Exopolymers from curdlan production: incorporation of glucose-related sugars by Agrobacterium sp. strain ATCC 31749

1997 ◽  
Vol 43 (2) ◽  
pp. 149-156 ◽  
Author(s):  
Jin W. Lee ◽  
Walter G. Yeomans ◽  
Alfred L. Allen ◽  
David L. Kaplan ◽  
Frank Deng ◽  
...  
Keyword(s):  
Gas Chromatography ◽  
Culture Conditions ◽  
Water Soluble ◽  
Gas Chromatography Mass Spectrometry ◽  
Strain Atcc ◽  
Mineral Salts ◽  
Aerobic Culture ◽  
Nuclear Magnetic Resonance Spectrometry ◽  
Magnetic Resonance Spectrometry ◽  
Curdlan Production

Three different exopolymers were purified from cultures of Agrobacterium sp. strain ATCC 31749 grown in a mineral salts medium containing 2% glucose at 30 °C for 5 days under aerobic culture conditions. These exopolymers were curdlan (extracellular, homo-β-(1-3)-glucan, water insoluble at neutral pH), a water-soluble noncurdlan-type exopolymer A (WSNCE-A), and a water-soluble noncurdlan-type exopolymer B (WSNCE-B). Curdlan, WSNCE-A, and WSNCE-B composed by weight 61, 27, and 12%, respectively, of the exopolymer produced from glucose. Compositions of all polymers were confirmed by gas chromatography (GC) and gas chromatography – mass spectrometry (GC–MS). The WSNCE-A is composed of glucose and galactose with lower contents of rhamnose. The WSNCE-B consists of glucose and mannose. To biosynthesize modified biopolymers, glucose-related sugars including 3-O-methyl-D-glucose, 2-amino-2-deoxy-D-glucose, and 2-acetamido-2-deoxy-D-glucose (N-acetylglucosamine) were fed separately as the sole carbon source. Using 3-O-methyl-D-glucose, 8 – 12 mol% of the curdlan repeats were 3-O-methyl-D-glucose based on GC and 1H-nuclear magnetic resonance spectrometry. N-Acetylglucosamine was incorporated into WSNCE-A at 10 mol% based on the GC–MS but was not found in curdlan or WSNCE-B.Key words: Agrobacterium sp., curdlan, exopolymer, 3-O-methyl-D-glucose, 2-acetamido-2-deoxy-D-glucose.

scholarly journals Differential Degradation of Bicyclics with Aromatic and Alicyclic Rings by Rhodococcus sp. Strain DK17

2011 ◽  
Vol 77 (23) ◽  
pp. 8280-8287 ◽  
Author(s):  
Dockyu Kim ◽  
Miyoun Yoo ◽  
Ki Young Choi ◽  
Beom Sik Kang ◽  
Tai Kyoung Kim ◽  
...  
Keyword(s):  
Gas Chromatography Mass Spectrometry ◽  
Ring Cleavage ◽  
Content Type ◽  
Aromatic Hydroxylation ◽  
Dead End ◽  
Nuclear Magnetic Resonance Spectrometry ◽  
Magnetic Resonance Spectrometry ◽  
Differential Degradation ◽  
Unique Ability ◽  
Rhodococcus Sp

ABSTRACTThe metabolically versatileRhodococcussp. strain DK17 is able to grow on tetralin and indan but cannot use their respective desaturated counterparts, 1,2-dihydronaphthalene and indene, as sole carbon and energy sources. Metabolite analyses by gas chromatography-mass spectrometry and nuclear magnetic resonance spectrometry clearly show that (i) themeta-cleavage dioxygenase mutant strain DK180 accumulates 5,6,7,8-tetrahydro-1,2-naphthalene diol, 1,2-indene diol, and 3,4-dihydro-naphthalene-1,2-diol from tetralin, indene, and 1,2-dihydronaphthalene, respectively, and (ii) when expressed inEscherichia coli, the DK17o-xylene dioxygenase transforms tetralin, indene, and 1,2-dihydronaphthalene into tetralincis-dihydrodiol, indan-1,2-diol, andcis-1,2-dihydroxy-1,2,3,4-tetrahydronaphthalene, respectively. Tetralin, which is activated by aromatic hydroxylation, is degraded successfully via the ring cleavage pathway to support growth of DK17. Indene and 1,2-dihydronaphthalene do not serve as growth substrates because DK17 hydroxylates them on the alicyclic ring and further metabolism results in a dead-end metabolite. This study reveals that aromatic hydroxylation is a prerequisite for proper degradation of bicyclics with aromatic and alicyclic rings by DK17 and confirms the unique ability of the DK17o-xylene dioxygenase to perform distinct regioselective hydroxylations.

scholarly journals A Potentially Useful Procedure for Conversion of Ethers to Esters

2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Li H ◽  
Mark Z ◽  
Graylion M ◽  
Shen T
Keyword(s):  
Building Blocks ◽  
Cyclic Ether ◽  
Gas Chromatography Mass Spectrometry ◽  
High Yield ◽  
Infrared Spectrometry ◽  
Cyclic Ethers ◽  
Efficient Procedure ◽  
Nuclear Magnetic Resonance Spectrometry ◽  
Magnetic Resonance Spectrometry ◽  
Reaction Processes

This communication reports a catalytic system for transformation of ethers into their corresponding esters, especially for cyclic ethers. This efficient procedure was developed as part of our efforts to synthesize nucleoside building blocks and their derivatives. Gas Chromatography-Mass Spectrometry (GC-MS) monitored the reaction processes, Nuclear Magnetic Resonance Spectrometry (NMR), and Infrared Spectrometry (IR) were used to verify the structure of the products. The conversions of Tetrahydrofuran (THF) and other cyclic ether into lactones were accomplished in high yield, over 95%. This approach could be extended too many types of ethers to produce directly corresponding esters simply. Four representatives of ethers were investigated. Cyclic ethers have the higher yields. Linear ethers gave lower yields. The reaction on methoxylcarbon or methyl ether carbon was not observed. The reacted catalyst can be reused over several times. For each reusing, only drops of sulfuric acid need to be added. Nevertheless, the asymmetric ethers selectivity needs to be addressed in future studies.

Hyperaccumulation of manganese in the rainforest tree Austromyrtus bidwillii (Myrtaceae) from Queensland, Australia

2002 ◽  
Vol 29 (7) ◽  
pp. 899 ◽  
Author(s):  
Sjaan D. Bidwell ◽  
Ian E. Woodrow ◽  
George N. Batianoff ◽  
Jens Sommer-Knudsen
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Organic Acids ◽  
Water Soluble ◽  
Gas Chromatography Mass Spectrometry ◽  
Leaf Extracts ◽  
The World ◽  
Molar Equivalent ◽  
Insoluble Compounds ◽  
First Time

Throughout the world, over 400 species of plants are known to accumulate large quantities of metals in their shoots (`hyperaccumulators'), but of these, relatively few accumulate manganese (Mn). We have identified for the first time an Australian native hyperaccumulator of Mn, Austromyrtus bidwillii (Benth.) Burrett (Myrtaceae). Concentrations of Mn up to 19 200 µg g-1 were measured in dried leaves of this rainforest tree, and young bark was found to contain up to 26 500 µg g-1 Mn. Approximately 40% of the Mn in the leaves is readily extracted with water, suggesting that some of the Mn is associated with water-soluble compounds such as organic acids. Organic acids present in appreciable amounts in leaf extracts of A. bidwillii were identified and quantified by HPLC and gas chromatography-mass spectrometry. The following organic acids (in order of concentration) were present: succinic > malic ≥ malonic > oxalic >> citric acid. The concentration of total organic acids was on average 123 000 µg g-1 dry tissue, which amounted to approximately three times the molar equivalent of Mn and two times the molar equivalent of total cations (Mn, Mg and Ca), demonstrating that organic anions were in excess. The Mn remaining after water extraction ((61 ± 3.9%) could be extracted with 0.2M HCl, suggesting that a significant portion of the Mn is associated with the cell wall (perhaps replacing Ca) or is present as other insoluble compounds.

Generation of water-soluble organic acids from kerogen during hydrous pyrolysis: implications for porosity development

1987 ◽  
Vol 51 (362) ◽  
pp. 495-503 ◽  
Author(s):  
T. I. Eglinton ◽  
C. D. Curtis ◽  
S. J. Rowland
Keyword(s):  
Gas Chromatography ◽  
Organic Acids ◽  
Oil Field ◽  
Water Soluble ◽  
Gas Chromatography Mass Spectrometry ◽  
Low Molecular Weight ◽  
Secondary Porosity ◽  
Hydrous Pyrolysis ◽  
Kerogen Type ◽  
Artificial Maturation

AbstractConcentrations of organic acids ranging up to several thousand parts per million have previously been found in oil-field waters. These acids are of interest because of their potential to enhance porosity by the dissolution of carbonates and aluminosilicates. They are believed to be generated from organic geopolymers (kerogen) in the late-diagenetic-early-catagenetic stage of thermal maturation.During the course of artificial maturation experiments in which kerogens of varying type were heated in the presence of water (so-called ‘hydrous pyrolysis’) and different minerals, the distribution and abundance of low molecular weight water-soluble acids were determined by gas chromatography and gas chromatography-mass spectrometry. Preliminary results suggest that significant quantities of mono- and di-carboxylic acids are produced during hydrous pyrolysis. The amounts and types of acid appear to vary as a function of kerogen type, maturity and mineralogy. Implications of these findings regarding the development of secondary porosity are discussed.

Feeding Stimulant in Cinnamomum camphora for the Common Bluebottle, Graphium sarpedon nipponum (Lepidoptera: Papilionidae)

2010 ◽  
Vol 65 (9-10) ◽  
pp. 571-576 ◽  
Author(s):  
Jing Li ◽  
Ryu Wakui ◽  
Masanori Horie ◽  
Yoshichika Nishimura ◽  
Yoshihide Nishiyama ◽  
...  
Keyword(s):  
Methanol Extract ◽  
Gas Chromatography Mass Spectrometry ◽  
Cinnamomum Camphora ◽  
Highly Active ◽  
Water Layers ◽  
Bioassay Guided Fractionation ◽  
Feeding Activities ◽  
Nuclear Magnetic Resonance Spectrometry ◽  
Magnetic Resonance Spectrometry ◽  
The Common

The acceptance of camphor tree (Cinnamomum camphora) as a host plant for the larvae of common bluebottle (Graphium sarpedon nipponum) was explained by the presence of feeding stimulants in the leaves. When the active methanol extract of C. camphora leaves was separated into hexane and water layers, both layers showed high feeding activities for the larvae of G. sarpedon nipponum. Bioassay-guided fractionation of the hexane layer resulted in the isolation of a highly active compound, which was identified as α-linolenic acid by nuclear magnetic resonance spectrometry and gas chromatography-mass spectrometry.

scholarly journals METABOLIC PROFILE ASSESSMENT OF PHYTOCHEMICALS IN CEIBA PENTANDRA (L.) GAERTN, FROM ZARIA CITY, NIGERIA

2020 ◽  
Vol 4 (3) ◽  
pp. 426-436
Author(s):  
A. S. Dalhatu ◽  
S. T. Imman ◽  
M. M. Namadina ◽  
Zainab Muhammad Sani ◽  
Y. Y. Muhammad
Keyword(s):  
Secondary Metabolites ◽  
Plant Extracts ◽  
Stem Bark ◽  
Gas Chromatography Mass Spectrometry ◽  
Leaf Extracts ◽  
Chemical Structures ◽  
Ceiba Pentandra ◽  
Standing Trees ◽  
Nuclear Magnetic Resonance Spectrometry ◽  
Magnetic Resonance Spectrometry

Ceiba pentandra (Silk cotton) is a multipurpose tree in the province of Zaria city, Kaduna State, Nigeria, which is being exposed to uncontrolled exploitation by the natives. Samples of the plant were collected from standing trees located at Zaria city: Kofar Gayan, Rimin Doko, Kwarbai, Kofar Doka and Kofar Kibo. The study was aimed at assessing the secondary metabolites in C. pentandra plant extracts of leaves, stem barks and roots This was achieved through subjecting the extracts to phytochemical screening and gas chromatography/mass spectrometry fingerprinting (metabolic profiling) of phytochemical markers. The results of the screening revealed flavonoids, saponins, steroids, tannins, triterpenoids and reducing sugars to be present in moderate variation, across the extracts. The metabolic fingerprinting indicated high variation among the phytochemicals obtained from the plant extracts. Where, twenty-seven (27) secondary metabolites were predicted from the methanol leaf extracts, twenty-five (25) from the methanol stem bark extracts and twenty-seven (27) from the methanol root extracts, out of which only one of the metabolites (2-hydroxypropyl ether) was predicted in all the extracts. Therefore, for a clearer and broader identification of these phytochemical markers, Nuclear Magnetic Resonance spectrometry (NMR) should be employed to determine the detailed chemical structures of the identified metabolites, which will help in determining their functions and how they can be used to improve the biodiversity of these tree species.

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