Biosynthesis and profiles of fatty acids, vitamin E and carotenoids during flax (Linum usitatissimum L.) seed capsule maturation

Abstract

This study investigated the profiles of major fatty acids, vitamin E and carotenoids at metabolic and transcription levels in fibre flaxseed capsule at six mature stages. From 5 days after flowering (DAF) to 15 DAF, the percentages of a-linolenic acid and oleic acid notably increased, whereas palmitic acid and linoleic acid dramatically decreased, and finally remained stable till S6. The content of c-tocopherol was progressively raised to the maximum at the last stage, while a-tocopherol presented a gradually declining trend from 5 DAF to 40 DAF. The total carotenoids in flaxseed capsules decreased continuously, and lutein remained the abundant one throughout the maturation. The varied expression pattern of genes in fatty acid, vitamin E and carotenoid biosynthetic pathway could partly explain the changes of these components during flaxseed capsule maturation. These results suggested fibre flaxseed capsules could be an attractive source of liposoluble compounds for further food and nutraceutical applications.

Key FAD2, FAD3, and SAD Genes Involved in the Fatty Acid Synthesis in Flax Identified Based on Genomic and Transcriptomic Data

“…You et al suggested that FAD2a-1/FAD2a-2, FAD2b-1/FAD2b-2, and FAD3a/FAD3b play a crucial role in the synthesis of linseed oil FAs [46]. The same role of these genes was also demonstrated in other studies [44,[48][49][50].…”

Exogenously applied 5-aminolevulinic acid modulates growth, yield, and physiological parameters in lentil (Lens culinaris Medik.) under rain-fed and supplemental irrigation conditions

“…However, exogenous ALA can reduce the accumulation of ROS and maintain the stability of the chloroplast membrane under stress environments. In addition, ALA inhibits chlorophyll synthesis by reducing the level of Mg-chelatase and Protochlorophyllide oxidoreductase 41 . The higher concentration (5–40 mM) of ALA led to the accumulation of several chlorophyll intermediaries in plants, such as protochlorophyllide, protoporphyrin IX, and protoporphyrin magnesium 42 .…”

“…Studies have shown that water stress reduces the amount of carotenoids in plants 44 . ALA application enhances carotenoid biosynthesis by positively regulating enzymes such as geranylgeranyl diphosphate synthase, phytoene synthase, phytoene desaturase, and lycopene β-cyclase 41 . In addition, ALA application has been found to increase the content of carotenoids, as well as improve chlorophyll a, chlorophyll b, and total chlorophyll, as demonstrated in another study 45 .…”

“…However, exogenous ALA can reduce the accumulation of ROS and maintain the stability of the chloroplast membrane under stress environments. In addition, ALA inhibits chlorophyll synthesis by reducing the level of Mg-chelatase and Protochlorophyllide oxidoreductase 41 .…”