LIPID AND PROTEIN IN GERMINATING AND DEVELOPING FLAXSEED LINUM USITATISSIMUM L.

Abstract

The metabolism of lipid and protein fractions in developing and germinating flaxseed was investigated. Fatty acid concentrations in the early-development stages of field- and greenhouse-grown plants showed similar increases, but the fatty acid composition of the mature seed appeared to be influenced by environment. The pattern of fatty acid interconversions during lipid synthesis suggested that more-unsaturated acids were formed from less-unsaturated ones. Studies at later stages of seed development indicated that the lipid was in a state of dynamic equilibrium. The relative proportions of each fatty acid during germination remained constant, suggesting that fatty acids were being broken down at a rate proportional to the amount originally present. During flaxseed development protein content increased steadily. Until 4 weeks after the plants had bloomed, the total content of each amino acid increased, but the free amino acid portion and amide nitrogen decreased. Subsequently all remained at a constant level. During germination the protein content and the proportions of the various amino acids of flaxseed remained constant but the free amino acid content rose. The radioisotope studies gave no clear indication of amino acid interconversions.