Search results for "Phloroglucinol"
showing 10 items of 16 documents
In vitro bioactive properties of phlorotannins recovered from hydrothermal treatment of Sargassum muticum
2016
Abstract The present work addresses the potential of different adsorbents for the recovery of the phlorotannin fraction present in the liquid phase from the autohydrolysis of Sargassum muticum. Operating with the extract generated during autohydrolysis of alginate exhausted algae, the kinetics followed pseudo-second order and the equilibrium corresponded to Freundlich model. In batch configuration, up to 70% phlorotannins were adsorbed and up to 30% were desorbed with ethanolic solutions. Comparable performance was observed with the autohydrolysis extracts from the whole algae. The phloroglucinol content, the reducing and ABTS antiradical capacities of the desorbed product increased by 2–4 …
Arbuscular mycorrhizal fungi altered the hypericin, pseudohypericin, and hyperforin content in flowers of Hypericum perforatum grown under contrastin…
2016
St. John's Wort (Hypericum perforatum) is a perennial herb able to produce water-soluble active ingredients (a.i.), mostly in flowers, with a wide range of medicinal and biotechnological uses. However, information about the ability of arbuscular mycorrhizal fungi (AMF) to affect its biomass accumulation, flower production, and concentration of a.i. under contrasting nutrient availability is still scarce. In the present experiment, we evaluated the role of AMF on growth, flower production, and concentration of bioactive secondary metabolites (hypericin, pseudohypericin, and hyperforin) of H. perforatum under contrasting P availability. AMF stimulated the production of aboveground biomass und…
Variability of Hypericins and Hyperforin in Hypericum Species from the Sicilian Flora
2019
Within Sicilian flora, the genus Hypericum (Guttiferae) includes 10 native species, the most popular of which is H. perforatum. Hypericum's most investigated active compounds belong to naphtodianthrones (hypericin, pseudohypericin) and phloroglucinols (hyperforin, adhyperforin), and the commercial value of the drug is graded according to its total hypericin content. Ethnobotanical sources attribute the therapeutic properties recognized for H. perforatum, also to other Hypericum species. However, their smaller distribution inside the territory suggests that an industrial use of such species, when collected from the wild, would result in an unacceptable depletion of their natural stands. This…
A denuder-impinger system with in situ derivatization followed by gas chromatography-mass spectrometry for the determination of gaseous iodine-contai…
2008
Reactive iodine species have been suggested to play an important role in the atmosphere (e.g. tropospheric ozone depletion, coastal new particle formation). However, there still exist major uncertainties about their atmospheric chemistry, mostly due to the lack of analytical approaches for the accurate speciation of certain key compounds. In this study, 1,3,5-trimethoxybenzene (1,3,5-TMB)-coated denuder proved to be suitable for the differentiation between gaseous interhalogens (iodine monochloride (ICl), iodine monobromide (IBr)) and molecular iodine (I2) based on a selective collection/derivatization method. The results of the denuder sampling were compared with the results of impinger sa…
Aspidin PB, a phloroglucinol derivative, induces apoptosis in human hepatocarcinoma HepG2 cells by modulating PI3K/Akt/GSK3β pathway.
2012
Aspidin PB, a phloroglucinol derivative isolated from Dryopteris fragrans (L.) Schott, has been previously reported to exert high biological activities. In the present study, we analyzed the apoptotic mechanisms of aspidin PB on human hepatoma cell line, HepG2. Initially, aspidin PB was shown to inhibit the growth of HepG2 cells in a time and dose-dependent manner. After treatment with aspidin PB for 72 h, 48 h and 24 h using MTT assay, the IC(50) values were 10.59 μM, 20.86 μM and 46.59 μM, respectively. Aspidin PB was capable to induce apoptosis, as measured by mitochondrial membrane potential (ΔΨm), acridine orange (AO) staining and propidium iodide (PI)/annexin V-FITC double staining. T…
Dryofragin, a phloroglucinol derivative, induces apoptosis in human breast cancer MCF-7 cells through ROS-mediated mitochondrial pathway
2012
Dryofragin is a phloroglucinol derivative extracted from Dryopteris fragrans (L.) Schott. In this study, the anticancer activity of dryofragin on human breast cancer MCF-7 cells was investigated. Dryofragin inhibited the growth of MCF-7 cells in a time and concentration-dependent manner. The cell viability was measured using MTT assay. After treatment with dryofragin for 72, 48 and 24 h, the IC₅₀ values were 27.26, 37.51 and 76.10 μM, respectively. Further analyses of DNA fragmentation and Annexin V-PI double-labeling indicated an induction of apoptosis. Dryofragin-treatment MCF-7 cells had a significantly accumulation of reactive oxygen species (ROS), as well as an increased percentage of …
Microreactor processing for the aqueous Kolbe-Schmitt synthesis of hydroquinone and phloroglucinol
2007
Hydroquinone and phloroglucinol were used as substrates for the aqueous Kolbe-Schmitt synthesis, using a novel processing methodology, termed high-p,T processing, recently demonstrated for the carboxylation of resorcinol. By the high-p,T approach, the temperature limitations of classical batch synthesis, e.g., set by reflux conditions (solvent boiling point), can be overcome by simple technical expenditure, e.g., the use of a few microstructured components, a capillary, and a needle valve at very low internal holdup. In this way, favorable speed-up of chemical reaction is achieved at temperatures normally outside the useful range for organic synthesis. While the hydroquinone synthesis gave …
Hypericum Extract and Hyperforin: Memory-Enhancing Properties in Rodents
2001
Effects of a Hypericum extract in therapeutic use and hyperforin sodium salt were evaluated in rat and mouse avoidance tests. In a conditioned avoidance response (CAR) test on the rat, oral daily administration of hyperforin (1.25 mg/kg/day) or of the extract (50 mg/kg/day) before the training sessions considerably improved learning ability from the second day onwards until the day 7. In addition, the memory of the learned responses acquired during 7 consecutive days of administration and training was largely retained even after 9 days without further treatment or training. The observations made using different doses indicate that these learning-facilitating and/or memory-consolidating effe…
Antidepressant-like activity of hyperforin and changes in BDNF and zinc levels in mice exposed to chronic unpredictable mild stress.
2019
Abstract Chronic unpredictable mild stress (CUMS) - a rodent model of depression mimics a variety of neurochemical and behavioral alterations similar to those seen in human depression. This study evaluated the antidepressant activity of hyperforin in the CUMS model using fluoxetine (FLX) as a reference drug. The antidepressant-like effects of hyperforin and FLX were evaluated in the tail suspension test (TST), forced swim test (FST), and splash test (SPT). CUMS induced an increase in immobility time in mice (pro-depressive effects) in the FST and TST. CUMS-induced changes were reversed by chronic treatment with hyperforin (2.5 and 5 mg/kg), as well as FLX (10 mg/kg). SPT results revealed a …
Dual modulation of striatal acetylcholine release by hyperforin, a constituent of St. John's wort.
2002
Extracts of the medicinal plant St. John's wort (Hypericum perforatum) are widely used for the treatment of mild to moderate depression. Hyperforin, a constituent of St. John's wort, is known to inhibit the sodium-dependent uptake of catecholamines and amino acids into synaptic nerve endings, probably by interference with mechanisms controlling the synaptic sodium concentration. Because de novo synthesis of acetylcholine (ACh) is dependent on sodium-dependent high-affinity choline uptake, we studied the effect of hyperforin on choline (Ch) uptake in vitro and on striatal ACh release in vivo using microdialysis. In rat brain synaptosomes, hyperforin inhibited high-affinity choline uptake wit…