Dynamics of fatty-acid composition of neutral acylglycerols in maturing euonymus fruits.
The dynamics of the fatty-acid (FA) composition of neutral acylglycerols (NAGs) composed of 1,2,3-triacyl-sn-glycerols (TAGs) and 3-acetyl-1,2-diacyl-sn-glycerols (acDAGs) was determined in the fruit seeds and arils of three Euonymus L. species at three stages of their maturity. The NAG composition comprised 29 FAs, linoleic, oleic, palmitic, and α-linolenic acids being predominant. Noticeable amounts of other FAs, such as lauric, myristic, hexadec-9-enoic, stearic, (Z)-vaccenic, and arachidic acid, etc., could also be present. In the course of maturation, the qualitative composition of major FAs remained nearly unchanged, while the unsaturation index of FAs in seeds and in TAGs, as well as, but to a lesser extent, in arils and in acDAGs, respectively, always decreased. This decline was brought about by a sharp fall of the α-linolenate level, a decrease of the linoleate content, and a corresponding rise in the oleate content. It is suggested that, in both seeds and arils, both classes of NAGs were formed at the expense of the same FA pool; the quantitative composition of this pool was characteristic of a given fruit part and strongly changed during maturation. The accumulation of TAGs in E. europaeus fruits was accompanied by a conversion of hexadec-9-enoic acid into (Z)-vaccenic acid via the C2 -elongation reaction.
Laboratory of Lipid Metabolism, K. A. Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya ul. 35, Moscow 127276, Russia, (phone: +7-499-9778355; fax: +7-499-9778018).
Roman A
RA
Sidorov
Anatoly V
AV
Zhukov
Vasily P
VP
Pchelkin
Andrei G
AG
Vereshchagin
Vladimir D
VD
Tsydendambaev
D029756:Euonymus / Q000737:chemistry*; D005227:Fatty Acids / Q000032:analysis* / Q000737:chemistry; D005638:Fruit / Q000737:chemistry* / Q000254:growth & development* / Q000378:metabolism; D005989:Glycerides / Q000737:chemistry*; D009829:Oleic Acids / Q000378:metabolism; D012639:Seeds / Q000737:chemistry; D014280:Triglycerides / Q000378:metabolism; D017962:alpha-Linolenic Acid / Q000032:analysis
D005227:Fatty Acids; D005989:Glycerides; D009829:Oleic Acids; D014280:Triglycerides; D017962:alpha-Linolenic Acid; C050413:11-octadecenoic acid
Euonymus species; Fatty acids; Neutral acylglycerols (NAGs)