Microbial petroleum degradation: application of computerized mass spectrometry

1975 ◽  
Vol 21 (11) ◽  
pp. 1760-1767 ◽  
Author(s):  
J. D. Walker ◽  
R. R. Colwell ◽  
L. Petrakis

An analytical procedure is presented for obtaining detailed characterization of petroleum hydrocarbons which undergo microbial degradation. The procedure includes column chromatographic separation and characterization of the resulting fractions by mass spectrometry and gas chromatography. The use of computerized low-resolution mass spectrometry is offered as a method for assessing microbial degradation of petroleum. This method provides information which cannot, at the present time, be obtained by other available analytical methods. Use of this method to evaluate degradation of a South Louisiana crude oil by a mixed culture of estuarine bacteria revealed that asphaltenes and resins increased by 28% after degradation, while saturates and aromatics decreased by 83.4% and 70.5%, respectively. Most of the normal and branched-chain alkanes were degraded (96.4%), but an increase in long-chain alkanes (C28–C32) after degradation was observed by gas–liquid chromatography. Susceptibility of cycloalkanes to degradation was less as the structure varied, i.e., 6-ring > 1-ring > 2-ring > 3-ring > 5-ring > 4-ring. Susceptibility of aromatic components to degradation decreased with increase in the number of rings, viz., monoaromatics > diaromatics > triaromatics > tetraaromatics > pentaaromatics. Aromatic nuclei containing sulfur were twice as refractory as non-sulfur analogs.

1974 ◽  
Vol 1 (2) ◽  
pp. 183 ◽  
Author(s):  
KF Faull ◽  
BG Coombe ◽  
LG Paleg

Two gibberellins, one GA1-like, the other GA3-like, were identified in the extracts of roots and tops of 8-,11- and 15-day-old barley seedlings by paper chromatography, paper electrophoresis, thin-layer chromatography, gas-liquid chromatography and bioassay procedures, followed by combined gas chromatography-mass spectrometry. The amounts of gibberellins in the seedlings ranged from 7 to 11 ng per plant. The concentrations of gibberellins in the seedlings were 32-320 ng/g dry weight and 5-28 ng/g fresh weight; concentrations in the roots were higher than those in the shoots.


1971 ◽  
Vol 54 (4) ◽  
pp. 801-807
Author(s):  
David L Stalling ◽  
James N Huckins

Abstract The isomer composition of the Aroclor 1200 series was characterized by GLC-MS, using temperature programming and SE-30 support-coated, open-tubular capillary columns. A method is described for the preparation and purification of 36Cl-labeled Aroclors 1248 and 1254. Neutron irradiation of the commercial material was used to prepare the 36Cl-labeled material. Purification of the irradiated product was accomplished by silicic acid column chromatography. Yields of the purified product were between 63 and 99%, with no detectable alteration of the isomer composition; 10% of the 36C1 produced was associated with the unchanged PCB isomers and the remaining radioactivity was contained in polychlorinated terphenyls. The terphenyls were produced by irradiation polymerization, and they were easily separated from the PCB components. Mass spectrometry, utilizing either temperature programmed GLC or direct probe sample introduction, was used to characterize the irradiation products. The radioactive materials are being utilized in experiments to determine uptake and metabolism of PCB by aquatic organisms.


2017 ◽  
Vol 89 (10) ◽  
pp. 5404-5412 ◽  
Author(s):  
Rabah Gahoual ◽  
Anna-Katharina Heidenreich ◽  
Govert W. Somsen ◽  
Patrick Bulau ◽  
Dietmar Reusch ◽  
...  

Foods ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 75 ◽  
Author(s):  
Haocheng Liu ◽  
Kejing An ◽  
Siqi Su ◽  
Yuanshan Yu ◽  
Jijun Wu ◽  
...  

Mangoes (Mangifera indica L.) are wildly cultivated in China with different commercial varieties; however, characterization of their aromatic profiles is limited. To better understand the aromatic compounds in different mango fruits, the characteristic aromatic components of five Chinese mango varieties were investigated using headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry-gas chromatography-olfactometry (GC-MS-O) techniques. Five major types of substances, including alcohols, terpenes, esters, aldehydes, and ketones were detected. GC-O (frequency detection (FD)/order-specific magnitude estimation (OSME)) analysis identified 23, 20, 20, 24, and 24 kinds of aromatic components in Jinmang, Qingmang, Guifei, Hongyu, and Tainong, respectively. Moreover, 11, 9, 9, 8, and 17 substances with odor activity values (OAVs) ≥1 were observed in Jinmang, Qingmang, Guifei, Hongyu, and Tainong, respectively. Further sensory analysis revealed that the OAV and GC-O (FD/OSME) methods were coincided with the main sensory aromatic profiles (fruit, sweet, flower, and rosin aromas) of the five mango pulps. Approximately 29 (FD ≥ 6, OSME ≥ 2, OAV ≥ 1) aroma-active compounds were identified in the pulps of five mango varieties, namely, γ-terpinene, 1-hexanol, hexanal, terpinolene trans-2-heptenal, and p-cymene, which were responsible for their special flavor. Aldehydes and terpenes play a vital role in the special flavor of mango, and those in Tainong were significantly higher than in the other four varieties.


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