ABSTRACT
The main carbohydrates include sucrosyl-oligosaccharides, alditols and mannitol, cyclitols, and monosaccharide such as glucose, fructose, and sedoheptulose. Galactosyl-sucrose oligosaccharides are synthesized by sequential actions of α-galaetosyltransferases. Planteose is the only galactosyl-sucrose which is strictly limited in its occurrence to seeds, where it acts as a reserve carbohydrate and possibly also as a desiccation protectant. The model states that raffinose and stachyose are made in the phloem's intermediary cells from sucrose, which is made in the mesophyll and diffuses to the intermediary cells symplastically. Quantitative analysis of galactosyl-sucrose oligosaccharides commonly involves extraction, desalting, and chromatographic separation. Chromatographic separation of purified extracts containing galactosyl-sucrose oligosaccharides has traditionally been achieved by one- or two-dimensional paper chromatography. The capacity of tissues to assimilate galactose is not restricted to germinating seeds or to sink tissues of plants that translocate raffinose family of oligosaccharides (RFO) as photosynthetic products. An interesting feature of RFO plants is the complex compartmentation of RFO synthesis within their source leaves.
