This item still needs to be validated !
Title: Influence of beta-subunit on thermal and high-pressure process stability of tomato polygalacturonase
Authors: Peeters, L
Fachin, D
Smout, Chantal
Van Loey, Ann
Hendrickx, Marc #
Issue Date: 2004
Publisher: John wiley & sons inc
Series Title: Biotechnology and Bioengineering vol:86 issue:5 pages:543-549
Abstract: Polygalacturonase (PG; E.C. was extracted from tomato fruit and purified by cation-exchange chromatography. Two peaks containing PG activity were detected: the first denotes a thermolabile PG fraction (PG2) and the second a thermostable fraction (PG1). PG1 is a dimer of PG2 and a heat-stable protein called the p-subunit. In contrast to its resistance to heat, PG is easily inactivated at elevated pressure. Although the thermal stability of purified tomato PG1 and PG2 is distinctly different, they show an identical pressure stability. To gain further insight into the thermal and pressure stability of both PG isoenzymes, the in vitro recombination of PG2 and beta-subunit was studied. After severe heat (up to 140degreesC for 5 min) and pressure (up to 800 MPa for 15 min) treatments, the residual fractions containing the beta-subunit were able to convert PG2 into the heat-stable PG1, showing the extreme thermal and pressure stability of the -subunit. PG1 was detected in heat-treated tomato juice and, to a lesser extent, in tomato pieces. In contrast, as was the case for purified PG, no pressure-stable fraction was observed when tomato juice and pieces were treated under pressure. These data clearly show the differing behavior of the PG1-PG2-beta-subunit system under thermal and high-pressure treatments and offer the possibility of inactivating tomato PG using high pressure without the need for high temperatures. (C) 2004 Wiley Periodicals, Inc.
ISSN: 0006-3592
Publication status: published
KU Leuven publication type: IT
Appears in Collections:Centre for Food and Microbial Technology
# (joint) last author

Files in This Item:

There are no files associated with this item.

Request a copy


All items in Lirias are protected by copyright, with all rights reserved.

© Web of science