AJCN EB Program 2010 Early Registration
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text (PDF)
Right arrow Purchase Article
Right arrow View Shopping Cart
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Leichter, J.
Right arrow Articles by Krumdieck, C. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Leichter, J.
Right arrow Articles by Krumdieck, C. L.
Agricola
Right arrow Articles by Leichter, J.
Right arrow Articles by Krumdieck, C. L.

American Journal of Clinical Nutrition, Vol 32, 92-95, Copyright © 1979 by The American Society for Clinical Nutrition, Inc

ORIGINAL RESEARCH COMMUNICATIONS

Folate conjugase activity in fresh vegetables and its effect on the determination of free folate content

J Leichter, AF Landymore and CL Krumdieck

The levels of naturally-occurring folate conjugates in fresh asparagus, broccoli, Brussels sprouts, cabbage, cauliflower lettuce, and spinach were determined together with the effect on the hydrolysis of pteroylpolyglutamates during the extraction phase of the Lactobacillus casei assay. The levels of conjugate activity vary widely among the vegetables tested, from a low of 0.30 +/- 0.21 in lettuce to a high of 106.2 +/- 6.6 mumoles/hr per 100 mg of fresh weight in spinach. The free folate values (L. casei activity before chicken pancreas conjugase treatment) in the fresh vegetables boiled 1 hr after homogenization were significantly higher than those in vegetables boiled before homogenization, while there were no significant differences in total folate (L. casei activity after treatment with conjugase from chicken pancreas). The increase in free folate values must have been due to the action of endogenous conjugases on the pteroylpolyglutamates from the time the vegetables were homogenized until the conjugase was inactivated by heat. It is concluded that reliable free folate values in fresh vegetables can be obtained only if the naturally present conjugases are inactivated before homogenization of sample in order to prevent the hydrolysis of the pteroylpolyglutamates in the vegetables.


This article has been cited by other articles:


Home page
 J. Biol. Chem.Home page
G. Orsomando, R. D. de la Garza, B. J. Green, M. Peng, P. A. Rea, T. J. Ryan, J. F. Gregory III, and A. D. Hanson
Plant {gamma}-Glutamyl Hydrolases and Folate Polyglutamates: CHARACTERIZATION, COMPARTMENTATION, AND CO-OCCURRENCE IN VACUOLES
J. Biol. Chem., August 12, 2005; 280(32): 28877 - 28884.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1979 by The American Society for Nutrition