Arabinosyl residues decreased 49% in WSP and may be correlated to a decrease in arabinan degradation (Fig. 2). Xylose and galactose contents also decreased in the WSP (44% and 56%, respectively), suggesting xyloglucan (XG) and xylogalacturonan (XGA) insolubilization (Fig. 2). Mannose content, in turn, was higher in WSP of aged seeds (41%), probably caused due to the decrease in pectin and ratios, since the extraction enzymes are mannose-rich (Fig. 2). Hence, the identification of neutral and acidic polysaccharides of WSP as well as their ratio may reveal which cell wall component had become less soluble due to aging. Anion exchange chromatography. The WSP anion exchange chromatography produced two peaks, one composed mainly of neutral pectins (Pool 1) and another containing mostly acidic pectins (Pool 2) (Fig. 3). The proximate areas under Pools 1 and 2 of aged and soft seeds were calculated and its ratios (area of Pool 2/area of Pool 1) calculated. The results revealed that in aged seed WSP elution profile
there was an increase in the area under Pool 2 and a shift of the secompounds to a more acidic regions. This indicates an increase of acidic polymers in the WSP of aged seeds (Fig. 3). The monosaccharide compositions of both fractions (Pools 1 and 2) are consisten twith an increase of acidic polymers in the WSP of aged seeds (Fig. 4).