The effect of high-pressure processing (HPP) on cell wall polysaccharides in berries was investigated. HPP decreased the degree of methyl esterification (DM), probably by activation of pectin methyl esterase (PME), and improved the extractability of pectins. When commercial enzyme mixtures were added to mashed berries, a synergistic effect was observed between treatment with commercial enzymes ...

As the result of recent researches our knowledge of the pectic substances of plants has become more systematic, and it is proposed in the present paper to adhere to the nomenclature adopted by the American Pectin Symposium of 1925. Thus we are now acquainted with protopectin, the naturally occurring pectic substance; pectin, the substance extracted from the plant by chemical or other means with...

Branfoot (1) has summarised the early work on pectic substances. Bonner (2), Norman (3), and Hirst and Jones (4) have reviewed later work on the structure of these substances. Pectic materials that approximate the composition and have some of the properties of pectic acid are widely distributed but in small amounts in mature hardwoods. In 1925 O’Dwyer (5) isolated such a material from beechwood...

Pectic fragments of cell wall polysaccharides, released from the walls of suspension-cultured sycamore cells by treatment with endopolygalacturonase, were tested for morphogenesis-regulating activity in a modified tobacco thin-cell-layer explant (TCL) bioassay (D. Mohnen, S. Eberhard, V. Marfa, N. Doubrava, P. Toubart, D. J. Gollin, T.A. Gruber, W. Nuri, P. Albersheim, and A. Darvill, manuscrip...

In the preceding paper (1) a method was described for the purification of the extracellular pectin trans-eliminase of Aspergillus jonsecaeus. The enzyme was purified by a three-step procedure to the point at which other pectic enzymes and cellulase were no longer detectable. The effects of pH, of Na+, Mg++, and Ca++ ions, and of a few anions on the activity of the enzyme were also reported. In ...

Pectins are a group of plant polysaccharides whose principal component is 1,4-linked a-d-galactosyluronic acid (O’Neill et al., 1990). Pectins are present in the primary cell walls of all seed-bearing plants and in the junction between cells called the middle lamella. The primary wall surrounds growing plant cells, meristematic cells and cells in succulent tissue such as fruit. The secondary wa...

This study aimed at understanding softening in Jonagold apple (Malus×domestica Borkh.) fruits, by investigating pectin modifications and the evolution of pectin-modifying enzymes during postharvest storage and ripening. Jonagold apples were harvested at commercial maturity and stored at different temperatures and controlled atmosphere conditions for 6 months, followed by exposure to ambient she...

A large number of bacteria and fungi secrete extracellularly the enzyme complex often termed 'pectinase', which causes the rapid disintegration of plant tissue and is consideredtheprimaryinstrument of the attack on plant tissues by these microorganisms. The action of pectinase on a solution of pectin results in the following changes: (a) a rapid lowering of the viscosity of the solution; (b) a ...