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1Author    Abdussalam Maihub, HuiBi Xu, GerhardN. SchrauzerRequires cookie*
 Title    Studies on Vitamin B12 and Related Compounds, 51 [1] Direct Syntheses of Alkylcobalamins from Alkanes and Vitamin B12r under "Oxidizing-Reducing" Conditions  
 Abstract    Syntheses of methylcobalamin from methane, and of n-alkylcobalamins from n-alkanes (C2 C10) and vitamin Bi2r are described. The compounds are formed under "oxidizing-reducing" conditions: Oxygen radicals (02~, HOO -, and HO') are generated from the reaction of O2 with reducing metal ions, notably V +3 (aq) and abstract hydrogen from the alkane substrates. The resulting alkyl radicals are captured by vitamin Bj2r with high efficiency to yield alkylcobalamins. The reactions take place at room temperature in mildly alkaline or acidic solutions. In addition to n-alkylcobalamins, the preparation of neopentylcobalamin from neopentane, of isobutylcobalamin from isobutane, and of several cycloalkylcobalamins from cycloalkanes, is also reported. Methyl radicals generated in D20 from CH4 under "oxidizing-reducing" conditions are reduced to yield CH3D. 
  Reference    Z. Naturforsch. 35b, 1435—1438 (1980); received April 25 1980 
  Published    1980 
  Keywords    Alkylcobalamins, Synthesis, Alkanes 
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 TEI-XML for    default:Reihe_B/35/ZNB-1980-35b-1435.pdf 
 Identifier    ZNB-1980-35b-1435 
 Volume    35 
2Author    Paul-Gerhard GülzRequires cookie*
 Title    of Jojoba (Simmondsia chinensis [Link] Schneider)  
 Abstract    Epicuticular waxes were extracted with hexane from dry Jojoba pericarp and seed. These cuticular waxes consisted of hydrocarbons, wax esters, free acids, free alcohols and sterols; additionally aldehydes were found in the wax obtained from seed coats. The hydrocarbon fraction contained a homologous series of «-alkanes and branched alkanes but no alkenes. The composition of the wax esters of the cuticular wax was similar to that of the cotyledons. The esters are composed of monounsaturated long chain acids and alcohols. 
  Reference    Z. Naturforsch. 37c, 1053—1056 (1982); received June 7 1982 
  Published    1982 
  Keywords    Jojoba Fruits, Pericarp, Seed Coat, «-Alkanes, Branched Alkanes 
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 TEI-XML for    default:Reihe_C/37/ZNC-1982-37c-1053.pdf 
 Identifier    ZNC-1982-37c-1053 
 Volume    37 
3Author    Christoph Syldatk, Siegmund Lang, FritzW. Agner, Victor Wray, Ludger WitteRequires cookie*
 Title    Chemical and Physical Characterization of Four Interfacial-Active Rhamnolipids from Pseudomonas spec. DSM 2874 Grown on /i-Alkanes  
 Abstract    Four extracellular glycolip id s p rod u ced under g r o w th -lim itin g c o n d itio n s w ere iso la ted from the culture broth o f Pseudomonas spec. D SM 2874. A fter p u r ific a tio n by c o lu m n and th ick -la y er chrom atography they were id en tified as a n io n ic rh a m n o lip id s. 'H and '3C -N M R stu d ie s sh o w e d that two o f these, /? (/? (2 -0 -a -L -rh a m n o p y ra n o sy lo x y)d eca n o y l)d eca n o ic a cid and /?(/?(2-0-a-L -rh a m n o p y ran osyl-x-L -rh am n op yran osyloxy)d ecan oyloxy)d ecan oic acid , w ere id en tica l w ith c o m ­ pounds described previously, w h ile the other m ore h y d r o p h ilic c o m p o u n d s, /? (2 -0 -a -L -r h a m n o -p yranosyloxy)decanoic acid and /? (2 -0 -a -L -r h a m n o p y ra n o sy l-ix -L -rh a m n o p y ra n o sy lo x y)d e ca n o ic acid, were new com pounds. Surface and interfacial activity o f the organic crude extract and o f the purified com ponents were determined in different aqueous solutions. The pH -dependence o f surface and interfacial properties o f the two previously described rham nolipids (4, 20. 23) were exam ined in Teorell-Stenhagen-buffer (supplemented with 10% N aC l) at pH 3.0 and pH 9.0. All rham nolipids reduced the surface-tension from 72 to about 30 m N / m and the interfacial-tension from 42 to about 1 m N /m . The critical m icelle concentrations were o f the order o f 5 to 200 mg/1 depending on the structure o f the molecule. 
  Reference    Z. Naturforsch. 40c, 51—60 (1985); received August 20 1984 
  Published    1985 
  Keywords    Pseudomonas, Interfacial-Active, Rham nolipids, «-Alkanes, Structure-Eludication 
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 TEI-XML for    default:Reihe_C/40/ZNC-1985-40c-0051.pdf 
 Identifier    ZNC-1985-40c-0051 
 Volume    40 
4Author    C. Syldatk, S. Lang, U. Matulovic, F. W. AgnerRequires cookie*
 Title    Production of Four Interfacial Active Rhamnolipids from /i-Alkanes or Glycerol by Resting Cells of Pseudomonas species DSM 2874  
 Abstract    In a simple phosphate buffer or a sodium chloride solution resting cells o f Pseudom onas spec. DSM 2874 produced up to 15 g/1 o f different rham nolipids. The rham nolipid com position o f the organic crude extract depended on the temperature during the cultivation and on the C-source. The optimal sodium chloride concentration for rham nolipid form ation was about 100 mM/1 and the optimal phosphate buffer concentration about 65 mM/1. The optim al pH -value for the production o f rhamnolipids from «-alkanes or glycerol was in the range pH 6.0 -7 . 2 . W hile rhamnolipid formation with glycerol as the sole C-source show ed a w ide optim um ranging from 27 ° up to 37 °C, production o f rhamnolipids from «-alkanes had a sharp optim um at 37 °C. The addition o f multivalent cations, different N -sources and E D T A caused an inhibition o f rhamnolipid formation, while the «-alkane concentration had no influence. Specific rham nolipid formation decreased with increasing cell concentration. Various C-sources were suitable for the formation o f rhamnolipids by resting cells o f Pseudom onas spec. D S M 2874. Yields, which were comparable to those obtained on «-alkanes or glycerol, were found for stearic acid, fatty alcohols and vegetable oils. A study o f the time course o f glycolipid production o f resting cells was carried out in a 20 1-biorcactor with an intensor system and with «-tetradecane as the sole C-source. 
  Reference    Z. Naturforsch. 40c, 61—67 (1985); received August 2 0 /0 c to b e r 23 1984 
  Published    1985 
  Keywords    Pseudomonas, Interfacial-Active, Rham nolipids, «-Alkanes, Resting Cells 
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 TEI-XML for    default:Reihe_C/40/ZNC-1985-40c-0061.pdf 
 Identifier    ZNC-1985-40c-0061 
 Volume    40 
5Author    A. B. Attygalle, J.P J Billen, B. D. Jackson, E. D. MorganRequires cookie*
 Title    Morphology and Chemical Contents of Dufour Glands of Pseudomyrmex Ants (Hymenoptera: Formicidae)  
 Abstract    The morphology and ultrastructure of the D ufou r gland o f a pseudomyrmecine ant is de­ scribed. The gland has an unusually large volume but possesses a very thin epithelial lining. Its morphology does not constitute a specific subfamily character as in some ant subfamilies. Analysis by gas chromatography-mass spectrometry o f the glands of three species showed them all to be rich in saturated linear hydrocarbons (C ]7:0 and C i5:0 dom inant) and isopropyl esters of the com mon fatty acids. Each species produces its own characteristic mixture of these substances. The most abundant ester in Pseudomyrmex ferruginea is isopropyl oleate and in P. sp. A it is isopropyl palmitate, in P.flavicornis there alate female o f P. ferruginea contained a very similar 
  Reference    Z. Naturforsch. 45c, 691—697 (1990); received February 16 1990 
  Published    1990 
  Keywords    Pseudomyrmex, Epithelium, Alkanes, Isopropyl Esters 
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 TEI-XML for    default:Reihe_C/45/ZNC-1990-45c-0691.pdf 
 Identifier    ZNC-1990-45c-0691 
 Volume    45 
6Author    Friedrich JüttnerRequires cookie*
 Title    ß-Cyclocitral and Alkanes in Microcystis (Cyanophyceae)  
 Abstract    A tobacco-like odorous compound isolated from a bloom of the blue-green alga M icro cystis w esen b erg ii and a laboratory culture of M . aeruginosa was analysed by gas-liquid chromatography and mass spectrometry. Its structure was determined as /?-cyclocitral. No other monoterpenes have been detected in these and in other blue-green algae. The hydrocarbon content was 0.10 — 0.18% 
  Reference    (Z. Naturforsch. 31c, 491 [1976]; received August 6 1976) 
  Published    1976 
  Keywords    Microcystis, Monoterpene, ^-Cyclocitral, Alkanes 
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 TEI-XML for    default:Reihe_C/31/ZNC-1976-31c-0491.pdf 
 Identifier    ZNC-1976-31c-0491 
 Volume    31