Abstract
Twentyβone Monocotyledon and 59 Dicotyledon seed samples, nine pollen samples and 12 fractions of seeds were analysed for their content of dry matter, total nitrogen and glycoprotein and total hexosamine. An estimate was made of the frequency of occurrence of hexosamine in the proteins of the samples. The dry matter contents (as g per 100 g sample) showed little variation (88.0β95.1, seeds and 84.1β90.9, pollens). The total nitrogen contents (as g per 100 g sample) varied from 0.84β3.29 (Monocotyledons), 1.42β7.13 (Dicotyledons) and 2.91β5.43 (pollens). The glycoprotein hexosamine content (as mmol per 100 g sample) varied from 0.078β0.32 (Monocotyledons), 0.11β0.73 (Dicotyledons) and 0.36β0.78 (pollens). The frequency of occurrence of hexosamine in the proteins (as hexosamine residues:amino acid residues) varied from 1:450 to 1:1940 (Monocotyledons), 1:300 to 1:3640 (Dicotyledons) and 1:330 to 1:760 (pollens). The decomposition of hexosamines during prolonged acid hydrolysis prevented accurate estimates of nonβprotein hexosamine contents being obtained but the results indicated that they varied from a few percent of, to about equal to, the contents of glycoprotein hexosamine in the samples examined.