health benefits associated with tocotrienols, sourcing them from natural origins is of interest. The proper selection of plant material and the drying conditions are crucial steps in this process. Therefore, in the present study, we investigated the effects of four different drying techniques (freeze-drying, microwave-vacuum-, infrared oven and air-drying) on the tocochromanol content in leaves of three Hypericum species: H. androsaemum, H. pseudohenryi, and H. hookerianum and one hybrid H. × inodorum. The total tocochromanol content in the freeze-dried leaves harvested in September was 68.1-150.6 mg/100 g dry weight. α-T constituted 66.7-85.9% (w/w), while tocotrienols constituted 13-32% (w/w). H. pseudohenryi was characterized by the lowest tocotrienol content, while H. androsaemum and H. hookerianum had the highest, with δ-T3 and γ-T3, respectively, being predominant. Tocotrienols were more stable during drying than α-T. The greatest decrease in α-T content was observed during air-drying in the presence of sunlight, with a 27% difference compared to the absence of sunlight. The species and harvest time are factors that more strongly affect the tocotrienol content in the Hypericum leaves than the selected drying method.

Functional, structural, and rheological properties of the complexes containing sunflower petal extract with dairy and plant-based proteins

This study aims to investigate the impact of sunflower petal extract (SFE) on the functional and structural properties of sodium caseinate and chickpea proteins. For this purpose, 3.5 % of sodium caseinate solution and 3.5 % of protein extracted from chickpea powder were prepared in phosphate buffer (pH = 7). SFE was used at different concentrations, from 1 to 3 % in different protein solutions and functional, structural and rheological properties were measured. The results revealed that complexation of SFE with different proteins can enhance the antioxidant, foaming properties, solubility, emulsion activity, emulsion stability, viscoelastic behavior, and can decrease surface hydrophobicity. FTIR and docking results showed that the most bonding type was non-covalent bonds. Major phenolic compounds containing heliannone A, B, and kaempferol had strong affinity with sodium caseinate, and then chickpea protein. Therefore, the results demonstrated that SFE and its complexes had appropriate emulsifying properties that reduces interfacial tension in the water/oil interface.

Hyperforin: A natural lead compound with multiple pharmacological activities

Hypericum perforatum L. (Clusiaceae), commonly known as St. John's wort, has a rich historical background as one of the oldest and most widely studied herbal medicines. Hyperforin is the main antidepressant active ingredient of St. John's wort. In recent years, hyperforin has attached increasing attention due to its multiple pharmacological activities. In this review, the information on hyperforin was systematically summarized. Hyperforin is considered to be a lead compound with diverse pharmacological activities including anti-depression, anti-tumor, anti-dementia, anti-diabetes and others. It can be obtained by extraction and synthesis. Further pharmacological studies and more precise detection methods will help develop a value for hyperforin. In addition, structural modification and pharmaceutical preparation technology will be beneficial to promoting the research progress of hyperforin based innovative drugs. Although these works are full of known and unknown challenges, researchers are still expected to make hyperforin play a greater value.

Novel Signposts on the Road from Natural Sources to Pharmaceutical Applications: A Combinative Approach between LC-DAD-MS and Offline LC-NMR for the Biochemical Characterization of Two Hypericum Species (H. montbretii and H. origanifolium)

The members of the genus Hypericum have great potential to develop functional uses in nutraceutical and pharmaceutical applications. With this in mind, we aimed to determine the chemical profiling and biological properties of different extracts (ethyl acetate, methanol and water) from two Hypericum species (H. montbretii and H. origanifolium). We combined two approaches (LC-DAD-MS and LC-NMR) to identify and quantify chemical compounds of the extracts. Antioxidant properties (free radical quenching, reducing power and metal chelating) and enzyme inhibitory effects (cholinesterase, tyrosinase, amylase and glucosidase) were determined as biological properties. The tested extracts were rich in caffeic acid derivatives and flavonoids, and among them, 3-caffeoyl quinic acid and myricetin-3-O-rhamnoside were found to be the main compounds. The total phenolic and flavonoid levels were determined to be 50.97-134.99 mg GAE/g and 9.87-82.63 mg RE/g, respectively. With the exception of metal chelating, the methanol and water extracts showed stronger antioxidant properties than the ethyl acetate extracts. However, different results were obtained for each enzyme inhibition assay, and in general, the ethyl acetate extracts present more enzyme-inhibiting properties than the water or methanol extracts. Results from chemical and biological analyses were combined using multivariate analysis, which allowed establishing relationships between composition and observed effects of the Hypericum extracts based on the extraction solvents. To gain more insights between chemical compounds and enzyme-inhibiting effects, we performed molecular docking analysis. We observed favorable interactions between certain compounds and the tested enzymes during our analysis, confirming the data obtained from the multivariate approach. In conclusion, the obtained results may shed light on the road from natural sources to functional applications, and the tested Hypericum species may be considered potential raw materials, with promising chemical constituents and biological activities.