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Berteroa incana is a wild herb widespread in temperate zones which was practically not studied for its biological effects. Methanolic and aqueous extracts of B. incana were assessed for the content in polyphenols and the related antioxidant and antimicrobial activities and the polysaccharide extract for the content in saccharides and the associated cytostatic effect. The results obtained highlighted that the methanolic extracts of B. incana contain moderate amounts of polyphenols, the most representative been isoquercitrin 4.41 ± 0.02 mg100 g -1 dry weight plant material (DW), quercetin 4.21 ± 0.05, sinapic acid 5.23 ± 0.12 and ferulic acid 5.05 ± 0.12 mg 100 g -1 DW, with correlated moderate antioxidant activities (IC 50 13.40 ± 0.01 μg mL -1 ) and absent antibacterial activity. The polysaccharide fraction showed high content in saccharides, especially in arabinose (312.22 ± 7.54 mg g -1 polysaccharide extract) and glucose (279.22 ± 5.59), and promising cytostatic effect.

A new HPLC-UV technique for the separation and analysis of 10 monosaccharides achieved within 13.5 min using 1-phenyl-3-methyl-5-pyrazolone (PMP) as the labelling molecule of the reductive monosaccharides has been established by combining common high performance liquid chromatography-UV and C18 column. The established technique was applied to the quantification of the monosaccharide components in extract of Silybum marianum. The results showed that the tested 10 monosaccharides as PMP derivatives were baseline separated under the HPLC conditions proposed. It was confirmed that Silybum marianum extract was composed of mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, xylose, galactose and arabinose with the molar ratio of 0.66:0.84:0.58:1.0:1.6:0.69:2.7:4.8. Quantitative recoveries of the compositional monosaccharides separated from the extract were in the range of 92.4%-104.0%, and the RSD values fell within 0.68%-3.81%. The results demonstrated that the proposed HPLC method was simple, rapid, convenient, and precise, and it was applicable to the analysis of the compositional monosaccharides of Silybum marianum extract.

Detailed structures of the active polysaccharides extracted from the leaf and stem cell walls and mucilage of Dendrobium huoshanense are determined by using various techniques, including chromatographic, spectroscopic, chemical, and enzymatic methods. The mucilage polysaccharide exhibits specific functions in activating murine splenocytes to produce several cytokines including IFN-gamma, IL-10, IL-6, and IL-1alpha, as well as hematopoietic growth factors GM-CSF and G-CSF. However, the deacetylated mucilage obtained from an alkaline treatment fails to induce cytokine production. The structure and bioactivity of mucilage components are validated by further fractionation. This is the first study that provides clear evidence for the structure and activity relationship of the polysaccharide in D. huoshanense.

The polysaccharide isolated from the gum exudate of palm Scheelea phalerata (SPN) was water-insoluble and composed of Fuc, Ara, Xyl, and uronic acid moieties in a 5:34:54:7 molar ratio: 12% of phenolics were also present. A soluble polysaccharide (SPNa) was obtained after alkaline treatment, which contained Fuc, Ara, Xyl and uronic acid in a 7:44:42:7 molar ratio, with only 2% phenolics. SPNa had an M(W) approximately 1.04 x 10(5) g mol(-1) and was almost monodisperse (M(W)/M(N) : 1.25 +/-0.22). It had a branched structure with side chains of 2-O-substituted Xylp (approximately 8%) and 3-O-substituted Araf (12%) units, and a large proportion of nonreducing end-units of Araf (15%), Fucp (10%), Xylp (4%), and Arap (6%). The (1 --> 4)-linked beta-Xylp main-chain units were 3-O- (9%), 2-O- (13%), and 2,3-di-O- (13%) substituted. Its (13)C NMR spectrum contained at least 9 C-1 signals, those at delta 108.6 and 107.7 arising from alpha-Araf units. Others were present at delta 175.4 from C-6 of alpha-GlcpA and delta 15.6 from C-6 of Fucp units. The main chain of SPNa was confirmed by analysis of a Smith-degraded polysaccharide (SPDS): methylation analysis provided a 2,3-Me(2)-Xyl (65%) derivative and its (13)C NMR spectrum showed five main signals typical of a (1 --> 4)-linked beta-Xylp units. Methylation analysis of a carboxy-reduced polysaccharide (SPN-CR) revealed a 2,3,4,6-Me(4)-Glc derivative (4%) arising from nonreducing end-units of GlcpA. Alpha-GlcpA-(1 --> 2)-alphabeta-Xy1p and alpha-GlcpA-(1 --> 2)-beta-Xylp-(1 --> 4)-alphabeta-Xylp were obtained via partial acid hydrolysis of SPN, showing the structure of side-chain substituents on O-2 of the main-chain units.

Aim: To study the structural characterization of an acidic polysaccharide, H3, isolated from the seeds of Cuscuta chinensis Lam., Methods: Both chemical (such as sugar component analysis, methylation analysis, reduction of uronic acid, partial acidic hydrolysis, etc.) and spectral analysis (1HNMR, 13CNMR, IR, etc.) were used to investigate the structural characterization of H3., Results: The molecular weight of H3 was estimated to be more than 1.0 x 10(6). The analytical results of sugar components indicated that H3 composed of Rha, Ara, Gal, and Gal A. Methylation analysis, partial acidic hydrolysis and 1H, 13CNMR further identified the linkages and sequence of the residues of H3., Conclusion: These results suggest that H3 is a highly branched heteropolysaccharide with structure elucidation for the first time.

Dried beans (kidney and great northern) and dried peas (chick, green, and yellow) were cooked according to package instructions. Total dietary fiber (TDF) was measured by the Mongeau (AOAC 992.16), Prosky (AOAC 985.29), and Lee (AOAC 991.43) methods (A, B, and C, respectively). Nonstarch polysaccharides (NSP) were measured by the Englyst gas-chromatographic method that included dimethyl sulfoxide treatment, and the lignin measured separately was added to NSP (method D). TDF was also measured by the Li method (E). TDF values ranged from 7 to 48 g/100 g dry weight. Methods B and C gave similar TDF values, which were higher than those from other methods. For kidney beans I, TDF values by methods B and C were up to 2.5 times higher because of the inclusion of starch. The fiber residues from methods A and C contained the same amounts of arabinose, xylose, mannose, galactose, and uronic acid, but glucose was 4 times higher in residue C than in residue A. When alpha-amylase from porcine pancreas was incorporated in methods B or C for 5 samples, the discrepancies among methods A, B, and C were reduced by 60-98%.

The structure of the polysaccharide from Cercidium praecox (R&P) Harms gum exudate has been studied by Smith degradation, by sugar and methylation analyses, and by 13C NMR spectroscopy. The results showed a (1-->4)-xylan core. Some xylose residues are substituted at O-2 by alpha-D-glucuronic acid and 4-O-methyl-alpha-D-glucuronic acid residues. beta-D-Glucuronic acid is present, probably as terminal residues. The arabinose is present as alpha-L-furanose and beta-L-pyranose.

Two water-soluble polysaccharide fractions, WSTP-IA and WSTP-IB were purified from the leaves of Tridax procumbens Linn. with graded ethanol precipitation followed by mild delignification and size-exclusion chromatography. WSTP-IA contained L-Araf and D-Galp in approximately 1:3 molar proportions, and WSTP-IB contained only D-Galp as the major sugar component. The results of methylation linkage analysis, and 1H and 13C NMR studies on the native and modified polysaccharides, indicated that WSTP-IA is an L-arabino-D-galactan with a beta-(1-->6)-D-galactan main chain in which at least one in every two D-Galp residues carries single residues of either L-Araf (alpha-/beta-) or beta-D-Galp end-group as substituents at O-3. WSTP-IB is a linear beta-(1-->6)-D-galactan. This is the first report of polysaccharides containing a beta-(1-->6)-D-galactan main chain isolated from plant sources.

Two acidic polysaccharides, called ginsenan S-IA and ginsenan S-IIA, were isolated from the root of Panax ginseng C. A. Meyer. They were homogeneous on electrophoresis and gel chromatography, and their molecular masses were estimated to be 5.6 x 10(4) and 1.0 x 10(5), respectively. Ginsenan S-IA is composed of L-arabinose: D-galactose: D-galacturonic acid in the molar ratio of 8:8:1, and ginsenan S-IIA is composed of L-arabinose: D-galactose: D-glucose: D-galacturonic acid in the molar ratio of 15:10:2:5, in addition to small amounts of O-acetyl groups. About a half (ginsenan S-IA) and about a quarter (ginsenan S-IIA) of the hexuronic acid residues exist as methyl esters. Reduction of carboxyl groups, methylation analysis, nuclear magnetic resonance and periodate oxidation studies indicated that their structural features include mainly alpha-1,5-linked L-arabino-beta-3,6-branched D-galactan type structural units. Both polysaccharides showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test and pronounced anti-complementary activity. These substances are the first examples having a relatively high content of both alpha-3,5-branched L-arabinose and beta-1,4-linked D-galactose units among the acidic arabinogalactans with activities on phagocytosis and anti-complement.

Antisera raised against the major hydroxyproline-rich glycoprotein (HRGP) in carrot (Daucus carota L.) taproot, extensin-1, and a minor HRGP, extensin-2, were characterized by western blot analysis, enzyme-linked immunosorbent assay, and periodate oxidation and found to be directed against carbohydrate epitopes shared by both glycoproteins. The anti-extensin-1 antibodies (gE1) target periodate-sensitive epitopes and may recognize the terminal alpha-1,3-arabinoside of extensin-1. The anti-extensin-2 antibodies (gE2) recognize periodate-insensitive epitopes, possibly binding the reducing, internal beta-1,2-arabinosides on the carbohydrate side chains. Despite the cross-reactivity of these antibodies, immunolocalization studies of carrot taproot and green bean (Phaseolus vulgaris L.) leaf tissues reveal a spatial segregation of gE1- and gE2-labeling patterns. The gE1 antibodies bind only to the cellulose-rich region of the cell wall (J.P. Staehelin and L.A. Stafstrom [1988] Planta 174: 321-332), whereas gE2 labeling is restricted to the expanded middle lamella at three cell junctions. Periodate oxidation of nonosmicated, thin-sectioned tissue abolishes gE1 labeling but leads to labeling of the entire cell wall by gE2, presumably as a result of unmasking cryptic epitopes on extensin-1 in the cellulose layer. Purified extensin-2 protein is more efficient than extensin-1 protein at agglutinating avirulent Pseudomonas strains lacking extracellular polysaccharide. Our results indicate that extensin-2 does not form a heterologous HRGP network with extensin-1 and that, in contrast to extensin-1, which appears to serve a structural role, extensin-2 could participate in passive defense responses against phytopathogenic bacteria.

Graded hydrolysis of purified bael gum afforded three neutral and two acidic oligosaccharides, together with monosaccharides. These sugars were identified through periodate oxidation, methylation, reduction with lithium aluminum hydride, co-chromatography, and preparation of crystalline derivatives. The neutral oligosaccharides were characterized as 3-0-beta-D-galactopyranosyl-L-arabinose, 5-0-beta-D-galactopyranosyl-L-arabinose, and 3-0-beta-D-galactopyranosyl-D-galactose, and the acidic oligosaccharides as 3-0-(beta-D-galactopyranosyluronic acid)-D-galactose and 3-0-(beta-D-galactopyranosyluronic acid)-3-0-beta-D-galactopyranosyl-D-galactose.

An anti-complementary polysaccharide, AR-arabinogalactan, was isolated from the roots of Angelica acutiloba Kitagawa (Japanese name = Yamato-Tohki), and purified by chromatography on DEAE-Sephadex A-50, Sephadex G-100, Sepharose CL-2B and concanavalin A-Sepharose. AR-arabinogalactan was composed of arabinose and galactose in a molar ratio of 1.2:1.0 and a small amount of galacturonic acid. The results of methylation and exo-alpha-L-arabinofuranosidase treatment showed that the polysaccharide was a branched arabinogalactan containing a backbone involving galactopyranosyl (1----6) linkages. Most of the arabinose was present as an alpha-L-furanosyl residue in the non-reducing terminals and side chains. The (1----3)-linked galactopyranosyl residue might be linked to the arabinosyl side chains. alpha-L-arabinofuranosidase digestion did not destroy the anti-complementary activity of the polysaccharide. After incubation of the serum with AR-arabinogalactan in the absence of Ca2+ ions, a cleavage of C3 in the serum was detected by immunoelectrophoresis as well as from the consumption of complement when rabbit erythrocytes were used in the assay system. A marked consumption of C4 was also observed to have occurred when serum was incubated with AR-arabinogalactan in the presence of Ca2+ ions. Collectively considered these results indicate that the mode of complement activation by AR-arabinogalactan is via both the alternative and the classical pathway.