Electrophoretic Analysis of Ruminal Degradability of Corn Proteins
Open Access
- 1 April 1994
- journal article
- Published by American Dairy Science Association in Journal of Dairy Science
- Vol. 77 (4), 1093-1099
- https://doi.org/10.3168/jds.s0022-0302(94)77044-2
Abstract
Albumin, globulin, and prolamin fractions were extracted from corn meal in water, .5 M NaCl, and 50% (vol/vol) 1-propanol and examined by SDS-PAGE and densitometric scanning to investigate fractional degradation rates of corn proteins. Several protein fractions were identified for globulins, zein prolamins, and glutelins. Ruminal degradability of individual subfractions was evaluated by suspension of corn and corn gluten meal samples in the rumen of lactating dairy cows from 0 to 72 h. Electrophoretic and densitometric analysis of protein residues revealed that the prolamin fraction zein for corn and corn gluten meal was more resistant to ruminal degradation than albumins, globulins, and glutelins. Relative rates of degradation of zein and the fraction containing albumins, globulins, and glutelins were .060, .026, and .018, .015/h for corn and corn gluten meal, respectively. Total degradabilities of corn and corn gluten meal, measured by summation of degradability of subfractional components, were 52.2 and 18.6%. Quantitative measurement of ruminally degradable subfractions and estimation of their degradation rates by electrophoretic and densitometric scanning are useful in understanding ruminal degradability of corn proteins.Keywords
This publication has 9 references indexed in Scilit:
- Comparison of Fibrous Materials as Modifiers of In Situ Ruminal Degradation of Corn Gluten MealJournal of Dairy Science, 1993
- Degradability of Soybean Meal Protein Fractions as Determined by Sodium Dodecyl Sulfate-Polyacrylamide Gel ElectrophoresisJournal of Dairy Science, 1990
- Ruminant Nitrogen UsagePublished by The National Academies Press ,1985
- Physicochemical properties of maize glutelins as influenced by their isolation conditionsJournal of Agricultural and Food Chemistry, 1981
- A revised model for the estimation of protein degradability in the rumenThe Journal of Agricultural Science, 1981
- The estimation of protein degradability in the rumen from incubation measurements weighted according to rate of passageThe Journal of Agricultural Science, 1979
- In Vitro Procedures for Estimating Rates of Ruminal Protein Degradation and Proportions of Protein Escaping the Rumen UndegradedJournal of Nutrition, 1978
- Biochemical basis for the differences in plant protein utilizationJournal of Agricultural and Food Chemistry, 1974
- Cleavage of Structural Proteins during the Assembly of the Head of Bacteriophage T4Nature, 1970