Leaf and stem anatomy of Vochysiaceae in relation to subfamilial and suprafamilial systematics

Several leaf anatomical features are potentially systematically informative within both the family Vochysiaceae and the order Myrtales, notably tracheoidal idioblasts, mucilage cells and secretory canals. Tracheoids with spiral wall thickenings are present in the mesophyll of most species of Vochysia , and also occur in several other families of Myrtales. Mucilage cells are common in the leaf epidermis in some Vochysiaceae. Secretory ducts are present in the midrib in Salvertia and Vochysia , which are apparently closely related, although Salvertia also shares some leaf anatomical characters with Qualea and Callisthene . Anatomical data do not support the segregation of Ruizterania from Qualea ; leaves of R. albiflora leaves are very similar to those of Q. paraensis in venation pattern, and leaf and stem anatomy. Different venation patterns are characteristic of sections within the genus Qualea , but within the large genus Vochysia , leaf anatomy is variable even within a subsection. Amongst other Myrtales, leaf anatomy of Vochysiaceae most closely resembles that of Combretaceae and Onagraceae. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 138 , 339–364.     

Aluminium accumulation by some cerrado native species of central Brazil

Summary Among thirty species belonging to seventeen families common in the cerrado region of central Brazil, eight species belonging to three families were found to accumulate aluminium in their leaves in considerable amounts (4,310 to 14,120 mg/kg on dry weight basis) from a dark red latossol which is strongly-acid and low in available nutrient cations. The aluminium-accumulating species areMiconia ferruginata (DC.) Cogn.,Miconia pohliana Cogn. (Melastomataceae);Palicourea rigida H. B. K. (Rubiaceae);Qualea grandiflora Mart.,Qualea multiflora Mart.,Qualea parviflora Mart. (Vochysiaceae);Vochysia elliptica (Spr.) Mart., andVochysia thyrsoidea Pohl (Vochysiaceae). High levels of aluminium in the leaves of these plants were not associated with low foliar levels of calcium, magnesium, potassium, iron, manganese, zinc, or phosphorus as compared to the other species which do not accumulate aluminium. In spite of the low pH and the low base saturation of the soil the aluminium-accumulating species seem to have an efficient mechanism for absorbing all cations from the soil.     

Al-hyperaccumulator Vochysiaceae from the Brazilian Cerrado store aluminum in their chloroplasts without apparent damage

We investigated the pattern of aluminum (Al) accumulation in leaf tissues of native hyperaccumulator Vochysiaceae species Qualea grandiflora,Callisthene major, and Vochysia pyramidalis, from the Brazilian Cerrado. Non-accumulator Sclerolobium paniculatum was used as a control species. We expected a strong compartmentalization of Al in non-active leaf cell compartments such as cell walls and vacuoles in Al-accumulating species and the absence of Al in critical metabolic sites such as the chloroplasts. Plant leaves were harvested in the field and cut in small segments for histological analysis; hematoxylin dye was used for Al localization in tissues. Results of soil analysis of the three sites and the concentration of Al in leaves indicated that there is no direct relationship between Al availability in soils and Al hyperaccumulation among the Vochysiaceae species evaluated. The cross-sections of leaf tissues showed hematoxylin color in the palisade and spongy parenchyma cells (chloroplast) of Q. grandiflora and C. major. The vascular system of Q. grandiflora was not colored, but some cells from the xylem region of C. major were stained. In contrast, the adaxial and abaxial epidermal cells of V. pyramidalis were colored by hematoxylin, as were some cells from the vascular bundle, but color formation was not observed in the cells of palisade parenchyma. Al was not detected in leaves of S. paniculatum. We concluded that, although hyperaccumulation of Al is a common trait in the Vochysiaceae family, the processes of storage and detoxification in leaf tissues differ among the species. Two of the three hyperaccumulator species use chloroplasts as a sink for Al, with no apparent signs of toxicity. Therefore, the physiological role of Al in plant tissues remains to be elucidated.     

Comparison of carbohydrate substrate preferences in eight species of bifidobacteria

Eight species of bifidobacteria were tested for their abilities to grow on a range of monosaccharides (glucose, arabinose, xylose, galactose and mannose). In contrast to the other sugars, glucose and galactose were utilized by all species and, in general, specific growth rates were highest on these sugars. Different substrate preferences were observed between species when the bacteria were grown in the presence of all five monosaccharides. For example, glucose and xylose were coutilized by Bifidobacterium longum, whereas glucose repressed uptake of all other sugars in B. bifidum and B. catenulatum. Galactose was the preferred substrate with B. pseudolongum. In B. angulatum, glucose and galactose were utilized simultaneously. B. breve did not grow on arabinose when this sugar provided the sole source of energy. However, glucose and arabinose were preferentially taken up during growth on sugar mixtures.     

Protoplast isolation and culture from carob (Ceratonia siliqua) hypocotyls: ability of regenerated protoplasts to produce mannose-containing polysaccharides

The aim of this study was to isolate protoplasts from carob (Ceratonia siliqua L.) embryonic tissues with the ability to regenerate cell walls, divide and synthesize galactomannan, a valuable polysaccharide for industry. Protoplasts isolated from carob hypocotyl hooks regenerated cell walls within 24 h. The first divisions of the regenerated cells were observed after 2 days of culture. The highest percentage that successfully divided was achieved when the seedlings were grown under diffuse light, the hypocotyl hooks were plasmolysed for 1 h before incubation in the protoplast isolation solution and the protoplasts were cultured under diffuse light. After 9 days of culture, cell clusters, consisting of eight cells, had been produced, which underwent further mitotic divisions and which were expected to lead to callus formation. Polysaccharide and oligosaccharide synthesis during protoplast regeneration was studied by radiolabelling with exogenous d ‐[U‐¹⁴C]glucose, d ‐[U‐¹⁴C]mannose or d ‐[2‐³H]mannose, which gave rise to uniform, moderately specific and highly specific labelling, respectively. As revealed by the radioactivity distribution in cell wall monosaccharides, the regenerants deposited new wall polymers that differed markedly from those being synthesized by the hypocotyls from which the protoplasts had been isolated. The regenerants deposited large amounts of callose and smaller amounts of galactose‐, arabinose‐ and mannose‐containing polymers. The latter included glucuronomannan, as demonstrated by a new method involving partial acid hydrolysis followed by β‐glucuronidase (EC 3.2.1.31) digestion. The regenerating protoplasts also released soluble extracellular carbohydrates: polysaccharides which appeared to be mainly acidic arabinogalactans, and oligosaccharides which were mainly neutral and contained glucose, galactose and mannose. We conclude that regenerating carob protoplasts are a useful system for studying carbohydrate secretion, including mannose‐rich poly‐ and oligosaccharides.     

Composition of the walls of pollen grains of the seagrass Amphibolis antarctica

The composition of walls isolated from pollen grains of the seagrass Amphibolis antarctica was determined. Glucose, galactose, and rhamnose were the major neutral monosaccharides in the wall polysaccharides, and fucose, arabinose, xylose, and mannose were present in minor proportions. No apiose, a monosaccharide present in the wall polysaccharides of the vegetative parts of the seagrass Heterozostera tasmanica, was found. Large amounts of uronic acid (mainly as galacturonic acid) were found in the walls. The monosaccharides were probably present in cellulose and pectic polysaccharides, the latter comprising neutral pectic galactans, and rhamnogalacturonans containing high proportions of rhamnose. The walls contained a small amount of protein; glycine and lysine were the amino acids present in the highest proportions. Histochemical examination of isolated walls confirmed the presence of polyanionic components (pectic polysaccharides), -glucans (cellulose), and protein. The composition of the walls is discussed in relation to analyses of the walls of pollen grains and vegetative organs of other plants.     

STUDIES ON POLYSACCHARIDES FROM THREE EDIBLE SPECIES OF NOSTOC (CYANOBACTERIA) WITH DIFFERENT COLONY MORPHOLOGIES: COMPARISON OF MONOSACCHARIDE COMPOSITIONS AND VISCOSITIES OF POLYSACCHARIDES FROM FIELD COLONIES AND SUSPENSION CULTURES

Hot water-soluble polysaccharides were extracted from field colonies and suspension cultures of Nostoc commune Vaucher, Nostoc flagelliforme Berkeley et Curtis, and Nostoc sphaeroides Kützing. Excreted extracellular polymeric substances (EPS) were isolated from the media in which the suspension cultures were grown. The main monosaccharides of the field colony polysaccharides from the three species were glucose, xylose, and galactose, with an approximate ratio of 2:1:1. Mannose was also present, but the levels varied among the species, and arabinose appeared only in N. flagelliforme. The compositions of the cellular polysaccharides and EPS from suspension cultures were more complicated than those of the field samples and varied among the different species. The polysaccharides from the cultures of N. flagelliforme had a relatively simple composition consisting of mannose, galactose, glucose, and glucuronic acid, but no xylose, as was found in the field colony polysaccharides. The polysaccharides from cultures of N. sphaeroides contained glucose (the major component), rhamnose, fucose, xylose, mannose, and galactose. These same sugars were present in the polysaccharides from cultures of N. commune, with xylose as the major component. Combined nitrogen in the media had no qualitative influence on the compositions of the cellular polysaccharides but affected those of the EPS of N. commune and N. flagelliforme. The EPS of N. sphaeroides had a very low total carbohydrate content and thus was not considered to be polysaccharide in nature. The field colony polysaccharides could be separated by anion exchange chromatography into neutral and acidic fractions having similar sugar compositions. Preliminary linkage analysis showed that 1) xylose, glucose, and galactose were 1→4 linked, 2) mannose, galactose, and xylose occurred as terminal residues, and 3) branch points occurred in glucose as 1→3,4 and 1→3,6 linkages and in xylose as a 1→3,4 linkage. The polymer preparations from field colonies had higher kinematic viscosities than those from correspondingsuspension cultures. The high viscosities of the polymers suggested that they might be suitable for industrial uses.     

宁夏不同地区灵武长枣果实多糖的单糖成分分析

以宁夏4个不同地区(灵武、中宁、青铜峡、银川)成熟期的灵武长枣果实为研究对象,经水提醇沉法提取,采用DEAE-cellulose52和HW-55S分离纯化,并利用GC-MS法进行多糖的单糖组成分析。结果表明:多糖提取率最高的是灵武地区,达到1.795%;分离纯化后,4个地区的长枣多糖各得到1个中性(Ju-0)和3个酸性组分(Ju-1、Ju-2、Ju-3),其中Ju-2含量最高;GC-MS分析可知灵武长枣多糖含有阿拉伯糖、鼠李糖、核糖、岩藻糖、木糖、甘露糖、半乳糖、葡萄糖、葡萄糖醛酸、半乳糖醛酸10种单糖,不含果糖,以阿拉伯糖、核糖、半乳糖和2种糖醛酸为主,木糖含量最低。各地区多糖的单糖组成、含量各不相同,从各组分来看,四个地区多糖的Ju-0和Ju-1组分组成均以阿拉伯糖、核糖、半乳糖为主,四个地区多糖的组成差异主要在于Ju-2和Ju-3组分。从各地区单糖总量来看,灵武地区是阿拉伯糖含量最高,中宁、青铜峡、银川地区以葡萄糖醛酸含量为最高。     

Distribution of seed fatty acids and the taxonomy of Vochysiaceae

The distribution of seed fatty acids of 16 species of Vochysiaceae native to Brazil, corresponding to the genera Callisthene, Qualea, Salvertia and Vochysia, and amounting to 57 samples, were studied. The methyl esters of the fatty acids were analyzed by GC–EIMS. For most species, fatty acid patterns are seemingly useful for species characterization. Intraspecific variability of samples of Salvertia grandiflora seems to have geographic significance. With one exception, palmitic and oleic acids predominate in the fatty acids distribution of Qualea and Callisthene. Q. grandiflora possesses exceptional amounts of lauric acid. Relatively high amounts of either C_20–C₂₂ (saturated or monounsaturated) or stearic acids characterize Salvertia and Vochysia. UPGMA analysis of fatty acids distribution based on Euclidean distances resulted in a cluster combining Callisthene and all samples of Qualea, except Q. grandiflora. Samples of Vochysia are combined into several clusters. The dendrogram is suggestive of taxonomic relationships, allowing the distinction of taxa down to the sub-sectional level. V. pyramidalis, from section Ciliantha, subsection Ferrugineae, has closer chemical affinities with species of section Vochysiella, subsection Decorticantes. Comparing with monomers of polysaccharide seed cell walls of Vochysiaceae, fatty acid patterns revealed lower intraspecific variability and higher taxonomic resolution.     

Sugars in hydrolysates of fungal melanins and soil humic acids

Humic acids from four Brazilian topsoils of different origin and four fungal melanins, synthesized under two cultural conditions were subjected to a two step hydrolysis procedure and the released monosaccharides qualitatively and quantitatively determined by gas-liquid chromatography. The neutral sugars, glucose, galactose, mannose, arabinose, xylose, fucose, rhamnose and the alcohol sugar inositol, were detected in most of the soil humic acid samples. The fungal melanins showed the presence of glucose, galactose, mannose and arabinose. Ribose was present in two out of the eight samples tested. Some quantitative differences in the two types of humic polymers were noted and expected considering their origins. However, similarities were more apparent than differences and give further indication that melanic fungi may play a significant role in the formation of soil humic acids.     

Cell-Wall Carbohydrates of the Endosperm of the Seed of Gleditsia triacanthos

The endosperm of the seed of Gleditsia triacanthos L. contains 18.55% of its dry weight as nonreserve, cell-wall carbohydrates. Of this carbohydrate material, comprising mainly mannose, galactose, and glucose, 76.1% was of low-molecular weight or highly hydrophilic. Mannose, galactose, and glucose were also the major sugar components of the polysaccharides extracted with alkali (23.1% of the cell-wall), while the same sugars, with minor amounts of arabinose, form the residues. Methylation analysis of the polysaccharides and the borate-sodium hydroxide residue indicate that the cell walls are built up on a network of galactomannans, with high Man/Gal ratios, reinforced with minor amounts of cellulose.     

Purification and Partial Characterization of Polysaccharides From Coconut Milk

Ethanol-precipitated polysaccharides of the liquid endospermof coconut, Cocos nucifera L., were composed predominantly ofgalactose and arabinose with minor amounts of mannose and glucose.Gel filtration chromatography on Bio-Gel A-0.5 m revealed asingle major peak (Peak A) at the void volume and a minor peak(Peak B) partially included in the column volume. Peak A containedsome uronosyl residues, but was not susceptible to cleavageby endopolygalacturonase, indicating that it does not containsignificant amounts of polygalacturonic acid. Neutral glycosylresidue composition analysis of Peak A showed that it consistedof 72% galactose and 24% arabinose with minor amounts of glucoseand rhamnose. Coconut milk, Cocos nuciferaL, polysaccharides, glycosyl composition     

A simple procedure for the synthesis of alpha-32P-nucleoside triphosphates.

Chemical analysis of grapefruit (Citrus paradisi) pectic polysaccharides demonstrated that galacturonic acid constitutes 78% by weight of the total carbohydrates found. The remaining 22% was accounted for by a number of sugars which include galactose, glucose, arabinose, xylose, and mannose and, by weight, galactose accounted for almost 50% of the total neutral sugar components found in these pectic polysaccharides. Treatment of pectic polysaccharides with galactose oxidase followed by reduction of oxidized galactose residues with tritiated potassium borohydride resulted in the labeling of pectic polysaccharides. Analysis of the labeled polysaccharides demonstrated that of the total radioactivity incorporated more than 90% was recovered in the galactose residues. These results clearly demonstrate the successful utilization of the galactose oxidase/tritiated potassium borohydride method in labeling plant pectic polysaccharide.     

Water-soluble polysaccharides from Ginkgo biloba leaves.

The water-soluble polysaccharides from dried Ginkgo biloba leaves were isolated after exhaustive extraction with organic solvents. The polysaccharide mixture could be separated into a neutral (GF1) and two acidic (GF2 and GF3) polysaccharide fractions by ion exchange chromatography. According to the Mr distribution GF1 and GF3 seemed to be homogenous, whereas GF2 could be further fractionated into two subfractions (GF2a and GF2b) by gel permeation chromatography. GF1 (Mr 23,000) showed the structural features of a branched arabinan. The main chain was composed of 1,5-linked arabinose residues and three in 12 arabinose molecules were branched via C-2 or C-3. GF2a (Mr 500,000) consisted mainly of 1,2,4-branched mannose (29%), 1,4-linked glucuronic (32%) and galacturonic (8%) acid as well as terminal rhamnose (25%). After removal of ca 70% of the terminal rhamnose the remaining polysaccharide showed a decrease in 1,2,4-branched mannose and an increase in 1,2-linked mannose indicating that at least half of the rhamnose residues were linked to mannose via C-4. GF3 (Mr 40,000) consisted of 1,4-linked galacturonic (30%) and glucuronic (16) acid, 1,3,6-branched galactose (15%), 1,2-linked (5%) and 1,2,4-branched (3.5%) rhamnose as well as 1,5-linked arabinose (11%). Rhamnose (5%) and arabinose (10%) were present as terminal groups. Mild acid hydrolysis selectively cleaved arabinose and the remaining polysaccharide showed an increased amount of 1,6-linked and terminal galactose and a decreased quantity of 1,3,6-branched galactose. These results indicated that the terminal as well as the 1,5-linked arabinose were mainly connected to galactose via C-3. The GF3 polysaccharide appeared to be a rhamnogalacturonan with arabinogalactan side chains.     

Compositional features of carbohydrate compound from rhizoma ligustici wallichii and ethanol extract of danshen and its bioactivity

Water extraction was applied to prepare carbohydrate compound of rhizoma ligustici wallichii. Four main fractions, fraction-I, fraction-II, fraction-III, and fraction-IV, were obtained by membranes of 1.0 × 10⁻⁴ mm pore size and normal molecular-weight cut-off of 50 kDa. The resulting four preparations were further analysed by capillary gas chromatography method. Thin layer chromatography (TLC) analysis showed that carbohydrate compound of rhizoma ligustici wallichii was composed of five types of monosaccharides, namely glucose, rhamnose, mannose, galactose and arabinose. Gas chromatography (GC) analysis showed that fraction I of rhizoma ligustici wallichii was composed of four types of monosaccharides, namely glucose, mannose, galactose and arabinose at a molar ratio of 521:1:4.6:3.3. Furthermore, the protective effect of the Rhizoma ligustici wallichii polysaccharides and ethanol extract of danshen against ischemia-reperfusion (IR) induced renal injury were evaluated. The findings imply that carbohydrate compound of the Rhizoma ligustici wallichii and ethanol extract of danshen play a causal role in IR-induced renal injury probably by the radical scavenging and antioxidant activities. Moreover, ethanol extract of danshen displayed stronger renoprotective effect than that of carbohydrate compound of the Rhizoma ligustici wallichii.     

Polysaccharide compositions of primary cell walls of the palms Phoenix canariensis and Rhopalostylis sapida

The polysaccharide compositions of unlignified primary cell walls from two species of palms were examined. Cell-wall preparations were isolated from the stem apex, including the pre-emergent leaflets and rachides, of Phoenix canariensis (Canary Island date palm), and from leaflets and rachides dissected from pre-emergent leaves in the stem apex of Rhopalostylis sapida (Nikau palm). The non-cellulosic polysaccharides in the cell-wall preparations from both species had similar monosaccharide compositions, with arabinose and galactose being the predominant neutral monosaccharides, together with large amounts of galacturonic acid. These monosaccharide compositions indicated the presence of large proportions of pectic polysaccharides, including homogalacturonans. This was confirmed by linkage analyses of the cell-wall preparations which showed the presence of large proportions of pectic arabinans, together with pectic galactans and/or Type I arabinogalactans. Evidence for rhamnogalacturonan I and small amounts of rhamnogalacturonan II was also obtained. In addition to pectic polysaccharides, the cell-wall preparations contained smaller amounts of xyloglucans and even smaller amounts of heteroxylans, probably glucuronoarabinoxylans, and glucomannans and/or galactoglucomannans; (1→3,1→4)-β-D-glucans were not present. Although palms (Arecaceae) are commelinoid monocotyledons, the polysaccharide compositions of their primary cell walls resemble those of non-commelinoid monocotyledons and dicotyledons. These compositions contrast with those of primary cell walls of other commelinoid families which have glucuronoarabinoxylans rather than pectic polysaccharides as the major non-cellulosic polysaccharides. The results are discussed in relation to the possible evolution of the composition of primary cell walls of monocotyledons.     

Water-soluble polysaccharides of antarctic and cultured Phormidium species of the cyanophyceae

Hot water extraction of a Phormidium species from Antarctica and of a sample of Phormïdium foveolarum which had been cultured axenically led to the isolation of a water-soluble polysaccharide from both materials. Acidic hydrolysis of each gave a similar pattern of monosaccharides comprising arabinose, xylose, rhamnose, fucose, galactose, mannose and glucose, and both contained uronic acid. All attempts by a variety of methods to fractionate the Antarctic polysaccharide into more than a single entity were unsuccessful. Periodate oxidation, partial hydrolysis and methylation studies on this polysaccharide supported a highly branched molecule with 1,3-linked glucose and 1,4-linked galactose as dominant features.     

Chemical characterisation of the released polysaccharide from the cyanobacterium Aphanothece halophytica GR02

The released polysaccharide from the halophilic cyanobacterium Aphanothece halophytica GR02 was separated into two main fractions byanion-exchange chromatography. The major fraction consisted of glucose,fucose, mannose, arabinose and glucuronic acid. Judging from thechromatography on Sepharose 2B, the major fraction was not furtherfractionated, and its apparent molecular weight was above 2.0 × 10⁶ Da.The minor fraction consisted of rhamnose, mannose, fucose,glucose, galactose and glucuronic acid, with traces of arabinose.Methylation and GC-MS spectrometry analyses of the major fractionrevealed the presence of 1-linked glucose, 1,3-linked glucose, 1,3-linkedfucose, 1,4-linked fucose, 1,3-linked arabinose, 1,2,4-linked mannose,1,3,6-linked mannose, 1-linked glucuronic acid and 1,3-linked glucuronicacid residues. The major fraction was thought to originate from capsularpolysaccharide. The released polysaccharides, obtained from cultures atdifferent age of culture, showed no striking variations in themonosaccharide composition and the relative proportions of themonosaccharides. However, the proportions of galactose and rhamnose inthe released polysaccharides, obtained from cultures under different salinity,were significantly different. The released polysaccharide also exhibitedgelling properties and strong affinity for metal ions.     

Analysis of chemical components of shiitake polysaccharides and its anti-fatigue effect under vibration

The shiitake polysaccharides were obtained from shiitake mushroom. Four fractions were isolated from the polysaccharides using a Sephadex G-100 gel column. Chemical components of the two main fractions were determined by thin layer chromatography (TLC), and high performance liquid chromatography (HPLC). F1 was composed of rhamnose, glucose, and mannose. F3 was composed of xylose, mannose, arabinose and galactose. The obtained results still showed that administration of shiitake polysaccharides could improve muscle's comfortability of animals under a long period of vibration. The above findings might be applicable to studies of vibration ergonomics.