scholarly journals “The Importance of a Phenolic Group in the Substrates of Iodotyrosine Deiodinase”

2018 ◽  
Vol 32 (S1) ◽  
Author(s):  
Carla Michelle Quinones ◽  
Anton Kozyryev ◽  
Steven Rokita
Keyword(s):  
Iodotyrosine Deiodinase ◽  
Phenolic Group

Studies on the mechanism of acute inhibition of thyroglobulin hydrolysis by iodine

1985 ◽  
Vol 108 (4) ◽  
pp. 511-517 ◽  
Author(s):  
Nandalal Bagchi ◽  
Birdie Shivers ◽  
Thomas R. Brown
Keyword(s):  
Time Course ◽  
Period 2 ◽  
Iodotyrosine Deiodinase ◽  
Rate Of Hydrolysis ◽  
Underlying Mechanisms ◽  
Excess Iodide ◽  
Sites Of Action ◽  
Hydrolysis Of

Abstract. Iodine in excess is known to acutely inhibit thyroidal secretion. In the present study we have characterized the time course of the iodine effect in vitro and investigated the underlying mechanisms. Labelled thyroid glands were cultured in vitro in medium containing mononitrotyrosine, an inhibitor of iodotyrosine deiodinase. The rate of hydrolysis of labelled thyroglobulin was measured as the proportion of labelled iodotyrosines and iodothyronines recovered at the end of culture and was used as an index of thyroidal secretion. Thyrotrophin (TSH) administered in vivo acutely stimulated the rate of thyroglobulin hydrolysis. Addition of Nal to the culture medium acutely inhibited both basal and TSH-stimulated thyroglobulin hydrolysis. The effect of iodide was demonstrable after 2 h, maximal after 6 h and was not reversible upon removal of iodide. Iodide abolished the dibutyryl cAMP induced stimulation of thyroglobulin hydrolysis. Iodide required organic binding of iodine for its effect but new protein or RNA synthesis was not necessary. The inhibitory effects of iodide and lysosomotrophic agents such as NH4C1 and chloroquin on thyroglobulin hydrolysis were additive suggesting different sites of action. Iodide added in vitro altered the distribution of label in prelabelled thyroglobulin in a way that suggested increased coupling in the thyroglobulin molecule. These data indicate that 1) the iodide effect occurs progressively over a 6 h period, 2) continued presence of iodide is not necessary once the inhibition is established, 3) iodide exerts its action primarily at a post cAMP, prelysosomal site and 4) the effect requires organic binding of iodine, but not new RNA or protein synthesis. Our data are consistent with the hypothesis that excess iodide acutely inhibits thyroglobulin hydrolysis by increasing the resistance of thyroglobulin to proteolytic degradation through increased iodination and coupling.

Isolation and characterization of the ethynylestradiol-biodegrading microorganism Fusarium proliferatum strain HNS-1

2002 ◽  
Vol 45 (12) ◽  
pp. 175-179 ◽  
Author(s):  
J.H. Shi ◽  
Y. Suzuki ◽  
B.-D. Lee ◽  
S. Nakai ◽  
M. Hosomi
Keyword(s):  
Culture Medium ◽  
Polar Compounds ◽  
Sole Source ◽  
Order Rate Constant ◽  
Fusarium Proliferatum ◽  
Rrna Gene ◽  
28S Rrna ◽  
Isolation And Characterization ◽  
Phenolic Group

We cultivated hundreds of sediment, soil, and manure samples taken from rivers and farms in a medium containing ethynylestradiol (EE2) as the sole source of carbon, so that microorganisms in the samples would acclimatize to the presence of EE2. Finally, we isolated an EE2-degrading microorganism, designated as strain HNS-1, from a cowshed sample. Based on its partial nucleotide sequence (563 bp) of the 28S rRNA gene, strain HNS-1 was identified as Fusarium proliferatum. Over 15 days, F. proliferatum strain HNS-1 removed 97% of EE2 at an initial concentration of 25 mg.L−1, with a first-order rate constant of 0.6 d−1. Unknown products of EE2 degradation, which may be more polar compounds that have a phenolic group, remained in the culture medium.

scholarly journals Methyl 3-(4-hydroxyphenyl)propionate

IUCrData ◽  
2018 ◽  
Vol 3 (11) ◽  
Author(s):  
Moaz M. Abdou ◽  
Magdalini Matziari ◽  
Paul M. O'Neill ◽  
Eric Amigues ◽  
Ruixue Zhou ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Intermolecular Interactions ◽  
Title Compound ◽  
Phenyl Ring ◽  
Space Group ◽  
Compound C ◽  
Phenolic Group

The title compound, C10H12O3, crystallizes in the orthorhombicP212121space group. The structure contains a phenolic group with the OH being coplanar with the phenyl ring. The structure exhibits significant hydrogen bonding between the O—H group of one molecule and the CO group of an adjacent one. These O—H...O=C interactions form chains of molecules parallel to thebaxis. No π–π or C—H...π intermolecular interactions are observed.

scholarly journals Isolasi dan Identifikasi Senyawa Fenolik dari Kulit Akar Tumbuhan Artocarpus Dadah Miq 63-74

2015 ◽  
Vol 4 (2) ◽  
pp. 205
Author(s):  
Indarto Indarto
Keyword(s):  
Biological Activity ◽  
Phenolic Compounds ◽  
Ir Spectroscopy ◽  
The Other ◽  
Flash Chromatography ◽  
Rare Plant ◽  
Isolation And Purification ◽  
Phenolic Group ◽  
The Village ◽  
Murine Leukemia

Artocarpus plant  dadah  Miq.  is one of the species of Artocarpus of the Moraceae family that belongs to a rare plant in nature. This plant is known as the main source of phenolic derivative compound that is flavone compound  in  or  tri-oxygenated and terisoprenilasi in C-3 position ,  and also known as the main source of phenolic compound derived flavonoids, aryl-benzofuran, stilbenoid and xanthane flavonoida, which have biological activity as promoters antitumor, antibacterial, antifungal, antiimflamatori, antikanker and others. This study aimed to isolate and identify the phenolic compounds contained in plant  A .  dadah obtained from the village of Purwoasri, North Metro District, Metro City, Lampung Province. Research stages include collection and sample preparation and extraction, isolation, and purification of compounds using KCV method, flash chromatography  , KKG, and TLC, while the identification of compounds is performed using ultraviolet-visible (UV-VIS) and infrared (IR) spectroscopy. In the present study, three compounds were isolated, one of which was estimated to be flavonoid compounds based on UV-VIS and IR spectra data which also had high activity against murine leukemia P-388 cells with IC 50  3.1 μg / mL. Based on the IR spectral data for the other two compounds there is a -OH uptake in the region of 3200-3500 cm -1, C = C aromatic uptake in the area of 1600-1400 cm -1 , so it is estimated that both compounds are phenolic group compounds.Tumbuhan Artocarpus dadah Miq.merupakan salah satu spesies Artocarpus dari famili Moraceae yang termasuk tumbuhan langka di alam. Tumbuhan ini dikenal sebagai sumber utama senyawa turunan fenolik yaitu senyawa flavon di atau tri-oksigenasi dan terisoprenilasi pada posisi C-3, dan juga dikenal sebagai sumber utama senyawa fenolik turunan flavonoid, aril-benzofuran, stilbenoid dan santon turunan flavonoida, yang memiliki aktivitas biologi sebagai promotor antitumor, antibakteri, antifungal, antiimflamatori, antikanker dan lain-lain.Penelitian ini bertujuan untuk mengisolasi dan mengidentifikasi senyawa fenolik yang terkandung dalam tumbuhan A. dadah yang diperoleh dari desa Purwoasri, Kecamatan Metro Utara, Kota Metro, Provinsi Lampung.Tahapan penelitian yang dilakukan meliputi pengumpulan dan persiapan sampel kemudian ekstraksi, isolasi, dan pemurnian senyawa menggunakan metode KCV, kromatografi flash, KKG, dan KLT, sedangkan identifikasi senyawa dilakukan menggunakan spektroskopi ultraungu-tampak (UV-VIS) dan inframerah (IR). Pada penelitian ini telah berhasil diisolasi tiga senyawa, yang salah satunya diperkirakan senyawa flavonoid berdasarkan data spektrum UV-VIS dan IR yang juga memiliki aktivitas tinggi terhadap sel murine leukemia P-388 dengan IC50 3,1 μg/mL. Berdasarkan data spektrum IR untuk dua senyawa yang lain terdapat serapan –OH pada daerah 3200-3500 cm-1, serapan C=C aromatik di daerah 1600-1400 cm-1, sehingga diperkirakan kedua senyawa tersebut merupakan senyawa golongan fenolik.

scholarly journals Synthesis and Antioxidant of Some New Pyrazolo[1,5-a]pyrimidine, Pyrazolo[5,1-b]quinazoline and Imidazo[1,2-b]pyrazole Derivatives Incorporating Phenylsulfonyl Moiety

2021 ◽  
Vol 10 (3) ◽  
pp. 2414-2428
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Protective Effects ◽  
Oxidative Hemolysis ◽  
Elemental Analyses ◽  
Phenolic Group ◽  
High Antioxidant Activity ◽  
New Compounds

The synthesis and antioxidant of some new pyrazole analogs were described. It is achieved by the reaction of phenyl-4-(phenylsulfonyl)-1H-pyrazole-3,5-diamine (3) with different bifunctional reagents. The free radical-induced damage and the protective effects of the newly synthesized pyrazoles were studied. These new compounds inhibit the free radical-induced oxidative hemolysis of red blood cells effectively. It was found that these compounds effectively inhibit the free radical-induced oxidative hemolysis of red blood cells. Compound 5, which contain phenolic group, and 17, which bear sulfur, nitrogen atoms, and benzothiazole ring, respectively displayed high antioxidant activity. Analogs 15, 11, 10, and 9 were proved to exhibit antioxidative activity. Structures of new pyrazoles were confirmed by spectroscopic and elemental analyses and have been screened for their antioxidant activity.

scholarly journals Mechanisms of genotoxic effects of hormones

Genetika ◽  
2002 ◽  
Vol 34 (2-3) ◽  
pp. 59-71
Author(s):  
Ninoslav Djelic
Keyword(s):  
Oxidative Stress ◽  
Biological Evolution ◽  
Genotoxic Effects ◽  
Hormonal Stimulation ◽  
Sexual Steroids ◽  
Group Data ◽  
Cell Components ◽  
Phenolic Group ◽  
Endogenous Substances ◽  
Stimulation Of

A concept that compounds commonly present in biological systems lack genotoxic and mutagenic activities is generally in use, hence a low number of endogenous substances have ever been tested to mutagenicity. Epidemiological and experimental analyses indicated, however, that sexual steroids could contribute to initiation and/or continuation of malign diseases. Detailed studies using methods of biochemistry, molecular biology, cytogenetics and other branches, showed that not only epigenetic mechanisms, such as a stimulation of cell proliferation, but also certain hormones, that can express genotoxic effects, such as covalent DNA modification, then chromosomal lesions and chromosomal aberrations, are in the background of malign transformation under activities of hormones. In the case of oestrogens, it was shown that excessive hormonal stimulation led to a metabolic conversion of these hormones to reactive intermediates with formation of reactive oxygenic derivates, so that cells were virtually under conditions of oxidative stress. Individual and tissue susceptibility to occurrence of deterioration of DNA and other cell components generally results from the differences in efficiency of enzymic and non-enzymic mechanisms of resistance against oxidative stress. Besides, steroid thyeroid hormones and catecholamine (dopamine, noradrenaline/norepinephrine and adrenaline) can express genotoxic effects in some test-systems. It is interesting that all above mentioned hormones have a phenolic group. Data on possible genotoxic effects of peptide and protein hormones are very scarce, but based on the available literature it is considered that this group of hormones probably lacks mutagenic activities. The possibility that hormones, as endogenous substances, express mutagenic activities results from the fact that DNA is, regardless of chemical and metabolic stability susceptible, to a certain extent, to changeability compatible with the processes of the biological evolution.

Effect of intramolecular hydrogen bonding on the relative acidities of substituted salicylic acids in benzene solution

1967 ◽  
Vol 45 (14) ◽  
pp. 1699-1706 ◽  
Author(s):  
G. E. Dunn ◽  
Thomas L. Penner
Keyword(s):  
Hydrogen Bonding ◽  
Electronic Effect ◽  
Benzene Solution ◽  
Intramolecular Hydrogen Bonding ◽  
Acid Strength ◽  
Carboxyl Group ◽  
Hammett Equation ◽  
Phenolic Group ◽  
Intramolecular Hydrogen ◽  
Salicylic Acids

The relative acidities of fifteen 4- and 5-substituted salicylic acids were determined in benzene solution by potentiometric titration. The potentials at half neutralization (h.n.p.) relative to that of salicylic acid were considered to measure the acidities of the substituted acids relative to the parent acid. These potentials, designated by Δhnp, gave a significantly better correlation with Hammett's sigma constants in an equation of the form proposed by Jaffe, Δhnp = ρ1σ1 + ρ2σ2, than in a simple Hammett equation, Δhnp = ρ1σ1. In these equations the subscripts 1 and 2 refer to the position of a substituent relative to the carboxyl group and to the phenolic group respectively. The value of ρ2/ρ1 was found to be 0.4, indicating that the electronic effect of a substituent on the acid strength via the phenolic hydrogen-bonded path is almost half as large as the direct effect through the carboxyl group. These results, together with the fact that in aqueous solution there is very little if any transmission via the phenolic group, are discussed in terms of intramolecular hydrogen bonding of salicylic acids in benzene and in water.

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