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Biomedical subjects

G Finne

Publications and source records attributed to G Finne.

6 recordsLinked to original sources
PubMed1981

Modified colorimetric method for determining indole in shrimp.

A modified spectrophotometric method for measuring indole in shrimp is described. The method was developed to eliminate the time-consuming steam distillation and expensive instrumentation required by the official AOAC methods. Indole is extracted with light petroleum from trichloroacetic acid-precipitated shrimp muscle. The extracted indole, soluble in light petroleum, is reacted and re-extracted with Ehrlich's reagent; indole in the form of a rose indole complex can be determined spectrophotometrically. When shrimp at various degrees of decomposition were analyzed for indole by the modified method as well as by the official AOAC colorimetric method, the correlation coefficient between the data from the 2 methods was 0.98.

Animals↗
PubMed1976

Spin-labeling studies on the lipids of psychrophilic, psychrotrophic, and mesophilic clostridia.

Spin-labeling studies were conducted to elucidate the viscosity and phase transition temperatures of lipids isolated from psychrophilic, psychrotrophic, and mesophilic clostridia. Electron spin resonance spectroscopy indicated that the lipids, for all the growth temperatures tested, were in a fluid state and from 13 to 24 C higher than the corresponding lipid transition temperatures. When the organisms were grown at different temperatures, a psychrotropic and two mesophilic clostridia were shown to be able to adjust their lipid-phase transition temperature to the growth temperature. A psychrophilic Clostridium strain, when grown at different temperatures, synthesized lipids that had the same phase transition temperature. It is suggested that this lack of growth temperature-inducible regulation of lipid-phase transition temperature may be a molecular determinant for the psychrophily of this organism. It is proposed that the growth temperature range of an organism is dependent upon the ability of the organism to regulate its lipid fluidity within a specific range.

Clostridium↗
PubMed1976

Phosphorus pentoxide as a drying agent for bacterial culture extracts analyzed by gas-liquid chromatography.

The procedure for gas chromatographic analysis of metabolic products of microbial fermentation includes solvent extraction of the aqueous growth media, drying of the extract, and direct chromatographic analysis of the solvent. In this study, 2 drying agents, magnesium sulfate and phosphorus pentoxide, were compared. Both were effective in removing water; however, phosphorus pentoxide removed water more completely and at a faster rate than magnesium sulfate. When a thermal conductivity detector is used, it is important to completely remove water from the solvent to prevent interference with volatile acids and alcohols. When water is present, short-chain alcohols (C2-C5) are eluted together with the water, causing peak overlap and shoulder separations. Phosphorus pentoxide quickly and effectively removed water so that a baseline was established following the solvent front on the chromatogram. The use of phosphorus pentoxide is particularly advantageous for identification or fermentation studies on Clostridium and Propionibacterium when rapid identification is desired or when large numbers of cultures are to be tested.

Chromatography, Gas↗
PubMed1975

A comparative study on the heat stability of triosephosphate isomerase in psychrophilic, psychrotrophic, and mesophilic clostridia.

The temperature stability of triosephosphate isomerase (EC 5.3.1.1) in the cell-free extracts of psychrophilic, psychrotrophic, and mesophilic Clostridium species has been investigated. Even though this enzyme was found to be heat labile in the psychrophilic isolates, no detectable loss in activity was evident when cell-free extracts were heated for 1/2 h at the maximum temperature of growth for the organisms. Two organisms, each with a maximum growth temperature of 23 degrees C, showed different heat stability of triosephosphate isomerase. However, a trend is evident that as the maximum growth temperature increases, the thermostability also increases. It is suggested that the heat liability of this enzyme is not a controlling factor in psychrophilism, but rather an adaptation to the cold habitat of these organisms.

Adaptation, Physiological↗