Changes in pH, Carbonate and Lactate of the Blood of Yearling Kamloops Trout, Salmo gairdneri, During and Following Severe Muscular Activity

1959 ◽  
Vol 16 (4) ◽  
pp. 391-402 ◽  
Author(s):  
Edgar C. Black ◽  
Wing-gay Chiu ◽  
Francis D. Forbes ◽  
Arthur Hanslip
Keyword(s):  
Marked Decrease ◽  
Initial Level ◽  
Muscular Activity ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Salmo Gairdneri ◽  
Blood Levels ◽  
Hydrogen Ion Concentration ◽  
Initial Rise ◽  
Initial Figure

Alterations in the blood levels of lactate, carbonate, hydrogen ion and hemoglobin following vigorous muscular exercise were studied in yearling Kamloops trout, Salmo gairdneri, over four years.Lactate increased during exercise and during the first 2 hours of rest, returning to the initial level after 6 to 8 hours. Carbonate increased to a maximum during the first 3 minutes of exercise, then dropped precipitously to a minimum far below the initial level after [Formula: see text] hour of rest, later rose to near the initial level at the 4th hour of recovery, maintained this until the 12th hour, but it had decreased again at the 24th hour. Hydrogen ion concentration rose sharply during the first 3 minutes of activity, then fell off to a stable level a little above the initial figure until the end of exercise, after which it fell substantially below initial level and had not completely recovered after 24 hours of rest. A marked decrease in swimming rate occurred after 3 minutes exercise, following the initial rise of carbonate and hydrogen ion concentration.

PREPARATION AND HEAT DENATURATION OF THE GLUTEN PROTEINS

1931 ◽  
Vol 5 (4) ◽  
pp. 389-406 ◽  
Author(s):  
W. H. Cook
Keyword(s):  
Elevated Temperatures ◽  
Marked Decrease ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Heat Denaturation ◽  
Hydrogen Ion Concentration ◽  
Gluten Proteins ◽  
Buffer Solutions ◽  
Natural Moisture Content ◽  
Low Solubility

Gliadin prepared by several different methods had the same nitrogen content and distribution. The critical peptization temperature (C.P.T.) in 60% alcohol and viscosity in 30% urea-buffer solutions, however, showed considerable variation, preparations of high C.P.T. (low solubility) being more viscous. This variation in the physical properties is explained by fractionation or denaturation incidental to the method of preparation.Gluten precipitated from 30% urea solutions at salt concentrations varying from 0.1 to 0.5 of saturation, yielded fractions that varied continuously in their gliadin and glutenin content, as judged from their percentage of arginine nitrogen.Gluten dispersed in buffered 30% urea solutions showed no change in viscosity during 101 hr. after the gluten was completely dispersed. A variation of hydrogen ion concentration between pH 6.0 and 6.95 had little effect on its viscosity. Heating at 70 °C. caused a marked decrease in the viscosity of this dispersion during the first hour. When gliadin dispersions are heated as above only samples having a high initial viscosity and C.P.T. become less viscous. Heating gliadin of natural moisture content (12 to 14%) at 70 °C. for varying periods of time did not change significantly its subsequent C.P.T. and viscosity in 60% alcohol. More severe heat treatments at higher moisture contents rendered the gliadin insoluble in 60% alcohol. Dilute alcoholic extracts of heated flours contained less protein than those of unheated controls. However, the C.P.T. of the former was lower than that of the latter. It is concluded from these experiments that when the gluten proteins are subjected to elevated temperatures, the glutenin fraction is first affected, next the gliadin fractions of low solubility, and finally, under severe conditions, all of the gliadin is denatured.

Sign in / Sign up

Export Citation Format

Share Document