PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “PHLOROGLUCINOL”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5Linked to original sources
PubMed2003

Comparison of the growth-inhibitory effect of Hypericum perforatum L. extracts, differing in the concentration of phloroglucinols and flavonoids, on leukaemia cells.

In this study we compared, simultaneously, the growth-inhibitory effect of Hypericum perforatum L. extracts, containing various amounts of hyperforin (A 3.25%; B 2.21%; C 0.21% w/w) and flavonoids (A and B 5.3%; C 10% w/w), but closely same amounts of naphthodiantrones (0.3%) on two leukaemic cell lines K562 and U937 in the WST-1 assay. The GI50 (concentration of extracts which caused 50% of cell growth inhibition) for H. perforatum extracts analysed and characterized by HPLC for their biologically active constituents was 248.3-621.3 microg mL(-1) in K562 and 378.2-911.7 microg mL(-1) in U937 cells. The corresponding values of the three main groups were 1.6-3.9 microM naphthodianthrones, 1.0-40.7 microM phloroglucinols and 30.5-68.5 microM flavonoids. The results of this study supported the hypothesis that, apart from hyperforin and flavonoids, other components of the extract could be involved in its growth-inhibitory effect that it exerts without light activation.

Antineoplastic Agents, Phytogenic↗
PubMed2003

Antioxidant activity of two phloroglucinol derivatives from Dryopteris crassirhizoma.

The rhizome of Dryopteris crassirhizoma NAKAI exhibited significant antioxidant activity, as assessed by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity in vitro. Two phloroglucinol derivatives, flavaspidic acids PB (1) and AB (2), were isolated from the rhizome of D. crassirhizoma by a bioassay-guided fractionation. 1H-, 13C-NMR, and UV analysis were used to determine the structures. Furthermore, the two compounds were tested for their antioxidant activities, such as their DPPH radical scavenging, superoxide radical scavenging, and lipid peroxidation (LPO) inhibitory activities. Compounds 1 and 2 exhibited potent antioxidant activity against the LPO inhibitory test with IC(50) values of 12.9 and 13.1 microM, respectively, compared with alpha-tocopherol (IC(50); 15.6 microM) and butylated hydroxy anisole (BHA, IC(50); 10.8 microM), while the two compounds had a moderated effect on the DPPH radical scavenging activity (IC(50); 71.7, 76.3 microM) as well as superoxide radical scavenging activity (IC(50); 58.6, 64.4 microM). The potent activity of the flavaspidic acids (1, 2) on inhibiting LPO might be due to possible stabilization as a result of chelating with iron.

Animals↗
PubMed1990

Cytotoxic and antiherpetic activity of phloroglucinol derivatives from Mallotus japonicus (Euphorbiaceae).

The phloroglucinol derivatives isolated from Mallotus japonicus Muell. Arg. (Euphorbiaceae) and their derivatives were evaluated for their capacity to produce cytotoxicity in HeLa cells and to inhibit the replication of herpes simplex virus type 1 (HSV-1). The characterizations of an isolated new acetophenone, mallophenone (16), and cyclization products of mallotojaponin (1), isomallotochromene (17), mallotochroman (18) and isomallotochroman (19), were also described. All tested derivatives inhibited the replication of HSV-1 with ED50 in the range of 88 ng--48 micrograms/ml. The derivatives 12 and 19 were found in vitro therapeutic index with 10.9 and 9.1, respectively, and they were considered to be active antivirals.

Antiviral Agents↗
PubMed2000

Ichthyotoxic phloroglucinol derivatives from Dryopteris fragrans and their anti-tumor promoting activity.

Two new ichthyotoxic compounds, aspidin PB (8) and dryofragin (9), along with three known phloroglucinol derivatives (1-3) and five terpenoids, were isolated from the whole herbs of Dryopteris fragrans by toxicity-directed fractionation using Oryzias latipes (Japanese name; medaka). The structures of the new compounds were determined by spectroscopic methods including 2D NMR techniques. Amongst the isolates, aspidin PB (8), dryofragin (9), and 1-5 exhibited potent ichthyotoxic activity against medaka with a median tolerance limit (TLm after 24 h) of 1.2-4.3 microg/ml. These compounds which are toxic to fish also had a potent inhibitory effect on the activation of Epstein-Barr virus early-antigen (EBV-EA) induced by tetradecanoyl phorbol 13-acetate, which is an in vitro short-term assay for anti-tumor promoting agents. Aspidin BB (2) and albicanol (4), which exhibited strong inhibitory effects on the EBV-EA activation, significantly suppressed an in vivo two-stage carcinogenesis on mouse skin.

Animals↗
PubMed2000

Successful propagation in vitro of apple rootstock MM106 and influence of phloroglucinol.

Successful in vitro propagation of clonal apple rootstock MM106 was achieved by culturing axillary buds on MS basal medium with BAP (1 mg/L), GA3 (0.5 mg/L) and IBA (0.1 mg/L). Use of liquid medium (LM) in initial cultures reduced phenol exudation to a greater extent and gave maximum sprouting percentage when transferred to solid MS medium. Phloroglucinol (PG) did not enhance sprouting of buds but increased the rate of multiplication when added in the medium. Maximum number of shoots were obtained when MS medium was supplemented with BAP (0.5 mg/L), GA3 (1 mg/L), IBA (0.1 mg/L) and PG (100 mg/L). For rooting, in vitro regenerated shoots were placed in IBA (30 mg/L) for 3 hr and transferred to solidified auxin free medium. Rooting was recorded in about 80% of shoots. Inclusion of PG in rooting medium was not beneficial but shoot cultures grown in its presence gave higher rooting percentage. Rooted plantlets showed about 70% survival rate in potting mixture of sand:soil:perlite (1:1:1).

Culture Media↗
PubMed2004

Efficient clonal propagation method for Decalepis hamiltonii, an endangered shrub, under the influence of phloroglucinol.

A highly efficient two stage protocol was developed for induction of multiple shoots from single node in vitro shoot tip explants of Decalepis hamiltonii. It was found that phloroglucinol (PG) had synergistic effect on shoot multiplication when added with N6-benzyladenine and gibberellic acid. This protocol uses PG for both multiple shoot induction from nodal explants, elongation of primary shoots and initiation of adventitious shoot formation from primary shoots, which was more in presence of triacontanol (TRIA). Maximum number of shoots per culture was observed on the medium containing N6-benzyladenine (1.1 microM; BA), GA3 (5.8 microM) and PG (800 microM). Sub-culturing of the shoots onto MS medium containing optimum concentration of BA (5.6 microM), PG (200 microM) and TRIA (0.011 microM) produced elongated shoots along with secondary shoot formation. The long shoots were rooted on alpha-naphthalene acetic acid (5.38 microM; NAA) and PG (400 microM) containing medium. The rooted plantlets were hardened and their field survival rate was 80-90%.

Culture Media↗
PubMed2006

[Studies on phloroglucinol derivatives of Dryopteris fragrans L].

OBJECTIVE: To study the phloroglucinol derivatives of Dryopteris fragrans. METHODS: Isolation and purification were carried out on repeated silica gel, Sephadex LH-20 column chromatography and prepare HPLC. The structures of the compounds were determined by physicochemical properties and spectral analysis. RESULTS: Four compounds were isolated and identified as aspidin PB (I), dryofragin (II), aspidinol (III), aspidin BB (IV). CONCLUSION: Compounds IV is isolated from this plant for the first time.

Chromatography, High Pressure Liquid↗
PubMed1979

A simplified, colorimetric micromethod for xylose in serum or urine, with phloroglucinol.

We have developed a simplified xylose assay procedure that requires only 10 min and requires 50 microL of serum or 5 microL of urine. The reaction with phloroglucinol is more sensitive than the classic p-bromaniline color reaction, and requires only 4 min of heating for color development. A single reagent is mixed with the specimen directly, without prior protein precipitation. Analytical recovery of xylose added to serum was quantitative; precision studies resulted in a between-day coefficient of variation of 5.2%. Glucose, which has significant potential for interference in most other xylose procedures, reacts under the test conditions only to the extent of 70 mumol of apparent xylose per liter for a 5.5 mmol/L solution of glucose. The new procedure has been valuable in the assessment of malabsorption, especially in children and infants, where serum xylose is the preferred measurement.

Carbohydrates↗
PubMed2007

Investigation of the mechanism of action of pyrogallol-phloroglucinol transhydroxylase by using putative intermediates.

Pyrogallol-phloroglucinol transhydroxylase from Pelobacter acidigallici, a molybdopterin-containing enzyme, catalyzes a key reaction in the anaerobic degradation of aromatic compounds. In vitro, the enzymatic reaction requires 1,2,3,5-tetrahydroxybenzene as a cocatalyst and the transhydroxylation occurs without exchange with hydroxy groups from water. To test our previous proposal that the transfer of the hydroxy group occurs via 2,4,6,3',4',5'-hexahydroxydiphenyl ether as an intermediate, we synthesized this compound and investigated its properties. We also describe the synthesis and characterization of 3,4,5,3',4',5'-hexahydroxydiphenyl ether. Both compounds could substitute for the cocatalyst in vitro. This indicates that the diphenyl ethers can intrude into the active site and initiate the catalytic cycle. Recently, the X-ray crystal structure of the transhydroxylase (TH) was published16 and it supports the proposed mechanism of hydroxy-group transfer.

Anaerobiosis↗
PubMed2004

A test for homology: photoactive crystalline assemblies involving linear templates based on a homologous series of phloroglucinols.

[reaction: see text] Cocrystallization of trans-1,2-bis(4-pyridyl)ethylene (4,4'-bpe) with eight members of a homologous series of phloroglucinols 1a-h yields molecular solids 2(1a-h).2(4,4'-bpe) with components held together by four O-H...N hydrogen bonds. In each case, the molecules assemble to form a discrete four-component assembly with olefins preorganized for a [2 + 2] photodimerization. UV irradiation of each member in the series of solids produces rctt-tetrakis(4-pyridyl)cyclobutane (4,4'-tpcb), stereospecifically, in up to 100% yield.

Journal Article↗
PubMed2004

Crystal structure of pyrogallol-phloroglucinol transhydroxylase, an Mo enzyme capable of intermolecular hydroxyl transfer between phenols.

The Mo enzyme transhydroxylase from the anaerobic microorganism Pelobacter acidigallici catalyzes the conversion of pyrogallol to phloroglucinol. Such trihydroxybenzenes and their derivatives represent important building blocks of plant polymers. None of the transferred hydroxyl groups originates from water during transhydroxylation; instead a cosubstrate, such as 1,2,3,5-tetrahydroxybenzene, is used in a reaction without apparent electron transfer. Here, we report on the crystal structure of the enzyme in the reduced Mo(IV) state, which we solved by single anomalous-diffraction technique. It represents the largest structure (1,149 amino acid residues per molecule, 12 independent molecules per unit cell), which has been solved so far by single anomalous-diffraction technique. Tranhydroxylase is a heterodimer, with the active Mo-molybdopterin guanine dinucleotide (MGD)(2) site in the alpha-subunit, and three [4Fe-4S] centers in the beta-subunit. The latter subunit carries a seven-stranded, mainly antiparallel beta-barrel domain. We propose a scheme for the transhydroxylation reaction based on 3D structures of complexes of the enzyme with various polyphenols serving either as substrate or inhibitor.

Bacteria, Anaerobic↗