Experiments designed to measure the oxidation and degradation of crude oils by naturally occurring marine microorganisms are presently being conducted. Fifty active oil degrading cultures have been isolated in enriched seawater containing crude oil. Oil degradation has been determined with gas chromatography, wet combustion, and by measurement of surface tension. Normal paraffin hydrocarbons through C-26 are degraded by two different groups of micro organisms-those growing in the oil phase only and those growing in the aqueous phase. Emulsification of the crude oil through production of surfactants was observed in many of the enriched cultures. Microbial degradation of 35 to 55 per cent of oxidizable crude oil occurred within 60 hours.
A flow-through controlled atmosphere packaging system using a number of different carbon dioxide-enriched gaseous compositions was demonstrated to be effective in retarding the growth of microorganisms on fresh swordfish steaks held at 2°C for 22 d. During the first 14 d of storage, Pseudomonas spp. either dominated or represented a major part of the microflora of steaks in all gaseous atmospheres tested. However, in atmospheres containing 70% CO2 or in pure CO2, heterofermentative Lactobacillus spp. and Brochothrix thermosphacta were a major part of the microflora, particularly after the 14th day of storage. Both total volatile nitrogen and trimethylamine, often used as quality indicators for fresh seafoods, increased more slowly for swordfish steaks stored in CO2-enriched atmospheres than steaks stored in air. Advantages of using a controlled atmosphere flow-through system for storage of fresh seafoods include: (a) a stable gas composition, (b) individual portions can be removed from a master package without losing or disrupting the gaseous atmosphere, and (c) volatile off-odors which accumulate during storage in sealed CO2-enriched atmospheres are carried off with the flow-through gas.
Petroleum utilizing microorganisms in flasks containing enriched seawater exhibited a clear metabolic preference for saturated paraffins in a Louisiana crude oil. The rates of oxidation of these compounds were directly proportional to incubation temperature and roughly doubled with a ten degree increase. A pattern of growth consisting of an initially large rate of saturated paraffin oxidation, followed by a decrease and another increase in rate was observed. The initially large rates were attributed to the metabolism of n-paraffins smaller than C-18. No even or odd chain length preference for n-paraffins was indicated. There was no evidence of utilization for aromatic compounds. Application of a microbial culture to an oil slick under simulated field conditions, clearly showed that microbes could accelerate the removal of a Louisiana crude oil from an oil slick on seawater. The rates of oil removal in outdoor, exposed conditions, were twice as large as the rates of evaporative oil loss. The microbes produced a significant change in oil “stickiness”. Measurements indicated the oil was dispersed through microbial activity. The cells preferentially remained at the oil-water interface during the experimental periods.
This paper was prepared for the Second Biennial Symposium on Environmental Conservation presented by the Evangeline Section of the Society of Petroleum Engineers of AIME, to be held in Lafayette, La., Nov. 13–14, 1972. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made. provided agreement to give proper credit is made. Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines. Abstract Mixed populations of petroleum oxidizing bacteria were isolated from a variety of natural environments. Mixed populations were evaluated for hydrocarbon oxidizing capability (in vitro). In vitro studies employing a nutrient salts enriched seawater indicated utilization of saturated paraffins. n-Paraffins from C-10 to C-30, pristane and phytane were utilized. Experiments with large tanks designed to simulate aspects of the environment revealed that crude oil mass cultured marine bacteria applied to an oil slick in a nutrient salts solution would preferentially remain at the oil-water interface preferentially remain at the oil-water interface while degrading the floating oil slick. A wax-nutrient salts composite is now being considered as a method for retaining a source of nutrient salts at the oil-water interface. Introduction Crude oils are being released into the world ocean in increasing amounts. Besides constituting a needless loss to the world petroleum reserves, the effects of crude petroleum reserves, the effects of crude oils on the marine ecosystem may be undesirable. Although crude oils contain hydrocarbons with demonstrable toxicities and carcinogenic properties in pure form (Blumer, 1969), there are no empirical data describing the responses of biological systems to chronic low-level crude oil pollution. While indirect evidence pollution. While indirect evidence indicates that acutely polluted areas recover from massive petroleum spills (Straughan, 1971; Chan, 1972), hydrocarbons associated with hydrocarbon pollutants have been extracted from exposed marine organisms (Blumer, Souza and Sass, 1970; ZoBell, 1971) Complicating an interpretation of this latter phenomenon is a lack of knowledge describing baseline concentrations and types of hydrocarbons in marine organisms and more significantly, the abilities of organisms to metabolize and/or release hydrocarbons after the pollution scarce has been removed (Lee, Sauerheber, and Benson, 1972). Complementing our ignorance of the biological effects of pollutant crude oils upon marine organisms is the fate of crude oil hydrocarbons introduced into the world ocean.
Replacement of coal by petroleum as the major world source of energy has resulted in increasing amounts of petroleum products being released into the environment. The need to quantify and to identify petroleum hydrocarbons in natural waters has presented methodological dif-
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.