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1. Weathering Sequence of Clay-size Minerals in Soils and Sediments

Author:
M. L. Jackson; Y. Hseung; R. B. Corey; E. J. Evans; R. C. Vanden Heuvel
Source:
Soil Science Society of America journal 1952 v.16 no.1 pp. 3-6
ISSN:
0361-5995
Subject:
X-ray diffraction; clay; gibbsite; hematite; hydroxylation; illite; kaolinite; mica; protons; sediments; soil; vermiculite; weathering; China
Abstract:
... Studies were made of several clays of soils and other deposits to clarify the nature of weathering of layer silicates. Data obtained by X-ray diffraction, thermal, R(OH)n sorption, and elemental analyses lead to the proposal of general occurrence of interstratified X-amorphous zones in 2:1 layer silicates. As weathering of true micas proceeds through illite, intermediates, vermiculite, and montmor ...
DOI:
10.2136/sssaj1952.03615995001600010002x

2. Colorimetric Determination of Iron of Mixed Valency by Orthophenanthroline

Author:
G. S. R. Krishna Murti; V. V. Volk; M. L. Jackson
Source:
Soil Science Society of America journal 1966 v.30 no.5 pp. 663-664
ISSN:
0361-5995
Subject:
citrates; color; colorimetry; hydroxylamine; hydroxylation; iron; pH; sodium acetate
Abstract:
... A colorimetric method for the determination of Fe in a mixed Fe³⁺ and Fe²⁺ valency system has been proposed. Complete reduction of Fe³⁺ to Fe²⁺, which was essential for the formation of a stable colored complex with orthophenanthroline, was obtained when the iron solution, buffered at pH 3.5 with sodium acetate, was heated for 1 hr at 65C with 5% hydroxylamine hydrochloride. This reduction procedu ...
DOI:
10.2136/sssaj1966.03615995003000050037x

3. Heats of Immersion Studies on Anion-Treated Ferric Oxide

Author:
J. J. Jurinak; R. G. Burau
Source:
Soil Science Society of America journal 1967 v.31 no.6 pp. 732-736
ISSN:
0361-5995
Subject:
adsorption; anions; calorimetry; energy; heat; hematite; hydroxylation; molybdates; pH; rehydration; sulfates; temperature
Abstract:
... Microcalorimetry was used to obtain heats of immersion data for αFe₂O₃ (hematite) treated with SO₄⁻², H₂PO₄⁻¹ or MoO₄⁻² at pH 4.0. The data were compared with values from a reference OH saturated iron oxide. Using water adsorption data, the net integral heats of adsorption as functions of outgassing temperature (25 to 470C) were calculated. The energies of adhesion were also determined. Anion pene ...
DOI:
10.2136/sssaj1967.03615995003100060011x

4. An Investigation of the Preparation and Reactions of trans-3, 4-Dihydroxycyclohexyl Carbinol as a Cellulose Model Compound

Author:
John J. Porter; Philip A. Spanninger
Source:
Textile research journal v.39 no.7 pp. 638-647
ISSN:
1746-7748
Subject:
acetic anhydride; boiling; boiling point; cellulose; esterification; fabrics; formic acid; gas chromatography; hydroxylation; melting point; models; oxidation; stereochemistry; textile fibers
Abstract:
... The synthesis of the fully equatorial form of trans-3,4-dihydroxycyclohexyl carbinol was achieved and proof of its configuration is presented. The equatorial epimer was prepared from 3-cyclohexcne-1-carboxaldehyde which was oxidized to 3-cyclohexene-11-carboxylic acid, hydroxylated and esterified to give methyl trans-3,4-dihydroxycyclohexyl-1-carboxylate. This compound was converted to the fully e ...
DOI:
10.1177/004051756903900706

5. Thermodynamics of Copper(II)—Calcium Exchange on Bentonite Clay

Author:
M. H. El-Sayed; R. G. Burau; K. L. Babcock
Source:
Soil Science Society of America journal 1970 v.34 no.3 pp. 397-400
ISSN:
0361-5995
Subject:
Gibbs free energy; bentonite; calcium; clay; copper; enthalpy; entropy; hydroxylation; ions
Abstract:
... Thermodynamic parameters were derived for the exchange reaction between Cu(II) and calcium on bentonite clay in systems essentially devoid of precipitation, hydroxylation, and complex formation. Although the exchange isotherms showed preference of clay for calcium this proved to be only apparent since a large component of the standard free energy change for copper adsorption was due to entropy los ...
DOI:
10.2136/sssaj1970.03615995003400030016x

6. Synthesis and biological activity of 5β-hydroxy analogs of α-ecdysone

Author:
Thompson, M.J.; Robbins, W.E.; Cohen, C.F.; Kaplanis, J.N.; Dutky, S.R.; Hutchins, R.F.N.
Source:
Steroids 1971 v.17 no.1-5 pp. 399-409
Subject:
ecdysone; hydroxylation; chemical structure; spectral analysis; bioactive properties; Musca domestica; Tribolium confusum; Aedes aegypti; Blattella germanica; insect development; metamorphosis; insect reproduction
Abstract:
... Two 5β-hydroxy analogs of α-ecdysone -- 2β,3β,5β,14α-tetrahydroxy-5β-cholest-7-en-6-one and 3β,5β,14α-trihydroxy-5β-cholest-7-en-6-one were synthesized and their mass spectra obtained. The biological activity of these two compounds was compared with that of the most active synthetic ecdysone analog previously tested in insects, and the presence of the 5β-hydroxyl group generally enhanced the inhib ...
Handle:
10113/2440
DOI:
10.1016/S0039-128X(71)80143-5

7. The metabolism of 4-14 C-22, 25-bisdeoxyecdysone during larval development in the tobacco hornworm, Manduca sexta (L.)

Author:
Kaplanis, J.N.; Thompson, M.J.; Dutky, S.R.; Robbins, W.E.; Lindquist, E.L.
Source:
Steroids 1972 v.20 no.1 pp. 105-120
Subject:
Manduca sexta; larvae; insect development; ecdysone; hydroxylation; biochemical pathways; chemical structure; spectral analysis
Abstract:
... Hydroxylation and conjugation were the principal routes of metabolism for 4-14C-22,25-bisdeoxyecdysone when fed to tobacco hornworms during larval development. The major metabolite of 4-14C-22,25-bisdeoxyecdysone isolated from frass and also detected in prepupae was the tetrahydroxy steroid 22-deoxyecdysone. In addition, three 4-14C-pentahydroxy analogs -- 22-deoxyinokosterone, 22-deoxy-26-hydroxy ...
Handle:
10113/2438
DOI:
10.1016/0039-128X(72)90122-5
PubMed:
5042697

8. Influence of pH on the Sorption of Co2+, Zn2+ and Ca2+ by a Hydrous Manganese Oxide

Author:
P. Loganathan; R. G. Burau; D. W. Fuerstenau
Source:
Soil Science Society of America journal 1977 v.41 no.1 pp. 57-62
ISSN:
0361-5995
Subject:
adsorption; calcium; cations; cobalt; hydroxides; hydroxylation; manganese; manganese dioxide; manganese monoxide; metal ions; pH; salt concentration; sodium; thermodynamics; zinc
Abstract:
... The uptake of Co²⁺, Zn²⁺, and Ca²⁺ by δ-MnO₂ at 24.0 ± 0.5°C as a function of pH and salt concentration was investigated. At pH values < 5, δ-MnO₂ released structural Mn to solution phase during the sorption of Co²⁺ and to a lesser extent during Zn²⁺ sorption. Calcium sorption did not release any Mn to solution phase. In addition Co²⁺, Zn²⁺, and Ca²⁺ were shown to adsorb specifically at the δ-MnO₂ ...
DOI:
10.2136/sssaj1977.03615995004100010020x

9. Azetidine-2-carboxylic acid and lily pollen tube elongation

Author:
Dashek, W.V.; Mills, R.R.
Source:
Annals of botany 1980 v.45 no.1 pp. 1-12
ISSN:
0305-7364
Subject:
arabinose; autoradiography; carbon; cell growth; cell walls; cytoplasm; gel chromatography; glycopeptides; glycosylation; hydroxylation; hydroxyproline; leucine; light microscopes; pollen; pollen tubes; proline; silver
Abstract:
... Azetidine-2-carboxylic acid (AZC), which occurs naturally in Liliaceous plants, is reported to be a proline (pro) analogue Plant cell walls contain ‘extensin’, which is rich in hydroxyproline (hyp). Peptidyl hyp arises through hydroxylation of peptidyl pro followed by glycosylation (arabinose attachment) of hyp Because AZC replaces peptidyl prolyl residues, it may be a useful tool for evaluating t ...
DOI:
10.1093/oxfordjournals.aob.a085792

10. Production of Melanin Precursors By A Mutant of Tetrahymena Thermophila*: MELANIN PRECURSORS IN TETRAHYMENA

Author:
ANTHONY R. KANEY; GLEN W. KNOX
Source:
journal of eukaryotic microbiology 1980 v.27 no.3 pp. 339-341
ISSN:
1066-5234
Subject:
Tetrahymena thermophila; catecholamines; culture media; decarboxylation; excretion; hydroxylation; melanin; mutants; oxidation; polymerization; swine; tyramine; tyrosine
Abstract:
... SYNOPSIS. A mutant of Tetrahymena thermophila. “pig,” excretes melanin precursors into the culture medium where spontaneous polymerization to melanin occurs. the precursors, probably oxidation products of catecholamines. are produced in large amounts by the mutant by decarboxylation of tyrosine and hydroxylation of the resulting tyramine. Overproduction and excretion of precursors by the mutan ...
DOI:
10.1111/j.1550-7408.1980.tb04274.x

11. Degradation of atrazine by Pseudomonas: N-dealkylation and dehalogenation of atrazine and its metabolites

Author:
Behki, R.M.; Khan, S.U.
Source:
Journal of agricultural and food chemistry 1986 v.34 no.4 pp. 746-749
ISSN:
0021-8561
Subject:
Zea mays; atrazine; Pseudomonas; biodegradation; soil treatment; soil bacteria; weed control; hydroxylation
DOI:
10.1021/jf00070a039

12. Identification of the isomeric hydroxylated metabolites of methyl 2-[4-(2,4-dichlorophenoxy)phenoxy]propanoate (Diclofop-methyl) in wheat

Author:
Tanaka, F.S.; Hoffer, B.L.; Shimabukuro, R.H.; Wien, R.G.; Walsh, W.C.
Source:
Journal of agricultural and food chemistry 1990 v.38 no.2 pp. 559-565
ISSN:
0021-8561
Subject:
isomers; metabolites; metabolic detoxification; Triticum; hydroxylation; phenoxypropionic herbicides
Abstract:
... The major metabolic pathway for detoxication of diclofop-methyl in tolerant plant species is by ring hydroxylation followed by glucoside conjugation. This investigation reports on the conclusive identification of the three isomeric hydroxylated metabolites of diclofop-methyl obtained from wheat after acid hydrolysis of the glucoside conjugates. Identified as metabolites were the 2,3-dichloro-4-hyd ...
DOI:
10.1021/jf00092a049

13. Synthesis of the enantiomers of 6-epicastanospermine and 1,6-diepicastanospermine from D- and L-gulbnolactone

Author:
Fleet, George W.J.; Ramsden, Nigel G.; Nash, Robert J.; Fellows, Linda F.; Jacob, Gary S.; Molyneux, Russell J.; Cenci di Bello, Isabelle; Winchester, Bryan
Source:
Carbohydrate research 1990 v.205 pp. 269-282
Subject:
dietary carbohydrate; alkaloids; antinutritional factors; plant extracts; hydroxylation; lactones; enantiomers; crystal structure; enzyme inhibitors; glycosidases; glycosidic linkages
Abstract:
... The synthesis of the enantiomers of 6-epicastanospermine and of 1,6-diepicastanospermine from the enantiomeric gulonolactones is reported and the structure of the former is established as (1S,6R,7R,8R,8aR)-1,6,7,8-tetrahydroxyoctahydroindolizine. The inhibitory activities of the diastereomers against the amyloglucosidase-catalysed hydrolysis ofp-nitrophenyl α-d-glucopyranoside were investigated, a ...
Handle:
10113/36376
DOI:
10.1016/0008-6215(90)80146-T

14. A novel compound, 7,10-dihydroxy-8-(E)-octadecenoic acid from oleic acid by bioconversion

Author:
Hou, C.T.; Bagby, M.O.; Plattner, R.D.; Koritala, S.
Source:
Journal of the American Oil Chemists' Society 1991 v.68 no.2 pp. 99-101
ISSN:
0003-021X
Subject:
microbial activity; hydroxylation; oleic acid; bacteria; Illinois
Abstract:
... Sixty-two cultures from the Agricultural Research Service (ARS) Culture Collection and 10 cultures isolated from soil and water samples in Illinois were screened for their ability to convert agricultural oils to value-added industrial chemicals. A new compound, 7,10-dihydroxy-8(E)-octadecenoic acid (DOD), was produced from oleic acid at a yield of greater than 60% by bacterial strain PR3 which was ...
DOI:
10.1007/BF02662326

15. 10-Hydroxy-8(Z)-octadecenoic acid, an intermediate in the bioconversion of oleic acid to 7,10-dihydroxy-8(E)-octadecenoic acid

Author:
Hou, C.T.; Bagby, M.O.
Source:
Journal of industrial microbiology 1992 v.9 no.2 pp. 103-107
ISSN:
0169-4146
Subject:
Pseudomonas; hydroxy fatty acids; pH; hydroxylation; temperature; oleic acid
Abstract:
... Previously, we reported the discovery of a new compound, 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) which was produced from oleic acid by a new bacterial isolate PR3 [6,7]. The reaction is unique in that it involves a hydroxylation at two positions and a rearrangement of the double bond of the substrate molecule. Now, we have isolated another compound from the reaction mixture determined by GC/MS ...
Handle:
10113/24912
DOI:
10.1007/BF01569740

16. Cadmium Sorption to Soil Separates Containing Layer Silicates and Iron and Aluminum Oxides

Author:
John M. Zachara; Steve C. Smith; Charles T. Resch; Christina E. Cowan
Source:
Soil Science Society of America journal 1992 v.56 no.4 pp. 1074-1084
ISSN:
0361-5995
Subject:
Ultisols; aluminum; aluminum oxide; cadmium; cation exchange capacity; electrolytes; hydroxylation; ion exchange; ionic strength; iron; iron oxides; kaolinite; pH; silicates; smectite; sodium perchlorate; soil horizons; soil separates; sorbents; sorption
Abstract:
... Ion exchange to fixed charge sites and surface complexation to hydroxylated sites are recognized to affect Cd aqueous concentrations in soil; however, the individual contribution of these reactions to Cd sorption in mineralogically complex material has not been documented. The objective of this study was to isolate the contributions of fixed charge and hydroxylated sites to Cd sorption in two Ulti ...
DOI:
10.2136/sssaj1992.03615995005600040012x

17. Colorimetric determination of the molar substitution of 2-hydroxybutyl and related starch ethers

Author:
Harry-O'Kuru, R.E.; Moser, K.B.; Gordon, S.H.
Source:
Carbohydrate polymers 1992 v.17 no.4 pp. 313-318
ISSN:
0144-8617
Subject:
corn starch; ethers; spectral analysis; hydroxylation; calorimetry
Abstract:
... The molar substitution (MS) of 2-hydroxyalkyl starch ethers, e.g. 2-hydroxybutyl starch, can be determined spectrophotometrically. The principle involves a dehydrative-hydrolytic generation of n-butyraldehyde from the 2-hydroxybutyl starch ether substituent in concentrated sulfuric acid. The resultant hydrolyzate containing the aldehyde and allylic species of the substituent is complexed with 2,2- ...
Handle:
10113/24924

18. Microbial conversion of linoleic and linolenic acids to unsaturated hydroxy fatty acids

Author:
Koritala, S.; Bagby, M.O.
Source:
Journal of the American Oil Chemists' Society 1992 v.69 no.6 pp. 575-578
ISSN:
0003-021X
Subject:
linoleic acid; fermentation; linolenic acid; hydroxy fatty acids; Nocardia; pH; hydroxylation; temperature; microbial activity
Abstract:
... The conversion of oleic acid to 10-hydroxystearic acid with resting cells of Nocardia cholesterolicum (NRRL 5767) has been previously reported. These same microorganisms also convert linoleic and linolenic acids to 10-hydroxy-12 c-octadecenoic and 10-hydroxy-12 c,15 c-octadecadienoic acids, respectively. The reaction occurs best at 35°C and a pH of 6.5. Under optimum conditions, 75-80% of the unsa ...
Handle:
10113/27609
DOI:
10.1007/BF02636111

19. Production of 15-, 16- and 17-hydroxy-9-octadecenoic acids by bioconversion of oleic acid with Bacillus pumilus

Author:
Lanser, A.C.; Plattner, R.D.; Bagby, M.O.
Source:
Journal of the American Oil Chemists' Society 1992 v.69 no.4 pp. 363-366
ISSN:
0003-021X
Subject:
Bacillus megaterium; hydroxy fatty acids; biological production; hydroxylation; oleic acid; Bacillus pumilus
Abstract:
... Several Bacillus strains were tested for their ability to hydroxylate oleic acid. Two strains-BD-174 and BD-226-converted oleic acid into a trio of hydroxy-octadecenoic acids. Bioconversion in 72-120 hr produced 5-11% of hydroxy acids relative to oleic acid as measured by gas chromatography. These acids were identified as the 15-, 16- and 17-hydroxy-9-octadecenoic acids by gas chromatography-mass ...
Handle:
10113/24454
DOI:
10.1007/BF02636069

20. Production of Fenton's reagent by cellobiose oxidase from cellulolytic cultures of Phanerochaete chrysosporium

Author:
Kremer, S.M.; Wood, P.M.
Source:
European journal of biochemistry 1992 v.208 no.3 pp. 807-814
ISSN:
0014-2956
Subject:
iron; cellobiose; electron transfer; cellulose; oxidoreductases; cellulolytic microorganisms; hydroxylation; Phanerochaete chrysosporium; oxygen
Abstract:
... The reduction of dioxygen by cellobiose oxidase leads to accumulation of H2O2, with either cellobiose or microcrystalline cellulose as electron donor. Cellobiose oxidase will also reduce many FE(III) complexes, including FE(III) acetate. Many FE(II) complexes react with H2O2 to produce hydroxyl radicals or a similarly reactive species in the Fenton reaction as shown: H2O2 + Fe2+ leads to HO(.) + H ...
DOI:
10.1111/j.1432-1033.1992.tb17251.x
PubMed:
1396686

21. Occurrence of hydroxylated jasmonic acids in leaflets of Solanum demissum plants grown under long‐ and short‐day conditions

Author:
Hans Helder; Otto Miersch; Dick Vreugdenhil; Günther Sembdner
Source:
Physiologia plantarum 1993 v.88 no.4 pp. 647-653
ISSN:
0031-9317
Subject:
biosynthesis; linoleate 13S-lipoxygenase; explants; tubers; photoperiod; hydroxylation; roots; Solanum demissum
Abstract:
... Under short‐day (SD) conditions both 11‐OH‐jasmonic acid (11‐OH‐JA) and a smaller quantity of 12‐OH‐JA occurred in leaflets of Solanum demissum Lindl. Plants which had formed tubers. This is the first time that 11‐OH‐JA has been detected as a native substance in higher plants. Under long‐day (LD) conditions no tubers were formed and none of these compounds were detectable. A positive correlation w ...
DOI:
10.1111/j.1399-3054.1993.tb01384.x

22. Simple synthesis of pyrethoid metabolites

Author:
Zhang, M.; Scott, J.G.
Source:
Journal of agricultural and food chemistry 1994 v.42 no.8 pp. 1779-1782
ISSN:
0021-8561
Subject:
lead; pyrethrins; hydroxylation; synthesis; metabolites
Abstract:
... The primary metabolism of 3-phenoybenzyl pyrethroids by microsomal P450 monooxygenases commonly results in hydroxylation at the 2'- or 4'-positions. This paper reports the synthesis of these types of metabolites directly from five pyrethroids: deltamethrin, permethrin, fenvalerate, acrinathrin, and bifenthrin. The reactions were electrophilic substitutions using organometallic reagents. When these ...
DOI:
10.1021/jf00044a039

23. Study of biphenyl hydroxylase activity in Aspergillus parasiticus using a colorimetric assay

Author:
Mobley, D.P.
Source:
Applied microbiology and biotechnology 1994 v.40 no.5 pp. 622-628
ISSN:
0175-7598
Subject:
biphenyl; Aspergillus parasiticus; colorimetry; hydroxylation; enzyme activity; oxygenases
Abstract:
... A colorimetric assay, based on the hydroxylation of 4-nitrobiphenyl (NBP), allows for the first time the quick measurement of the biphenyl hydroxylase activity of whole liquid cultures of Aspergillus parasiticus. The assay can be used to measure the activity in whole cultures containing biphenyl hydroxylase substrates other than NBP. The assay was used to investigate the magnitude and time depende ...
DOI:
10.1007/BF00173318

24. A cytochrome P-450 monooxygenase catalyzes the first step in the conversion of tabersonine to vindoline in Catharanthus roseus

Author:
St-Pierre, B.; De Luca, V.
Source:
Plant physiology 1995 v.109 no.1 pp. 131-139
ISSN:
0032-0889
Subject:
Catharanthus roseus; indole alkaloids; bioassays; enzymology; biosynthesis; biochemical pathways; seedlings; cell suspension culture; oxygenases; oxygen; enzyme inhibitors; leaves; endoplasmic reticulum; methylation; light; plant development; cytochrome P-450; hydroxylation; NADP (coenzyme)
Abstract:
... Hydroxylation at the C-16 position of the indole alkaloid tabersonine has been suggested as the first step toward vindoline biosynthesis in Catharanthus roseus. Tabersonine 16-hydroxylase (16-OH) activity was detected in total protein extracts from young leaves of C. roseus using a novel coupled assay system. Enzyme activity was dependent on NADPH and molecular oxygen and was inhibited by CO, clot ...

25. Comparative metabolism of R(-)-fenoprofen in rats and sheep

Author:
Soraci, A.; Benoit, E.; Delatour, P.
Source:
Journal of veterinary pharmacology and therapeutics 1995 v.18 no.3 pp. 167-171
ISSN:
0140-7783
Subject:
interspecific variation; enantiomers; sheep; nonsteroidal anti-inflammatory agents; biochemical pathways; microsomes; rats; pharmacokinetics; hydroxylation
DOI:
10.1111/j.1365-2885.1995.tb00574.x
PubMed:
7674451

26. Dietary fish oil and cytochrome P-450 monooxygenase activity in rat liver and kidney

Author:
Valdes, E.; Vega, P.; Avalos, N.; Orellana, M.
Source:
Lipids 1995 v.30 no.10 pp. 955-958
ISSN:
0024-4201
Subject:
dodecanoic acid; liver; dietary fat; docosahexaenoic acid; eicosapentaenoic acid; lipid metabolism; microsomes; cytochrome P-450; fish oils; kidneys; rats; enzyme activity; oxygenases; hydroxylation
DOI:
10.1007/BF02537488
PubMed:
8538384

27. Formation of polyhydroxylated isoflavones from the soybean seed isoflavones daidzein and glycitein by bacteria isolated from tempe

Author:
Klus, K.; Barz, W.
Source:
Archives of microbiology 1995 v.164 no.6 pp. 428-434
ISSN:
0302-8933
Subject:
Micrococcus; soybeans; tempeh; daidzein; hydroxylation; Arthrobacter
Abstract:
... Five tempe-derived bacterial strains identified as Micrococcus or Arthrobacter species were shown to transform the soybean isoflavones daidzein and glycitein to polyhydroxylated isoflavones by different hydroxylation reactions. All strains converted glycitein and daidzein to 6,7,4'-trihydroxyisoflavone (factor 2) and the latter substrate also to 7,8,4'-trihydroxyisoflavone. Three strains transform ...
DOI:
10.1007/BF02529741
PubMed:
8588745

28. Modification of plant lipid synthesis

Author:
Topfer, R.; Martini, N.; Schell, J.
Source:
Science 1995 v.268 no.5211 pp. 681-686
ISSN:
0036-8075
Subject:
plant fats and oils; transgenic plants; genetic engineering; fatty acids; biosynthesis; chemical constituents of plants; hydroxylation
Abstract:
... Genetic engineering of new storage oils and fats has produced oil crop plants with fatty acid compositions unattainable by plant breeding alone. The combination of classical breeding methods with molecular techniques provides new ways for designing oils for food and nonfood uses. Alterations in the position and number of double bonds, variation in fatty acid chain length, and the introduction of d ...
DOI:
10.1126/science.268.5211.681
PubMed:
17832379

29. Origin of hydroxyphytoene derivatives formed in the presence of bleaching herbicides

Author:
Albrecht, M.; Sandmann, G.
Source:
Journal of agricultural and food chemistry 1995 v.43 no.6 pp. 1701-1704
ISSN:
0021-8561
Subject:
photolysis; Scenedesmus; carotenoids; hydroxylation; Lepidium sativum; photooxidation; light; flurtamone
Abstract:
... Algae and higher plants treated with the bleaching herbicide fluatamone accumulate not only phytoene but also several derivatives that have phytoene-like spectra. The formation of different hydioxyphytoenes was light-dependent and increased with light intensity. Hydroxylation of phytoene and phytoene epoxide could also be detected in solution with chlorophyll as photosensitizer. With hydroxy-1,2-e ...
DOI:
10.1021/jf00054a054

30. 1,2,3-Trichlorobenzene transformation by Methylosinus trichosporium OB3b expressing soluble methane monooxygenase

Author:
Sullivan, J.P.; Chase, H.A.
Source:
Applied microbiology and biotechnology 1996 v.45 no.3 pp. 427-433
ISSN:
0175-7598
Subject:
Methylosinus trichosporium; gas chromatography; hydroxylation; mass spectrometry; methane; methanotrophs; oxygen; oxygen consumption; sodium formate; washing
Abstract:
... Transformation of 1,2,3- and 1,2,4-trichlorobenzene in the presence of 20 mM sodium formate, by the methanotrophic bacterium Methylosinus trichosporium OB3b, was studied using cells grown in batch and continuous culture. Only 1,2,3-trichlorobenzene was transformed and transformation was strictly co-metabolic, only catalysed in the presence of the soluble form of methane monooxygenase. The kinetics ...
DOI:
10.1007/s002530050708

31. Cannabis 25, biotransformation of cannabidiol and cannabidiolic acid by Pinellia ternata tissue segments

Author:
Tanaka, H.; Takahashi, R.; Morimoto, S.; Shoyama, Y.
Source:
Plant cell reports 1996 v.15 no.11 pp. 819-823
ISSN:
0721-7714
Subject:
metabolism; quantitative analysis; Pinellia ternata; drugs; tubers; culture filtrates; spectral analysis; hydroxylation; cannabidiol; synthesis; chemical structure; metabolites; tissue culture
Abstract:
... Two marihuana constituents, cannabidiol (1) and cannabidiolic acid (4) were each converted mainly to two metabolites using tissue segments of Pinellia ternata tuber. The structures of the metabolites formed from 1 were determined to be 1-O-beta-D-glucopyranoside and 1-O- beta-D-diglucopyranoside by 1H nmr, 13C nmr and fabms. Those from 4 were determined as 4-O-beta-D-glucopyranoside and 10'-hydrox ...
DOI:
10.1007/BF00233147

32. Metabolism of pyriproxyfen. 3. In vitro metabolism in rats and mice

Author:
Yoshino, H.; Kaneko, H.; Nakatsuka, I.; Yamada, H.
Source:
Journal of agricultural and food chemistry 1996 v.44 no.6 pp. 1578-1581
ISSN:
0021-8561
Subject:
pyriproxyfen; metabolism; animal tissues; kidneys; liver; lungs; small intestine; microsomes; cytochrome P-450; oxidation; kinetics; gender differences; rats; mice; hydroxylation
Abstract:
... In vitro metabolism of pyriproxyfen [4-phenoxyphenyl (RS)-2-(2-pyridyloxy)propyl ether, Sumilarv] by several tissues of rats and mice was investigated. Most of the major metabolites of pyriproxyfen observed in studies of in vivo metabolism were formed by liver microsomes incubated in vitro with beta-NADPH for both species. No sex-related differences were observed in mouse microsomes in major in vi ...
DOI:
10.1021/jf950510q

33. A para-site-specific hydroxylation of aromatic compounds by Mycobacterium sp. strain 12523: stabilization of the hydroxylation activity

Author:
Semba, H.; Sakano, K.
Source:
Applied microbiology and biotechnology 1997 v.48 no.2 pp. 256-260
ISSN:
0175-7598
Subject:
Mycobacterium; acetone; hydroxylation; phenols
Abstract:
... Myobacterium sp. strain 12523 has a parasite-specific hydroxylation activity, which produce parasubstituted phenols from various aromatic compounds. However, the activity is unstable and the reactions are inactivated within 24 h. In order to extend the reaction period, the factors that affected reaction stability were examined. The hydroxylation activity of the cells incubated in buffer was signif ...
DOI:
10.1007/s002530051047
PubMed:
9299785

34. Anaerobic metabolism of aromatic compounds

Author:
Heider, J.; Fuchs, G.
Source:
European journal of biochemistry 1997 v.243 no.3 pp. 577-596
ISSN:
0014-2956
Subject:
acetyl coenzyme A; activation energy; adenosine diphosphate; adenosine triphosphate; amino acids; anaerobiosis; bacteria; beta oxidation; biopolymers; carbon dioxide; catechol; electron transfer; flavonoids; hydrolysis; hydroxylation; lignin; melanin; nitrogenase; oxygen; quinones; resorcinol
Abstract:
... Aromatic compounds comprise a wide variety of low-molecular-mass natural compounds (amino acids, quinones, flavonoids, etc.) and biopolymers (lignin, melanin). They are almost exclusively degraded by microorganisms. Aerobic aromatic metabolism is characterised by the extensive use of molecular oxygen. Monoxygenases and dioxygenases are essential for the hydroxylation and cleavage of aromatic ring ...
DOI:
10.1111/j.1432-1033.1997.00577.x
PubMed:
9057820

35. Biotransformation of linoleic acid with the Candida tropicalis M25 mutant

Author:
Fabritius, D.; Schafer, H.J.; Steinbuchel, A.
Source:
Applied microbiology and biotechnology 1997 v.48 no.1 pp. 83-87
ISSN:
0175-7598
Subject:
Candida tropicalis; biotransformation; fermentation; hydroxylation; linoleic acid; mutants; palmitic acid; spectroscopy
Abstract:
... Linoleic acid was transformed by mutant Candida tropicalis M25 and transformations were studied in batch and fed-batch cultures. Cofermentations with palmitic acid as inducer of the fatty acid degradation pathway were performed. Besides the (Z),(Z)-octadeca-6,9-dienedioic acid. (Z),(Z)-3-hydroxyoctadeca-9, 12-dienedioic acid and (Z),(Z)-3-hydroxytetradeca- 5,8-dienedioic acid were obtained as the ...
DOI:
10.1007/s002530051019
PubMed:
9274051

36. Degradation pathway of quinolines in a biofilm system under denitrifying conditions

Author:
Johansen, S.S.; Arvin, E.; Mosbaek, H.; Hansen, A.B.
Source:
Environmental toxicology and chemistry 1997 v.16 no.9 pp. 1821-1828
ISSN:
0730-7268
Subject:
bioassays; biofilm; denitrification; gas chromatography-mass spectrometry; hydroxylation; metabolites; mixed culture; nitrification; nitrifying bacteria; quinoline; reversed-phase high performance liquid chromatography; thin layer chromatography; toxicity testing
Abstract:
... This article reports for the first time the degradation pathways of quinoline, isoquinoline, and methylquinolines by a mixed culture in a biofilm under nitrate-reducing conditions. A simple reverse-phase high-performance liquid chromatography method using ultraviolet detection at 223 nm for determination of seven quinoline analogues and 15 metabolites was developed, and gas chromatography-mass spe ...
DOI:
10.1897/1551-5028(1997)016<1821:DPOQIA>2.3.CO;2

37. Destruction of 2,4,6-Trinitrotoluene by Fenton Oxidation

Author:
Z. M. Li; S. D. Comfort; P. J. Shea
Source:
Journal of environmental quality 1997 v.26 no.2 pp. 480-487
ISSN:
0047-2425
Subject:
decarboxylation; hydrogen peroxide; hydroxylation; iron; mineralization; moieties; nitrates; oxalates; oxalic acid; oxidation; pH; polluted soils; slurries; soil water; stoichiometry; temperature; trinitrotoluene
Abstract:
... Past disposal practices at munitions production facilities have generated numerous acres of 2,4,6-trinitrotoluene (TNT)-contaminated soil. We determined the potential of the Fenton reagent (Fe²⁺ and H₂O₂) to remediate TNT contamination in water, aqueous extracts of contaminated soil, and soil-water slurries. The effects of H₂O₂ and Fe²⁺ concentrations, solution pH, temperature, and initial TNT con ...
DOI:
10.2134/jeq1997.00472425002600020020x

38. Effects of cations, temperature, and creosote on degradation of indole by Desulfobacterium indolicum (DSM 3383)

Author:
Licht, D.; Arvin, E.; Ahring, B.K.
Source:
Environmental toxicology and chemistry 1997 v.16 no.2 pp. 202-206
ISSN:
0730-7268
Subject:
Desulfobacterium indolicum; bacteria; calcium; cations; creosote; culture media; hydroxylation; magnesium; potassium; quinoline; seawater; sodium; temperature
Abstract:
... This work describes the activity of Desulfobacterium indolicum under different conditions. Hydroxylation of indole by the sulfate-reducing marine bacterium D. indolicum was related to the concentration of Na+ and Mg2+, whereas K+ and Ca2+ had no influence. Hydroxylation of indole by D. indolicum was possible in normal medium with cation concentrations corresponding to seawater at low temperatures ...
DOI:
10.1897/1551-5028(1997)016<0202:EOCTAC>2.3.CO;2

39. Hydroxyl Radical-scavenging Effects of Spices and Scavengers from Brown Mustard (Brassica nigra)

Author:
Shin-Kyo Chung; Toshihiko Osawa; Shunro Kawakishi
Source:
Bioscience, biotechnology, and biochemistry 1997 v.61 no.1 pp. 118-123
ISSN:
1347-6947
Subject:
Brassica juncea; Brassica nigra; allspice; benzoic acid; biotechnology; hydroxylation; methanol; oregano; oxidation; sinapic acid; sodium; thyme
Abstract:
... The effects of methanol extracts of 51 spices on ·OH scavenging were studied in detail. 2-Deoxyribose oxidation and sodium benzoic acid hydroxylation methods were used for detecting the scavenging activity of ·OH. Mustard varieties, thyme, oregano, clove, and allspice all exhibited strong ·OH-scavenging activity. In particular, 3 varieties of mustard had above 90% ·OH-scavenging activity with a 1 ...
DOI:
10.1271/bbb.61.118

40. Isolation of new 6-methylnicotinic-acid-degrading bacteria, one of which catalyses the regioselective hydroxylation of nicotinic acid at position C2

Author:
Tinschert, A.; Kiener, A.; Heinzmann, K.; Tschech, A.
Source:
Archives of microbiology 1997 v.168 no.5 pp. 355-361
ISSN:
0302-8933
Subject:
Burkholderia; Ralstonia; bacteria; carbon; drugs; energy; herbicides; hydroxylation; niacin; nucleotide sequences; ribosomal RNA; sequence homology
Abstract:
... 2-Hydroxynicotinic acid is an important building block for herbicides and pharmaceuticals. Enrichment strategies to increase the chances of finding microorganisms capable of hydroxylating at the C2 position and to avoid the degradation of nicotinic acid via the usual intermediate, 6-Hydroxynicotinic acid, were used. Three bacterial strains (Mena 23/3-3c, Mena 25/4-1, and Mena 25/4-3) were isolated ...
DOI:
10.1007/s002030050509
PubMed:
9325423

41. Metabolism of hydroxy fatty acids in developing seeds in the genera Lesquerella (Brassicaceae) and Linum (Linaceae)

Author:
Reed, D.W.; Taylor, D.C.; Covellol P.S.
Source:
Plant physiology 1997 v.114 no.1 pp. 63-68
ISSN:
0032-0889
Subject:
hydroxylation; biosynthesis; quantitative analysis; linolenic acid; Linum usitatissimum; developmental stages; hydroxy fatty acids; Physaria fendleri; seed oils; biochemical pathways; Lesquerella lyrata; chemical constituents of plants; catalytic activity; stearoyl-CoA desaturase; metabolites; seed development
Abstract:
... Members of the genus Lesquerella produce seed oil that contains a high proportion of hydroxy fatty acids (HFAs). There are three groups of Lesquerella species that are distinguished by their most abundant seed oil fatty acid: lesquerolic acid (20:1OH; e.g. Lesquerella fendleri), densipolic acid (18:2OH; e.g. Lesquerella kathryn), and auricolic acid (20:2OH; e.g. Lesquerella auriculata). To investi ...

42. Spice Constituents Scavenging Free Radicals and Inhibiting Pentosidine Formation in a Model System

Author:
Tomoko Oya; Toshihiko Osawa; Shunro Kawakishi
Source:
Bioscience, biotechnology, and biochemistry 1997 v.61 no.2 pp. 263-266
ISSN:
1347-6947
Subject:
allspice; alpha-tocopherol; biomarkers; biotechnology; cloves; diabetes mellitus; erythrocyte membrane; free radicals; glycation; hydroxyl radicals; hydroxylation; isomers; malondialdehyde; methanol; oxygen; pentosidine; rabbits
Abstract:
... Many antioxidants have been found in spices and herbs, and some of them are well known as strong scavengers of active oxygen radicals. We have isolated active products, which markedly inhibited the formation of malondialdehyde (MDA) from 2-deoxyribose and the hydroxylation of benzoate with the hydroxyl radical, from methanol extracts of allspice and clove. Pimentol from allspice, and biflorin and ...
DOI:
10.1271/bbb.61.263

43. Zinc deficiency affects the levels of endogenous gibberellins in Zea mays L

Author:
Sekimoto, H.; Hoshi, M.; Nomura, T.; Yokota, T.
Source:
Plant & cell physiology 1997 v.38 no.9 pp. 1087-1090
ISSN:
0032-0781
Subject:
Zea mays; quantitative analysis; zinc; brassinosteroids; nutrient deficiencies; stress response; gibberellins; chemical constituents of plants; indole acetic acid; hydroxylation
Abstract:
... Zinc deficiency in Zea mays L. markedly reduced the level of GA1, but not GA20, suggesting blockage of 3 beta-hydroxylation. The level of IAA was also decreased although not as markedly. Castasterone was affected less than IAA by zinc deficiency. ...
DOI:
10.1093/oxfordjournals.pcp.a029276

44. Identification and Characterization of Acinetobacter sp. CNU961 Able to Grow with Phenol at High Concentrations

Author:
Kwang Cheol JEONG; Eun Ye JEONG; Tay Eak HWANG; Sang Ho CHOI
Source:
Bioscience, biotechnology, and biochemistry 1998 v.62 no.9 pp. 1830-1833
ISSN:
1347-6947
Subject:
Acinetobacter; biotechnology; catechol; enzymes; genetic complementation test; hydroxylation; mutagens; phenol; polypeptides
Abstract:
... An Acinetobacter sp., strain CNU961, with a higher tolerance to phenol was isolated, and identified through a set of taxonomic studies and a genetic complementation test. Enzymatic and mutagenic studies found that the strain dissimilate phenol by hydroxylation to catechol followed by an ortho-ring cleavage pathway to further mineralize it. The phenol hydroxylase, which is an inducible enzyme and r ...
DOI:
10.1271/bbb.62.1830

45. Methanotrophs, Methylosinus trichosporium OB3b, sMMO, and Their Application to Bioremediation

Author:
Jonathan P. Sullivan; David Dickinson; Howard A. Chase
Source:
Critical reviews in microbiology 1998 v.24 no.4 pp. 335-373
ISSN:
1549-7828
Subject:
Methylosinus trichosporium; alkenes; aromatic compounds; biodegradation; biomass; bioremediation; carbon; catalytic activity; chloral hydrate; cleaners; copper; cost effectiveness; energy; enzyme inhibitors; epoxidation reactions; ethers; groundwater; hydroxylation; industrial applications; metabolites; methane; methane monooxygenase (soluble); methanotrophs; oxidation; pollutants; rivers; sediments; soil; solvents; toxicity; trichloroethylene
Abstract:
... One of the most problematic groups of the USEPA and EU priority pollutants are the halogenated organic compounds. These substances have a wide range of industrial applications, such as solvents and cleaners. Inadequate disposal techniques and accidental spillages have led to their detection in soil, groundwater, and river sediments. Persistence of these compounds in the environment has resulted fr ...
DOI:
10.1080/10408419891294217
PubMed:
9887367

46. Microbial Oxidation of KE-298 Metabolites by Rhizopus sp. and Rhodococcus sp. Strains

Author:
Joji SASAKI; Hideo YOSHIDA; Kazuyuki TOMISAWA; Kimiyo TAKESHITA; Takashi ADACHI
Source:
Bioscience, biotechnology, and biochemistry 1998 v.62 no.6 pp. 1048-1054
ISSN:
1347-6947
Subject:
Rhizopus; biotechnology; carbon; cytochrome P-450; diastereomers; fermenters; hexadecane; hydroxylation; metabolites; metyrapone; oxidation
Abstract:
... The metabolites of the antirheumatic agent KE-298 in humans, (-)-(2R)-M-4 [(-)-(2R)-4-(4-hydroxymethylphenyl)-2-methylthiomethyl-4-oxobutanoic acid], (-)-(2R)-M-5 [diastereomers of (-)-(2R)-4-(4-hydroxymethyl-phenyl)-2-methylsulfinyl-methyl-4-oxobutanoic acid], (-)-(2R)-M-6 [(-)-(2R)-4-(4-carboxyphenyl)-2-methylthio-methyl-4-oxobutanoic acid], and (-)-(2R)-M-7 [di- astereomers of (-)-(2R)-4-(4-car ...
DOI:
10.1271/bbb.62.1048

47. Piperonylic acid, a selective, mechanism-based inactivator of the trans-cinnamate 4-hydroxylase: a new tool to control the flux of metabolites in the phenylpropanoid pathway

Author:
Schalk, M.; Cabello-Hurtado, F.; Pierrel, M.A.; Atanossova, R.; Saindrenan, P.; Werck-Reichhart, D.
Source:
Plant physiology 1998 v.118 no.1 pp. 209-218
ISSN:
0032-0889
Subject:
Tobacco mosaic virus; biosynthesis; scopoletin; coumaric acids; cinnamic acid; enzyme inhibitors; biochemical pathways; Nicotiana tabacum; structure-activity relationships; leaves; hydroxylation; enzyme activity; oxygenases; cell suspension culture; metabolites
Abstract:
... Piperonylic acid (PA) is a natural molecule bearing a methylenedioxy function that closely mimics the structure of transcinnamic acid. The CYP73A subfamily of plant P450s catalyzes trans-cinnamic acid 4-hydroxylation, the second step of the general phenylpropanoid pathway. We show that when incubated in vitro with yeast-expressed CYP73A1, PA behaves as a potent mechanism-based and quasi-irreversib ...

48. Potent Antioxidative Isoflavones Isolated from Soybeans Fermented with Aspergillus saitoi

Author:
Hideo ESAKI; Hiromichi ONOZAKI; Yasujiro MORIMITSU; Shunro KAWAKISHI; Toshihiko OSAWA
Source:
Bioscience, biotechnology, and biochemistry 1998 v.62 no.4 pp. 740-746
ISSN:
1347-6947
Subject:
Aspergillus; antioxidant activity; biotechnology; daidzein; fermentation; gel chromatography; genistein; hydroxylation; lipids; oils
Abstract:
... Two potent antioxidative isoflavones were isolated from soybeans fermented with Aspergillus saitoi by silica gel column chromatography and preparative HPLC, using ODS column, or in addition, Toyopearl HW-40 column chromatography. The purified AS-13 and AS-9B compounds were identified as 8-hydroxydaidzein (8-OHD) and 8-hydroxygenistein (8-OHG), respectively, by MS, and ¹H-NMR, ¹³C-NMR and HMBC spec ...
DOI:
10.1271/bbb.62.740

49. The Coumarin 7-Hydroxylation Microassay in Living Hepatic Cells in Culture

Author:
M. Teresa Donato; José V. Castell; Maria José Gómez-Lechón
Source:
ATLA. Alternatives to laboratory animals v.26 no.2 pp. 213-223
ISSN:
0261-1929
Subject:
automation; biochemical pathways; coumarin; dogs; fluorescence; fluorometry; hepatocytes; hepatoma; humans; hydrolysis; hydroxylation; laboratories; methoxsalen; rats
Abstract:
... Coumarin 7-hydroxylation was evaluated in hepatic cells from various species, cultured in 96-well plates. This microassay involved incubating living cultured cells with the substrate, followed by fluorimetric quantification of the product released into the culture supernatant, after hydrolysis of the conjugates of 7-hydroxycoumarin that were formed. Fluorescence was measured directly in the wells ...
DOI:
10.1177/026119299802600206
PubMed:
26043399

50. The influence of carbon source on the level and composition of ceramides of the Candida lipolytica yeast

Author:
Rupcic, J.; Mesaric, M.; Maric, V.
Source:
Applied microbiology and biotechnology 1998 v.50 no.5 pp. 583-588
ISSN:
0175-7598
Subject:
Yarrowia lipolytica; carbon; ceramides; fatty acid composition; fatty acids; gas chromatography; glucose; hexadecane; hydroxylation; methanolysis; thin layer chromatography; yeasts
Abstract:
... Candida lipolytica yeast was grown batchwise on two different carbon sources, glucose and n-hexadecane. Free ceramides were quantitatively isolated from sphingolipid fractions of total lipids by a combination of column chromatography and preparative thin-layer chromatography. Their composition, after acid methanolysis, was analysed by gas-liquid chromatography. The ceramide content accounted for 2 ...
DOI:
10.1007/s002530051339
PubMed:
9866177