HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Yaguchi, M. Articles by Tarassuk, N. P. Search for Related Content PubMed Articles by Yaguchi, M. Articles by Tarassuk, N. P.

Fractionation of Milk Proteins on Anion-Exchange Cellulose¹

Department of Dairy Industry, University of California, Davis

ABSTRACT

A method of column chromatography using anion-exehange cellulose was developed by Sober and Peterson (1,3) and successfully applied to various proteins, nucleic acids, and enzymes. They reported that the resolving power of the cellulose ion-exchanger is greater than that afforded by conventional electrophoresis. They recovered 50–100% of the activity of various enzymes and achieved quantitative nitrogen recovery (3).

An attempt was made to apply this technique in fractionating milk proteins. The procedure used was that described by Sober et al. (2) for preparing the adsorbent column and developing the chromatogram.

Freshly drawn, uncooled mUk from a single cow was separated into cream and skimmilk immediately after milking, and cooled rapidly with ice water. The skimmilk was dialyzed for 24 hr. against large amounts of the starting buffer (0.005 M sodium phosphate at pH 7.0) and the buffer was changed frequently. Twenty-five milliliters of the dialyzed skimmilk was placed on the column (anion-exchange adsorbents DEAE-SF², Diethylaminoethanol on Solfa-Floc cellulose lattice) and followed with continuous flow of buffer. Gradients of salt or pH or both were employed for elution. Toluene-covered sodium phosphate buffers were used at flow rates of about 50 ml. per hour (7 p.s.i. N₂). The elution diagram obtained is shown in Figure 1. The individual effluent fractions of about 5 ml. each were examined in a Beckman DU spectrophotometer at 280 mµ.

¹ This study was supported in part by funds from the California Dairy Industry Advisory Board.