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A new inositol glycoside, 1 d -2-O-α- d - galactopyranosyl -chiro- inositol has been isolated from jojoba plant, Simmondsia chinensis.

Fractionation of the deacetylated acetolyzate of the borate-soluble fraction of the dextran elaborated by Leuconostoc mesenteroides NRRL B-1299 gave, after chromatography on charcoal—Celite, preparative paper-chromatography, and paper electrophoresis, four trisaccharide fractions and four tetrasaccharide fractions. The isolated oligosaccharides were characterized by their paper-chromatographic mobility, examination of partial acid-hydrolyzates of the oligosaccharides and their corresponding alditols, and methylation analysis. These oligosaccharides were shown to be ( a ) kojitriose ( 1 ), ( b ) isomaltotriose ( 2 ), ( c ) a mixture of 2- O -α-isomaltosyl- D -glucose ( 3 ), 2 1 - O -α- D -glucosylisomaltose ( 4 ), and 2- O -α-nigerosyl- D -glucose ( 5 ), ( d ) 6- O -α-kojibiosyI- D -glucose ( 6 ), ( e ) isomaltotetraose ( 7 ), ( f ) a mixture of 2- O -α-isomaltotriosyl- D -glucose ( 8 ) and 2 1 - O -α- D -glucosylisomaltotriose ( 9 ), ( g ) 6- O -α-kojitriosul- D -glucose ( 10 ), and ( h ) 6 3 - O -α- D -glucosylkojitriose ( 11 ), respectively. Some of these oligosaccharides are newly isolated and characterized.

Naegeli amylodextrin is the insoluble residue remaining after prolonged treatment of native starch granules with strong aqueous acid. The Naegeli amylodextrin from waxy maize starch was separated by gel chromatography on Sephadex G-50 into three fractions. Although the fractions were heterogeneous, their average structures were examined by enzymic degradation with porcine-pancreactic alpha amylase, beta-amylase, and pullulanase. The results show that Fraction I (highest molecular weight) has complex branching, Fraction II (major component, d.p. ∼25) contains about one branch per molecule, and Fraction III (d.p. ∼12) is mostly linear. Formation of these acid-resistant fractions may be explained as arising from a cluster model of amylopectin in which the outer chains are in a double-helical, crystalline arrangement.

Successive extraction of rice hull with hot water, 0.5% ammonium oxalate, 4% potassium hydroxide, and 24% potassium hydroxide, followed by neutralization of the alkaline extracts, yielded seven polysaccharide fractions. An electrophoretically homogeneous arabinoxylan was obtained as a precipitate (HC-IA) after neutralization of the 4% potassium hydroxide extract. The homogeneity of the rice-hull arabinoxylan was confirmed by ultracentrifugation, and by gel filtration through Sepharose CL-6B. It contained a small proportion of uronic acid (1.5%) and, on complete hydrolysis with acid, gave xylose and arabinose in the ratio of ∼19:1. This value is in close agreement with those calculated from the results of methylation analysis, and fragmentation analysis with endo-(1→4)-β- d -xylanase. The results from the methylation analysis, and from fragmentation analyses with acid and with endo-(1→4)-β- d -xylanase, indicated that the repeating unit of this arabinoxylan consists of a linear chain of 19 (1→4)-linked, β- d -xylosyl residues and an arabinofuranosyl side-chain joined through a (1→3) linkage.

Nageli amylodextrins were prepared from various types of starch (waxy maize, sweet potato, and potato) by prolonged treatment of the granules with 15% sulfuric acid. Each product was separated, by gel filtration on a column of Bio-Gel P-6, into two fractions, which were purified by repeated gel-filtration on the same column. The fraction having the lower molecular weight (d.p. 15–18, Fraction III) was completely hydrolyzed by beta amylase, regardless of the origin of the starch, suggesting that this product has a linear structure. The λ max value of the iodine complex of Fraction III from waxy-maize amylodextrin was, however, smaller than those of the counterparts from other origins. This result suggests that the chain length of Fraction III from the waxy-maize amylodextrin is slightly shorter than those of the others. The elution profiles of the amylodextrins, as well as those of their betaamylolysis products, were different from each other. These results, and the different iodine-staining activities of the amylodextrins or their fractions of higher molecular weight (d.p. 30–33, Fraction II), suggest that the structural features of the fractions differ from each other.

Extraction of rice bran with hot water, followed by removal of protein and starch, yielded a proteoglycan. Successive fractionation of this proteoglycan by salting out with ammonium sulfate and by DEAE-Sephadex column chromatography yielded several fractions shown to be homogeneous by disc electrophoresis. Treatment of the fractions with alkali and a proteolytic enzyme has shown that the polysaccharide and protein of the proteoglycan are most probably linked through an O -glycosyl linkage through hydroxyproline.

Rice hull was successively extracted with hot water (giving PS-I), 0.5% ammonium oxalate (PS-II), 4% potassium hydroxide (HC-I), and 24% potassium hydroxide (HC-II). By neutralization of the second alkaline extract, fraction HC-II was fractionated into subfractions HC-IIA (precipitated) and HC-IIB (not precipitated). To remove a xylan-like polysaccharide that contaminated HC-IIB, the fraction was treated twice with Streptomyces sp. endo-(1→4)-β-d-xylanase. Treatment of the xyloglucan-rich fraction from rice hull with partially purified Trichoderma viride cellulsae, followed by gel filtration on Bio-Gel P-2, yielded seven saccharide fractions, I–VII (Vo). Fractions III, IV, and V, the main oligosaccharides derived from the xyloglucan, were purified by repeated gel-filtration on Bio-Gel P-2, and preparative paper chromatography. The structures of III, IV, and V were examined by determination of the molar ratio of component monosaccharides and of the degree of polymerization, methylation analysis, and hydrolysis with partially purified β-d-glucosidase from Aspergillus oryzae and purified α-d-xylosidase from Aspergillus niger. The structures of III, IV, and V were characterized as follows. The structure of the xyloglucan of rice hulls was shown to be similar to those of xyloglucans in the cell walls of rice seedlings and barley seedlings.

Repeated digestion of the proteoglycan B from rice bran with Pronase and hemicellulase yielded two types of glycopeptides. The first group, obtained from the third enzymic digest, was a type of low molecular-weight glycopeptide and was fractionated into two subfractions by paper electrophoresis. The second group, obtained from the fourth enzymic digest, was a mixture of glycopeptides of relatively high molecular-weight and was fractionated into three subfractions by gel filtration on Sephadex G-75. Alkaline degradation of these glycopeptides or the intact proteoglycan A yielded a sugar-amino acid compound, whose structure was established as O-alpha-L-arabinofuranosyl-hydroxyproline. These results indicate that the carbohydrate-protein linkage of the rice-bran proteoglycan is an O-glycosyl linkage between L-arabinose and hydroxyproline.