The metabolism of carbohydrates by extremely halophilic bacteria: the identification of lactobionic acid as a product of lactose metabolism by Halobacterium saccharovorum

1978 ◽  
Vol 24 (8) ◽  
pp. 898-903 ◽  
Author(s):  
Geraldine A. Tomlinson ◽  
Maureen P. Strohm ◽  
Lawrence I. Hochstein

Nongrowing cells of Halobacterium saccharovorum oxidized lactose to a product identified as lactobionic acid by thin-layer, paper, and column chromatography, and by identification of the galactose and gluconic acid produced from it after acid hydrolysis. Growing cells oxidized lactose to a product that was identical with lactobionate except that it did not serve as a substrate for galactose oxidase. While the identity of this compound has not been established, it is suggested that the product is lactobionic acid in which the galactose moeity is in the furanose form. Neither lactobionate nor the product produced by growing cells was further metabolized, suggesting that lactose oxidation is not coupled to growth.

1980 ◽  
Vol 18 (7) ◽  
pp. 311-314 ◽  
Author(s):  
S. Yuasa ◽  
A. Shimada ◽  
K. Kameyama ◽  
M. Yasui ◽  
K. Adzuma

2021 ◽  
Vol 55 ◽  
pp. 135-140
Author(s):  
Cristina MOGOSAN ◽  
Ilioara ONIGA ◽  
Mircea TAMAS

We isolated the steroidal saponins from the rhizomes of Polygonatum odoratum (Mill.) Druce with an efficiency of 4.50% which represents 7 fractions identified by thin-layer chromatography (TLC), of which 3 were furostanics and 4 spirostanics. After the acid hydrolysis of the saponins, one aglycone (sapogenine) was identified by TLC. Further, we have determined the physico-chemical and the biological properties of the isolated saponins.


1966 ◽  
Vol 49 (5) ◽  
pp. 1078-1083
Author(s):  
M Osadca ◽  
E DeRitter ◽  
R H Bunnell

Abstract Methods are presented for determining the carotenoids β-apo-8′-carotenaI and canthaxanthin in foods to which they have been added as colorants. They are extracted by blending or by shaking with appropriate solvents, depending on the nature of the sample, and are separated from naturally occurring pigments and other added coloring agents by selective solvent extraction and/or column chromatography. Concentration is measured by spectrophotometric reading at the absorption maximum after the system is brought to isomerization equilibrium by treatment with iodine solution. Thin layer chromatographic procedures are described for confirming the identities and completeness of separation of the carotenoids.


1979 ◽  
Vol 34 (3-4) ◽  
pp. 288-289 ◽  
Author(s):  
M. M. El-Olemy ◽  
J. Reisch

Abstract Batatasin I was shown to occur in the fresh rhizomes of poisonous yam (Dioscorea dumetorum Pax.,). It was isolated by column chromatography and identified by chromatographic and spectral evidence. Two other unknown phenanthrenes were shown to occur by thin-layer chromatography.


Weed Science ◽  
1975 ◽  
Vol 23 (6) ◽  
pp. 508-511 ◽  
Author(s):  
Chu-Huang Wu ◽  
P. W. Santelmann

Herbicide mobility in soils was compared by three laboratory methods. The Rf values calculated from soil thin-layer chromatography correlated closely with those obtained from soil thick-layer chromatography (r = 0.96). Herbicides leached slightly further in slotted column chromatography as compared with the other methods. The working hours required to conduct a study with each method were in the increasing order of thin-layer, thick-layer, and column chromatography. However, the thin-layer method required the longest waiting times, followed by the column and thick-layer chromatography. If radioactive herbicides are not available or obtainable, the thick-layer chromatography is simplest and quickest. The relative mobility of herbicides studied was fluometuron [1,1-dimethyl-3-(α,α,α-trifluoro-m-tolyl)urea] > napropamide [2-(α-naphthoxy)-N,N-diethylpropionamide] > terbutryn [2-(tert-butyl-amino)-4-(ethylamino)-6-(methylthio)-s-triazine] > trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine). Less herbicide mobility was observed in heavier soil than in sandy soil.


1971 ◽  
Vol 54 (5) ◽  
pp. 1027-1031
Author(s):  
J L Ayres ◽  
D J Lee ◽  
R O Sinnhuber

Abstract A new method for the preparation of 14C- and 3H-labeled aflatoxins was devised, using rice as a supporting mold media. Labeled precursors were added to sterile rice and the mixture was inoculated with Aspergillus flavus spores. After a 7 day incubation at 25°C, the toxins were extracted with chloroform and purified by column chromatography and subsequent recrystallization. Aflatoxins B1 and G1 were recovered with 70% efficiency from the culture. Incorporation of radioactivity was examined with glucose-U-14C, sodium acetate-1-14C, and sodium acetate-2-14C. The latter gave the most efficient incorporation of 14C at 0.1% for aflatoxin B1 and 0.05% for aflatoxin G1. Conversion of 3H from tritiated water was 0.006% for aflatoxin B1 and 0.003% for aflatoxin G1. Extensive tests of radiopurity were performed on the labeled toxin which included: recrystallization to constant specific activity, thin layer and column chromatography, and hydrogenation of aflatoxin B1 to tetrahydrodeoxoaflatoxin B1. The rice-culturing technique gave good toxin yields of 1 mg aflatoxin B1/g rice. The purification was simplified by the absence of highly radioactive impurities and no appreciable degradation of labeled toxins was noted throughout extraction and purification.


1992 ◽  
Vol 47 (10) ◽  
pp. 1444-1458 ◽  
Author(s):  
Roland Ferth ◽  
Andreas Baumann ◽  
Wolfgang Robien ◽  
Brigitte Kopp

From leaves and bulbs of Ornithogalum nutans L. (2 n = 28), seventeen cardenolides were isolated by column chromatography, DCCC and TLC. The structure elucidation was performed by means of 1H NMR, 13C NMR, HH-Cosy, HC-Cosy and FAB-MS studies and identification of the sugar moieties by GLC after acid hydrolysis of the cardenolides. Sugar compounds were identified as digitoxose, 3-acetyl-digitoxose, 2-deoxy-allose, 6-deoxy-allose, rhamnose, xylose and apiose. Glycosides of 7β,15β, 16 α-trihydroxy-uzarigenin, 8β,16 α-dihy-droxy, 15-oxo-uzarigenin, 3 β, 11β-dihydroxy, 12-oxo, 18-nor-5 α-card-13-enolid, 11 α-hydroxygitoxigenin, 12-oxo,8, 14β-epoxy-uzarigenin, 8β-hydroxy, 15-oxo-uzarigenin and 12β-hydroxy-oleandrigenin are described for the first time, the presence of oleandrigenin-glycosides in the genus Ornithogalum was not known until now. Ornithogalum nutans L. shows a different cardenolide pattern from the second European species of the section Myogalum (LINK) PETERM. - Ornithogalum boucheanum (KUNTH) ASCHERS.


Sign in / Sign up

Export Citation Format

Share Document