Galactolipids are a type of

glycolipid Glycolipids are lipids with a carbohydrate attached by a glycosidic (covalent) bond. Their role is to maintain the stability of the cell membrane and to facilitate cellular recognition, which is crucial to the immune response and in the connec ...

whose sugar group is galactose. They differ from glycosphingolipids in that they do not have nitrogen in their composition. They are the main part of plant membrane lipids where they substitute phospholipids to conserve phosphate for other essential processes. These chloroplast membranes contain a high quantity of monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG). They probably also assume a direct role in photosynthesis, as they have been found in the X-ray structures of photosynthetic complexes. Galactolipids are more bioavailable than free fatty acids, and have been shown to exhibit COX mediated anti-inflammatory activity. Bio-guided fractionation of spinach leaves (''Spinacia oleracea'') revealed alpha-linolenic acid galactolipids (18:3, n-3) were responsible for inhibitory effects on tumor promoter-induced Epstein-Barr virus (EBV) activation. Recently, it has been demonstrated that this same galactolipid, 1,2-di-O-α-linolenoyl-3-O-α-D-galactopyranosyl-''sn''-glycerol, may be important for the anti-inflammatory activity of

Dog Rose ''Rosa canina'', commonly known as the dog rose, is a variable climbing, wild rose species native to Europe, northwest Africa, and western Asia. Description The dog rose is a deciduous shrub normally ranging in height from , though sometimes it ...

(''Rosa canina''), a medicinal plant with documented effect on inflammatory diseases such as arthritis. The galactosphingolipid galactocerebroside (GalC) and its sulfated derivative sulfatide is also in abundance present (together with a small group of proteins) in myelin, the membrane around the axons in the nervous system of vertebrates. It is galactolipids, rather than phlorotannins, that act as

herbivore A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...

deterrents in '' Fucus vesiculosus'' against the sea urchin '' Arbacia punctulata''.Galactolipids rather than phlorotannins as herbivore deterrents in the brown seaweed Fucus vesiculosus. Michael S. Deal, Mark E. Hay, Dean Wilson and William Fenical, Oecologia, June 2003, Volume 136, Issue 1, pages 107-114,

References

{{reflist Glycolipids Carbohydrate chemistry