HPLC analysis of manno-oligosaccharides derived from Saccharomyces cerevisiae mannan using an amino column or a graphitized carbon column

Mannans and mannan oligosaccharides (MOS) from Saccharomyces cerevisiae - A sustainable source of functional ingredients

Sustainable industry practices and circular economy concepts encourage the transformation of production waste into by-products. Saccharomyces cerevisiae is widely used in fermentation industry worldwide, generating large amounts of spent yeast which is mainly directed to animal feed or discarded as waste. Instead of becoming and environmental problem, spent yeast can be directed to the extraction of valuable compounds such as mannans and mannan oligosaccharides (MOS). This review presents a compilation of the studies up to date regarding the different chemical, enzymatic, mechanical or physical processes addressed for mannans extraction and MOS production. Additionally, the existing studies on the chemical modification of mannans aimed to improve specific characteristics are also discussed. Finally, the more relevant bioactivities and potential applications of mannans, MOS and mannose are presented, together with products on the market containing these compounds.

Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: an update covering the period 2001-2002

This review is the second update of the original review on the application of MALDI mass spectrometry to the analysis of carbohydrates and glycoconjugates that was published in 1999. It covers fundamental aspects of the technique as applied to carbohydrates, fragmentation of carbohydrates, studies of specific carbohydrate types such as those from plant cell walls and those attached to proteins and lipids, studies of glycosyl-transferases and glycosidases, and studies where MALDI has been used to monitor products of chemical synthesis. Use of the technique shows a steady annual increase at the expense of older techniques such as FAB. There is an increasing emphasis on its use for examination of biological systems rather than on studies of fundamental aspects and method development and this is reflected by much of the work on applications appearing in tabular form.

Structural basis for recognition of high mannose type glycoproteins by mammalian transport lectin VIP36

VIP36 functions as a transport lectin for trafficking certain high mannose type glycoproteins in the secretory pathway. Here we report the crystal structure of VIP36 exoplasmic/luminal domain comprising a carbohydrate recognition domain and a stalk domain. The structures of VIP36 in complex with Ca(2+) and mannosyl ligands are also described. The carbohydrate recognition domain is composed of a 17-stranded antiparallel beta-sandwich and binds one Ca(2+) adjoining the carbohydrate-binding site. The structure reveals that a coordinated Ca(2+) ion orients the side chains of Asp(131), Asn(166), and His(190) for carbohydrate binding. This result explains the Ca(2+)-dependent carbohydrate binding of this protein. The Man-alpha-1,2-Man-alpha-1,2-Man, which corresponds to the D1 arm of high mannose type glycan, is recognized by eight residues through extensive hydrogen bonds. The complex structures reveal the structural basis for high mannose type glycoprotein recognition by VIP36 in a Ca(2+)-dependent and D1 arm-specific manner.

Separation of polar compounds using carbon columns

The objective of this review with 122 references is to provide structure and retention mechanisms of porous graphitic carbon by chromatographic analysis and computational chemical analysis of retention mechanisms. Synthesis methods of porous graphitic carbon are described. Applications for use as matrix for dynamic coating on porous graphitic carbon and direct separation of polar compounds on porous graphitic carbon demonstrated that the physical and chemical stability of graphitic carbons performed in both chromatography and extraction, especially for polar compounds, those are difficult on both silica-based and organic polymer-based packing materials. The disadvantage is difficult desorption of non-polar compounds adsorbed on the surface. The development of 3.5-microm particles improves the separation power of graphitic carbon columns with the high theoretical plate number.