ISSN:0006-3592    

DOI:10.1002/bit.260140302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractWithin the framework of a study on the oil biodegradation potential of the sea the ability of aFlavobacterium sp.andBrevibacterium sp.to metabolize a paraffinic crude oil and a chemically defined hydrocarbon mixture was investigated. Major components of the crude oil were identified by combination gas chromatography and mass spectrometry. The rate and extent of total hydrocarbon biodegradation was measured. In addition, CO2evolution from the crude oil was continuously monitored in a shaker‐mounted gas train arrangement. Degradation started after a 2 to 4 day lag period, and reached its maximum within two weeks. At this time up to 60% of the crude oil and 75% of the model hydrocarbon mixture, each added at the level of 1 ml per 100 ml artificial sea water, were degraded. Mineralization(conversion to CO2) was slightly lower due to formation of products and bacterial cell material.n‐Paraffins were preferentially degraded as compared to branched chain hydrocarbons. Biodegradation ofn‐paraffins in the range of C12to C20was simultaneous; no diauxie effects were obs

ISSN:0006-3592    

DOI:10.1002/bit.260140303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractBiodegradation and mineralization of petroleum, added at 1% (v/v) to freshly collected sea water, were measured using gas–liquid chromatographic, residual weight, and CO2‐evolution techniques. Only 3% of the added petroleum was biodegraded and 1% was mineralized in unamended sea water after 18 days of incubation. Added individually, nitrate (10−2M) or phosphate (3.5 × 10−4M) supplements caused little improvement, but when added in combination, they increased petroleum biodegradation and mineralization to 70% and 42%, respectively. Attempts to clean up oil spills with the aid of microorganisms should take into consideration the nutritional deficiencies of s

ISSN:0006-3592    

DOI:10.1002/bit.260140304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractBacterial strains were isolated from California coastal areas which showed the ability to oxidize normal paraffins, iso‐paraffins, and aromatic hydrocarbons in a synthetic seawater medium. The ability to utilize a particular hydrocarbon was established not only on the basis of visible bacterial growth but also through a chromatographic technique which was standardized and which could define the amount of each hydrocarbon consumed by the bacteria in a mixture. Some of the strains exhibited vigorous hydrocarbon oxidation when exposed to synthetic mixtures of hydrocarbons as well as crude oil. Under conditions of aeration and agitation, mixed cultures could destroy approximately 50% of a South Louisiana crude oil in a period of 48 h

ISSN:0006-3592    

DOI:10.1002/bit.260140305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractAn enrichment culture procedure has been used to isolate mixed culture systems which grow upon “Bunker C” fuel oil. When inoculated into a mineral salts aqueous medium containing Bunker C oil, the mixed cultures initiate oil emulsification. Emulsification usually is observed in 24–48 hr. The role of microbes in this emulsification will be discussed. It appears that certain metabolic products produced by the microbe possess properties of surfactants. Bacteria and fungi have been isolated which possess the ability to cause emulsification. Freeze‐dried biomass is also capable of emulsifying oil. Chromatographic analyses of biodegraded Bunker C fuel oil show that microorganisms selectively metabolize then‐paraffin

ISSN:0006-3592    

DOI:10.1002/bit.260140306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractThe transport of insoluble substrates such as hydrocarbons to microorganisms is often postulated to be dictated by the availability of the hydrocarbon surface area. Many publications, qualitative and quantitative, have appeared to substantiate this hypothesis. Experiments have been performed in our laboratory to assess the absolute values of the interfacial area of hexadecane as the carbon source for the growth ofCandida intermedia. A sedimentometer, mounted directly in the fermentor, was used to measure the interfacial hydrocarbon area during active growth of this organism. The specific hydrocarbon interfacial area was found to be directly related to the impeller speed, hydrocarbon concentration and surfactant concentration in a 1‐liter working volume, turbine‐agitated fermentor. The specific growth rate was in turn found to be directly related to the specific hydrocarbon interfacial area. Lastly, cessation of logarithmic growth and onset of linear growth was found at all instances to be governed by the specific hydrocarbon surface a

ISSN:0006-3592    

DOI:10.1002/bit.260140307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractSix soil isolates were grown on a petroleum sulfonate medium and analyzed chromatographically to determine their amino acid composition. The organisms were also examined to determine their growth rate in the petroleum medium, their per cent conversion of hydrocarbon to dry cell mass, their protein content, and their possible use as a food or food supplement. It was found that the isolates varied extensively as to their amino acid composition. Several of the isolates proved to convert the hydrocarbons to cell mass with relative ease. The proteins of four of the isolates appear to be suitable as a good food source, and the protein of one of the remaining isolates appears to be a very good food supplement.

ISSN:0006-3592    

DOI:10.1002/bit.260140308

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractCultivation ofCorynebacterium hydrocarboclastus, which is capable of synthesizing an extracellular polymer and utilized hydrocarbons, has been reported. Growth studies in shake flasks and fermenters were made to obtain maximum polymer production. Polymer formation was found to be growth associated. The highest level of polymer accumulation was attained after 50–60 hr cultivation in the fermenter and it amounted to approximately 5.5–6 g/liter of fermentation broth. The medium contained initially 2% (v/v) kerosene as a carbon source. The maximum yield obtained corresponds to 37–40% (w/w) of kerosene supplied. At the same time the cell concentration was 10–13 g/liter which represents the yield of 67–87% (w/w). The rate of polymer production in the exponential phase was 0.25 g/liter hr and cell production rate was 0.27 g/liter hr. Sodium nitrate, 0.5%, and yeast extract, 0.3%, (w/w) were the best nigrogen sources for polymer formation. The highest level of polymer produced in broth was

ISSN:0006-3592    

DOI:10.1002/bit.260140309

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractStudies were performed using pure cultures ofA. acrogenesandE. coliand a heterogeneous microbial population growing in carbon‐limited chemostats with glucose as the sole carbon and energy source. A two‐level factorial experimental design was employed to test the hypothesis that the concentration of growth‐limiting substrate in a chemostat is controlled by the growth rate alone and is independent of the concentration of substrate entering the reactor. The pure culture experiments showed that the conclusions depend upon the measurement employed for growth‐limiting substrate. When the concentration of glucose was measured directly, the hypothesis was found to be true within the limits of the study (500–1500 mg/liter). However, if the chemical oxygen demand (COD) test was used as the measure of growth‐limiting substrate the hypothesis was found to be false. When heterogeneous cultures were employed the hypothesis was false regardless of the technique used to measure the concentration of growth‐limiting substrate. Nevertheless, it was possible to generate regression equations which described the interactions among influent COD, growth rate, and effluent COD with a high level o

ISSN:0006-3592    

DOI:10.1002/bit.260140310

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractPresently empirical expressions, especially the Monod equation, are used to quantitatively relate microbial growth rate to limiting substrate concentration in the solution. In this paper microbial growth is postulated to occur by a mechanism involving a mass transfer or assimilation process. The assimilation process is assumed to be substrate mass transfer limited and hence proportional to the limiting substrate concentration. The ingestion is assumed independent of limiting substrate concentration and only dependent upon internal reaction rates. The quantitative relationship between limiting substrate and microbial growth rate resulting from this mechanism is developed. Under certain limiting conditions this expression is shown to reduce to the Monod equation and under other conditions it reduces to the Lotka‐Volterra relationship. This mechanism is applied to batch and continuous cultures and the results obtained are compared quantitatively with experimen

ISSN:0006-3592    

DOI:10.1002/bit.260140311

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY