• Title, Summary, Keyword: phloroglucinol

Search Result 63, Processing Time 0.029 seconds

Structural Investigation of Lignins in Three Different Ferns (Pteridopbytes)

  • Choi, Joon-Weon
    • Journal of the Korean Wood Science and Technology
    • /
    • v.29 no.3
    • /
    • pp.83-91
    • /
    • 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.

  • PDF

Nitrite Scavenging Effect by Flavonoids and Its Structure-Effect Relationship

  • Choi, Jae-Sue;Park, Si-Hyang;Choi, Jin-Ho
    • Archives of Pharmacal Research
    • /
    • v.12 no.1
    • /
    • pp.26-33
    • /
    • 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.

  • PDF

Hypersensitive and Apoptotic Responses of Pepper Fruit Against Xnthomonas axonopodis pv. glycines Infection

  • Chang, Sung-Pae;Kim, Young-Ho
    • Proceedings of the Korean Society of Plant Pathology Conference
    • /
    • /
    • pp.72.1-72
    • /
    • 2003
  • Generally, plants defend themselves against pathogens by structural and biochemical reactions. Defense structures act as physical barriers and inhibit the pathogen from gaining entrance and spreading through the plant. Xanthomonas axonopodis pv glycines, the causal pathogen of bacterial pustule of soybean, causes hypersensitive response (HR). When pepper fruits were inoculated with X. axonopodis pv. glycines, in situ, time-series defense-related structural changes occurred in the inoculated sites. Early responses were programmed cell death (PCD), characterized by condensation and vacuolization of the cytoplasm, condensation of nuclear materials, and fragmentation of the nuclear DNA, which were observed by transmission electron microscopy. Nuclear fragmentation was proven by TUNEL method under confocal laser scanning microscopy and DNA laddering through eletrophoresis. At later stages, plant responses were cell elongation and cell division, forming a periderm-like boundary layer that demarcated healthy tissues from the inoculation sites. Using several stains such as toluidine blue, sudan IV, annexin V, and phloroglucinol-HCl, defense-related materials and structural changes were also examined.

  • PDF

Methylation Methods on Identification of Phenolics in Chebulae Fructus (Chebulae Fructus중 페놀 물질 확인시의 Methylation법 비교)

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

  • PDF

Synthesis and Photocharacteristics of Trihydric Phenol Photoresist (Trihydric Phenol계 Photoresist의 합성과 그 감광 특성)

  • Hong, Eui-Suk;Ko, Jae-Yong;Park, Hong-Soo
    • Journal of the Korean Applied Science and Technology
    • /
    • v.13 no.1
    • /
    • pp.47-54
    • /
    • 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.

Deodorizing, antimicrobial and glucosyltransferase inhibitory activities of polyphenolics from biosource

  • Kim, Yeon;Jang, Su-Ji;Kim, Hyeung-Rak;Kim, Seon-Bong
    • The Korean Journal of Chemical Engineering
    • /
    • v.34 no.5
    • /
    • pp.1400-1404
    • /
    • 2017
  • We evaluated the deodorizing activities of polyphenolics against methyl mercaptan and their inhibitory activity on Streptococcus mutans, Candida albicans, and glucosyltransferase responsible for oral health. Polyphenolics including eckol, dieckol, catechol, catechin, phloroglucinol, chlorogenic acid, epigallocatechin gallate (EGCG), epicatechin gallate (ECG), epigallocatechin (EGC), caffeic acid, and tannic acid were used to investigate their deodorizing, antimicrobial and enzyme activity. Among the polyphenolics, dieckol, eckol, and catechol showed higher deodorizing activity against methyl mercaptan than sodium copper chlorophyllin known as a commercial deodorant. Catechol, dieckol, and eckol exhibited a strong antimicrobial activity on S. mutans, while cinnamic acid, caffeic acid, and catechol showed a strong antifungal activity on C. albicans compared to other polyphenolics. Tannic acid, ECG, and dieckol strongly inhibited the activity of the glucosyltransferase produced by Streptococcus mutans.

Effect of phlorotannins isolated from Ecklonia cava on angiotensin I-converting enzyme (ACE) inhibitory activity

  • Wijesinghe, W.A.J.P.;Ko, Seok-Chun;Jeon, You-Jin
    • Nutrition Research and Practice
    • /
    • v.5 no.2
    • /
    • pp.93-100
    • /
    • 2011
  • Inhibition of angiotensin I-converting enzyme (ACE) activity is the most common mechanism underlying the lowering of blood pressure. In the present study, five organic extracts of a marine brown seaweed Ecklonia cava were prepared by using ethanol, ethyl acetate, chloroform, hexane, and diethyl ether as solvents, which were then tested for their potential ACE inhibitory activities. Ethanol extract showed the strongest ACE inhibitory activity with an $IC_{50}$ value of 0.96 mg/ml. Five kinds of phlorotannins, phloroglucinol, triphlorethol-A, eckol, dieckol, and eckstolonol, were isolated from ethanol extract of E. cava, which exhibited potential ACE inhibition. Dieckol was the most potent ACE inhibitor and was found to be a non-competitive inhibitor against ACE according to Lineweaver-Burk plots. Dieckol had an inducible effect on the production of NO in EAhy926 cells without having cytotoxic effect. The results of this study indicate that E. cava could be a potential source of phlorotalnnins with ACE inhibitory activity for utilization in production of functional foods.

페놀 분해 Rhodococcus sp. DGUM 2011의 분리 및 특성

  • 오정석;한영환
    • Microbiology and Biotechnology Letters
    • /
    • v.25 no.5
    • /
    • pp.459-463
    • /
    • 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.

  • PDF

Hyperbranched Poly(aryl ester)s as Developer Materials for Thermal Printing System

  • Jang, Yeon-Im;Choi, Won-Ho;An, Byeong-Kwan
    • Bulletin of the Korean Chemical Society
    • /
    • v.34 no.4
    • /
    • pp.1225-1231
    • /
    • 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.

Anti-inflammatory and Anti-allergic Effects of Phlorofucofuroeckol A and Dieckol Isolated from Ecklonia cava (감태에서 분리된 플로로탄닌의 염증 및 알러지 억제 효과)

  • Lee, Seung-Su;Bang, Myun-Ho;Jeon, Hyeong-Ju;Hwang, Taekyoo;Yang, Seun-Ah
    • Journal of Life Science
    • /
    • v.28 no.10
    • /
    • pp.1170-1178
    • /
    • 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.