Lara-Núñez A, Díaz-Pontones DM

Language: Spanish
References: 17
Page: 109-115
PDF size: 273.98 Kb.

ABSTRACT

Some groups of angiosperm seeds store reserve materials at the cell wall. Among those are hemicelluloses, which comprise xyloglucans, galactans and mannans. The latter are constituted by a mannose backbone that could be interrupted by glucose and substituted by galactose. Mannans are classified into four varieties depending on its composition and substitution grade, and either could exert osmotic control during germination or confer seed coat´s hardness. Seeds that accumulate reserve material at the cell wall are palm, tamarind, date, lettuce, tomato and seeds from the genus Ipomoea (Morning Glory). At the end of germination mannan degradation starts through a set of hydrolytic enzymes, and once monomers are freed, they could be channeled to carbon central metabolism or could be precursors of cell wall de novo synthesis. Galatomannans are used in the food and pharmaceutical industry as well as in the mining and tobacco industry, among others.

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