Assessment of Durum Wheat (Triticum durum Desf.) Genotypes Diversity for the Integrated Production of Bioethanol and Grains

Wheat straw is an abundant source of lignocellulosic biomass that is generally not utilized for biofuel production, nor for other uses. Recent EU renewable energy directive fosters bioethanol production through lignocellulosic sugars fermentation, but the cost of this process is an issue that often depends on biomass characteristics. Lignin is a class of three-dimensional polymers providing structural integrity of plant tissues. Its complex structure, together with hemicelluloses and uronic acids content, could affect the ability of hydrolyzing biomass to fermentable sugars. To get insights into this variation, a set of 10 durum wheat genotypes was analyzed to determine variation of straw digestibility to fermentable sugars. The results showed that the lignin content was the major factor determining the recalcitrance to enzymatic process. The analysis of Spearman’s correlation indicated that the sugar released after enzymatic hydrolysis had a negative connection with the lignin content, while it was positively correlated with the culm length. The possible role of other cell wall components, such as arabinose and uronic acids, was also discussed. This work aimed at analyzing the diversity of lignocellulosic digestibility to fermentable sugars of wheat straw in a small germplasm collection. Some of the selected genotypes were characterized by high sugars digestibility and high grain yield, characteristics that could make biorefining of wheat straw profitable.

Degraded Arabinogalactans and Their Binding Properties to Cancer-Associated Human Galectins

Galectins represent β-galactoside-binding proteins with numerous functions. Due to their role in tumor progression, human galectins-1, -3 and -7 (Gal-1, -3 and -7) are potential targets for cancer therapy. As plant derived glycans might act as galectin inhibitors, we prepared galactans by partial degradation of plant arabinogalactan-proteins. Besides commercially purchased galectins, we produced Gal-1 and -7 in a cell free system and tested binding capacities of the galectins to the galactans by biolayer-interferometry. Results for commercial and cell-free expressed galectins were comparable confirming functionality of the cell-free produced galectins. Our results revealed that galactans from Echinacea purpurea bind to Gal-1 and -7 with KD values of 1–2 µM and to Gal-3 slightly stronger with KD values between 0.36 and 0.70 µM depending on the sensor type. Galactans from the seagrass Zostera marina with higher branching of the galactan and higher content of uronic acids showed stronger binding to Gal-3 (0.08–0.28 µM) compared to galactan from Echinacea. The results contribute to knowledge on interactions between plant polysaccharides and galectins. Arabinogalactan-proteins have been identified as a new source for production of galactans with possible capability to act as galectin inhibitors.

Chemical synthesis of C6-tetrazole D-mannose building blocks and access to a bioisostere of mannuronic acid 1-phosphate

Alginate, an anionic polysaccharide, is an important industrial biomaterial naturally harvested from seaweed. Many of its important physicochemical properties derive from the presence of charged carboxylate groups, presented as uronic acids, within the polysaccharide backbone. An ability to design and synthesise isosteres of these carboxylates would ultimately enable access to new alginate systems possessing different physicochemical properties. We present herein an approach to the chemical synthesis of alginate building blocks, modified at the carboxylate C6 position with bioisosteric tetrazole. The development of this synthesis enables utilisation of C6-tetrazole donors to deliver anomeric phosphate and 3-aminopropyl free sugars containing this motif. Access to these building blocks will further enable glycosylation methodologies to be explored that incorporate tetrazole as a bioisostere within uronic acid-containing carbohydrates.

A TEMPO-catalyzed oxidation-reduction method to probe surface and anhydrous crystalline-core domains of cellulose microfibril bundles

A modified TEMPO-catalyzed oxidation of the solvent-exposed glucosyl units of cellulose to uronic acids, followed by carboxyl reduction with NaBD 4 to 6-deutero- and 6,6-dideuteroglucosyl units, provided a robust method for determining relative proportions of disordered amorphous, ordered surface chains, and anhydrous core-crystalline residues of cellulose microfibrils inaccessible to TEMPO. Both glucosyl residues of cellobiose units, digested from amorphous chains of cellulose with a combination of cellulase and cellobiohydrolase, were deuterated, whereas those from anhydrous chains were undeuterated. By contrast, solvent-exposed and anhydrous residues alternate in surface chains, so only one of the two residues of cellobiosyl units was labeled. Although current estimates indicate that each cellulose microfibril comprises only 18 to 24 (1 , 4)- b eta-D-glucan chains, we show here that microfibrils of walls of Arabidopsis leaves and maize coleoptiles, and those of secondary wall cellulose of cotton fibers and poplar wood, bundle into much larger macrofibrils, with 67 to 86% of the glucan chains in the anhydrous domain. These results indicate extensive bundling of microfibrils into macrofibrils occurs during both primary and secondary wall formation. We discuss how, beyond lignin, the degree of bundling into macrofibrils contributes an additional recalcitrance factor to lignocellulosic biomass for enzymatic or chemical catalytic conversion to biofuel substrates.

Genes for degradation and utilization of uronic acid-containing polysaccharides of a marine bacterium Catenovulum sp. CCB-QB4

Background Oligosaccharides from polysaccharides containing uronic acids are known to have many useful bioactivities. Thus, polysaccharide lyases (PLs) and glycoside hydrolases (GHs) involved in producing the oligosaccharides have attracted interest in both medical and industrial settings. The numerous polysaccharide lyases and glycoside hydrolases involved in producing the oligosaccharides were isolated from soil and marine microorganisms. Our previous report demonstrated that an agar-degrading bacterium, Catenovulum sp. CCB-QB4, isolated from a coastal area of Penang, Malaysia, possessed 183 glycoside hydrolases and 43 polysaccharide lyases in the genome. We expected that the strain might degrade and use uronic acid-containing polysaccharides as a carbon source, indicating that the strain has a potential for a source of novel genes for degrading the polysaccharides. Methods To confirm the expectation, the QB4 cells were cultured in artificial seawater media with uronic acid-containing polysaccharides, namely alginate, pectin (and saturated galacturonate), ulvan, and gellan gum, and the growth was observed. The genes involved in degradation and utilization of uronic acid-containing polysaccharides were explored in the QB4 genome using CAZy analysis and BlastP analysis. Results The QB4 cells were capable of using these polysaccharides as a carbon source, and especially, the cells exhibited a robust growth in the presence of alginate. 28 PLs and 22 GHs related to the degradation of these polysaccharides were found in the QB4 genome based on the CAZy database. Eleven polysaccharide lyases and 16 glycoside hydrolases contained lipobox motif, indicating that these enzymes play an important role in degrading the polysaccharides. Fourteen of 28 polysaccharide lyases were classified into ulvan lyase, and the QB4 genome possessed the most abundant ulvan lyase genes in the CAZy database. Besides, genes involved in uronic acid metabolisms were also present in the genome. These results were consistent with the cell growth. In the pectin metabolic pathway, the strain had genes for three different pathways. However, the growth experiment using saturated galacturonate exhibited that the strain can only use the pathway related to unsaturated galacturonate.

A Rare Medicinal Herb Remusatia Vivipara

In this current era, the demand for herbal medicines and products is increasing globally, and herbal medicines are being used traditionally as well as for the modern systems for treatment of various diseases and ailments. There are so many plants that are under research for their potential therapeutic and pharmaceutical applications, and Remusatia Vivipara is one of that rare plants belonging to the family Araceae. There are 105 Genera; more than 3300 species persist locally in tropical and sub-tropical areas and world widely. Remusatia Vivipara is commonly known as “Hitchhiker Elephant ear”. Tribal people also named it as Lalkand. The root juice of Remusatia Vivipara used on the wound to dispel any germ and worms. Remusatia Vivipara has many folkloric applications like for Inflammation and arthritis treatment, analgesic, for disinfecting the Genitourinary tract, and treatment of reddish boils. Upon hydrolysis arabinose, galactose, glucose, mannose, xylose, and various uronic acids are the most commonly observed components. This review is an attempt to compile all the aspects and details of plant Remusatia vivipara.

Synthesis of 4-thiol-furanosidic uronate via hydrothiolation reaction

Uronic acids are not only important building blocks of bioactive molecules but also are widely used in the food and pharmaceutical industries. Its derivative, 4-thiol-furanosidic uronate was successfully synthesized and firstly reported here.

COMPARATIVE STUDY OF THE POLYSACCHARIDE COMPOSITION OF THE FRUITS LYCIUM BARBARUM L. AND LYCIUM LUTHENICUM MURR

The polysaccharide complex (PSCs) of the Lycium barbarum fruits (commercially available and introduced in the research Institute of Biotechnology of Gorsky GAU, RSO-Alania) and wild Lycium ruthenicum (Absheron District, Tugchay River valley) was studied for the first time. The PSC yield from Lycium barbarum L. fruits was 1. and 1.7 % versus 3.1% from Lycium ruthenicum . In the majority of cases, uronic acids are present in the fraction of water-soluble polysaccharides (WSPS-2) and pectin substances (PS) of Lycium ruthenicum in the amount of 60.0% and 58.0%, respectively. Arabinose is present in the largest amount in all PSK (more than 43%). The second largest monomer is galactose, which is also identified in all polysaccharides. The molecular weight of the 'acidic' and 'neutral' polysaccharides (WSPS-1 and WSPS-2) of the Lycium fruits under consideration differs to a significant extent.

A Comprehensive and Comparative Analysis of the Fucoidan Compositional Data Across the Phaeophyceae

In the current review, compositional data on fucoidans extracted from more than hundred different species were surveyed through the available literature. The analysis of crude extracts, purified extracts or carefully isolated fractions is included in tabular form, discriminating the seaweed source by its taxonomical order (and sometimes the family). This survey was able to encounter some similarities between the different species, as well as some differences. Fractions which were obtained through anion-exchange chromatography or cationic detergent precipitation showed the best separation patterns: the fractions with low charge correspond mostly to highly heterogeneous fucoidans, containing (besides fucose) other monosaccharides like xylose, galactose, mannose, rhamnose, and glucuronic acid, and contain low-sulfate/high uronic acid proportions, whereas those with higher total charge usually contain mainly fucose, accompanied with variable proportions of galactose, are highly sulfated and show almost no uronic acids. The latter fractions are usually the most biologically active. Fractions containing intermediate proportions of both polysaccharides appear at middle ionic strengths. This pattern is common for all the orders of brown seaweeds, and most differences appear from the seaweed source (habitat, season), and from the diverse extraction, purification, and analytitcal methods. The Dictyotales appear to be the most atypical order, as usually large proportions of mannose and uronic acids appear, and thus they obscure the differences between the fractions with different charge. Within the family Alariaceae (order Laminariales), the presence of sulfated galactofucans with high galactose content (almost equal to that of fucose) is especially noteworthy.