Of raffinose

D-galactose, C HiiOe. Crystallizes in the pyranose form m.p. 1I8-120 C (monohydrate), 165-5" C (anhydrous). An isomer of glucose which is fairly widely distributed in plants. It is a constituent of raffinose and slachyose, of hemicelluloses, of pectin, of gums and mucilages, and of some glycosides. In animals it forms half the lactose molecule and is the sugar found in the brain. Chemically it is very similar to glucose. It has the structure... 

The non-reducing disaccharide unit of raffinose and gentianose is certainly sucrose, as previously mentioned in the case of melezitose all that can be said with assurance at the present time is that this sugar is 8-[a-T>-glucopyrano8yl2-(f)-T>-fructofuranosyl-a-j)-glucopyranoside. It would indeed be surprising, from biological views, if the now unknown disaccharide component should eventually prove to be other than sucrose,... 

The reaction of these aldehydes, derived from periodate oxidation, with carbonyl reagents has also been investigated. Studies 147 148 were made on oxidized laminarin, a (1 —> 3)-linked polysaccharide, in which only the terminal residues had been oxidized. The addition of phenylhydrazine acetate detached the remainder of the terminal residue as glyoxal phenyl-osazone. When the aldehydic compounds derived from the periodate oxidation of raffinose and trehalose818a were reacted with p-nitrophenylhydrazine, the authors were surprised to find that one molecule of oxidized raffinose, containing six aldehydic functions, reacts with only three molecules of the reagent, and that the four aldehydic functions of the oxidized trehalose molecule react with only two. The reactions of periodate-oxidized carbo-... 

Figure 5. Morphology of sucrose crystal grown in pure solution (b) and in the presence of raffinose (a) 100 projection.

Thippeswamy, S. and Mulimani, V.H., Enzymic degradation of raffinose family oligosaccharides in soymilk by immobilized alpha-galactosidase from Gibberella fujikuroi, Proc. Biochem., 38 (2002) 635-640. 

SCHEME 29. Mohamed A. Salam s initial work on the selective chlorination of raffinose (1979). 

L. Hough, A. C. Richardson, and M. A. Salam, Reaction of raffinose with sulphuryl chloride, Carbohydr. Res.,11 (1979) 85-93. 

Figure 4.2.2 depicts the urinary oligosaccharide patterns of sialidosis (a-neur-aminidase deficiency), GM1 gangliosidosis and mucopolysaccharidosis type IVB (/3-galaclosidase deficiency) compared to a normal urine and standards of raffinose, lactose and glucose. In patients with sialidosis, a densely staining band close to the... 

Hydrolysis and Utilization of Raffinose by Cultures of Saccharomyces uvarum of Various Genotypes198... 

Table VI instances eight possible gene combinations affecting the utilization of raffinose. Correspondingly, yeasts of different species utilize different parts of the raffinose molecule199 or none Barnett4 exemplified each kind of utilization for species of Saccharomyces described by van der Walt.92...

The Anaerobic Utilization of Sucrose by 137 Species That Ferment D-Glucose and Use Sucrose Aerobically Association with Utilization of Raffinose"... 

Considering these problems, we tested a computer extrapolation (6) for sucrose, shown in the conformation maps in Figure 4. Four sets of crystal parameters were used, those from the structure of sucrose (S) (45) and those from the sucrose component of raffinose pentahydrate... 

Raffinose hendecanitrate, Ci8H2i05(0N02)ii, from the nitration of raffinose,69 exists in the form of amorphous aggregates which melt at 55-65° and decompose at 136°. It reduces Fehling s solution on warming. It decomposes rapidly when kept at 50°. 

Very successful experiments were carried out on the oxidation of sucrose, one mole of which needs three moles of periodic acid, with the formation of one mole each of formic acid and a tetraaldehyde. The latter is oxidized by bromine to a tetracarboxylic acid subsequent acid hydrolysis of the oxygen bridges affords a mixture of acids, all of which were isolated and identified. These results brought in 1943 a confirmation of the structure of sucrose which was discussed, and which gained the approval of C. S. Hudson who, before that, was a little doubtful about the furanoid form of the D-fructosyl group. Similar work was done later with trehalose. In the same way, J. . Courtois obtained confirmation of the structure of raffinose, and established that of stachyose. 

Determination of Saccharose, Raffinose and a Reducing Sugar together.—If the same notation as before is used and a represent the rotation due to 1 gram of the inversion products of raffinose, the following three equations hold ... 

Since the methylation analysis of raffinose by Haworth and coworkers,114 the structure assigned (4) has been confirmed by chemical and enzymic methods.115... 

Raffinose occurs only at low concentrations in the leaves of plants, but accumulates in the storage organs during the process of development. It has been generally observed that the level of raffinose increases as the tissue loses water this 108-1i3,u6-m js a characteristic feature of maturation of seeds and the hardening process of winter-hardy plants. The hardiness of several plants towards desiccation and elevated temperature may be compared to the property of frost resistance.125-134 When the heat resistance reaches a maximum in the summer, the frost resistance is at its minimum. 

Rafflnose was shown to have a detrimental effect in the manufacture of sucrose. Sugar beets contain a small proportion ( 0.05%) of raffinose and a sucrose content of 16%. Sugar beets serve as the main... 

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