• Journal of Marine Bioscience and Biotechnology
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• v.1 no.2
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• pp.126-135
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• 2006

Phlorotannins which is oligomeric polyphenol of phloroglucinol unit were isolated from solvent fractions of methanolic extract of the brown alga, Ecklonia cava (EC). The inhibitory effects of phlorotannins from EC solvent fractions on oxidative stress were examined in human dermal fibroblasts (HDFs) related to wrinkle formation. Among the solvent fractions, phlorotannins from ethyl acetate fraction exerted the highest scavenging effect on DPPH radical, hydroxyl radical and alkyl radical analyzed by electron spin resonance (ESR) spectroscopy. The levels of intracellular reactive oxygen species (ROS) and lipid peroxidation were measured using 2',7'-dichlorofluorescin diacetate (DCFH-DA) and diphenyl-1-pyrenylphosphine (DPPP), respectively. Their levels were significantly decreased in the presence of phlorotannins from ethyl acetate fraction, compared with other fractions obtained from EC extract (P < 0.01). Furthermore, intracellular glutathione (GSH) level was significantly increased in a time dependent manner by the phlorotannins. Therefore, these results suggest that phlorotannins from EC extract could have a therapeutic potential for prevention and treatment of several diseases such as wrinkle formation related to oxidative stress.

• Microbiology and Biotechnology Letters
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• v.25 no.5
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• pp.459-463
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• 1997

A bacterium DGUM 2011 has been selected from various samples of industrial wastewater and soil. Based on the morphological and physiological characteristics, the isolate DGUM 2011 was identified as Rhodococcus sp. and named as Rhodococcus sp. DGUM 2011. The optimal temperature and pH for the cell growth of Rhodococcus sp. DGUM 2011 were 37$\circ$C and 7.6, respectively. When phenol was added to the minimal media as a sole source of carbon and energy, the concentrations of maximum and optimum for cell growth was 0.10% and 0.08%, respectively. When 0.05% phenol was given in the minimal media, Rhodococcus sp. DGUM 2011 completely utilize it within 24 hrs. The isolate could utilize benzoic acid, p-hydroxybenzoate, p-cresol, tyrosine and phloroglucinol. The isolate possessed both catechol 1,2-dioxygenase and 2,3-dioxygenase activity. However, the activity of catechol 1,2-dioxygenase was much higher than that of 2,3-dioxygenase, which suggests that the isolate might degrade phenol via both ortho- and meta-cleavage, mainly via ortho-cleavage.

• Korean Journal of Pharmacognosy
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• v.49 no.3
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• pp.189-202
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• 2018

Hop cones (Humuli Strobili) are the female inflorescences of hop plants (Humulus lupulus L.) belonging to the family Cannabaceae. They have been used as herbal remedies to treat mood and sleep disturbances, and mainly to add as a bittering ingredient in brewing process. Considerable interests on pharmacological and biological activities of hop cones have been focused on their major constituents, namely, phloroglucinols (humulone, lupulone), terpenes (myrcene, humulene), and prenylated flavonoids (xanthohumol, isoxanthohumol, 6-prenylnaringenin, and 8-prenylnaringenin). The present review describes and discusses biological activity profiles of these major compounds in the hop cones.

• Journal of the Korean Wood Science and Technology
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• v.29 no.3
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• pp.83-91
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• 2001

This paper examines the structural characteristics of fern lignins (deer fern (Blechnum spicant), sword fern (Polystichum munitum) and maidenhair fern (Adiantum pedatum)) by chemical degradation methods of thioacidolysis and nitrobenzene oxidation as well as 13C NMR. Phloroglucinol-HCI staining indicates that the lignins are specifically accumulated at the sclerenchyma cells beneath the epidermis and vascular bundles. The fern lignins consist of only guaiacyl units. Remarkably, the frequency of the -O-4 linkages is extremely low in fern lignins (only 9 to 11 %). Furthermore, the presence of lignin is ambiguous in maidenhair fern, due to very rare amount of -O-4 linkage. Biphenyl (5-5) and 1,2 bis arylpropane (-1) are main condensed dimeric substructures in fern lignins over 70%. In addition, 13C NMR analysis strongly evidenced the integration of phenolics or their derivatives into the fern lignins.

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1225-1231
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• 2013

A novel class of hyperbranched polyesters, HPpEP and HPmEP, were prepared via a facile one-pot polymerization of a phloroglucinol (as a $B_3$ monomer) with a phthaloyl dichloride (as an $A_2$ monomer) for replacing a problematic BPA developer in thermal printing system. The resulting polymers, HPpEP and HPmEP, had highly branched structures and met well the requirements for high performance developer materials such as colorlessness, easy and inexpensive synthesis, high thermal stability, etc. In addition, these polymers exhibited an efficient reaction with leuco dyes (ODB-2) for a coloring process by releasing protons from linear and terminal phenol groups of polymers when heated.

• Journal of the East Asian Society of Dietary Life
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• v.4 no.1
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• pp.79-86
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• 1994

Food quality in food processing and storage were affected by the kinds of phenolics involved. To analyze phenolics of Chebulae Fructus by the way of GC-MSm methylation and trimethylsilyation(TMS) are necessary. The methods of methylation were dimethyl sulfate method and diazomethane method. so this study was undertaken to research the better methylation method before measuring GC-MS. But dimethyl sulfate method of methylation was not sufficient to analyze phenolics. So the phenolics of Chebulae Fructus were analyzed by the diazomethane methylation method and TMS with the pyridine, N-O-bis-trimethylsilyl-acetamide(BSTFA) and trimethylchlorosilane(TMCS). With the exception of pyrogallol and phloroglucinol in insoluble phenolics of Chebulae Fructus, the greater part of phenolics. analysis could be analyzed by GC-MS in company with diazomethane methylation method and TMS.

• Journal of the Korean Applied Science and Technology
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• v.13 no.1
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• pp.47-54
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• 1996

Cinnamoyl ester(PGEFC) of poly(phloroglucinol-formaldehyde) glycidyl ether which has photosensitive functional group was prepared to apply to photoresist. Photosensitivity of PGEFC was estimated by the solubility difference in organic solvent before and after exposure to light. The yield of residual film was calculated by immersing the sample-coated quartz plates in the solvent which was used in coating. The yield of the residual film which was closely related to the sensitivity of the film, was affected by the degree of polymerization of the backbone resin, sensitizers and their concentration. The sensitivity was depended upon the degree of polymerization. Most of effective sensitizer for PGEFC among the sensitizers was 2, 6-dichloro-4-nitroaniline.

• Archives of Pharmacal Research
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• v.12 no.1
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• pp.26-33
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• 1989

Nineteen flavonoids, five phenolics, two coumarins, maltol and L-ascorbic acid were tested as scavenger of nitrite which is believed to participate in the formation of N-nitroso compounds. Many were found to be potent scavenger and the five most potent ones were (+)-catechin, (-)-epicatechin, phloroglucinol, caffeic acid and L-ascorbic acid. The nitrite scavenging effect was higher at pH 1.2 than pH 3.0 and increased when the incubation time was longer. The possible relationship of structures to scavenging effect of the flavonoids tested was discussed.

• Current Research on Agriculture and Life Sciences
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• v.9
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• pp.61-69
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• 1991

Free phenolic acid, esterified and insoluble phenolic acid extract were extracted from Ginkgo nuts and leaves. Antioxidative effectiveness was measured by Peroxide value and TBA value at each extract, control, 0.02%(w/w) BHA and BHT in corn oil, at $45{\pm}1^{\circ}C$ and dark thermo static oven for 45 days. Laboratory tube was added by BHA, BHT, separated free phenolic acids, esterified and insoluble-bound phenolic acid extract of Ginkgo nuts and leaves 127, 95, 140, 121, 280 meq/kg, oil. On the other hand, at the same condition TBA values of each antioxidative matter were 0.430, 0.153, 0.059, 0.175, 0.260, 0.187, 0.160, 0.174, 0.195. This result remarkably appeared antioxidative effectiveness in corn oil substrate, ${\rho}$-Hydroxybenzoic acid, Syringic acid, Gallic acid, Protocatechuic acid, Pyrogallol, Caffeic acid, Coumaric acid, trans-Cinnamic acid, Phloroglucinol.

• Journal of Life Science
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• v.28 no.10
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• pp.1170-1178
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• 2018

The anti-inflammatory effect of brown alga Ecklonia cava is well known, and several phlorotannins have also been reported. In this study, major active components for anti-allergy and anti-inflammation were identified by NMR and MS analysis, and the levels of effectiveness were compared. Six major phlorotannins-phloroglucinol, eckol, eckstolonol, triphlorethol-A, phlorofucofuroeckol A, and dieckol-were isolated from the ethyl acetate fraction of E. cava. In order to analyze the major active substances in E. cava, antioxidant, anti-inflammatory, and anti-allergic effects were evaluated for the six separate substances. Antioxidant capacities of each phlorotannin were evaluated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals, where phlorofucofuroeckol A and triphlorethol-A had the highest radical scavenging capacity in respective radical scavenging assays. Phlorofucofuroeckol A exhibited the highest inhibition of nitric oxide production in LPS-stimulated RAW 264.7 cells among phlorotannins tested. Dieckol inhibited the release of ${\beta}-hexosaminidase$, a marker for the release of histamine in mast cells, in a dose-dependent manner in antigen-stimulated RBL-2H3 mast cells. Additionally, no cytotoxicities were observed at 1 and $2{\mu}g/ml$ in both phlorofucofuroeckol A and dieckol. These results suggest that phlorofucofuroeckol A and dieckol may play a key role in allergic inflammatory reactions.